Cloned (Comment) | Organism |
---|---|
His-tagged fusion protein stably transfected in LEXSY P10 host strain | Homo sapiens |
Crystallization (Comment) | Organism |
---|---|
super-activated legumain is crystallized in complex with the legumain-specific inhibitor Ala-Ala-Asn-chloromethylketone to resolution of 2.47 A | Homo sapiens |
Protein Variants | Comment | Organism |
---|---|---|
C189S | dead mutant: in contrast to the wild-type protein, no evidence for the additional C-terminal cleavage after Asp303/309 is found | Homo sapiens |
D303E/D309E | double mutant in which the pH 4-dependent cleavage site is disrupted | Homo sapiens |
DELTA18-25 | N-terminal truncation variant lacking the N-terminal propeptide [DELTA-(Val18-Asp25)] is created. The activity of this variant resembles that of the wild-type protein and it is inactive in the unprocessed form (Gly26-Tyr433) at pH 7.0 or pH 5.5. Like the wild-type protein, the truncation variant undergoes correct maturation at pH 5.5 to the Gly26-Asn323 form, confirming correct folding of the protein | Homo sapiens |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
Ac-Tyr-Val-Ala-Asp-chloromethylketone | the rate of inhibition by Asp-CMK is approximately 3times more rapid at pH 4.0 than at pH 5.5 | Homo sapiens | |
Ala-Ala-Asn-chloromethylketone | the rate of inhibition by Asn-CMK is approximately 1.3times more rapid at pH 5.5 than at pH 4.0 | Homo sapiens |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Homo sapiens | Q99538 | - |
- |
Posttranslational Modification | Comment | Organism |
---|---|---|
proteolytic modification | legumain is synthesized as a zymogen und undergoes pH-dependent autoproteolytic activation. All but one of the autocatalytic cleavage events occur in trans, with only the release of the C-terminal propeptide being relevant to enzymatic activity. Legumain matures to the fully active form (super-activation) only when incubated at pH 4.0 | Homo sapiens |
Purification (Comment) | Organism |
---|---|
using NiNTA chromatography | Homo sapiens |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
Ac-Tyr-Val-Ala-Asp-4-nitroanilide + H2O | - |
Homo sapiens | ? | - |
? | |
benzoyl-L-Arg-4-nitroanilide + H2O | - |
Homo sapiens | ? | - |
? |
Synonyms | Comment | Organism |
---|---|---|
legumain | - |
Homo sapiens |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
37 | - |
assay at | Homo sapiens |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
additional information | - |
legumain activity is pH-dependent and substrate-dependent | Homo sapiens |
4 | - |
Legumain activity shows a pH optimum of 4.0 towards substrates with Asp at the P1 position | Homo sapiens |
4 | - |
superactivation of prolegumain requires its incubation at pH 4.0 | Homo sapiens |
5.5 | - |
Legumain activity shows a pH optimum of 5.5 towards substrates with Asn at the P1 position: maximum activity towards substrate benzoyl-L-Arg-4-nitroanilide is observed at pH 5.5 | Homo sapiens |
pH Minimum | pH Maximum | Comment | Organism |
---|---|---|---|
5.5 | 7 | at neutral pH, full-length legumain remains stable with no indication of proteolytic processing. Shifting the pH to 5.5 the C-terminal propeptide Asp324-Tyr433 is cleaved within 20 h at 37°C | Homo sapiens |
pH Stability | pH Stability Maximum | Comment | Organism |
---|---|---|---|
4 | 5.5 | the thermal stability of active legumain is highest in the pH interval 4.0-5.5, with a melting temperature Tm of 60°C. At pH values higher than 6.0 the melting temperature Tm decreased to below 30°C | Homo sapiens |