PDBe 3tnx

X-ray diffraction
2.62Å resolution

Structure of the precursor of a thermostable variant of papain at 2.6 Angstroem resolution

Source organism: Carica papaya
Primary publication:
The structure of a thermostable mutant of pro-papain reveals its activation mechanism.
Acta Crystallogr. D Biol. Crystallogr. 68 1591-603 (2012)
PMID: 23151624

Function and Biology Details

Reaction catalysed:
Hydrolysis of proteins with broad specificity for peptide bonds, but preference for an amino acid bearing a large hydrophobic side chain at the P2 position. Does not accept Val in P1'. 
Biochemical function:
Biological process:
Cellular component:
  • not assigned

Structure analysis Details

Assembly composition:
monomeric (preferred)
Entry contents:
1 distinct polypeptide molecule
Papain Chains: A, C
Molecule details ›
Chains: A, C
Length: 363 amino acids
Theoretical weight: 41.07 KDa
Source organism: Carica papaya
Expression system: Escherichia coli
  • Canonical: P00784 (Residues: 27-345; Coverage: 98%)
Sequence domains:
Structure domains: Cysteine proteinases

Ligands and Environments

1 bound ligand:

No modified residues

Experiments and Validation Details

Entry percentile scores
X-ray source: ESRF BEAMLINE BM14
Spacegroup: P21
Unit cell:
a: 42.925Å b: 74.775Å c: 116.51Å
α: 90° β: 93.03° γ: 90°
R R work R free
0.186 0.183 0.236
Expression system: Escherichia coli