Open AccessH+/e- stoichiometry for NADH dehydrogenase I and dimethyl sulfoxide reductase in anaerobically grown Escherichia coli cells
Author(s) -
Alexander V. Bogachev,
Rakhilya A. Murtazina,
Vladimir P. Skulachev
Publication year - 1996
Publication title -
journal of bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.652
H-Index - 246
eISSN - 1067-8832
pISSN - 0021-9193
DOI - 10.1128/jb.178.21.6233-6237.1996
Subject(s) - dimethyl sulfoxide , escherichia coli , stoichiometry , biology , reductase , biochemistry , dehydrogenase , enterobacteriaceae , mutant , enzyme , chemistry , organic chemistry , gene
Anaerobically grown Escherichia coli cells were shown to acidify the reaction medium in response to oxygen or dimethyl sulfoxide (DMSO) pulses, with the H+/e- stoichiometry being close to 2.5 and 1.5, respectively. In the presence of the NADH dehydrogenase I (NDH-I) inhibitor 8-methyl-N-vanillyl-6-nonenamide (capsaicin) or in mutants lacking NDH-I, this ratio decreased to 1 for O2 and to 0 for DMSO. These data suggest that (i) the H+/e- stoichiometry for E. coli NDH-I is at least 1.5 and (ii) the DMSO reductase does not generate a proton motive force.