Open AccessLithoautotrophic growth of the freshwater strain Beggiatoa D‐402 and energy conservation in a homogeneous culture under microoxic conditions
Author(s) -
Grabovich Margarita Yu,
Patritskaya Valentina Yu,
Muntyan Maria S,
Dubinina Galina A
Publication year - 2001
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.1574-6968.2001.tb10908.x
Subject(s) - thiosulfate , biochemistry , oxidative phosphorylation , sulfur , enzyme , chemistry , carbon fixation , bacteria , cytochrome , cytochrome c oxidase , sodium thiosulfate , yield (engineering) , strain (injury) , respiratory chain , biology , photosynthesis , organic chemistry , materials science , anatomy , metallurgy , genetics
The freshwater filamentous bacterium Beggiatoa D‐402 was shown to grow lithoautotrophically in a homogeneous culture under microoxic conditions only, the growth yield being the highest at 0.1 mg O 2 l −1 . High activities of the Calvin cycle key enzymes and of the dissimilatory path thiosulfate oxidation enzymes were found in the bacterial cells. The rate of CO 2 fixation above 112 nmol min −1 (mg protein) −1 , an about 90% increase in the protein carbon at the expense of CO 2 carbon and an increase in the molar yield up to 12 mg dry weight (mmol oxidized thiosulfate) −1 indicate the bacterial growth was autotrophic. Thiosulfate was oxidized by the strain almost completely into sulfate. The metabolically useful energy was conserved by oxidative phosphorylation that was coupled to oxidation of sulfur compounds. The bacterial membranes were found to contain CO‐binding cytochromes b and two cytochromes c with M r 23 and 26 kDa, the terminal part of the respiratory chain containing presumably a cbb 3 ‐type oxidase. A cytochrome c with M r 12 kDa was detected in the soluble fraction.