Any feedback?
Please rate this page
(all_enzymes.php)
(0/150)

BRENDA support

3.4.23.1: pepsin A

This is an abbreviated version!
For detailed information about pepsin A, go to the full flat file.

Word Map on EC 3.4.23.1

Reaction

Preferential cleavage: hydrophobic, preferably aromatic, residues in P1 and P1' positions. Cleaves Phe1-/-Val, Gln4-/-His, Glu13-/-Ala, Ala14-/-Leu, Leu15-/-Tyr, Tyr16-/-Leu, Gly23-/-Phe, Phe24-/-Phe and Phe25-/-Tyr bonds in the B chain of insulin =

Synonyms

Aspartic proteinase, EC 3.4.4.1, elixir lactate of pepsin, fundus-pepsin, lactated pepsin, lactated pepsin elixir, P I, P-Ia, P-Ib, P-II, P-III, pep/PAG-L, pepsin, pepsin 1, pepsin A, pepsin A1, pepsin A2, pepsin D, pepsin fortior, Pepsin I/II, pepsin R, pepsinogen A, pepsinogen/PAG-Like, pepsins A1, pepsins A2, PG1, PG1-1, PG2, PG2-2, shewasin A, shewasin D

ECTree

     3 Hydrolases
         3.4 Acting on peptide bonds (peptidases)
             3.4.23 Aspartic endopeptidases
                3.4.23.1 pepsin A

