Corynebacterium glutamicum is the major host for the industrial production of amino acids and has become one of the best studied model organisms in microbial biotechnology. Rational strain construction has led to an improvement of producer strains and to a variety of novel producer strains with a broad substrate and product spectrum. A key factor for the success of these approaches is detailed knowledge of transcriptional regulation in C.
View Article and Find Full Text PDFThe influence of nitrate and nitrite on growth of Corynebacterium glutamicum under aerobic conditions in shake flasks was analysed. When dissolved oxygen became limiting at higher cell densities, nitrate was reduced almost stoichiometrically to nitrite by nitrate reductase (NarGHJI). The nitrite concentration also declined slowly, presumably as a result of several reactions including reduction to nitric oxide by a side-activity of nitrate reductase.
View Article and Find Full Text PDFIn this study a comparative analysis of three Corynebacterium glutamicum ATCC 13032 respiratory chain mutants lacking either the cytochrome bd branch (ΔcydAB), or the cytochrome bc1-aa3 branch (Δqcr), or both branches was performed. The lack of cytochrome bd oxidase was inhibitory only under conditions of oxygen limitation, whereas the absence of a functional cytochrome bc1-aa3 supercomplex led to decreases in growth rate, biomass yield, respiration and proton-motive force (pmf) and a strongly increased maintenance coefficient under oxygen excess. These results show that the bc1-aa3 supercomplex is of major importance for aerobic respiration.
View Article and Find Full Text PDF