Nitrogen dioxide reaction with proteins: Evidence for peptide bond cleavage at lysine residues

Miscellaneous · Tue Jan 01 00:00:00 EST 1991

OSTI ID:5086046

Hood, D B

Nitrogen dioxide (NO{sub 2}), an air pollutant produced by burning fossil fuels and a component of cigarette smoke, is thought to contribute to the pathogenesis of pulmonary diseases, such as emphysema. To gain information on the mechanism by which NO{sub 2} damages the lung, in vitro exposures of {alpha}{sub 1}-proteinase inhibitor ({alpha}{sub 1}-PI), elastin, bovine serum albumin (BSA), human serum albumin (HSA) and synthetic poly-L-lysine were performed. A genetic deficiency of {alpha}{sup 1}-PI predisposes humans to emphysema and NO{sub 2} has been hypothesized to damage {alpha}{sub 1}-PI, which would leave proteases such as human neutrophil elastase, (HNE) free to attack lung structural proteins. The ability of {alpha}{sub 1}-PI to inhibit HNE declined with exposure to 50% of the control value at molar ratios of NO{sub 2}:{alpha}{sub 1}-PI of 400:1 and greater. Exposure of {alpha}{sub 1}-PI to NO{sub 2} resulted in a 50% lose of immunoreactivity with either monoclonal or polyclonal antibodies in an enzyme-linked immunosorbent assay at molar ratios of NO{sub 2}:{alpha}{sub 1}-PI of essentially 100:1 and greater. The mechanisms of these effects were investigated via ultraviolet-visible spectroscopy and amino acid analysis. The remaining target molecules were labeled by reductive methylation of amino groups with {sup 3}H-HCHO prior to treatment with NO{sub 2} in aqueous solutions at physiological pH. Time course exposure of 5 mg {sup 3}H-insoluble bovine ligamentum nuchae elastin suspensions with up to 120 {mu}moles of NO{sub 2} resulted in 90% solubilization of the label. Amino acid analysis of the soluble and insoluble fractions from these exposures confirmed that 80% of the {sup 3}H-dimethyllysine residues were in the soluble fraction.

• Research Organization: East Tennessee State Univ., Johnson City, TN (United States)
• OSTI ID: 5086046
• Resource Relation: Other Information: Thesis (Ph.D.)
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
NITROGEN DIOXIDE
HEALTH HAZARDS
RESPIRATORY SYSTEM DISEASES
PATHOGENESIS
AIR POLLUTION
AMINO ACID SEQUENCE
ENZYME IMMUNOASSAY
ENZYME INHIBITORS
LYSINE
MAN
METABOLISM
PEPTIDE HYDROLASES
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ULTRAVIOLET SPECTRA
AMINO ACIDS
ANIMALS
BIOASSAY
CARBOXYLIC ACIDS
CHALCOGENIDES
DISEASES
ENZYMES
HAZARDS
HYDROGEN COMPOUNDS
HYDROLASES
IMMUNOASSAY
ISOTOPE APPLICATIONS
MAMMALS
MOLECULAR STRUCTURE
NITROGEN COMPOUNDS
NITROGEN OXIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLLUTION
PRIMATES
PROTEINS
SPECTRA
VERTEBRATES
560300* - Chemicals Metabolism & Toxicology