Crystallization and preliminary x-ray diffraction study of cholera toxin B-subunit.
Cholera toxin binds to its ganglioside GM1 receptor via its B-subunit, a pentameric assembly of identical subunits (Mr = 11,600). Diffraction quality crystals of cholera toxin B-subunit have been obtained at room temperature by vapor diffusion with polyethylene glycol in the presence of the nonionic detergent beta-octyl glucoside. The crystals have been characterized with x-radiation as monoclinic, space group P21, with unit cell dimensions a = 39.0 A, b = 94.3 A, c = 67.5 A, beta = 96.0 degrees. There are two molecules per unit cell, with one molecule (Mr = 58,000) in each asymmetric unit. Precession photographs (micron = 13 degrees) show that crystals diffract beyond 3.3-A resolution and are stable in the x-ray beam at room temperature for at least 40 h; thus, they can be used to collect three-dimensional crystallographic data.
Maulik
P R
PR
Department of Medicine, Housman Medical Research Center, Boston University School of Medicine, Massachusetts 02118.
Reed
R A
RA
Shipley
G G
GG
D002772:Cholera Toxin / Q000302:isolation & purification; D011092:Polyethylene Glycols; D011487:Protein Conformation; D014961:X-Ray Diffraction
D011092:Polyethylene Glycols; D002772:Cholera Toxin