Protein Family Models

This entry includes decaheme cytochrome c component MtrC from the MtrCAB complex and its homologues MtrF (which is part of the MtrFDE complex) and OmcA. In Shewanella oneidensis, these proteins are located at the bacterial cell surface at the termini of trans-outer-membrane electron transfer conduits and allow the utilization of extracellular mineral forms of iron and manganese as respiratory electron acceptors [5,6]. MtrC/MtrF/OmcA consist of four domains: domain I and III containing seven antiparallel beta-strands in an extended Greek key topology; domains II and IV each bind five tightly packed hemes covalently attached to the Cys residues of the five CXXCH motifs in each domain and form the central core, flanked by domains I (Pfam:PF22111) and III [5,6]. This entry represents domains II and IV. Paper describing PDB structure 19hc. [1]. 10368280. The primary and three-dimensional structures of a nine-haem cytochrome c from Desulfovibrio desulfuricans ATCC 27774 reveal a new member of the Hmc family. Matias PM, Coelho R, Pereira IA, Coelho AV, Thompson AW, Sieker LC, Gall JL, Carrondo MA;. Structure. 1999;7:119-130. Paper describing PDB structure 1duw. [2]. 11170457. Three-dimensional structure of the nonaheme cytochrome c from Desulfovibrio desulfuricans Essex in the Fe(III) state at 1.89 A resolution. Umhau S, Fritz G, Diederichs K, Breed J, Welte W, Kroneck PM;. Biochemistry. 2001;40:1308-1316. Paper describing PDB structure 1dxr. [3]. 11005826. Structural basis of the drastically increased initial electron transfer rate in the reaction center from a Rhodopseudomonas viridis mutant described at 2.00-A resolution. Lanc. TRUNCATED at 1650 bytes (from Pfam)

Date:

2024-10-28

Within the NapC/NirT family of cytochrome c proteins, some members, such as NapC Swiss:P33932 and NirT Swiss:P24038, bind four haem groups, while others, such as TorC Swiss:P33226, bind five haems. This family aligns the common N-terminal region that contains four haem-binding C-X(2)-CH motifs. [1]. 11056172. Electron transfer and binding of the c-type cytochrome TorC to the trimethylamine N-oxide reductase in Escherichia coli. Gon S, Giudici-Orticoni MT, Mejean V, Iobbi-Nivol C;. J Biol Chem 2001;276:11545-11551. [2]. 7639719. The napEDABC gene cluster encoding the periplasmic nitrate reductase system of Thiosphaera pantotropha. Berks BC, Richardson DJ, Reilly A, Willis AC, Ferguson SJ;. Biochem J 1995;309:983-992. [3]. 8022286. TMAO anaerobic respiration in Escherichia coli: involvement of the tor operon. Mejean V, Iobbi-Nivol C, Lepelletier M, Giordano G, Chippaux M, Pascal MC;. Mol Microbiol 1994;11:1169-1179. (from Pfam)

Date:

2024-10-16

Nearly every member of this subfamily is NapC, a predicted membrane-anchored four-heme c-type cytochrome that forms one component of the periplasmic nitrate reductase along with NapA, NapB, NapD, NapE, and NapF subunits. A single known exception at this time is NirT, which is instead a component of a nitrite reductase. This family excludes TorC subunits of trimethylamine N-oxide (TMAO) reductases.

Date:

2024-05-30