Subscriber access provided by UB + Fachbibliothek Chemie | (FU-Bibliothekssystem)
Article
Proteins and Amino Acids in Fine Particulate Matter in Rural Guangzhou, Southern China: Seasonal Cycles, Sources and Atmospheric Processes Tianli Song, Shan Wang, Yingyi Zhang, Junwei Song, Fobang Liu, Pingqing Fu, Manabu Shiraiwa, Zhiyong Xie, Dingli Yue, Liuju Zhong, Junyu Zheng, and Senchao Lai Environ. Sci. Technol., Just Accepted Manuscript • Publication Date (Web): 15 May 2017 Downloaded from http://pubs.acs.org on May 15, 2017
Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.
Environmental Science & Technology is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.
Page 1 of 33
Environmental Science & Technology
1
Proteins and Amino Acids in Fine Particulate Matter in Rural
2
Guangzhou, Southern China: Seasonal Cycles, Sources and
3
Atmospheric Processes
4
Tianli Song†,○, Shan Wang†,○, Yingyi Zhang*,†, Junwei Song†, Fobang Liu‡, Pingqing Fu§,
5
Manabu Shiraiwaǁ, Zhiyong Xie , Dingli Yue∇, Liuju Zhong∇, Junyu Zheng†, Senchao
6
Lai *,†
⊥
7 8
†
9
Control, School of Environment and Energy, South China University of Technology,
Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution
10
Guangzhou, China
11
‡
12
Germany
13
§
14
Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing,
15
China
16
ǁ
17
Multiphase Chemistry Department, Max Planck Institute for Chemistry, Mainz,
State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric
Department of Chemistry, University of California, Irvine, CA, USA
⊥
Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, Institute of
18
Coastal Research, Geesthacht, Germany
19
∇Guangdong
20
Laboratory of Regional Air Quality Monitoring, Guangzhou, China
Environmental Monitoring Center, State Environmental Protection Key
21 1 ACS Paragon Plus Environment
Environmental Science & Technology
22
○
23
*Corresponding Author: phone: +86-135-7097-4216; e-mail:
[email protected].
24
phone: +86-156-9242-3889; e-mail:
[email protected].
These authors contributed equally.
25
2 ACS Paragon Plus Environment
Page 2 of 33
Page 3 of 33
26 27
Environmental Science & Technology
TOC/ Abstract Art
3 ACS Paragon Plus Environment
Environmental Science & Technology
28
ABSTRACT: Water-soluble proteinaceous matter including proteins and free amino
29
acids (FAAs) as well as some other chemical components was analyzed in fine particulate
30
matter (PM2.5) samples collected over a period of one year in rural Guangzhou. Annual
31
averaged protein and total FAAs concentrations were 0.79 ± 0.47 µg m-3 and 0.13 ± 0.05
32
µg m-3, accounting for 1.9 ± 0.7% and 0.3 ± 0.1% of PM2.5, respectively. Among FAAs,
33
glycine was the most abundant species (19.9%), followed by valine (18.5%), methionine
34
(16.1%) and phenylalanine (13.5%). Both proteins and FAAs exhibited distinct seasonal
35
variations with higher concentrations in autumn and winter than those in spring and
36
summer. Correlation analysis suggests that aerosol proteinaceous matter was mainly
37
contributed by intensive agricultural activities, biomass burning and fugitive dust/soil
38
resuspension. Significant correlations between proteins/FAAs and atmospheric oxidant
39
(O3) indicate that proteins/FAAs may be involved in O3 related atmospheric processes.
40
Our observation confirms that FAAs could be degraded from proteins under the influence
41
of O3 and the stoichiometric coefficients of the reactions were estimated for FAAs and
42
glycine. This finding provides a possible pathway for the production of aerosol FAAs in
43
the atmosphere, which will improve the current understanding on atmospheric processes
44
of proteinaceous matter.
4 ACS Paragon Plus Environment
Page 4 of 33
Page 5 of 33
45
Environmental Science & Technology
1. INTRODUCTION
46
Proteinaceous matter is an important fraction of atmospheric aerosols, accounting for
47
up to ~5% of urban particulate matter.1 There are two forms of proteinaceous matter in
48
aerosols, namely free and combined amino acids (proteins and peptides). Due to their
49
influences on hygroscopic growth, microstructural rearrangement and crystal/droplet
50
properties, aerosol proteinaceous matter may act as ice nuclei (IN) and cloud
51
condensation nuclei (CCN) to affect atmospheric radiation balance and climate.2,
52
Proteinaceous matter can cause adverse health effects because of their allergenicity4, 5 and
53
deleterious effects on human health especially with their post-translational modified
54
forms.6-9 Besides, proteins and amino acids (AAs) are considered to be the major forms
55
of organic nitrogen compounds in atmospheric aerosols, and contribute to the
56
atmosphere-biosphere nutrient cycling and global nitrogen cycle.10, 11
3
57
Water-soluble proteins in aerosols have been analyzed to evaluate the levels of
58
biological particles in Mexico,12, 13 China,14 Ecuador,15 and the US.4, 16-20 As an important
59
class of organic nitrogen and organic carbon compounds, free amino acids (FAAs) in
60
aerosols have been investigated in different areas, including urban/suburban,21-25 rural,26,
61
27
62
proteins and FAAs simultaneously in atmospheric aerosols34 and little attention has been
63
paid to the atmospheric processes of proteinaceous matter in aerosols.
marine11, 28-34 and even polar regions.35, 36 Till now, few studies have focused on both
64
Previous studies also investigated the seasonal variations of proteins/FAAs in
65
aerosols.14, 17, 19-21, 23, 25 It was observed that higher concentrations of proteins/FAAs in 5 ACS Paragon Plus Environment
Environmental Science & Technology
Page 6 of 33
66
warm seasons (i.e., spring and summer) than those in cold seasons (i.e., autumn and
67
winter) in Iowa,19 Arizona,20 North Carolina,17 and Roma,23 and in contrast,
68
enhancements of proteins/FAAs were observed in cold seasons in China.14, 21,
69
different seasonal patterns can be affected by different sources and, possibly,
70
environmental behaviors in different regions. Primary biological aerosol particles are
71
suggested as one of the major sources of aerosol proteinaceous matter in the
72
atmosphere.10 Anthropogenic activities can also be the sources of aerosol proteinaceous
73
matter, e.g., soil resuspension from traffic and construction, crop cultivation and biomass
74
burning.4, 14 Mopper and Zika37 proposed that, in the atmosphere, degradation of high
75
molecular weight (HMW) proteinaceous matter could be a source of low molecular
76
weight (LMW) FAAs. Recently, the release of FAAs upon the oxidation of proteins and
77
peptides with hydroxyl radicals (·OH) in aqueous phase has been observed in a
78
laboratory study.38 However, the release of FAAs from HMW proteinaceous matter has
79
not been observed in ambient environment.
25
The
80
As one of the most rapidly economic developing regions in China, the Pearl River
81
Delta region (PRDR) is densely populated and economically developed, with high levels
82
of particulate pollution as well as high levels of ozone (O3) and other pollutants.39
83
Meanwhile, this region is of subtropical humid monsoonal climate40 and the condition is
84
suitable for plants growing and proteinaceous matter releasing throughout the year. The
85
region is ideal to reveal the atmospheric interaction between natural emissions and
86
atmospheric pollutants, which is focused on in this study. 6 ACS Paragon Plus Environment
Page 7 of 33
Environmental Science & Technology
87
Here, we present a one-year observation of both proteins and FAAs in fine particulate
88
matter (PM2.5) at Tianhu, Guangzhou, a regional site of the PRDR. The objectives of this
89
work are: (1) to measure the concentration levels and seasonal cycles of proteins and
90
FAAs in PM2.5; (2) to investigate the sources of aerosol proteins and FAAs; (3) to
91
understand the occurrence and atmospheric processes of aerosol proteinaceous matter in
92
ambient environment, especially the release of FAAs upon the oxidation of proteins and
93
peptides. The results may help to improve the current understanding of sources,
94
atmospheric processes and fates of aerosol proteinaceous matter in the atmosphere.
95 96
2. MATERIALS AND METHODS
97
2.1 Sample Collection. PM2.5 samples were collected at Tianhu, Guangzhou (23.65 oN,
98
113.63 oE, Figure S1) from March 2012 to February 2013. The sampling site is one of the
99
national monitoring stations in the PRDR with continuous measurements of air pollutants
100
(e.g., SOx, NOx, O3), which is ideal for observation of atmospheric processes.41, 42 Filter
101
samples were collected every six days with a duration of 24 h on PTFE filters and
102
prebaked quartz fiber filters (550 oC, 10 h) using a mini volume sampler (5 L min-1,
103
Airmetrics, US) and a medium volume sampler (300 L min-1, Minye, China), respectively.
