Quaternary structure of the oxaloacetate decarboxylase membrane complex and mechanistic relationships to pyruvate carboxylases.

ABSTRACT: The oxaloacetate decarboxylase primary Na(+) pump (OAD) is an essential membrane protein complex that functions in the citrate fermentation pathway of some pathogenic bacteria under anaerobic conditions. OAD contains three different subunits: Oad-α, a biotinylated extrinsic protein that catalyzes the α-ketodecarboxylation of oxaloacetate; Oad-γ, a structural bitopic membrane protein whose cytosolic tail (named as Oad-γ') binds tightly to Oad-α; and Oad-β, a multispan transmembrane α-helical protein that constitutes the Na(+) channel. How OAD is organized structurally at the membrane and what the molecular determinants are that lead to an efficient energy coupling mechanism remain elusive. In the present work, we elucidate the stoichiometry of the native complex as well as the low resolutio

SUBMITTER: Balsera M 

PROVIDER: S-EPMC3058996 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature