1TEC

CRYSTALLOGRAPHIC REFINEMENT BY INCORPORATION OF MOLECULAR DYNAMICS. THE THERMOSTABLE SERINE PROTEASE THERMITASE COMPLEXED WITH EGLIN-C

Summary for 1TEC

• Entry DOI: 10.2210/pdb1tec/pdb
• Descriptor: THERMITASE, EGLIN C, CALCIUM ION, ... (5 entities in total)
• Functional Keywords: complex(serine proteinase-inhibitor)
• Biological source: Thermoactinomyces vulgaris; More
• Cellular location: Secreted: P04072
• Total number of polymer chains: 2
• Total formula weight: 36588.05

Authors

Gros, P.,Dijkstra, B.W.,Hol, W.G.J. (deposition date: 1989-05-24, release date: 1989-10-15, Last modification date: 2024-02-14)

Primary citation

Gros, P.,Fujinaga, M.,Dijkstra, B.W.,Kalk, K.H.,Hol, W.G.
Crystallographic refinement by incorporation of molecular dynamics: thermostable serine protease thermitase complexed with eglin c.
Acta Crystallogr.,Sect.B, 45:488-499, 1989

PubMed Abstract: In order to investigate the principles of protein thermostability, the crystal structure of thermitase from Thermoactinomyces vulgaris, a thermostable member of the subtilisin family of serine proteases, has been determined in a complex with eglin c. Eglin c is a serine protease inhibitor from the leech Hirudo medicinalis. After data collection with a television area-detector diffractometer and initial structure solution by molecular-replacement methods, crystallographic refinement proceeded with incorporation of molecular-dynamics techniques. It appeared that this refinement procedure has a large convergence radius with movements of more than 5 A for many atoms. Two procedures for the crystallographic molecular-dynamics refinement have been tested. They differed mainly in time span and weight on the X-ray 'energy'. The best results were obtained with a procedure which allowed the molecular-dynamics technique to search a large area in conformational space by having less weight on the X-ray restraints and allowing more time. The use of molecular-dynamics refinement considerably simplified the laborious and difficult task of fitting the model in its electron density during the refinement process. The final crystallographic R factor is 17.9% at 2.2 A resolution.

PubMed: 2688688
DOI: 10.1107/S0108768189006038

Experimental method

X-RAY DIFFRACTION (2.2 Å)