title: [Energy transformation coupled to formate oxidation during anaerobic fermentation].
abstract: A correlation between the rate of ATP synthesis by F0F1 ATP-synthase and formate oxidation by formate hydrogen lyase (FHL) has been established in inverted membrane vesicles of Escherichia coli JW 136 mutant with double deletions (delta hya/ delta hyb) of hydrogenase 1 and 2 grown anaerobically on glucose in the absence of external electron acceptors (pH 6.5). ATP synthesis was suppressed by H+ -ATPase inhibitors N,N'-dicyclohexylcarbodiimide (DCCD) and sodium azide as well as by the protonophore carbonyl cyanide-m-chlorophenyhydrazone (CCCP). Copper ions inhibited formate-dependent hydrogenase and ATP-synthase activities but did not affect the ATPase activity of vesicles. The maximal rate of ATP synthesis (0.83 microM/min x mg protein) stimulated by K+ ions was determined when sodium formate, ADP and inorganic phosphate were applied simultaneously. The results confirm the assumption about the dual role of hydrogenase 3, formate hydrogen lyase subunit, which is able to couple the reduction of protons to H2 and their translocation through a membrane with chemiosmotic synthesis of ATP.
authors.forename: M
authors.initials: M
authors.lastname: Akopian
authors.forename: A
authors.initials: A
authors.lastname: Poladian
authors.forename: K
authors.initials: K
authors.lastname: Bagramian
mesh_terms: D000244:Adenosine Diphosphate / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D000693:Anaerobiosis; D025243:Bacterial Proton-Translocating ATPases / Q000037:antagonists & inhibitors; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone / Q000494:pharmacology; D002738:Chloroquine / Q000031:analogs & derivatives / Q000494:pharmacology; D003300:Copper / Q000494:pharmacology; D004734:Energy Metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics; D005285:Fermentation; D005561:Formates / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D006864:Hydrogenase / Q000235:genetics; D007476:Ionophores / Q000494:pharmacology; D009154:Mutation; D010084:Oxidation-Reduction; D010710:Phosphates / Q000494:pharmacology; D019810:Sodium Azide / Q000494:pharmacology
chemical_list: D029968:Escherichia coli Proteins; D005561:Formates; D007476:Ionophores; D010710:Phosphates; C030544:formic acid; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone; D000244:Adenosine Diphosphate; D003300:Copper; D002738:Chloroquine; D000255:Adenosine Triphosphate; D019810:Sodium Azide; D006864:Hydrogenase; C481721:hydrogenase 2, E coli; D025243:Bacterial Proton-Translocating ATPases; D005947:Glucose; C033490:N,N-dideethylchloroquine; C029892:cupric chloride