TY - JOUR
T1 - Light-induced protein nitration and degradation with HONO emission
AU - Meusel, Hannah
AU - Elshorbany, Yasin
AU - Kuhn, Uwe
AU - Bartels-Rausch, Thorsten
AU - Reinmuth, Kathrin
AU - Kampf, Christopher J
AU - Cheng, Yafang
N1 - Meusel, H., Elshorbany, Y., Kuhn, U., Bartels-Rausch, T., Reinmuth-Selzle, K., Kampf, C. J., … Cheng, Y. (2017). Light-induced protein nitration and degradation with HONO emission. Atmospheric Chemistry and Physics, 17(19), 11819–11833. https://doi.org/10.5194/acp-17-11819-2017
PY - 2017/1/1
Y1 - 2017/1/1
N2 - Proteins can be nitrated by air pollutants (NO2), enhancing their allergenic potential. This work provides insight into protein nitration and subsequent decomposition in the presence of solar radiation. We also investigated light-induced formation of nitrous acid (HONO) from protein surfaces that were nitrated either online with instantaneous gas-phase exposure to NO2 or offline by an efficient nitration agent (tetranitromethane, TNM). Bovine serum albumin (BSA) and ovalbumin (OVA) were used as model substances for proteins. Nitration degrees of about 1% were derived applying NO2 concentrations of 100 ppb under VIS=UV illuminated conditions, while simultaneous decomposition of (nitrated) proteins was also found during long-term (20 h) irradiation exposure. Measurements of gas exchange on TNM-nitrated proteins revealed that HONO can be formed and released even without contribution of instantaneous heterogeneous NO2 conversion. NO2 exposure was found to increase HONO emissions substantially. In particular, a strong dependence of HONO emissions on light intensity, relative humidity, NO2 concentrations and the applied coating thickness was found. The 20 h long-term studies revealed sustained HONO formation, even when concentrations of the intact (nitrated) proteins were too low to be detected after the gas exchange measurements. A reaction mechanism for the NO2 conversion based on the Langmuir–Hinshelwood kinetics is proposed.
AB - Proteins can be nitrated by air pollutants (NO2), enhancing their allergenic potential. This work provides insight into protein nitration and subsequent decomposition in the presence of solar radiation. We also investigated light-induced formation of nitrous acid (HONO) from protein surfaces that were nitrated either online with instantaneous gas-phase exposure to NO2 or offline by an efficient nitration agent (tetranitromethane, TNM). Bovine serum albumin (BSA) and ovalbumin (OVA) were used as model substances for proteins. Nitration degrees of about 1% were derived applying NO2 concentrations of 100 ppb under VIS=UV illuminated conditions, while simultaneous decomposition of (nitrated) proteins was also found during long-term (20 h) irradiation exposure. Measurements of gas exchange on TNM-nitrated proteins revealed that HONO can be formed and released even without contribution of instantaneous heterogeneous NO2 conversion. NO2 exposure was found to increase HONO emissions substantially. In particular, a strong dependence of HONO emissions on light intensity, relative humidity, NO2 concentrations and the applied coating thickness was found. The 20 h long-term studies revealed sustained HONO formation, even when concentrations of the intact (nitrated) proteins were too low to be detected after the gas exchange measurements. A reaction mechanism for the NO2 conversion based on the Langmuir–Hinshelwood kinetics is proposed.
KW - nitrous acid HONO, heterogeneous reaction, aerosol particles, quantum yields, photochemical production
KW - combustion conditions, photoenhanced uptake, laboratory systems, tyrosine oxidation
UR - https://digitalcommons.usf.edu/fac_publications/3651
M3 - Article
JO - Default journal
JF - Default journal
ER -