104
A total of 52 PTFE filters and 51 quartz filter samples were obtained for proteinaceous
105
matter and other chemical components analyses.
106
2.2 Protein and Free Amino Acid Analyses. A part of each filter sample (~60 m3 of
107
air) was ultrasonically extracted twice for 30 min in an ice bath with 6 mL and 4 mL of 7 ACS Paragon Plus Environment
Environmental Science & Technology
108
autoclaved Milli-Q water (18.2 MΩ cm). The extract solutions were combined and
109
filtered through a syringe filter (0.45 µm cellulose acetate membrane, Thermo, US). The
110
filtered extracts were lyophilized and redissolved in autoclaved Milli-Q water for the
111
following protein and FAA analyses.
112
An aliquot of 500 µL was taken for protein analysis with a bicinchoninic acid assay
113
(BCA, Micro BCA Protein Assay Kit, Thermo, US).4, 6, 14, 19, 43 Before BCA analysis, the
114
sample extract was subjected to size-exclusion column (PD MiniTrapTM G-25, GE
115
Healthcare, US) to remove possible interfering substances including proteinaceous matter
116
of molecular mass (MW) smaller than 5 kDa, such as FAAs and some peptides. Then the
117
proteinaceous matter of the purified sample (MW > 5 kDa) was determined with BCA
118
assay. The assay was performed in microwell plates (96 wells, Corning, US) and
119
calibrated with aqueous standard solution of bovine serum albumin (BSA, in Assay Kit).
120
The other aliquot (300 µL) of the redissolved sample were again lyophilized and
121
redissolved with 100 µL of 0.1 N HCl for the FAA analysis. Free amino acids were
122
determined by high-performance liquid chromatography (HPLC) with a pre-column
123
derivatization using o-phthalaldehyde (OPA) and 9-fluorenylmethyl chloroformate
124
(FMOC).44 The applied HPLC system (Agilent 1260, Germany) consists of a quaternary
125
pump (G1311C), an auto-sampler (G1329B) and a fluorescence detector (G1321C, λex =
126
330 nm and λem = 420 nm). Chromatographic separation of FAAs’ derivatives was
127
performed with a Zorbax Eclipse-AAA column (4.6×150 mm, 5 µm) at 40 oC, and a
128
typical chromatogram for AA standard solution is shown in Figure S2. 8 ACS Paragon Plus Environment
Page 8 of 33
Page 9 of 33
Environmental Science & Technology
129
As detailed in Table S1, the method detection limit (MDL, 3 s method, n = 5) for
130
proteins was 1.08 µg mL-1 and the corresponding effective limit in the aerosol samples
131
(EMDL) was 0.03 µg m-3, with a precision of ~2%. The MDLs of the investigated
132
individual AAs (i.e., aspartic acid (Asp), glutamic acid (Glu), asparagine (Asn), serine
133
(Ser), glutamine (Gln), histidine (His), glycine (Gly), threonine (Thr), arginine (Arg),
134
alanine (Ala), tyrosine (Tyr), valine(Val), methionine (Met), tryptophane (Trp),
135
phenylalanine (Phe), isoleucine (Ile), leucine (Leu) and lysine (Lys)) ranged from 0.04 µg
136
mL-1 for Val to 1.98 µg mL-1 for Gln, and their EMDLs were from 6.9×10-4 to 0.03 µg
137
m-3. The precisions of the investigated AAs were all less than 10%. Measurement results
138
for field blank filter samples were below the MDLs. To test the recoveries of the
139
extraction method, standard solutions (BSA and AAs) were spiked onto the blank filters.
140
The recovery of BSA was 67.0%, and those of the individual AAs ranged from 62.6% for
141
Met to 79.4% for Ser (Table S1). The lower recoveries than previous studies27, 45, 46 can
142
be influenced by the high protein absorption of quartz fiber filters.
143
2.3 Other Chemical Components Analyses. The mass concentrations of PM2.5 were
144
determined by scaling the mass differences of PTFE filters before and after sample
145
collection with an electronic microbalance (± 0.001 mg, Sartorius MC5, Germany) and
146
the sample volumes (~7.2 m3). Elemental carbon (EC) and organic carbon (OC) were
147
analyzed by an OC/EC analyzer (Sunset Laboratory, US) using the thermo-optical
148
transmittance (TOT) method (NIOSH protocol). Water-soluble ions (Na+, NH4+, K+, Cl-,
149
NO3- and SO42-) were measured by ion chromatography (DX90, Dionex, US). Elements 9 ACS Paragon Plus Environment
Environmental Science & Technology
150
including Al, Si, S, Cl, K, Ca, Ti, Mn, Fe, Cu, Zn, Br, and Pb were measured by X-ray
151
fluorescence spectrometry (XRF, Epsilon5, PANalytical, the Netherlands). More details
152
of the chemical components analyses and their concentrations refer to Table S2 and our
153
previous publication.41
154
2.4 Auxiliary Data. The meteorological data (e.g., temperature, precipitation, visibility
155
and wind speed) during the sampling period were obtained from Weather Underground
156
(http://www.wunderground.com/). Correlation analysis was performed with SPSS
157
software (IBM SPSS Statistics 20). The hourly ozone (O3) concentration data were
158
obtained from Guangdong Environmental Monitoring Center and 24 h integration of O3
159
was obtained for further analysis.
160 161
3. RESULTS AND DISCUSSION
162
3.1 Concentrations of Proteinaceous Matter. Proteins (MW > 5 kDa) and 15 AAs,
163
i.e., Asp, Glu, Asn, Ser, Gln, His, Gly, Thr, Arg, Ala, Tyr, Val, Met, Phe and Lys, were
164
detected in our samples. As shown in Table 1, the annual protein concentrations ranged
165
from 0.20 to 1.86 µg m-3 with an average of 0.79 ± 0.47 µg m-3, and the concentrations of
166
total FAAs were from 0.06 to 0.28 µg m-3 (average: 0.13 ± 0.05 µg m-3).
167
Table 2 gives an overview of proteins and total FAAs in particulate matter with
168
different size ranges (i.e., total suspended particle (TSP), coarse particulate matter (PM10)
169
and PM2.5) detected in different regions. Limited studies have reported the data of
170
proteins in PM2.5 with variable concentration levels ranging from < MDLs to 7.20 µg m-3 10 ACS Paragon Plus Environment
Page 10 of 33
Page 11 of 33
Environmental Science & Technology
171
in different regions.16-18, 20 It is worth noting that much higher protein levels (2.08–36.7
172
µg m-3) determined by BCA method were observed in Hefei, China.14 The discrepancy
173
could be derived from the removal of LMW interfering substances before BCA analysis.
174
It has been suggested that some LMW substances may react with BCA reagents, such as
175
humic acid and glucose.47, 48 Size-exclusion column is suitable for removing interferences
176
such as soot, ammonium sulfate and humic like substances (HULIS), and most
177
importantly, FAAs,6, 49 which were also analyzed in this study.
178
The concentrations of total FAAs in our observation were comparable to those
179
observed in PM2.5 in continental regions, such as urban/suburban areas of Xi’an,21
180
Nanjing24 and Hong Kong,25 and rural areas of California27, 46 and North Carolina.22, 45 In
181
contrast, lower concentrations have been found in most of the marine and polar regions,
182
such as the Atlantic Ocean (cruise campaign),11 the North Pacific Ocean (cruise
183
campaign),33 the Mediterranean (Finokalia station)34 and the Arctic (Svalbard islands).36
184
The concentrations of FAAs in coastal region increased under the continental influence
185
such as the results from coastal Qingdao and the Yellow Sea, indicating the significant
186
contribution of continental sources.29
187
Proteins and total FAAs contributed 1.9% (0.6–3.7%) and 0.3% (0.2–0.6%) to PM2.5,
188
respectively (Table 1). The results are comparable to the reported contributions of
189
proteinaceous matter to PM2.5 in previous studies: for proteins, the contributions of 2.0%
190
in urban Munich6 and 0–1.5% in North Carolina;17 for FAAs, the contribution of 0.7–1.0%
191
in urban Roma.23 11 ACS Paragon Plus Environment
Environmental Science & Technology
192
3.2 Compositions of Free Amino Acids. Among the investigated FAAs, Gly was the
193
most abundant FAA species, contributing 19.9% to the total FAAs (Figure 1).
