Summary for clan SC

Summary Alignment Structure Literature
Clan type peptidaseS10.005 - serine carboxypeptidase D (Triticum aestivum), MEROPS Accession MER0000416 (peptidase unit: 15-437); PDB accession 1BCS
HistoryMethods Enzymol. 244:461-486 (1994)
DescriptionSerine nucleophile; catalytic residues in the order Ser, Asp, His in sequence
Contents of clanClan SC includes both endopeptidases and exopeptidases.
Evidence(See Protein fold.)
Catalytic mechanismThe active site residues are in the order Ser, Asp, His in the sequence (see the Alignment).
Peptidase activityThe endopeptidases include oligopeptidases, and the exopeptidases include aminopeptidases and carboxypeptidases. Specificities are very varied (see individual family summaries).
Protein foldTertiary structures have been determined for members of several families, the first being that of wheat serine carboxypeptidase II (S10.005; Liao & Remington, 1990). Peptidases in clan SC are proteins with a core consisting of an alpha/beta/alpha sandwich, in which the beta sheet has eight strands (in the order 12435678 in which strand 2 is antiparallel to the rest).
Homologous non-peptidase familiesThe fold for members of clan SC is shared with many other enzymes, and has been called the 'alpha-beta hydrolase' fold. Other enzymes with this fold include acetylcholinesterase, haloalkane dehalogenase, dienelactone hydrolase, bromoperoxidase A2, thioesterase, triacylglycerol lipase, hydroxynitrile lyase and a variety of other esterases and lipases. Not all of these enzymes are hydrolases (for example haloalkane dehalogenase) and not all of these enzymes have Ser as the nucleophile (for example dienelactone hydrolase has Cys and haloalkane dehalogenase has Asp) (Ollis et al., 1992; Cygler et al., 1993).
Activation mechanism(See family summaries.)
Other databases PFAMCL0028
SCOP53474

Families

Family Family Type Peptidase Structure
S9 prolyl oligopeptidase (Sus scrofa) Yes
S10 carboxypeptidase Y (Saccharomyces cerevisiae) Yes
S15 Xaa-Pro dipeptidyl-peptidase (Lactococcus lactis) Yes
S28 lysosomal Pro-Xaa carboxypeptidase (Homo sapiens) Yes
S33 prolyl aminopeptidase (Neisseria gonorrhoeae) Yes
S37 PS-10 peptidase (Streptomyces lividans) -

Distribution of clan SC among Kingdoms of Organisms

FamilyBacteriaArchaeaProtozoaFungiPlantsAnimalsViruses
S9+++++++
S10++++++-
S15++++++-
S28+-+++++
S33+++++++
S37+------
Clan+++++++