Open AccessPurification, crystallization and preliminary X‐ray diffraction analysis of the carbohydrate‐binding region of the Streptococcus gordonii adhesin GspB
Author(s) -
Pyburn Tasia M.,
Yankovskaya Victoria,
Bensing Barbara A.,
Cecchini Gary,
Sullam Paul M.,
Iverson T. M.
Publication year - 2010
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309110036535
Subject(s) - streptococcus gordonii , bacterial adhesin , crystallization , x ray crystallography , crystallography , chemistry , diffraction , biochemistry , materials science , microbiology and biotechnology , streptococcus , biology , bacteria , genetics , gene , escherichia coli , optics , organic chemistry , physics
The carbohydrate‐binding region of the bacterial adhesin GspB from Streptococcus gordonii strain M99 (GspB BR ) was expressed in Escherichia coli and purified using affinity and size‐exclusion chromatography. Separate sparse‐matrix screening of GspB BR buffered in either 20 m M Tris pH 7.4 or 20 m M HEPES pH 7.5 resulted in different crystallographic behavior such that different precipitants, salts and additives supported crystallization of GspB BR in each buffer. While both sets of conditions supported crystal growth in space group P 2 1 2 1 2 1 , the crystals had distinct unit‐cell parameters of a = 33.3, b = 86.7, c = 117.9 Å for crystal form 1 and a = 34.6, b = 98.3, c = 99.0 Å for crystal form 2. Additive screening improved the crystals grown in both conditions such that diffraction extended to beyond 2 Å resolution. A complete data set has been collected to 1.3 Å resolution with an overall R merge value of 0.04 and an R merge value of 0.33 in the highest resolution shell.