194
Subsequently, Val, Met and Phe accounted for 18.5%, 16.1% and 13.5% of the total
195
FAAs, respectively. The minor species, such as Lys, Thr, Ser, Ala, Arg and Glu,
196
contributed 2.5–7.9% and the other five ones, i.e., Asn, Gln, Asp, Tyr and His, together
197
accounted for only 8.1% of the total FAAs. As shown in previous studies, the
198
compositions of ambient FAAs varied among different locations. In the Chinese cities of
199
Nanjing and Xi’an, Gly, Cys, Val and Ala were observed as the dominant FAAs in
200
urban/suburban aerosols,21, 24 while, in North Carolina, Gly, Ala, Asp and Arg were the
201
major species.22,
202
species in aerosols.35, 36
45
In polar regions, Gly, Ser and Arg were the most abundant FAA
203
In general, Gly has been found as a dominant species in many locations.21, 22, 28, 33, 34, 36
204
Its high levels in aerosols could be due to the ubiquity of Gly in the environment, which
205
is a fundamental component of the most abundant fibrous proteins in animals
206
(collagen).50 Other Gly-rich proteins such as elastin and certain keratins (e.g., silk
207
fibroins) also exist commonly in the nature, which may partially explain the high
208
occurrence of Gly.22 Moreover, the high abundance of Gly may also be attributed to its
209
low photochemical reactivity with a half-life longer than 2000 h in aqueous phase.51 Phe
210
had an intermediate reactivity with a half-life of 21 h.51 Met is a common constituent of
211
proteins in all organisms, but can be oxidized to methionine sulfoxide easily by O3 with a
212
half-life less than 2.5 h.36,
51
Thus, the high distribution of Met in Tianhu and its 12
ACS Paragon Plus Environment
Page 12 of 33
Page 13 of 33
213
Environmental Science & Technology
instability indicate a possible local source of this AA.
214
3.3 Seasonal Trends of Proteinaceous Matter. Figure 2 shows the temporal variations
215
of PM2.5, proteins, total FAAs and other chemical species including OC, EC, and
216
water-soluble ions at Tianhu. Ozone and metrological data were also displayed in the
217
same figure. The concentrations of proteins and total FAAs peaked in October, and
218
reached minimums in July and December, respectively.
219
Proteins and total FAAs showed similar temporal trends with O3, PM2.5 and its major
220
chemical components (e.g., OC, EC, SO42-, NH4+ and K+). The highest protein level on
221
average was found in autumn (Sep.–Nov.), followed by winter (Dec.–Feb.), summer
222
(Jun.–Aug.) and spring (Mar.–May). As shown in Figure 2a and 2e, the concentrations of
223
proteinaceous matter were highly sensitive to rainfall events. The averaged protein
224
content in the rainy period (Apr.–mid-Sep., 0.52 ± 0.30 µg m-3) was only half of that in
225
the dry period (1.02 ± 0.47 µg m-3), similar to the results reported in Mexico City12 and
226
Hefei.14 The discrepancy is ascribed to the wet deposition in rainy period and the
227
aerosolization of dry soils during dry period.14 The contributions of proteins to PM2.5
228
were observed slightly lower in spring (1.7%) and summer (1.8%) than those in autumn
229
(1.9%) and winter (2.3%). It suggests the importance of wet deposition on the occurrence
230
of aerosol proteinaceous matter in the PRDR (Figure 2).
231
Total FAAs showed similar seasonal variation to that of proteins with the highest
232
seasonal average in autumn, followed by winter, summer and spring. The concentrations
233
of total FAAs in the rainy period (0.10 ± 0.03 µg m-3) were also lower than that in the dry 13 ACS Paragon Plus Environment
Environmental Science & Technology
234
period (0.14 ± 0.05 µg m-3), again showing the influence of wet deposition. Enhancement
235
of total FAAs in autumn was also observed in the previous observations in two Chinese
236
cities, Hong Kong25 and Xi’an.21 Gly, Val, Met, Phe, Lys, Arg, Ala and Thr were found
237
with higher concentrations in autumn than those in the other seasons (Table 1), but the
238
minorities (i.e., Glu, Asn, Gln, His and Tyr) had relatively constant concentrations
239
throughout the year. Constant contributions of total FAAs to PM2.5 were also observed
240
during the sampling period (~0.3%).
241
The enhancements of proteins and most FAAs in autumn could be due to the
242
biomass/biofuel burning in this region (e.g., straw burning in harvest season and other
243
burning activities).52 This is inferred by the highest seasonal K+ concentration and OC/EC
244
ratio observed in autumn at this site.41 However, the contributions of other sources to
245
proteinaceous matter could not be ruled out considering the co-enhancements of NH4+,
246
SO42- and soil-related elements. The high levels of O3 in autumn (Figure 2b) may also
247
lead to enhanced photochemical release of FAAs via the degradation of proteins (see
248
more discussion in Section 3.5).51, 53
249
3.4 Source Analysis. Aerosol proteinaceous matter could be primarily derived from
250
biogenic activities, biomass burning, and agricultural activities.10, 14, 54 Free amino acids
251
in aerosols might be secondarily produced by direct photolysis (UV radiation),
252
photochemical hydrolysis (oxidative attack of ·OH or O3) and enzyme-based hydrolysis
253
of HMW proteinaceous matter.37,
254
between proteins and total FAAs (r = 0.74, p < 0.01). Dominant FAA species e.g., Gly,
53
In this study, significant correlation was found
14 ACS Paragon Plus Environment
Page 14 of 33
Page 15 of 33
Environmental Science & Technology
255
Val and Ala, also showed strong correlations with proteins (r = 0.70–0.81, p < 0.01). It
256
suggests that proteins and FAAs might have common sources/related processes. In order
257
to understand their source contributions, correlation analysis and positive matrix
258
factorization (PMF) analysis between proteinaceous matter and other major chemical
259
components in PM2.5 (i.e., OC, EC, water-soluble ions and elements) were investigated
260
(Table S3 and Figure S3).
261
Both proteins and total FAAs showed significant correlations with NH4+ (r = 0.74 and
262
0.80, respectively, p < 0.01), which was also observed in previous studies,55, 56 suggesting
263
similar sources and sinks of these nitrogen species. NH4+ in the atmosphere, the
264
protonation product of NH3, is tightly related to the processes of livestock excreta and
265
fertilizer application,57,
266
organic nitrogen.59 Therefore, these activities could be the sources of aerosol
267
proteinaceous matter in this study, which is the dominant contributor to proteinaceous
268
matter, contributed 48.8% for proteins and 41.4% for total FAAs, respectively (Details of
269
PMF analysis see SI). The production from photochemical decomposition of dissolved
270
humic materials can be another possible source, which has already been reported as a
271
source of FAAs and NH4+.60 Additionally, urea cycle of organisms could be the other
272
source of proteinaceous matter, suggested by the significant correlation between NH4+
273
and Arg (r = 0.71, p < 0.01), an AA tightly connected with urea cycle.61
274
58
which have been suggested as the sources of atmospheric
In our observation, proteins and total FAAs were well correlated with non-sea salt
15 ACS Paragon Plus Environment
Environmental Science & Technology
275
potassium (r = 0.79 and 0.69, respectively, p < 0.01, nss-K+ = K+ - 0.037 × Na+), a
276
commonly used tracer of biomass burning.52, 62 It suggests that biomass burning, which
277
has been reported previously to release bio-molecules, such as cholesterol, proteins and
278
AAs,14, 36, 63 was an important source of aerosol proteinaceous matter at this site. The
279
contributions of biomass burning to the measured proteins and total FAAs were 21.0%
280
and 28.9%, respectively (Details of PMF analysis see SI).
