1C9N

BACILLUS LENTUS SUBSTILISIN VARIANT (SER 87) K27R/V104Y/N123S/T274A

Summary for 1C9N

• Entry DOI: 10.2210/pdb1c9n/pdb
• Related: 1C13 1C9J
• Descriptor: Subtilisin Savinase, SULFATE ION, CALCIUM ION, ... (5 entities in total)
• Functional Keywords: subtiliin, altered flexibility, hydrolase, site-specific variant
• Biological source: Lederbergia lenta
• Cellular location: Secreted: P29600
• Total number of polymer chains: 1
• Total formula weight: 27101.81

Authors

Bott, R. (deposition date: 1999-08-02, release date: 1999-10-06, Last modification date: 2024-12-25)

Primary citation

Graycar, T.,Knapp, M.,Ganshaw, G.,Dauberman, J.,Bott, R.
Engineered Bacillus lentus subtilisins having altered flexibility.
J.Mol.Biol., 292:97-109, 1999

PubMed Abstract: The three-dimensional structures of engineered variants of Bacillus lentus subtilisin having increased enzymatic activity, K27R/N87S/V104Y/N123S/T274A (RSYSA) and N76D/N87S/S103A/V104I (DSAI), were determined by X-ray crystallography. In addition to identifying changes in atomic position we report a method that identifies protein segments having altered flexibility. The method utilizes a statistical analysis of variance to delineate main-chain temperature factors that represent significant departures from the overall variance between equivalent regions seen throughout the structure. This method reveals changes in main-chain mobility in both variants. Residues 125-127 have increased mobility in the RSYSA variant while residues 100-104 have decreased mobility in the DSAI variant. These segments are located at the substrate-binding site and changes in their mobility are believed to relate to the observed changes in proteolytic activity. The effect of altered crystal lattice contacts on segment flexibility becomes apparent when identical variants, determined in two crystal forms, are compared with the native enzyme.

PubMed: 10493860
DOI: 10.1006/jmbi.1999.3033

Experimental method

X-RAY DIFFRACTION (1.5 Å)