Open AccessCrystallization and preliminary X‐ray diffraction studies of the transcriptional repressor PaaX, the main regulator of the phenylacetic acid degradation pathway in Escherichia coli W
Author(s) -
RojasAltuve Alzoray,
CarrascoLópez César,
HernándezRocamora Víctor M.,
Sanz Jesús M.,
Hermoso Juan A.
Publication year - 2011
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309111029873
Subject(s) - phenylacetic acid , escherichia coli , repressor , monoclinic crystal system , bacteria , crystallization , regulator , chemistry , biochemistry , tetr , microbiology and biotechnology , biology , organic chemistry , molecule , transcription factor , gene , genetics
PaaX is the main regulator of the phenylacetic acid aerobic degradation pathway in bacteria and acts as a transcriptional repressor in the absence of its inducer phenylacetyl‐coenzyme A. The natural presence and the recent accumulation of a variety of highly toxic aromatic compounds owing to human pollution has created considerable interest in the study of degradation pathways in bacteria, the most important microorganisms capable of recycling these compounds, in order to design and apply novel bioremediation strategies. PaaX from Escherichia coli W was cloned, overexpressed, purified and crystallized using the sitting‐drop vapour‐diffusion method at 291 K. Crystals grew from a mixture of 0.9 M Li 2 SO 4 and 0.5 M sodium citrate pH 5.8. These crystals, which belonged to the monoclinic space group C 2 with unit‐cell parameters a = 167.88, b = 106.23, c = 85.87 Å, β = 108.33°, allowed the collection of an X‐ray data set to 2.3 Å resolution.