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Cardiolipin enhances the enzymatic activity of cytochrome bd and cytochrome bo₃ solubilized in dodecyl-maltoside.

ABSTRACT: Cardiolipin (CL) is a lipid that is found in the membranes of bacteria and the inner membranes of mitochondria. CL can increase the activity of integral membrane proteins, in particular components of respiratory pathways. We here report that CL activated detergent-solubilized cytochrome bd, a terminal oxidase from Escherichia coli. CL enhanced the oxygen consumption activity ~ twofold and decreased the apparent K_M value for ubiquinol-1 as substrate from 95 µM to 35 µM. Activation by CL was also observed for cytochrome bd from two Gram-positive species, Geobacillus thermodenitrificans and Corynebacterium glutamicum, and for cytochrome bo₃ from E. coli. Taken together, CL can enhance the activity of detergent-solubilized cytochrome bd and cytochrome bo₃.

SUBMITTER: Asseri AH

PROVIDER: S-EPMC8044227 | biostudies-literature |

REPOSITORIES: biostudies-literature

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In Escherichia coli Ammonia Inhibits Cytochrome bo3 But Activates Cytochrome bd-I.

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