Deletion of genes encoding cytochrome oxidases and quinol monooxygenase blocks the aerobic-anaerobic shift in Escherichia coli K-12 MG1655.

ABSTRACT: The constitutive activation of the anoxic redox control transcriptional regulator (ArcA) in Escherichia coli during aerobic growth, with the consequent production of a strain that exhibits anaerobic physiology even in the presence of air, is reported in this work. Removal of three terminal cytochrome oxidase genes (cydAB, cyoABCD, and cbdAB) and a quinol monooxygenase gene (ygiN) from the E. coli K-12 MG1655 genome resulted in the activation of ArcA aerobically. These mutations resulted in reduction of the oxygen uptake rate by nearly 98% and production of d-lactate as a sole by-product under oxic and anoxic conditions. The knockout strain exhibited nearly identical physiological behaviors under both conditions, suggesting that the mutations resulted in significant metabolic and regulatory

SUBMITTER: Portnoy VA 

PROVIDER: S-EPMC2950451 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature