PDBsum entry 1z7k

Hydrolase/hydrolase inhibitor

PDB id: 1z7k

Contents

Protein chains

223 a.a. *

62 a.a. *

Ligands

THR-ASN-GLU-GLU

NAG-NAG

Waters ×126

* Residue conservation analysis

PDB id:

1z7k

Name:

Hydrolase/hydrolase inhibitor

Title:

Crystal structure of trypsin- ovomucoid turkey egg white inhibitor complex

Structure:

Trypsin. Chain: a. Ovomucoid. Chain: b. Fragment: second domain, residues 2-63. Ovomucoid. Chain: c. Fragment: first domain, residues 1-4

Source:

Sus scrofa. Pig. Organism_taxid: 9823. Tissue: pancreas. Meleagris gallopavo. Turkey. Organism_taxid: 9103. Tissue: egg white. Tissue: egg white

Biol. unit:

Trimer (from PQS)

Resolution:

1.90Å R-factor: 0.172 R-free: 0.188

Authors:

B.Syed Ibrahim,V.Pattabhi

Key ref:

B.S.Ibrahim and V.Pattabhi (2004). Crystal structure of trypsin-turkey egg white inhibitor complex. Biochem Biophys Res Commun, 313, 8. PubMed id: 14672690 DOI: 10.1016/j.bbrc.2003.11.082

Date:

25-Mar-05 Release date: 05-Apr-05

Supersedes:

1r0t

Protein chain

P00761  (TRYP_PIG) -  Trypsin from Sus scrofa

Seq: 231 a.a.

Struc: 223 a.a.

Protein chain

P68390  (IOVO_MELGA) -  Ovomucoid from Meleagris gallopavo

Seq: 185 a.a.

Struc: 62 a.a.

Enzyme reactions

• Enzyme class: Chain A: E.C.3.4.21.4 - trypsin.
• Reaction: Preferential cleavage: Arg-|-Xaa, Lys-|-Xaa.

DOI no: 10.1016/j.bbrc.2003.11.082

Biochem Biophys Res Commun 313:8 (2004)

PubMed id: 14672690

Crystal structure of trypsin-turkey egg white inhibitor complex.

B.S.Ibrahim, V.Pattabhi.

ABSTRACT

Crystal structure of the complex between porcine beta-trypsin and the second domain of the Kazal-type ovomucoid turkey egg white trypsin inhibitor (OMTKY2) has been determined at 1.9A resolution. A peptide fragment from the first domain has been crystallized with the complex. Restrained-refinement of the structure led to an R-factor of 0.19 for the 32206 reflections. OMTKY2 exhibits the canonical Kazal-type fold with a central alpha-helix and a short two-stranded anti-parallel beta-sheet. The carbonyl carbon of the reactive site prefers trigonal geometry. The reactive site loop geometry of the inhibitor is complementary to the surface and charge of the binding site in beta-trypsin.