PDBe 1czi

X-ray diffraction
2.3Å resolution

Function and Biology Details

Reaction catalysed:
Broad specificity similar to that of pepsin A. Clots milk by cleavage of a single 104-Ser-Phe-|-Met-Ala-107 bond in kappa-chain of casein. 
Biological process:
Cellular component:
  • not assigned

Structure analysis Details

Assembly composition:
hetero dimer (preferred)
Entry contents:
2 distinct polypeptide molecules
Macromolecules (2 distinct):
Chymosin Chain: E
Molecule details ›
Chain: E
Length: 323 amino acids
Theoretical weight: 35.67 KDa
Source organism: Bos taurus
Expression system: Escherichia coli
UniProt:
  • Canonical: P00794 (Residues: 59-381; Coverage: 89%)
Gene names: CPC, CYM
Sequence domains: Eukaryotic aspartyl protease
Structure domains: Acid Proteases
CP-113972 (NORSTATINE-S-METHYL CYSTEINE-IODO-PHENYLALANINE-PROLINE) Chain: P
Molecule details ›
Chain: P
Length: 4 amino acids
Theoretical weight: 731 Da
Source organism: Synthetic construct
Expression system: Not provided
UniProt:

Ligands and Environments

No bound ligands

2 modified residues:

Experiments and Validation Details

Entry percentile scores
X-ray source: SRS BEAMLINE PX9.6
Spacegroup: R32
Unit cell:
a: 132.78Å b: 132.78Å c: 81.95Å
α: 90° β: 90° γ: 120°
R-values:
R R work R free
0.195 0.195 not available
Expression systems:
  • Escherichia coli
  • Not provided