Open AccessRegulation of carbon and electron flow in Propionispira arboris : physiological function of hydrogenase and its role in homopropionate formation
Author(s) -
Thompson T.E.,
Conrad R.,
Zeikus J.G.
Publication year - 1984
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1984.tb00739.x
Subject(s) - hydrogenase , propionate , fermentation , chemistry , hydrogen , hydrogen production , biochemistry , fumarate reductase , carbon fibers , enzyme , food science , organic chemistry , materials science , succinate dehydrogenase , composite number , composite material
Hydrogenase activity was characterized in cell extracts of Propionispira arboris that consumed or produced H 2 , coupled to methyl viologen reduction, and displayed highest levels (2.6 μmol/min/mg protein) in extracts prepared from fumarate‐grown cells. Reversible hydrogenase activity in cell extracts correlated with the production of low levels of hydrogen during the growth phase and its subsequent consumption during the stationary phase of cells grown on glucose or lactate as the carbon and energy source. The addition of exogenous hydrogen to glucose, lactate or fumarate‐grown cells dramatically increased propionate production at the expense of acetate formation. This accounted for the formation of propionate as nearly the sole end product of glucose fermentation under two atmospheres of hydrogen. The physiological function of hydrogenase in regulation of carbon and electron flow, and the significance of the results in applied and environmental microbiology are discussed.