281
The correlations between proteinaceous matter and crustal materials (CM) have also
282
been found, pointing to the influence of soil related activities. CM was calculated as
283
below:41 CM = 2.20Al + 2.49Si + 1.63Ca + 2.42Fe + 1.94[Ti] (1)
284
Fair correlation was observed between total FAAs and CM (r = 0.52, p < 0.01), while
285
significant correlation between proteins and CM (r = 0.73, p < 0.01) was found. Soil and
286
fugitive dust were found to contain proteinaceous matter, such as pollens and pollen
287
fragments, animal dander and molds,4 which can be the source of aerosol proteinaceous
288
matter. Soil from the nearby wooden and agricultural fields may release organic nitrogen
289
in the form of proteinaceous matter into the atmosphere. The contributions of fugitive
290
dust/soil to proteins differed significantly from it to total FAAs (proteins: 26.7%, total
291
FAAs: 7.0%) (Details of PMF analysis see SI), which may be due to the polymeric state
292
of organic nitrogen in soil (e.g, peptides, proteins and protein-humic complex).48, 64
293
3.5 Atmospheric Degradation of Proteinaceous Matter. As shown in Figure 3a and
294
3b, we found that both proteins and total FAAs showed significant correlations with O3 (r 16 ACS Paragon Plus Environment
Page 16 of 33
Page 17 of 33
Environmental Science & Technology
295
= 0.63 and 0.70, respectively, p < 0.01). It suggests that proteinaceous matter may be
296
involved in O3 related processes. Previous studies have shown that O3 may promote the
297
release of proteinaceous matter from suspending plant material (e.g., pollen), leading to
298
the increasing levels of biological aerosols.65, 66 Additionally, O3 can also induce chemical
299
modifications of proteinaceous matter via protein oxidation, nitration and oligomerization,
300
which may promote the allergic potential of proteinaceous matter.67-71 Moreover, HMW
301
proteinaceous matter under the influence of O3 could also be degraded into LMW
302
proteinaceous matter (i.e., LMW proteins, peptides and FAAs) to have possible impacts
303
on nitrogen cycle.37, 51, 53
304
In our study, more significant correlations were observed for [FAAs] and [Gly] with
305
[O3][Proteins] (r = 0.83 and 0.90, respectively, p < 0.01) than with [O3] (r = 0.70 and 0.74,
306
respectively, p < 0.01) (Figure 3c and 3d), indicating that O3 related degradation of
307
proteins may happen and lead to the formation of FAAs. Free amino acids, especially Gly,
308
have been reported to be preferentially released from the model proteins upon the
309
oxidation by ·OH in aqueous phase.38 A similar process between proteins and FAAs may
310
occur under the influence of O3 in the atmosphere. Moreover, a series of previous
311
experimental studies have demonstrated that the reactions between proteins and
312
atmospheric oxidants including O3, NO2, and ·OH are second-order.38, 67, 68, 70, 72, 73 Thus,
313
the production of FAAs and Gly would be characterized as a second-order reaction
314
dependent on the concentrations of precursor proteins/peptides and O3. The possible
315
reaction mechanism can be expressed as follow: 17 ACS Paragon Plus Environment
Environmental Science & Technology
Page 18 of 33
Proteins/Peptides(HMW) + O3 → Proteins/Peptides (LMW) + FAAs (αGly + …) (2) d[AAs] = αkProtein [O3 ] (3) dt 316
where k is second-order rate coefficient and α is stoichiometric coefficient. Thus, the
317
slope of the fitted lines in Figure 3c and 3d would correspond to αk∆t. Previous studies of
318
kinetic experiments have reported that k is in the order of 10-15–10-14 cm3 s-1.67,
319
Assuming the typical atmospheric reaction time (∆t) of 2–3 h, α can be estimated to be
320
3×10-4–3×10-3 for FAAs and 10-4–10-3 for Gly, respectively. These α values are slightly
321
lower than the previously estimated α for the degradation of tripeptides (10-3–7×10-2)
322
by ·OH in aqueous phase.38 This seems reasonable as proteins are larger molecules
323
compared to tripeptides and O3 is a weaker oxidant than ·OH, so that lower α values are
324
expected.
68
325
This proposed mechanism provides a new insight into the transformation of aerosol
326
proteinaceous matter in the atmosphere. Although the kinetics of protein/peptide
327
degradation upon O3 cannot be explicitly demonstrated in our observation, the importance
328
of atmospheric oxidant on the existence of proteinaceous matter in the atmosphere should
329
be highlighted. Reactions of proteinaceous matter with some air pollutants (e.g., O3 and
330
NOx) have received considerable amount of attention, which can alter the physical,
331
chemical and biological properties of proteinaceous matter.67-69, 74 Besides, ·OH can be
332
quickly produced with the photolysis of O3 by solar UV radiation in the atmosphere.75
333
Thus, the degradation mechanisms of proteinaceous matter with O3 may contain a
334
number of reaction pathways and should be further studied in field measurements and 18 ACS Paragon Plus Environment
Page 19 of 33
335
Environmental Science & Technology
laboratory simulations.
336
Furthermore, the release of FAAs via the atmospheric processes of HMW
337
proteinaceous matter may have an implication on the bioavailability of atmospheric
338
organic nitrogen. It is believed that proteins are not directly avaliable to plants except in
339
some special conditions, such as the symbiosis with fungi, the exudation of proteolytic
340
enzymes from roots and the endocytosis of root cells.76, 77 However, airborne FAAs are
341
particularly bioavailable upon deposition and play important roles on ecological
342
processes and plant nutrition.36,
343
generated from the degradation of HMW proteins by O3 in ambient environment. This
344
may improve the bioavailability of HMW proteinaceous matter and promote nitrogen
345
utilization in ecosystem. Although some studies have focused on the nitration and
346
oligomerization modification of proteins by air pollutants,6-9, 68 little is known about the
347
degradation of proteins/peptides in the atmosphere. Further kinetic studies of
348
protein/peptide degradation by atmospheric oxidants (e.g., O3 and ·OH) in the ambient
349
environment should be conducted to reveal the atmospheric degradation processes of
350
proteinaceous matter.
37, 46
Our observation suggests that FAAs could be
351 352
ASSOCIATED CONTENT
353
Supporting Information
354
The supporting information includes: details of PMF analysis information, quality
355
assurance of AA analysis, seasonal mass concentration of PM2.5 and the associated 19 ACS Paragon Plus Environment
Environmental Science & Technology
356
chemical components, molar and mass concentrations of proteins and FAAs, correlation
357
coefficients of proteinaceous matter and major ions as well as CM, location of the
358
sampling site, a typical chromatogram of AA standard solution and the PMF results.
359 360
AUTHOR INFORMATION
361
*Corresponding Author
362
phone: +86-135-7097-4216; e-mail:
[email protected].
363
phone: +86-156-9242-3889; e-mail:
[email protected].
364 365
Notes
366
The authors declare no competing financial interest.
367 368
ACKNOWLEDGMENTS
369
This work is supported by the National Natural Scientific Foundation of China (Grant No.
370
41105084 and 41675119) and the joint project of Guangdong-National Natural Science
371
Foundation of China (Grant No. U1033301). We thank Prof. Jianzhen Yu from Hong
372
Kong University of Science and Technology for the measurement of elements. S.L. and
373
F.L. thank the support of the Chinese Scholarship Council (CSC).
374 375
REFERENCES
376 377
(1) Pöschl, U., Atmospheric Aerosols: Composition, Transformation, Climate and Health Effects. Angew. Chem. Int. Ed. 2005, 44 (46), 7520-7540; DOI: 10.1002/anie.200501122.
20 ACS Paragon Plus Environment
Page 20 of 33
Page 21 of 33
378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418
Environmental Science & Technology
(2) Mikhailov, E. F.; Vlasenko, S. S.; Niessner, R.; Pöschl, U., Interaction of aerosol particles composed of protein and salts with water vapor: hygroscopic growth and microstructural rearrangement. Atmos. Chem. Phys. 2004, 4 (1), 323-350; DOI: 1680-7324/acp-4-323-2004. (3) Ariya, P. A.; Sun, J.; Eltouny, N. A.; Hudson, E. D.; Hayes, C. T.; Kos, G., Physical and chemical characterization of bioaerosols - Implications for nucleation processes. Int. Rev. Phys. Chem. 2009, 28 (1), 1-32; DOI: 10.1080/01442350802597438. (4) Miguel, A. G.; Cass, G. R.; Glovsky, M. M.; Weiss, J., Allergens in paved road dust and airborne particles. Environ. Sci. Technol. 1999, 33 (23), 4159-4168; DOI: 10.1021/es9904890. (5) Douwes, J.; Thorne, P. S.; Pearce, N.; Heederik, D., Bioaerosol Health Effects and Exposure Assessment:
Progress
and
Prospects.
Ann.
Occup.
Hyg.
