$VAR1 = undef;

Summary for peptidase S77.001: prohead peptidase gp21 (bacteriophage T4)

Names
MEROPS Name	prohead peptidase gp21 (bacteriophage T4)
Other names	prohead proteinase (bacteriophage T4), proteinase P21

Domain architecture

MEROPS Classification
Classification	Clan SH >> Subclan (none) >> Family S77 >> Subfamily (none) >> S77.001
Holotype	prohead peptidase gp21 (bacteriophage T4) (Enterobacteria phage T4), Uniprot accession P06807 (peptidase unit: 1-212), MERNUM MER0001311
History	Identifier created: MEROPS 9.6 (29 February 2012)

Activity
Catalytic type	Serine
NC-IUBMB	Not yet included in IUBMB recommendations.
Cleavage site specificity	Explanations of how to interpret the following cleavage site sequence logo and specificity matrix can be found here.
Cleavage pattern	fkt/IL/at/Ea/-/-/- (based on 15 cleavages)

Specificity matrix

Amino acid	P4	P3	P2	P1	P1'	P2'	P3'	P4'
Gly	0	0	0	0	2	1	2	3
Pro	1	0	0	0	0	0	0	2
Ala	1	0	6	0	7	2	0	0
Val	0	0	1	0	0	0	2	1
Leu	1	6	1	0	2	1	1	1
Ile	0	7	1	0	1	0	3	0
Met	0	0	0	0	0	1	0	0
Phe	5	0	1	0	0	1	0	0
Tyr	0	0	0	0	0	0	0	0
Trp	0	0	0	0	0	0	0	0
Ser	0	0	1	0	0	1	1	0
Thr	3	0	4	0	0	1	0	1
Cys	0	0	0	0	0	0	1	0
Asn	0	1	0	0	1	0	0	0
Gln	0	0	0	0	1	1	0	0
Asp	0	0	0	0	0	0	1	2
Glu	1	1	0	15	0	4	3	2
Lys	3	0	0	0	1	0	1	3
Arg	0	0	0	0	0	1	0	0
His	0	0	0	0	0	1	0	0