Degradation of glyoxylate and glycolate with ATP synthesis by a thermophilic anaerobic bacterium, Moorella sp. strain HUC22-1.
The thermophilic homoacetogenic bacterium Moorella sp. strain HUC22-1 ferments glyoxylate to acetate roughly according to the reaction 2 glyoxylate --> acetate + 2 CO(2). A batch culture with glyoxylate and yeast extract yielded 11.7 g per mol of cells per substrate, which was much higher than that obtained with H(2) plus CO(2). Crude extracts of glyoxylate-grown cells catalyzed the ADP- and NADP-dependent condensation of glyoxylate and acetyl coenzyme A (acetyl-CoA) to pyruvate and CO(2) and converted pyruvate to acetyl-CoA and CO(2), which are the key reactions of the malyl-CoA pathway. ATP generation was also detected during the key enzyme reactions of this pathway. Furthermore, this bacterium consumed l-malate, an intermediate in the malyl-CoA pathway, and produced acetate. These findings suggest that Moorella sp. strain HUC22-1 can generate ATP by substrate-level phosphorylation during glyoxylate catabolism through the malyl-CoA pathway.
Sakai
Shinsuke
S
Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Kagamiyama 1-3-1, Higashi-Hiroshima 739-8530, Japan.
Inokuma
Kentaro
K
Nakashimada
Yutaka
Y
Nishio
Naomichi
N
D000214:Acyl Coenzyme A / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000096:biosynthesis*; D001421:Bacteria, Anaerobic / Q000254:growth & development / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D005285:Fermentation; D006016:Glycolates / Q000378:metabolism*; D006038:Glyoxylates / Q000378:metabolism*; D008293:Malates / Q000378:metabolism; D010766:Phosphorylation
D000214:Acyl Coenzyme A; D006016:Glycolates; D006038:Glyoxylates; D008293:Malates; C031149:glycolic acid; C042519:malyl-coenzyme A; C030298:malic acid; D000255:Adenosine Triphosphate; C031150:glyoxylic acid