2003,
47
(3),
187-200;
DOI:
10.1093/annhyg/meg032. (6) Franze, T.; Weller, M. G.; Niessner, R.; Pöschl, U., Protein nitration by polluted air. Environ. Sci. Technol. 2005, 39 (6), 1673-1678; DOI: 10.1021/es0488737. (7) Gruijthuijsen, Y. K.; Grieshuber, I.; Stocklinger, A.; Tischler, U.; Fehrenbach, T.; Weller, M. G.; Vogel, L.; Vieths, S.; Pöschl, U.; Duschl, A., Nitration enhances the allergenic potential of proteins. Int. Arch. Allergy. Immun. 2006, 141 (3), 265-275; DOI: 10.1159/000095296. (8) Yang, H.; Zhang, Y.; Pöschl, U., Quantification of nitrotyrosine in nitrated proteins. Anal. Bioanal. Chem. 2010, 397 (2), 879-886; DOI: 10.1007/s00216-010-3557-3. (9) Zhang, Y. Y.; Yang, H.; Pöschl, U., Analysis of nitrated proteins and tryptic peptides by HPLC-chip-MS/MS: site-specific quantification, nitration degree, and reactivity of tyrosine residues. Anal. Bioanal. Chem. 2011, 399 (1), 459-471; DOI: 10.1007/s00216-010-4280-9. (10) Matos, J. T. V.; Duarte, R. M. B. O.; Duarte, A. C., Challenges in the identification and characterization of free amino acids and proteinaceous compounds in atmospheric aerosols: A critical review. TrAC, Trends Anal. Chem. 2016, 75, 97-107; DOI: 10.1016/j.trac.2015.08.004. (11) Wedyan, M. A.; Preston, M. R., The coupling of surface seawater organic nitrogen and the marine aerosol as inferred from enantiomer-specific amino acid analysis. Atmos. Environ. 2008, 42 (37), 8698-8705; DOI: 10.1016/j.atmosenv.2008.04.038. (12) Rosas, I.; Yela, A.; Salinas, E.; Arreguin, R.; Rodriguez-Romero, A., Preliminary assessment of protein associated with airborne particles in Mexico City. Aerobiologia 1995, 11 (2), 81-86; DOI: 10.1007/bf02738271. (13) Gutiérrez-Castillo, M. E.; Olivos-Ortiz, M.; De Vizcaya-Ruiz, A.; Cebrián, M. E., Chemical characterization of extractable water soluble matter associated with PM10 from Mexico City during 2000. Chemosphere 2005, 61 (5), 701-710; DOI: 10.1016/j.chemosphere.2005.03.063. (14) Kang, H.; Xie, Z.; Hu, Q., Ambient protein concentration in PM10 in Hefei, central China. Atmos. Environ. 2012, 54, 73-79; DOI: 10.1016/j.atmosenv.2012.03.003. (15) Staton, S. J. R.; Woodward, A.; Castillo, J. A.; Swing, K.; Hayes, M. A., Ground level environmental protein concentrations in various ecuadorian environments: Potential uses of aerosolized protein for ecological research. Ecol. Indic. 2015, 48, 389-395; DOI: 10.1016/j.ecolind.2014.08.036. (16) Chen, Q.; Hildemann, L. M., Size-Resolved Concentrations of Particulate Matter and Bioaerosols Inside
versus
Outside
of
Homes.
Aerosol
Sci.
Technol.
2009,
10.1080/02786820902882726.
21 ACS Paragon Plus Environment
43
(7),
699-713;
DOI:
Environmental Science & Technology
419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459
Page 22 of 33
(17) Menetrez, M. Y.; Foarde, K. K.; Dean, T. R.; Betancourt, D. A.; Moore, S. A., An evaluation of the protein
mass
of
particulate
matter.
Atmos.
Environ.
2007,
41
(37),
8264-8274;
DOI:
10.1016/j.atmosenv.2007.06.021. (18) Menetrez, M. Y.; Foarde, K. K.; Esch, R. K.; Schwartz, T.; Dean, T. R.; Hays, M. D.; Cho, S. H.; Betancourt, D. A.; Moore, S., An evaluation of indoor and outdoor biological particulate matter. Atmos. Environ. 2009, 43 (34), 5476-5483; DOI: 10.1016/j.atmosenv.2009.07.027. (19) Rathnayake, C. M.; Metwali, N.; Baker, Z.; Jayarathne, T.; Kostle, P. A.; Thorne, P. S.; Oshaughnessy, P. T.; Stone, E. A., Urban Enhancement of PM10 Bioaerosol Tracers Relative to Background Locations in the Midwestern United States. J. Geophys. Res. 2016, 121 (9), 5071-5089; DOI: 10.1002/2015jd024538. (20) Boreson, J.; Dillner, A. M.; Peccia, J., Correlating bioaerosol load with PM2.5 and PM10cf concentrations: a comparison between natural desert and urban-fringe aerosols. Atmos. Environ. 2004, 38 (35), 6029-6041; DOI: 10.1016/j.atmosenv.2004.06.040. (21) Ho, K. F.; Ho, S. S. H.; Huang, R.; Liu, S. X.; Cao, J.; Zhang, T.; Chuang, H. C.; Chan, C. S.; Hu, D.; Tian, L., Characteristics of water-soluble organic nitrogen in fine particulate matter in the continental area of China. Atmos. Environ. 2015, 106, 252-261; DOI: 10.1016/j.atmosenv.2015.02.010. (22) Samy, S.; Robinson, J.; Rumsey, I. C.; Walker, J. T.; Hays, M. D., Speciation and trends of organic nitrogen in southeastern US fine particulate matter (PM2.5). J. Geophys. Res. 2013, 118 (4), 1996-2006; DOI: 10.1029/2012jd017868. (23) Di Filippo, P.; Pomata, D.; Riccardi, C.; Buiarelli, F.; Gallo, V.; Quaranta, A., Free and combined amino acids in size-segregated atmospheric aerosol samples. Atmos. Environ. 2014, 98, 179-189; DOI: 10.1016/j.atmosenv.2014.08.069. (24) Yang, H.; Yu, J. Z.; Ho, S. S. H.; Xu, J.; Wu, W.-S.; Wan, C. H.; Wang, X.; Wang, X.; Wang, L., The chemical composition of inorganic and carbonaceous materials in PM2.5 in Nanjing, China. Atmos. Environ. 2005, 39 (20), 3735-3749; DOI: 10.1016/j.atmosenv.2005.03.010. (25) Yu, J. Z.; Schauer, J., Chemical characterization of water soluble organic compounds in particulate matters in Hong Kong. In Report from Hong Kong Environmental Protection Department, 2002. (26) Mace, K. A.; Artaxo, P.; Duce, R. A., Water-soluble organic nitrogen in Amazon Basin aerosols during the dry (biomass burning) and wet seasons. J. Geophys. Res. 2003, 108 (D16), 1-14; DOI: 10.1029/2003jd003557. (27) Zhang, Q.; Anastasio, C.; Jimemez-Cruz, M., Water-soluble organic nitrogen in atmospheric fine particles (PM2.5) from Northern California. J. Geophys. Res. 2002, 107 (D11), 1-9; DOI: 10.1029/2001jd000870. (28) Barbaro, E.; Zangrando, R.; Moret, I.; Barbante, C.; Cescon, P.; Gambaro, A., Free amino acids in atmospheric particulate matter of Venice, Italy. Atmos. Environ. 2011, 45, 5050-5057; DOI: 10.1016/j.atmosenv.2011.01.068. (29) Shi, J.; Gao, H.; Qi, J.; Zhang, J.; Yao, X., Sources, compositions, and distributions of water‐soluble organic nitrogen in aerosols over the China Sea. J. Geophys. Res. 2010, 115, 1-13; DOI: 10.1029/2009jd013238. (30) Yang, H.; Xu, J.; Wu, W.; Wan, C. H.; Yu, J. Z., Chemical Characterization of Water-Soluble Organic Aerosols at Jeju Island Collected During ACE-Asia. Environ. Chem. 2004, 1 (1), 13-17; DOI: 10.1071/en04006.
