LIS - Legume Information System
Information about legume traits for crop improvement
CicerMine
v5.1.0.3
Cicer data from the Legume Information System
v5.1.0.3
Cicer data from the Legume Information System
| Type | Domain |
| Description | This entry represents the C-terminal domain of Signal peptide peptidase A (SppA) from Escherichia coli and other members of the Peptidase S49 family (protease IV family, clan S in MEROPS) from cellular organisms.Signal peptide peptidase A is involved in the cleavage of signal peptides after their removal from the precursor proteins by signal peptidases. This entry includes S49 family members with either a single domain (sometimes referred to as 36K type), such as Escherichia coli SohB peptidase and archaeal sprotease MJ0651, or an N-terminal domain in addition to the C-terminal protease domain that is conserved in all the S49 family members (sometimes referred to as 67K type), similar to E. coli and Arabidopsis thaliana SppA peptidases [ , , ].Unlike the eukaryotic functional homologues that are proposed to be aspartic proteases, site-directed mutagenesis and sequence analysis have shown that members in this subfamily, mostly bacterial, are serine proteases. The predicted active site serine for members in this entry occurs in a transmembrane domain. Mutagenesis studies also suggest that the catalytic centre comprises a Ser-Lys dyad (both residues absolutely conserved within bacteria, chloroplast and mitochondrial signal peptidase family members) and not the usual Ser-His-Asp catalytic triad found in the majority of serine proteases. Interestingly, the single membrane spanning E. coli SppA carries out catalysis using a Ser-Lys dyad with the serine located in the C-terminal protease domain and the lysine in the N-terminal domain. The N- and C-terminal halves of SppA in E. coli are tandem repeats [ , , , ]. |
| Short Name | S49_SppA_C |
