Type: | Family | Name: | Peptidase C10, streptopain |
Description: | Cysteine peptidases have characteristic molecular topologies, which can be seen not only in their three-dimensional structures, but commonly also in the two-dimensional structures. These are peptidases in which the nucleophile is the sulphydryl group of a cysteine residue. Cysteine proteases are divided into clans (proteins which are evolutionary related), and further sub-divided into families, on the basis of the architecture of their catalytic dyad or triad []. This group of cysteine peptidases belong to MEROPS peptidase family C10 (streptopain family, clan CA). Streptopain is a cysteine protease found in Streptococcus pyogenesthat shows some structural and functional similarity to papain (family C1) [, ]. The order of the catalytic cysteine/histidine dyad is the same and the surrounding sequences are similar. The two proteins also show similar specificities, both preferring a hydrophobic residue at the P2 site [, ].Streptopain shows a high degree of sequence similarity to the S. pyogenes exotoxin B, and strong similarity to the prtT gene product of Porphyromonas gingivalis(Bacteroides gingivalis), both of which have been included in the family []. | Short Name: | Peptidase_C10 |