ISSN:
0887-3585
Keywords:
CytB
;
insecticide
;
cytolytic
;
purification
;
crystals
;
X-ray diffraction
;
Chemistry
;
Biochemistry and Biotechnology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Medicine
Notes:
CytB, a membrane pore-forming toxin from Bacillus thuringiensis subspecies kyushuensis, is specifically toxic to dipteran insect larvae but broadly cytolytic in vitro. It has been purified in the protoxin form from a recombinant Escherichia coli source and crystals have been obtained which diffract X-rays to at least 2.6 Å resolution. The tendency for CytB to aggregate in solution was overcome by including 50 mM of urea or 8 mM of ethanolamine during crystallization. Mutants designed to add or subtract single cysteine residues for the purpose of heavy atom derivative preparation were similarly purified and crystallized. The crystals are hexagonal bipyramids. They belong to space group P6122 (or P6522) with lattice constants a = b = 67.34 Å, c = 170.96 Å, and contain one molecule of the CytB protoxin (MW 29235) per asymmetric unit and 27% solvent by volume. © 1995 Wiley-Liss, Inc.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/prot.340230219
Permalink
