Influence of cytochrome c‐deficiency on the energy conservation of whole cells of Acetobacter methanolicus sp. MB 58

Abstract

AbstractThe ability of A. methanolicus sp. MB 58 and of a cytochrome c‐deficient mutant (A. methanolicus sp. MB 58105) to synthesize ATP by the oxidation of methanol, ethanol, glucose, formate and formaldehyde was investigated. It was found out that cells of the wild type were energized and that cells of the mutant were not energized by the oxidation of ethanol.The energization of cells by the oxidation of glucose, formate and formaldehyde is obviously not influenced by the cytochrome c defect. The results point to a coupling of the alcohol dehydrogenase at cytochrome c, as already postulated in a previous paper for the alcohol and the methanol dehydrogenases of A. methanolicus sp. MB 70.The dehydrogenases responsible for the oxidation of glucose and formate should be coupled to other cytochromes of the respiratory chain. Evidence for the coupling of the formaldehyde dehydrogenase could not be obtained, because it was not possible to differentiate between cytochrome‐dependent oxidation of formaldehyde and the NAD+‐dependent oxidations after fixation of formaldehyde.