>cd07023 S49_Sppa_N_C Signal peptide peptidase A (SppA), a serine protease, has catalytic Ser-Lys dyad. Signal peptide peptidase A (SppA; Peptidase S49; Protease IV): SppA is found in all three domains of life and is involved in the cleavage of signal peptides after their removal from the precursor proteins by signal peptidases. This subfamily contains members with either a single domain (sometimes referred to as 36K type), such as sohB peptidase, protein C and archaeal signal peptide peptidase, or an amino-terminal domain in addition to the carboxyl-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. Site-directed mutagenesis and sequence analysis have shown these SppAs to be serine proteases. The predicted active site serine for members in this family occurs in a transmembrane domain. Mutagenesis studies also suggest that the catalytic center comprises a Ser-Lys dyad

Probab=94.90  E-value=0.17  Score=29.62  Aligned_cols=24  Identities=25%  Similarity=0.353  Sum_probs=18.5

Q ss_pred             CCCHHHHHHHHHHHHHHHHHHHHC
Q ss_conf             988899885999999998999955
Q gi|254781049|r  178 ELQGQARIDGGDLFPNLYKAFCDK  201 (398)
Q Consensus       178 g~~~~~~~~~~~ii~~L~~~f~e~  201 (398)
T Consensus       139 ~~s~e~~~~~~~~ld~~~~~F~~~  162 (208)
T cd07023         139 PLTEEERAILQALVDDIYDQFVDV  162 (208)
T ss_pred             CCCHHHHHHHHHHHHHHHHHHHHH
T ss_conf             899999999999999999999999