Engineering

Engineering on EC 3.4.23.1 - pepsin A

Please wait a moment until all data is loaded. This message will disappear when all data is loaded.
PROTEIN VARIANTS
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
L291S
-
replacement of a pepsin A-specific residue by a chymosin-specific one. Decrease in hydrolysis of peptides with hydrophobic/aromatic residues at P’1 site, increase in hydrolysis of peptides with charged residues at P’1
L291S/L298Q
-
replacement of a pepsin A-specific residue by a chymosin-specific one. Decrease in hydrolysis of peptides with hydrophobic/aromatic residues at P’1 site, increase in hydrolysis of peptides with charged residues at P’1
L298Q
-
replacement of a pepsin A-specific residue by a chymosin-specific one. Decrease in hydrolysis of peptides with hydrophobic/aromatic residues at P’1 site, increase in hydrolysis of peptides with charged residues at P’1
M289D
-
replacement of a pepsin A-specific residue by a chymosin-specific one. Decrease in hydrolysis of peptides with hydrophobic/aromatic residues at P’1 site, increase in hydrolysis of peptides with charged residues at P’1
D215E
-
unlike wild-type, the mutant fusion protein is incapable of autocatalytic activation upon acidification of the medium, as determined by Western blot analysis. Mature mutant pepsin is obtained by processing fusion protein samples through an immobilized pepsin column. Tm-value of mutant enzyme is 65°C compared to 71°C for wild-type enzyme. The pH activity profiles of wild-type and mutant pepsin is similar. Mutant enzyme has a stronger affinity for the synthetic substrate KPAEFF(NO2)AL. Turnover number for mutant enzyme is significantly lower than that of the wild-type. kcat/Km is 1.9fold lower than wild-type value
D32E
-
unlike wild-type, the mutant fusion protein is incapable of autocatalytic activation upon acidification of the medium, as determined by Western blot analysis. Mature mutant pepsin is obtained by processing fusion protein samples through an immobilized pepsin column. Tm-value of mutant enzyme is 63°C compared to 71°C for wild-type enzyme. Pronounced decrease in activity below pH 2.5. Mutant enzyme has a stronger affinity for the synthetic substrate KPAEFF(NO2)AL. Turnover number for mutant enzyme is significantly lower than that of the wild-type. kcat/Km is 8.7fold lower than wild-type value
D32E/D215E
-
unlike wild-type, the mutant fusion protein is incapable of autocatalytic activation upon acidification of the medium, as determined by Western blot analysis. Mature mutant pepsin is obtained by processing fusion protein samples through an immobilized pepsin column. Tm-value of mutant enzyme is 63°C compared to 71°C for wild-type enzyme. The pH activity profiles of wild-type and mutant pepsin is similar. KM-value for KPAEFF(NO2)AL is not significantly different relative to wild-type. Turnover number for mutant enzyme is significantly lower than that of the wild-type. kcat/Km is fold lower than wild-type value. kcat/Km is 13.3fold lower than wild-type value
DELTA240-246/+GD
-
inactivation rate at pH 7.0 is 86% of that of the wild-type value. The Km-value for KPAEFF(NO2)AL is 2fold higher than that of the wild-type enzyme. The KM-value for LSF(NO2)-Nle-AL as substrate is 79% of the wild-type value
E244N/V246T
-
introduction of N-glycosylation site. Glycosylated mutant shows similar KM-value and substrate specificity as wild-type, but reduced catalytic efficiency
E287M
-
the ratio of turnover number to KM-value for KPILF(NO2)RL is 2.2fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPIEF(NO2)RL is 1.3fold higher than that of the wild-type enzyme,the ratio of turnover number to KM-value for KPIQF(NO2)RL is 1.6fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPIKF(NO2)RL is 60% of that of the wild-type enzyme, the ratio of turnover number to KM-value for KPPEF(NO2)RL is 90% of that of the wild-type enzyme
F111T/L112F
-
the ratio of turnover number to KM-value for KPILF(NO2)RL is 3.8fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPIEF(NO2)RL is 1.9fold higher than that of the wild-type enzyme,the ratio of turnover number to KM-value for KPIQF(NO2)RL is 2.3fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPIKF(NO2)RL is 1.7fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPPEF(NO2)RL is 2.9fold higher than that of the wild-type enzyme. Mutant enzyme cleaves SGGYDLSFLPQPPQE at one site Leu-Ser, compared to three sites cleaved by the wild-type enzyme, and at a rate 23fold higher than that of the wild-type enzyme
F111T/L112F/E287M
-
the ratio of turnover number to KM-value for KPILF(NO2)RL is 5.8fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPIEF(NO2)RL is 2.8fold higher than that of the wild-type enzyme,the ratio of turnover number to KM-value for KPIQF(NO2)RL is 2.8fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPIKF(NO2)RL is 1.1fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPPEF(NO2)RL is 3.7fold higher than that of the wild-type enzyme
F111T/L112F/T222V/E287M
-
the ratio of turnover number to KM-value for KPILF(NO2)RL is 3.5fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPIEF(NO2)RL is 2.4fold higher than that of the wild-type enzyme,the ratio of turnover number to KM-value for KPIQF(NO2)RL is 4.4fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPIKF(NO2)RL is 2.2fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPPEF(NO2)RL is 5.1fold higher than that of the wild-type enzyme
G2C/L167C
-
the mutation reduces the inactivation rate at pH 7.0 by 1.8times compared to wild-type value. The Km-value for KPAEFF(NO2)AL is 2.35fold higher than that of the wild-type enzyme. The KM-value for LSF(NO2)-Nle-AL as substrate is 95% of the wild-type value
G2S/D3Y
-
the mutation reduces the inactivation rate at pH 7.0 by 1.4times compared to wild-type value. The Km-value for KPAEFF(NO2)AL is 2.2fold higher than that of the wild-type enzyme. The KM-value for LSF(NO2)-Nle-AL as substrate is 1.5fold higher than that of the wild-type enzyme
G2S/D3Y/L10M/T12A/E13S
-
the mutation reduces the inactivation rate at pH 7.0 by 5.8times. In presence of glycerol and sucrose, this mutant shows a very low rate of inactivation, the residual activity after 240 min is 50% of the initial activity compared to the wild-type which loses most of its activity in 60 min. The Km-value for KPAEFF(NO2)AL is 2.4fold higher than that of the wild-type enzyme. The KM-value for LSF(NO2)-Nle-AL as substrate is 1.5fold higher than that of the wild-type enzyme
G76A
-
mutant enzyme with lower catalytic efficiency and is activated more slowly than the wild-type enzyme. The slower activation process is associated directly with altered proteolytic activity
G76S
-
mutant enzyme with lower catalytic efficiency and is activated more slowly than the wild-type enzyme. The slower activation process is associated directly with altered proteolytic activity
G76V
-
mutant enzyme with lower catalytic efficiency and is activated more slowly than the wild-type enzyme. The slower activation process is associated directly with altered proteolytic activity
G78(S)S79
-
differences in substrate specificity and catalytic activity
L10M/T12A/E13S
-
the mutation reduces the inactivation rate at pH 7.0 by 1.5times compared to wild-type value. The Km-value for KPAEFF(NO2)AL is 1.9fold higher than that of the wild-type enzyme. The KM-value for LSF(NO2)-Nle-AL as substrate is 2.2fold higher than that of the wild-type enzyme
S110N/L112T
-
introduction of N-glycosylation site. Glycosylated mutant shows similar KM-value and substrate specificity as wild-type, but reduced catalytic efficiency
S196R/D200G/E202K
-
inactivation rate at pH 7.0 is 86% of that of the wild-type value
S281N
-
introduction of N-glycosylation site. Glycosylated mutant shows similar KM-value and substrate specificity as wild-type, but reduced catalytic efficiency
S46K/D52N/N54K/Q55R/D60K
-
inactivation rate at pH 7.0 is 91% of that of the wild-type value
S46K/D52N/N54K/Q55R/D60K/S196R/D200G/E202K
-
the mutation reduces the inactivation rate at pH 7.0 by 2.3times compared to wild-type value. Km-value for KPAEFF(NO2)AL is 1.7fold higher than that of the wild-type enzyme. The KM-value for LSF(NO2)-Nle-AL as substrate is 1.6fold higher than that of the wild-type enzyme
T222V
-
the ratio of turnover number to KM-value for KPILF(NO2)RL is 2.5fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPIEF(NO2)RL is 1.1fold higher than that of the wild-type enzyme,the ratio of turnover number to KM-value for KPIQF(NO2)RL is 1.4fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPIKF(NO2)RL is equal to that of the wild-type enzyme, the ratio of turnover number to KM-value for KPPEF(NO2)RL is 1.9fold higher than that of the wild-type enzyme
T222V/E287M
-
the ratio of turnover number to KM-value for KPILF(NO2)RL is 4.1fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPIEF(NO2)RL is 2.6fold higher than that of the wild-type enzyme,the ratio of turnover number to KM-value for KPIQF(NO2)RL is 2.1fold higher than that of the wild-type enzyme, the ratio of turnover number to KM-value for KPIKF(NO2)RL is 80% of that of the wild-type enzyme, the ratio of turnover number to KM-value for KPPEF(NO2)RL is 2.9fold higher than that of the wild-type enzyme. Mutant enzyme cleaves site Ser-Phe in SGGYDLSFLPQPPQE at a rate 20fold higher than the wild-type enzyme
T77D
-
differences in substrate specificity and catalytic activity
T77D/G78(S)S79
-
double mutant, differences in substrate specificity and catalytic activity
T77N
-
introduction of N-glycosylation site. Glycosylated mutant shows similar KM-value and substrate specificity as wild-type, but reduced catalytic efficiency
additional information
-
two chain mutant