22 ACS Paragon Plus Environment
Page 23 of 33
460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500
Environmental Science & Technology
(31) Mace, K. A.; Duce, R. A.; Tindale, N. W., Organic nitrogen in rain and aerosol at Cape Grim, Tasmania, Australia. J. Geophys. Res. 2003, 108 (D11), 1-14; DOI: 10.1029/2002jd003051. (32) Mace, K. A.; Kubilay, N.; Duce, R. A., Organic nitrogen in rain and aerosol in the eastern Mediterranean atmosphere: An association with atmospheric dust. J. Geophys. Res. 2003, 108 (D10), 1-11; DOI: 10.1029/2002JD002997. (33) Matsumoto, K.; Uematsu, M., Free amino acids in marine aerosols over the western North Pacific Ocean. Atmos. Environ. 2005, 39 (11), 2163-2170; DOI: 10.1016/j.atmosenv.2004.12.022. (34) Mandalakis, M.; Apostolaki, M.; Tziaras, T.; Polymenakou, P.; Stephanou, E. G., Free and combined amino acids in marine background atmospheric aerosols over the Eastern Mediterranean. Atmos. Environ. 2011, 45 (4), 1003-1009; DOI: 10.1016/j.atmosenv.2010.10.046. (35) Barbaro, E.; Zangrando, R.; Vecchiato, M.; Piazza, R.; Cairns, W. R. L.; Capodaglio, G.; Barbante, C.; Gambaro, A., Free amino acids in Antarctic aerosol: potential markers for the evolution and fate of marine aerosol. Atmos. Chem. Phys. 2015, 15 (10), 5457-5469; DOI: 10.5194/acp-15-5457-2015. (36) Scalabrin, E.; Zangrando, R.; Barbaro, E.; Kehrwald, N. M.; Gabrieli, J.; Barbante, C.; Gambaro, A., Amino acids in Arctic aerosols. Atmos. Chem. Phys. 2012, 12 (21), 10453-10463; DOI: 10.5194/acp-12-10453-2012. (37) Mopper, K.; Zika, R. G., Free amino acids in marine rains: evidence for oxidation and potential role in nitrogen cycling. Nature 1987, 325 (6101), 246-249; DOI: 10.1038/325246a0. (38) Liu, F.; Lai, S.; Tong, H.; Lakey, P. S. J.; Shiraiwa, M.; Weller, M. G.; Pöschl, U.; Kampf, C. J., Release of free amino acids upon oxidation of peptides and proteins by hydroxyl radicals. Anal. Bioanal. Chem. 2017, 409 (9), 2411-2420; DOI: 10.1007/s00216-017-0188-y. (39) Ling, Z. H.; Zhao, J.; Fan, S. J.; Wang, X. M., Sources of formaldehyde and their contributions to photochemical O3 formation at an urban site in the Pearl River Delta, southern China. Chemosphere 2017, 168, 1293-1301; DOI: j.chemosphere.2016.11.140. (40) Dou, H.; Zhao, X., Climate change and its human dimensions based on GIS and meteorological statistics in Pearl River Delta, Southern China. Meteorol. Appl. 2011, 18 (1), 111-122; DOI: 10.1002/met.219. (41) Lai, S.; Zhao, Y.; Ding, A.; Zhang, Y.; Song, T.; Zheng, J.; Ho, K. F.; Lee, S.-c.; Zhong, L., Characterization of PM2.5 and the major chemical components during a 1-year campaign in rural Guangzhou, Southern China. Atmos. Res. 2016, 167, 208-215; DOI: 10.1016/j.atmosres.2015.08.007. (42) Chen, X.; Lai, S.; Gao, Y.; Zhang, Y.; Zhao, Y.; Chen, D.; Zheng, J.; Zhong, L.; Lee, S.; Chen, B., Reconstructed Light Extinction Coefficients of Fine Particulate Matter in Rural Guangzhou, Southern China. Aerosol Air Qual. Res. 2016, 16 (8), 1981-1990; DOI: 10.4209/aaqr.2016.02.0064. (43) Chen, Q.; Hildemann, L. M., The effects of human activities on exposure to particulate matter and bioaerosols in residential homes. Environ. Sci. Technol. 2009, 43 (13), 4641-4646; DOI: 10.1021/es802296j. (44) Henderson, J.; Ricker, R. D.; Bidlingmeyer, B. A.; Woodward, C., Rapid, accurate, sensitive, and reproducible HPLC analysis of amino acids. Amino acid analysis using Zorbax Eclipse-AAA columns and the Agilent 1100 HPLC. In Agilent Technologies, 2000; Vol. 1100, pp 1-10. (45) Samy, S.; Robinson, J.; Hays, M. D., An advanced LC-MS (Q-TOF) technique for the detection of amino acids
in
atmospheric
aerosols.
Anal.
Bioanal.
Chem.
2011,
10.1007/s00216-011-5238-2.
23 ACS Paragon Plus Environment
401
(10),
3103-3113;
DOI:
Environmental Science & Technology
501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541
Page 24 of 33
(46) Zhang, Q.; Anastasio, C., Free and combined amino compounds in atmospheric fine particles (PM2.5) and fog waters from Northern California. Atmos. Environ. 2003, 37 (16), 2247-2258; DOI: 10.1016/s1352-2310(03)00127-4. (47) Brown, R. E.; Jarvis, K. L.; Hyland, K. J., Protein measurement using bicinchoninic acid: elimination of interfering substances. Anal. Biochem. 1989, 180 (1), 136-139; DOI: 10.1016/0003-2697(89)90101-2. (48) Roberts, P.; Jones, D. L., Critical evaluation of methods for determining total protein in soil solution. Soil Biol. Biochem. 2008, 40 (6), 1485-1495; DOI: 10.1016/j.soilbio.2008.01.001. (49) Liu, F.; Lai, S.; Reinmuthselzle, K.; Scheel, J. F.; Frohlichnowoisky, J.; Despres, V. R.; Hoffmann, T.; Pöschl, U.; Kampf, C. J., Metaproteomic analysis of atmospheric aerosol samples. Anal. Bioanal. Chem. 2016, 408 (23), 1-12; DOI: 10.1007/s00216-016-9747-x. (50) Voet, D.; Voet, J. G.; Pratt, C. W., Fundamentals of Biochemistry. John Wiley & Sons: 2008. (51) McGregor, K. G.; Anastasio, C., Chemistry of fog waters in California's Central Valley: 2. Photochemical transformations of amino acids and alkyl amines. Atmos. Environ. 2001, 35 (6), 1091-1104; DOI: 10.1016/S1352-2310(00)00282-X. (52) Ho, K. F.; Engling, G.; Ho, S. S. H.; Huang, R.; Lai, S.; Cao, J.; Lee, S. C., Seasonal variations of anhydrosugars in PM2.5 in the Pearl River Delta Region, China. Tellus. B 2014, 66, 1-14; DOI: 10.3402/tellusb.v66.22577. (53) Milne, P.; Zika, R., Amino acid nitrogen in atmospheric aerosols: Occurrence, sources and photochemical modification. J. Atmos. Chem. 1993, 16 (4), 361-398; DOI: 10.1007/bf01032631. (54) Scheller, E., Amino acids in dew – origin and seasonal variation. Atmos. Environ. 2001, 35 (12), 2179-2192; DOI: 10.1016/S1352-2310(00)00477-5. (55) Gorzelska, K.; Galloway, J., Amine nitrogen in the atmospheric environment over the North Atlantic Ocean. Global Biogeochem. Cy. 1990, 4 (3), 309-333; DOI: 10.1029/gb004i003p00309. (56) Kieber, R. J.; Long, M. S.; Willey, J. D., Factors influencing nitrogen speciation in coastal rainwater. J. Atmos. Chem. 2005, 52 (1), 81-99; DOI: 10.1007/s10874-005-8354-6. (57) Zhang, Y.; Dore, A. J.; Ma, L.; Liu, X. J.; Ma, W. Q.; Cape, J. N.; Zhang, F. S., Agricultural ammonia emissions inventory and spatial distribution in the North China Plain. Environ. Pollut. 2010, 158 (2), 490-501; DOI: 10.1016/j.envpol.2009.08.033. (58) Zhang, Y.; Luan, S.; Chen, L.; Shao, M., Estimating the volatilization of ammonia from synthetic nitrogenous fertilizers used in China. J. Environ. Manage. 2011, 92 (3),
480-493; DOI:
10.1016/j.jenvman.2010.09.018. (59) Ham, Y. S.; Tamiya, S., Contribution of dissolved organic nitrogen deposition to total dissolved nitrogen deposition under intensive agricultural activities. Water Air Soil Poll. 2006, 178 (1), 5-13; DOI: 10.1007/s11270-006-9109-y. (60) Tarr, M. A.; Wang, W.; Bianchi, T. S.; Engelhaupt, E., Mechanisms of ammonia and amino acid photoproduction from aquatic humic and colloidal matter. Water Res. 2001, 35 (15), 3688-3696; DOI: 10.1016/S0043-1354(01)00101-4. (61) Micallef, B. J.; Shelp, B. J., Arginine Metabolism in Developing Soybean Cotyledons : II. Biosynthesis. Plant Physiol. 1989, 90 (2), 631-634; DOI: 10.1104/pp.90.2.631. (62) Kunwar, B.; Kawamura, K., One-year observations of carbonaceous and nitrogenous components and major ions in the aerosols from subtropical Okinawa Island, an outflow region of Asian dusts. Atmos. Chem.
