Respiratory chain of bacterial membrane: assembly-mobile carriers equilibrium.

The target size of NADH-oxidase activity of M. lysodeikticus isolated membranes for electron radiation is nearly equal to that obtained for NADH-dehydrogenase (about 50 kD). The complete cross-linking of membrane proteins by glutaraldehyde causes an increase of NADH-oxidase target size to 3-3.5 times its original value. Electrons are transported by cross-linked respiratory chain from NADH to O2 with 60-50% effectiveness of that in untreated membranes. It is proposed that electrons are transported through a multi-enzymic complex of individual carriers having limited lifetime with exchange of carriers between different respiratory complexes via lateral diffusion in membrane.