1TRY

STRUCTURE OF INHIBITED TRYPSIN FROM FUSARIUM OXYSPORUM AT 1.55 ANGSTROMS

Summary for 1TRY

• Entry DOI: 10.2210/pdb1try/pdb
• Descriptor: TRYPSIN, PHOSPHORYLISOPROPANE, ISOPROPYL ALCOHOL, ... (4 entities in total)
• Functional Keywords: hydrolase (serine proteinase)
• Biological source: Fusarium oxysporum
• Cellular location: Secreted: P35049
• Total number of polymer chains: 1
• Total formula weight: 22400.66

Authors

Rypniewski, W.R.,Dambmann, C.,Von Der Osten, C.,Dauter, M.,Wilson, K.S. (deposition date: 1994-03-07, release date: 1996-01-01, Last modification date: 2024-11-06)

Primary citation

Rypniewski, W.R.,Dambmann, C.,von der Osten, C.,Dauter, M.,Wilson, K.S.
Structure of inhibited trypsin from Fusarium oxysporum at 1.55 A.
Acta Crystallogr.,Sect.D, 51:73-85, 1995

PubMed Abstract: The structure of trypsin from the fungus Fusarium oxysporum has been refined at 1.55 A resolution by restrained least-squares minimization to an R-factor of 14.4%. The data were recorded from a single-crystal on the X31 beamline at EMBL, Hamburg, using a locally developed image-plate scanner. The final model consists of 1557 protein atoms, 400 water molecules, one molecule of isopropanol and one monoisopropyl phosphoryl inhibitor group covalently bound to the catalytic Ser195. Comparison of the structure with bovine trypsin reveals significant differences in the active site and suggests a possible explanation for the difference in substrate specificity between the two enzymes. In F. oxysporum trypsin the specificity pocket is larger than in bovine trypsin. This explains the preference of F. oxysporum trypsin for the bulkier arginine over lysine and the reverse preference in bovine trypsin. The binding cavity on the C-terminal side of the substrate is more restricted in F. oxysporum trypsin than in mammalian and Streptomyces griseus trypsins, which explains the relative inactivity of F. oxysporum trypsin towards peptide-pNA substrate analogues as an unfavourable steric interaction between the side of the binding cavity and the para-nitroanilino group of peptide-pNA. The observed restriction of the binding cavity does not lead to a reduced catalytic activity compared to other trypsins.

PubMed: 15299338
DOI: 10.1107/S0907444994009169

Experimental method

X-RAY DIFFRACTION (1.55 Å)