24 ACS Paragon Plus Environment
Page 25 of 33
542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582
Environmental Science & Technology
Phys. 2014, 14 (1), 1819-1836; DOI: 10.5194/acp-14-1819-2014. (63) Rogge, W. F.; Hildemann, L. M.; Mazurek, M. A.; Cass, G. R.; Simoneit, B. R. T., Sources of fine organic aerosol. 1. Charbroilers and meat cooking operations. Environ. Sci. Technol. 1991, 25 (6), 1112-1125; DOI: 10.1021/es00018a015. (64) Warren, C., Organic N molecules in the soil solution: what is known, what is unknown and the path forwards. Plant Soil 2014, 375 (1-2), 1-19; DOI: 10.1007/s11104-013-1939-y. (65) Mumford, R. A.; Lipke, H.; Laufer, D. A.; Feder, W. A., Ozone-induced changes in corn pollen. Environ. Sci. Technol. 1972, 6 (5), 427-430; DOI: 10.1021/es60064a010. (66) Beck, I.; Jochner, S.; Gilles, S.; Mcintyre, M.; Buters, J. T. M.; Schmidtweber, C. B.; Behrendt, H.; Ring, J.; Menzel, A.; Traidlhoffmann, C., High Environmental Ozone Levels Lead to Enhanced Allergenicity of Birch Pollen. PLOS ONE 2013, 8 (11), 1-7; DOI: 10.1371/journal.pone.0080147. (67) Shiraiwa, M.; Selzle, K.; Yang, H.; Sosedova, Y.; Ammann, M.; Pöschl, U., Multiphase Chemical Kinetics of the Nitration of Aerosolized Protein by Ozone and Nitrogen Dioxide. Environ. Sci. Technol. 2012, 46 (12), 6672-6680; DOI: 10.1021/es300871b. (68) Kampf, C. J.; Liu, F.; Reinmuthselzle, K.; Berkemeier, T.; Meusel, H.; Shiraiwa, M.; Pöschl, U., Protein Cross-Linking and Oligomerization through Dityrosine Formation upon Exposure to Ozone. Environ. Sci. Technol. 2015, 49 (18), 10859-10866; DOI: 10.1021/acs.est.5b02902. (69) Sharma, V. K.; Graham, N. J. D., Oxidation of Amino Acids, Peptides and Proteins by Ozone: A Review. Ozone-Sci. Eng. 2010, 32 (2), 81-90; DOI: 10.1080/01919510903510507. (70) Liu, F.; Lakey, P.; Berkemeier, T.; Tong, H.; Kunert, A. T.; Meusel, H.; Su, H.; Cheng, Y.; Frohlich-Nowoisky, J.; Lai, S.; Weller, M. G.; Shiraiwa, M.; Poschl, U.; Kampf, C. J., Atmospheric protein chemistry influenced by anthropogenic air pollutants: nitration and oligomerization upon exposure to ozone and nitrogen dioxide. Faraday Discuss. 2017, 1-9; DOI: 10.1039/c7fd00005g. (71) Reinmuth-Selzle, K.; Kampf, C. J.; Lucas, K.; Lang-Yona, N.; Fröhlich-Nowoisky, J.; Shiraiwa, M.; Lakey, P. S. J.; Lai, S.; Liu, F.; Kunert, A. T.; Ziegler, K.; Shen, F.; Sgarbanti, R.; Weber, B.; Bellinghausen, I.; Saloga, J.; Weller, M. G.; Duschl, A.; Schuppan, D.; Pöschl, U., Air Pollution and Climate Change Effects on Allergies in the Anthropocene: Abundance, Interaction, and Modification of Allergens and Adjuvants. Environ. Sci. Technol. 2017, 51 (8), 4119-4141; DOI: 10.1021/acs.est.6b04908. (72) Shiraiwa, M.; Ammann, M.; Koop, T.; Poschl, U., Gas uptake and chemical aging of semisolid organic aerosol particles. PNAS 2011, 108 (27), 11003-11008; DOI: 10.1073/pnas.1103045108. (73) Reinmuth-Selzle, K.; Ackaert, C.; Kampf, C. J.; Samonig, M.; Shiraiwa, M.; Kofler, S.; Yang, H.; Gadermaier, G.; Brandstetter, H.; Huber, C. G.; Duschl, A.; Oostingh, G. J.; Pöschl, U., Nitration of the Birch Pollen Allergen Bet v 1.0101: Efficiency and Site-Selectivity of Liquid and Gaseous Nitrating Agents. J. Proteome Res. 2014, 13 (3), 1570-1577; DOI: 10.1021/pr401078h. (74) Lloyd, J. A.; Spraggins, J. M.; Johnston, M. V.; Laskin, J., Peptide ozonolysis: Product structures and relative reactivities for oxidation of tyrosine and histidine residues. J. Am. Soc. Mass. Spectrom. 2006, 17 (9), 1289-1298; DOI: 10.1016/j.jasms.2006.05.009. (75) Guicherit, R.; Roemer, M., Tropospheric ozone trends. Chemosphere 2000, 2 (2), 167-183; DOI: 10.1016/S1465-9972(00)00008-8. (76) Kaye, J. P.; Hart, S. C., Competition for nitrogen between plants and soil microorganisms. Trends Ecol. Evol. 1997, 12 (4), 139-143; DOI: 10.1016/s0169-5347(97)01001-x.
25 ACS Paragon Plus Environment
Environmental Science & Technology
583 584 585 586
(77) Paungfoo-Lonhienne, C.; Lonhienne, T. G. A.; Rentsch, D.; Robinson, N.; Christie, M.; Webb, R. I.; Gamage, H. K.; Carroll, B. J.; Schenk, P. M.; Schmidt, S., Plants can use protein as a nitrogen source without assistance from other organisms. PNAS 2008, 105 (11), 4524-4529; DOI: 10.1073/pnas.0712078105.
587
26 ACS Paragon Plus Environment
Page 26 of 33
Page 27 of 33
Environmental Science & Technology
588
Figures and Tables
589
Tables:
590
Table 1. Seasonal mass concentrations of proteins and FAAs in PM2.5 at Tianhu.
591
Table 2. Mass concentrations of proteins and total FAAs in comparison to other studies
592
(range, arithmetic mean and standard deviation).
593
Figures:
594
Figure 1. Average percentage distributions of individual AAs in PM2.5. The category of
595
“other” includes Asn (2.2 %), Gln (2.2 %), Asp (1.9 %), Tyr (1.5 %), and His (0.3 %)
596
(calculated by molar concentration).
597
Figure 2. Temporal variations of proteinaceous matter in PM2.5 and other data measured
598
at Tianhu: (a) proteins and total FAAs; (b) PM2.5 and O3; (c) OC and EC; (d) major ions
599
(Na+, NH4+, K+, Cl-, NO3-, and SO42-); (e) precipitation (the precipitation data were
600
obtained from http://www.wunderground.com/, and the shadow area is the rainy period).
601
Figure 3. Correlations between proteinaceous matter in PM2.5 and ambient O3: (a)
602
proteins vs. O3; (b) total FAAs vs. O3; (c) total FAAs vs. [O3][Proteins]; (d) Gly vs.
603
[O3][Proteins].
27 ACS Paragon Plus Environment
Environmental Science & Technology
Table 1. Seasonal mass concentrations of proteins and FAAs in PM2.5 at Tianhu.
