X-ray diffraction
1.58Å resolution

Crystal structure of a BPTI variant (Cys14->Ser) in complex with trypsin


Function and Biology Details

Structure analysis Details

Assemblies composition:
hetero dimer (preferred)
hetero octamer
hetero tetramer
Entry contents:
2 distinct polypeptide molecules
Macromolecules (2 distinct):
Cationic trypsin Chain: E
Molecule details ›
Chain: E
Length: 223 amino acids
Theoretical weight: 23.33 KDa
Source organism: Bos taurus
Expression system: Escherichia coli
  • Canonical: P00760 (Residues: 24-246; Coverage: 97%)
Sequence domains: Trypsin
Structure domains: Trypsin-like serine proteases
Pancreatic trypsin inhibitor Chain: I
Molecule details ›
Chain: I
Length: 58 amino acids
Theoretical weight: 6.51 KDa
Source organism: Bos taurus
Expression system: Escherichia coli HB101
  • Canonical: P00974 (Residues: 36-93; Coverage: 73%)
Sequence domains: Kunitz/Bovine pancreatic trypsin inhibitor domain
Structure domains: Pancreatic trypsin inhibitor Kunitz domain

Ligands and Environments

1 modified residue:

Experiments and Validation Details

Entry percentile scores
X-ray source: ENRAF-NONIUS FR591
Spacegroup: I222
Unit cell:
a: 74.783Å b: 82.435Å c: 123.965Å
α: 90° β: 90° γ: 90°
R R work R free
0.219 0.217 0.235
Expression systems:
  • Escherichia coli
  • Escherichia coli HB101