An Escherichia coli mutant deficient in pyruvate oxidase activity due to altered phospholipid activation of the enzyme

Y Y Chang; J E Cronan

doi:10.1073/pnas.81.14.4348

An Escherichia coli mutant deficient in pyruvate oxidase activity due to altered phospholipid activation of the enzyme

Proc Natl Acad Sci U S A. 1984 Jul;81(14):4348-52. doi: 10.1073/pnas.81.14.4348.

Authors

Y Y Chang¹, J E Cronan

Affiliation

¹ Department of Microbiology, University of Illinois, 131 Burrill Hall, 407 South Goodwin, Urbana, IL 61801.

Abstract

The pyruvate oxidase (pyruvate:ferricytochrome b(1) oxidoreductase, EC 1.2.2.2) of Escherichia coli is markedly activated by phospholipids in vitro. To test the physiological relevance of this activation, we isolated an E. coli mutant producing an oxidase that is deficient in activation by (and binding to) phospholipids. The mutant oxidase could be fully activated by a specific proteolytic cleavage, indicating that the catalytic site is normal. The mutant enzyme functions poorly in vivo, indicating that activation of the oxidase by phospholipids plays an important physiological role.