title: Characterization of Escherichia coli [NiFe]-hydrogenase distribution during fermentative growth at different pHs.
abstract: The contribution made by each of the three active [NiFe]-hydrogenases (Hyd) of Escherichia coli during fermentation of glucose or glycerol in peptone-based medium at different pHs was analysed. The activities of the hydrogen-oxidizing Hyd-1 and Hyd-2 enzymes showed a reciprocal dependence on the pH of the medium while Hyd-3, a key component of the hydrogen-evolving formate hydrogenlyase complex, was mainly active at pH 6.5. Our findings identify the conditions during fermentation of glucose or glycerol under which each [NiFe]-hydrogenase is optimally active and demonstrate a previously unrecognized dependence on Hyd-1 activity at low pH.
authors.affiliation: Department of Biophysics, Yerevan State University, 1 A. Manoukian Str., 0025 Yerevan, Armenia.
authors.forename: Karen
authors.initials: K
authors.lastname: Trchounian
authors.forename: Constanze
authors.initials: C
authors.lastname: Pinske
authors.forename: R Gary
authors.initials: RG
authors.lastname: Sawers
authors.forename: Armen
authors.initials: A
authors.lastname: Trchounian
mesh_terms: D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology*; D005285:Fermentation; D005947:Glucose / Q000494:pharmacology; D005990:Glycerol / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D006864:Hydrogenase / Q000378:metabolism*; D010088:Oxidoreductases / Q000378:metabolism; D020033:Protein Isoforms / Q000378:metabolism
chemical_list: D020033:Protein Isoforms; D010088:Oxidoreductases; C043296:nickel-iron hydrogenase; C029746:uptake hydrogenase; D006864:Hydrogenase; D005947:Glucose; D005990:Glycerol