Protein Family Models

This family represents a unit of six transmembrane helices. Many members of the ABC transporter family (Pfam:PF00005) have two such regions. (from Pfam)

Date:

2024-08-14

ABC transporters for a large family of proteins responsible for translocation of a variety of compounds across biological membranes. ABC transporters are the largest family of proteins in many completely sequenced bacteria. ABC transporters are composed of two copies of this domain and two copies of a transmembrane domain Pfam:PF00664. These four domains may belong to a single polypeptide as in Swiss:P13569, or belong in different polypeptide chains. [1]. 1864505. Homology between proteins controlling Streptomyces fradiae. tylosin resistance and ATP-binding transport.. Rosteck PR Jr, Reynolds PA, Hershberger CL;. Gene 1991;102:27-32.. [2]. 1977073. Structure and function of haemolysin B,P-glycoprotein and other. members of a novel family of membrane translocators.. Blight MA, Holland IB;. Mol Microbiol 1990;4:873-880.. [3]. 2229036. Binding protein-dependent transport systems.. Higgins CF, Hyde SC, Mimmack MM, Gileadi U, Gill DR, Gallagher. MP;. J Bioenerg Biomembr 1990;22:571-592.. [4]. 9872322. Crystal structure of the ATP-binding subunit of an ABC. transporter.. Hung LW, Wang IX, Nikaido K, Liu PQ, Ames GF, Kim SH;. Nature 1998;396:703-707. (from Pfam)

Date:

2024-08-14

The gene pair cydCD encodes an ABC-family transporter in which each gene contains an N-terminal membrane-spanning domain (PF00664) and a C-terminal ATP-binding domain (PF00005). In E. coli these genes were discovered as mutants which caused the terminal heme-copper oxidase complex cytochrome bd to fail to assemble. Recent work has shown that the transporter is involved in export of redox-active thiol compounds such as cysteine and glutathione [1,2]. The linkage to assembly of the cytochrome bd complex is further supported by the conserved operon structure found outside the gammaproteobacteria (cydABCD) containing both the transporter and oxidase genes components. The genes used as the seed members for this model are all either found in the gammproteobacterial context or the CydABCD context. All members of this family scoring above trusted at the time of its creation were from genomes which encode a cytochrome bd complex. Unfortunately, the gene symbol nomenclature adopted based on this operon in B. subtilis assigns cydC to the third gene in the operon where this gene is actually homologous to the E. coli cydD gene. We have chosen to name all homologs in this family in accordance with the precedence of publication of the E. coli name, CydD. Recently, it has been shown that CydDC also function as a cytoplasmic cystine reductase (PMID: 32900959).

Gene:

cydD

Date:

2024-06-14