title: Anaerobic induction of Escherichia coli formate dehydrogenase (hydrogenase-linked) is enhanced by gyrase inactivation.
abstract: Escherichia coli synthesizes a hydrogenase-linked formate dehydrogenase (FDHH) under anaerobic conditions in the absence of nitrate. In striking contrast to many other anaerobic-specific genes, which require DNA to be negatively supercoiled for expression, we have found that inhibition of DNA gyrase activity enhances expression from the gene (fdhF) encoding the selenopolypeptide of FDHH. Fusions of the 5' flanking region of fdhF and the structural gene of lacZ were used to determine fdhF expression under varying conditions. Chemical inhibitors and a temperature-sensitive mutant allowed in vivo inhibition of gyrase activity. In each case, concomitant with gyrase inhibition there was a substantial increase in the induction of fusion protein synthesis. This enhancement of expression is observed for the intact fdhF gene residing on the chromosome as well as the fusion gene in a multicopy plasmid. Inhibition of gyrase activity will partially overcome the inhibition of fdhF expression due to nitrate but does not allow fusion protein synthesis in the presence of oxygen.
authors.affiliation: Laboratory of Biochemistry, National Heart, Lung, and Blood Institute, Bethesda, MD 20892.
authors.forename: M J
authors.initials: MJ
authors.lastname: Axley
authors.forename: T C
authors.initials: TC
authors.lastname: Stadtman
mesh_terms: D000445:Aldehyde Oxidoreductases / Q000096:biosynthesis*; D049933:Aminocoumarins; D000693:Anaerobiosis; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D003374:Coumarins / Q000494:pharmacology; D003545:Cysteine / Q000031:analogs & derivatives / Q000378:metabolism; D004250:DNA Topoisomerases, Type II / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004278:DNA, Superhelical / Q000235:genetics; D004790:Enzyme Induction / Q000187:drug effects; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D005560:Formate Dehydrogenases / Q000096:biosynthesis*; D009268:Nalidixic Acid / Q000494:pharmacology; D009566:Nitrates / Q000494:pharmacology; D009675:Novobiocin / Q000494:pharmacology; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D012643:Selenium / Q000378:metabolism; D017279:Selenocysteine; D059005:Topoisomerase II Inhibitors
chemical_list: D049933:Aminocoumarins; D001426:Bacterial Proteins; D003374:Coumarins; D004269:DNA, Bacterial; D004278:DNA, Superhelical; D009566:Nitrates; D011993:Recombinant Fusion Proteins; D059005:Topoisomerase II Inhibitors; D017279:Selenocysteine; D009675:Novobiocin; D009268:Nalidixic Acid; D005560:Formate Dehydrogenases; D000445:Aldehyde Oxidoreductases; C020644:Formate dehydrogenase (cytochrome); D004250:DNA Topoisomerases, Type II; D012643:Selenium; D003545:Cysteine; C004628:coumermycin