A biochemical study of the reconstitution of d-lactate dehydrogenase-deficient membrane vesicles using fluorine-labeled components

Fluorine-19 labeled compounds have been incorporated into lipids and proteins of Escherichia coli. ¹⁹F-Labeled membrane vesicles, prepared by growing a fatty acid auxotroph of a d-lactate dehydrogenase-deficient strain on 8,8-difluoromyristic acid, can be reconstituted for oxidase and transport activities by binding exogenous d-lactate dehydrogenase. ¹⁹F-Labeled d-lactate dehydrogenases prepared by addition of fluorotryptophans to a tryptophan-requiring strain are able to reconstitute d-lactate dehydrogenase-deficient membrane vesicles. Thus, lipid and protein can be labeled independently and used to investigate protein-lipid interactions in membranes.