Protein chaperones mediating copper insertion into the CuA site of the aa3-type cytochrome c oxidase of Paracoccus denitrificans.

The biogenesis of the mitochondrial cytochrome c oxidase is a complex process involving the stepwise assembly of its multiple subunits encoded by two genetic systems. Moreover, several chaperones are required to recruit and insert the redox-active metal centers into subunits I and II, two a-type hemes and a total of three copper ions, two of which form the CuA center located in a hydrophilic domain of subunit II. The copper-binding Sco protein(s) have been implicated with the metallation of this site in various model organisms.

Role of Surf1 in heme recruitment for bacterial COX biogenesis.

Biogenesis of the mitochondrial cytochrome c oxidase (COX) is a highly complex process involving subunits encoded both in the nuclear and the organellar genome; in addition, a large number of assembly factors participate in this process. The soil bacterium Paracoccus denitrificans is an interesting alternative model for the study of COX biogenesis events because the number of chaperones involved is restricted to an essential set acting in the metal centre formation of oxidase, and the high degree of sequence homology suggests the same basic mechanisms during early COX assembly. Over the last years, studies on the P.

Characterization of heme-binding properties of Paracoccus denitrificans Surf1 proteins.

Biogenesis of cytochrome c oxidase (COX) is a highly complex process involving >30 chaperones in eukaryotes; those required for the incorporation of the copper and heme cofactors are also conserved in bacteria. Surf1, associated with heme a insertion and with Leigh syndrome if defective in humans, is present as two homologs in the soil bacterium Paracoccus denitrificans, Surf1c and Surf1q. In an in vitro interaction assay, the heme a transfer from purified heme a synthase, CtaA, to Surf1c was followed, and both Surf proteins were tested for their heme a binding properties.

Surf1, associated with Leigh syndrome in humans, is a heme-binding protein in bacterial oxidase biogenesis.

Biogenesis of mitochondrial cytochrome c oxidase (COX) relies on a large number of assembly factors, among them the transmembrane protein Surf1. The loss of human Surf1 function is associated with Leigh syndrome, a fatal neurodegenerative disorder caused by severe COX deficiency. In the bacterium Paracoccus denitrificans, two homologous proteins, Surf1c and Surf1q, were identified, which we characterize in the present study.

Two variants of the assembly factor Surf1 target specific terminal oxidases in Paracoccus denitrificans.

Biogenesis of cytochrome c oxidase (COX) relies on a large number of assembly proteins, one of them being Surf1. In humans, the loss of Surf1 function is associated with Leigh syndrome, a fatal neurodegenerative disorder. In the soil bacterium Paracoccus denitrificans, homologous genes specifying Surf1 have been identified and located in two operons of terminal oxidases: surf1q is the last gene of the qox operon (coding for a ba(3)-type ubiquinol oxidase), and surf1c is found at the end of the cta operon (encoding subunits of the aa(3)-type cytochrome c oxidase).