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.
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
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C
Abergel
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A
Rigal
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Chenivesse
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C
Lazdunski
J M
JM
Claverie
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Bouveret
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H
Bénédetti
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