Crystallization and preliminary crystallographic study of a component of the Escherichia coli tol system: TolB.
TolB from Escherichia coli is part of the Tol system used by the group A colicins to penetrate and kill cells. A TolB derivative tagged with six histidines was overexpressed, purified by chelation on a nickel affinity column and crystallized using the SAmBA software to define the optimal crystallization protocol. The crystals belong to the monoclinic system, space group P21 with unit-cell parameters a = 64.48, b = 41.06, c = 78.41 A, beta = 110.78 degrees. Frozen crystals diffract to 1.9 A resolution. Screening for heavy-atom derivatives both on the native TolB and various cysteine-substituted mutants is in progress. In addition, a selenomethionine-substituted protein is being produced in order to use the MAD method for structure determination.
Abergel
C
C
Information Génétique et Structurale, EP 91, Institut de Biologie Structurale et Microbiologie, 31 Chemin Joseph Aiguier, Marseille, 13402 CEDEX 20, France. chantal@igs.cnrs-mrs.fr
Rigal
A
A
Chenivesse
S
S
Lazdunski
C
C
Claverie
J M
JM
Bouveret
E
E
Bénédetti
H
H
D001426:Bacterial Proteins / Q000737:chemistry*; D003460:Crystallization; D018360:Crystallography, X-Ray; D003625:Data Collection; D004926:Escherichia coli; D029968:Escherichia coli Proteins; D006639:Histidine / Q000032:analysis; D033903:Periplasmic Proteins
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D033903:Periplasmic Proteins; C062094:tolB protein, E coli; D006639:Histidine