Protein Family Models

Members of this family belong to the collagen superfamily [1]. Collagens are generally extracellular structural proteins involved in formation of connective tissue structure. The alignment contains 20 copies of the G-X-Y repeat that forms a triple helix. The first position of the repeat is glycine, the second and third positions can be any residue but are frequently proline and hydroxy-proline. Collagens are post translationally modified by proline hydroxylase to form the hydroxy-proline residues. Defective hydroxylation is the cause of scurvy. Some members of the collagen superfamily are not involved in connective tissue structure but share the same triple helical structure. The family includes bacterial collagen-like triple-helix repeat proteins [2,3]. [1]. 8240831. New members of the collagen superfamily. Mayne R, Brewton RG;. Curr Opin Cell Biol 1993;5:883-890. [2]. 11158359. Streptococcus pyogenes sclB encodes a putative hypervariable surface protein with a collagen-like repetitive structure. Whatmore AM;. Microbiology. 2001;147:419-429. [3]. 21726633. Characterisation of a large family of polymorphic collagen-like proteins in the endospore-forming bacterium Pasteuria ramosa. McElroy K, Mouton L, Du Pasquier L, Qi W, Ebert D;. Res Microbiol. 2011;162:701-714. (from Pfam)

Date:

2024-10-16

This domain occurs as the C-terminal region in a number of proteins that have extensive collagen-like triple helix repeat regions. Member domains are predicted by TmHMM to have four or five transmembrane helices. Members are found mostly in the Firmicutes, but also in Acanthamoeba polyphaga mimivirus. Members include spore surface glycoprotein BclB from Bacillus anthracis, a protein of the exosporium. The exosporium is an additional outermost spore layer, lacking in B. subtilis and most other spore formers, consisting of a basal layer and, above it, a nap of fine filaments.

Date:

2023-02-01

All protein sequence used in the seed alignment for this model comes from the N-terminal region of proteins with extended collagen-like Gly-rich repeat regions, and occur in Firmicutes.

Date:

2020-10-26