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1pj9
From Proteopedia
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Bacillus circulans strain 251 loop mutant 183-195
Overview
Cyclodextrin glycosyltransferase (CGTase) catalyzes the formation of cyclodextrins from starch. Among the CGTases with known three-dimensional structure, Thermoanaerobacterium thermosulfurigenes CGTase has the highest thermostability. By replacing amino acid residues in the B-domain of Bacillus circulans CGTase with those from T. thermosulfurigenes CGTase, we identified a B. circulans CGTase mutant (with N188D and K192R mutations), with a strongly increased activity half-life at 60 degrees C. Asp188 and Arg192 form a salt bridge in T. thermosulfurigenes CGTase. Structural analysis of the B. circulans CGTase mutant revealed that this salt bridge is also formed in the mutant. Thus, the activity half-life of this enzyme can be enhanced by rational protein engineering.
About this Structure
1PJ9 is a Single protein structure of sequence from Bacillus circulans with , , , and as ligands. Active as Cyclomaltodextrin glucanotransferase, with EC number 2.4.1.19 Full crystallographic information is available from OCA.
Reference
Improved thermostability of bacillus circulans cyclodextrin glycosyltransferase by the introduction of a salt bridge., Leemhuis H, Rozeboom HJ, Dijkstra BW, Dijkhuizen L, Proteins. 2004 Jan 1;54(1):128-34. PMID:14705029
Page seeded by OCA on Thu Feb 21 14:29:20 2008