604 605
606
Page 28 of 33
Compounds
Annual
Spring a
Summer a
Autumn a
Winter a
Proteins (µg m-3) FAAs (×10-3 µg m-3) Aspartic acid (Asp) Glutamic acid (Glu) Asparagine (Asn) Serine (Ser) Glutamine (Gln) Histidine (His) Glycine (Gly) Threonine (Thr) Arginine (Arg) Alanine (Ala) Tyrosine (Tyr) Valine (Val) Methionine (Met) Phenylalanine (Phe) Lysine (Lys) Total FAAs Proteins/PM2.5 (%) Total FAAs/PM2.5 (%)
0.79 ± 0.47
0.55 ± 0.43
0.61 ± 0.36
1.05 ± 0.45
0.93 ± 0.48
2.47 ± 0.80 3.37 ± 0.90 2.91 ± 0.67 4.68 ± 1.49 2.87 ± 0.75 0.43 ± 0.19 26.39 ± 14.89 5.31 ± 4.12 3.44 ± 2.33 4.60 ± 2.84 2.04 ± 0.68 24.55 ± 13.68 21.44 ± 9.44 17.96 ± 6.58 10.45 ± 6.35 132.91 ± 48.38 1.94 ± 0.73 0.34 ± 0.10
2.69 ± 0.85 3.31 ± 0.40 2.94 ± 0.21 5.13 ± 2.06 2.96 ± 0.26 0.51 ± 0.12 17.85 ± 9.60 2.95 ± 1.48 2.54 ± 0.72 2.78 ± 1.04 1.75 ± 0.19 16.06 ± 5.36 20.86 ± 8.73 15.51 ± 2.33 9.36 ± 4.59 107.20 ± 25.66 1.68 ± 0.74 0.39 ± 0.08
2.38 ± 0.72 3.46 ± 1.23 2.96 ± 1.15 4.68 ± 1.28 3.06 ± 1.32 0.45 ± 0.24 21.62 ± 7.89 4.51 ± 1.68 2.50 ± 0.61 3.59 ± 1.08 1.99 ± 0.69 17.65 ± 10.73 21.30 ± 11.09 14.64 ± 4.54 10.25 ± 5.29 115.04 ± 34.76 1.77 ± 0.95 0.32 ± 0.11
3.04 ± 0.89 3.80 ± 0.71 2.95 ± 0.47 5.11 ± 1.52 2.93 ± 0.52 0.48 ± 0.24 42.06 ± 18.14 6.88 ± 2.84 6.40 ± 3.09 6.86 ± 3.53 2.52 ± 0.86 40.75 ± 13.70 26.55 ± 9.95 22.29 ± 5.95 13.06 ± 4.46 185.70 ± 55.65 1.89 ± 0.41 0.33 ± 0.07
1.92 ± 0.25 2.97 ± 0.85 2.82 ± 0.44 3.97 ± 0.94 2.59 ± 0.24 0.30 ± 0.05 23.13 ± 10.25 6.39 ± 6.57 2.42 ± 0.75 4.90 ± 3.01 1.87 ± 0.53 23.13 ± 7.65 17.59 ± 6.24 19.09 ± 8.52 9.16 ± 9.09 122.63 ± 30.57 2.33 ± 0.59 0.32 ± 0.10
a
the sampling period was classified into four seasons: spring (Mar.-May), summer (Jun.-Aug.), autumn (Sep.- Nov.), and winter (Dec.-Feb.).
28 ACS Paragon Plus Environment
Page 29 of 33
607 608 609
Environmental Science & Technology
Table 2. Mass concentrations of proteins and total FAAs in comparison to other studies (range, arithmetic mean and standard deviation). Sampling site
Type of aerosol
Sampling time
PM size
Concentrations Range
Reference Mean± SD
a
-3
Proteins (µg m ) Guangzhou, China
rural
March 2012-February 2013
PM2.5
0.20-1.86
0.79±0.47
this study
North Carolina (Orange County), US
rural
March-May 2007
PM2.5
< MDL -0.14
0.09
18
California (outside of home), US
suburban
October 2005-May 2006
PM2.5
0.07-7.20
0.60
16
North Carolina (Chapel Hill), US
suburban
August 2003-January 2004
PM2.5
< MDL-0.20
0.11
17
Arizona (Phoenix), US
suburban
2002-2003 (winter, spring and summer)
PM2.5
0.40-3.30
PM2.5
0.30-1.00
PM10
< MDL-4.98
1.96
PM10
0.42-4.91
1.51
rural Iowa, US
urban
2012 (January, April, July and October)
rural
b
20
19
Hefei, China
urban
June 2008-February 2009
PM10
2.08-36.7
11.4
14
California (outside of home), US
suburban
October 2005-May 2006
PM10
0.08-8.30
0.90
16
North Carolina (Orange County), US
rural
March-May 2007
PM10
< MDL-0.43
0.27
18
Mexico City, Mexico
urban/suburban
July-December 2000
PM10
0.04-0.17
13
Ecuador, South America
rural
2009 (several months)
TSP
0.07-0.32
15
Crete island (Finokalia), Greece
marine
June-August 2007
TSP
0.05-1.21
0.42
34
California (outside of home), US
suburban
October 2005-May 2006
TSP
0.20-9.30
1.40
16
rural
March 2012-February 2013
PM2.5
59.2-279
133 ± 48.4
Total FAAs (×10-3 µg m-3) Guangzhou, China Xi’an, China
urban
July 2008-August 2009
610
29 ACS Paragon Plus Environment
PM2.5
44.1-592
c
181
c
this study 21
Environmental Science & Technology
611 612
Page 30 of 33
Table 2. Continued. Sampling site
Type of aerosol
Sampling time
PM size
Concentrations Range
-3
Mean± SD
Reference a
-3
Total FAAs (×10 µg m ) Roma, Italy
urban
2013 (winter)
PM2.5
167
2013 (summer)
PM2.5
193
23
North Carolina (Research Triangle Park), US
suburban
September-October 2010
PM2.5
2.00-31.0
11.0
22
North Carolina (Duke University forest), US
rural
July-August 2010
PM2.5
11.0-40.0
22.0
45
Nanjing (Nanjing University), China
urban suburban rural rural
PM2.5 PM2.5 PM2.5 PM2.5 PM2.5
81.9-188 39.3-162 58.5-396
129 84.9 189 25.7 56.8
24
Nanjing (Purple Mountain), China Jeju Island (Gusan), Korea California (Davis), US
February 2001 September 2001 February 2001 March-April 2001 August 1997-July 1998
Hong Kong, China
urban
November 2000-October 2001
PM2.5
83.9-192
Roma, Italy
urban
2013 (winter)
PM10
2013 (summer)
PM10
Rondonia (Amazon Basin), Brazil MZ Station, Antarctica
rural polar
7.83-325
27, 46 25
195
23
272 d
20.6 d
1999 (wet seasons)
PM10
0.76-166
1999 (dry seasons)
PM10
0.69-42.1 d
2010-2013
PM10
1.51 c
PM10
0.10 c
Dome C Station, Antarctica
30
26
10.8 d 35
Svalbard Islands, Norway
polar
April-September 2010
PM10
0.08-0.65 c
Southern Ocean (cruise)
polar
2010-2013
TSP
0.27-1.64 c
0.48 c
35
Crete island (Finokalia), Greece
marine
June-August 2007
TSP
0.82-88.8 c
23.6 c
34
613 614 30 ACS Paragon Plus Environment
36
Page 31 of 33
615 616
Environmental Science & Technology
Table 2. Continued. Sampling site
Type of aerosol
Sampling time
PM size
Concentrations Range
-3
Mean± SD
Reference a
-3
Total FAAs (×10 µg m ) Qingdao (coastal), China
617 618 619 620 621 622
marine
March-April 2006
TSP
214
South China Sea (cruise)
April-May 2005
TSP
31.0-58.2
Yellow Sea (cruise)
March 2005, April 2006
TSP
27.5-238
29
44.5 131 c
2.74 c
11
Atlantic Ocean (cruise)
marine
May-June 2003
TSP
0.41-13.7
North Pacific Ocean (cruise)
marine
May-July 2000
TSP
0.15-3.01 d
1.05 d
33
Tasmania (Cape Grim), Australia
marine
November-December 2000
TSP
1.96-21.5 d
9.79 d
31
Erdemli (Mediterranean coast), Turkey
marine
March-May 2000
TSP
3.91-110 d
36.2 d
32
a
standard deviation; below the method detection limit (< MDL); c concentrations converted from pmol m-3 to ng m-3 assuming an average molecular weight of 137 for AAs; d concentrations converted from nmol m-3 of nitrogen to ng m-3 of AAs assuming 1.4 nitrogen atoms per AA molecule and an average molecular weight of 137 for AAs. b
31 ACS Paragon Plus Environment
Environmental Science & Technology
623 624 625 626
Figure 1. Average percentage distributions of individual AAs in PM2.5. The category of “other” includes Asn (2.2 %), Gln (2.2 %), Asp (1.9 %), Tyr (1.5 %), and His (0.3 %) (calculated by molar concentration).
627
628 629 630 631 632
Figure 2. Temporal variations of proteinaceous matter in PM2.5 and other data measured at Tianhu: (a) proteins and total FAAs; (b) PM2.5 and O3; (c) OC and EC; (d) major ions (Na+, NH4+, K+, Cl-, NO3-, and SO42-); (e) precipitation (the precipitation data were obtained from http://www.wunderground.com/, and the shadow area is the rainy period).
32 ACS Paragon Plus Environment
Page 32 of 33
Page 33 of 33
Environmental Science & Technology
633
634 635 636 637
Figure 3. Correlations between proteinaceous matter in PM2.5 and ambient O3: (a) proteins vs. O3; (b) total FAAs vs. O3; (c) total FAAs vs. [O3][Proteins]; (d) Gly vs. [O3][Proteins].
33 ACS Paragon Plus Environment
