VesB is a serine protease that is secreted by the type II secretion system (T2S) in Vibrio cholerae (Swiss:Q9KSQ6). It efficiently cleaves a trypsin substrate, but not chymotrypsin and elastase substrates [1]. It has been suggested to contribute to i ...
VesB is a serine protease that is secreted by the type II secretion system (T2S) in Vibrio cholerae (Swiss:Q9KSQ6). It efficiently cleaves a trypsin substrate, but not chymotrypsin and elastase substrates [1]. It has been suggested to contribute to intestinal growth or pathogenesis, although is not the only factor required for intestinal survival. VesB can cleave the A subunit of cholera toxin, a process important for cholera toxin activation [1]. It consists of a protease domain (Pfam:PF00089) followed by a Ig-like domain, represented in this entry, which may be involved in one or more different functions such as stabilizing the protease domain, co-defining substrate specificity, binding to the bacterial surface and being part of a yet undefined secretion motif of the T2S system [1]. This protein belongs to the chymotrypsin subfamily A (which includes mostly eukaryotic proteases), having a structure and specificity profile resembling that of eukaryotic trypsin-like proteases. This domain is also found in some eukaryotic proteins, such as HYDIN and CFA65 from human (which contain repeated Ig-like domains).
This domain is found at the C-terminal end of Swiss:Q7MX90 from Porphyromonas gingivalis (PG_0320) and similar bacterial sequences. This domain is usually found associated with Pfam:PF07610. It is functionally uncharacterised.
