Oxygen-insensitive nitroreductases of Escherichia coli do not reduce 3-nitrotyrosine.

Article Details

Citation

Lightfoot RT, Shuman D, Ischiropoulos H

Oxygen-insensitive nitroreductases of Escherichia coli do not reduce 3-nitrotyrosine.

Free Radic Biol Med. 2000 Apr 1;28(7):1132-6.

PubMed ID
10832075 [ View in PubMed
]
Abstract

The oxygen-insensitive nitroreductases nfsA and nfsB are known to reduce para-nitrated aromatic compounds. We tested the hypothesis that these nitroreductases are capable of reducing 3-nitrotyrosine in proteins and peptides, as well as in free amino acids using wild-type and nfsA nfsB mutant strains of Escherichia coli. E. coli homogenates were incubated with nitrated proteins and the level of 3-nitrotyrosine immunoreactivity was assayed by Western blotting. Assay conditions that allow the nitroreductases to rapidly reduce nitrofurantoin did not result in the modification of 3-nitrotyrosine in protein, peptide, or free amino acid. Stimulation of nfsA nfsB activity with paraquat had no effect on 3-nitrotyrosine reduction. Nonlethal exposure of E. coli to peroxynitrite/CO(2) resulted in the reproducible nitration of tyrosine residues in endogenous proteins. The degree of 3-nitrotyrosine immunoreactivity over the 2-h postexposure period did not differ between mutant and wild-type strains. These results indicate that the nfsA and nfsB enzymes do not reduce 3-nitrotyrosine.

DrugBank Data that Cites this Article

Drug Targets
DrugTargetKindOrganismPharmacological ActionActions
NitrofurantoinOxygen-insensitive NADPH nitroreductaseProteinEscherichia coli (strain K12)
Yes
Potentiator
Details