Open AccessPreliminary X‐ray crystallographic studies of Bacillus subtilis SpeA protein
Author(s) -
Liu XiaoYan,
Lei Jian,
Liu Xiang,
Su XiaoDong,
Li Lanfen
Publication year - 2009
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309109003856
Subject(s) - bacillus subtilis , crystallography , x ray , chemistry , materials science , biology , physics , bacteria , genetics , optics
The spe A gene in Bacillus subtilis encodes arginine decarboxylase, which catalyzes the conversion of arginine to agmatine. Arginine decarboxylase is an important enzyme in polyamine metabolism in B. subtilis . In order to further illustrate the catalytic mechanism of arginine decarboxylase by determining the three‐dimensional structure of the enzyme, the spe A gene was amplified from B. subtilis genomic DNA and cloned into the expression vector pET‐28a(+). SpeA was expressed in Escherichia coli and purified to homogeneity by nickel‐chelation chromatography followed by size‐exclusion chromatography. High‐quality crystals were obtained using the hanging‐drop vapour‐diffusion method at 289 K. The best crystal diffracted to 2.0 Å resolution and belonged to space group P 2 1 , with unit‐cell parameters a = 86.4, b = 63.3 c = 103.3 Å, β = 113.9°.