Open AccessThe crystallization of apo‐form UMP kinase from Xanthomonas campestris is significantly improved in a strong magnetic field
Author(s) -
Tu JheLe,
Chin KoHsin,
Wang Andrew H.J.,
Chou ShanHo
Publication year - 2007
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309107018787
Subject(s) - xanthomonas campestris , crystallization , physics , biology , genetics , bacteria , thermodynamics
Bacterial UMP kinases (UMPKs) are crucial enzymes that are responsible for microbial UTP biosynthesis. Interestingly, eukaryotic and prokaryotic cells use different enzymes for UMP‐phosphorylation reactions. Prokaryotic UMPKs are thus believed to be potential targets for antimicrobial drug development. Here, the cloning, expression and crystallization of SeMet‐substituted XC1936, a bacterial UMPK from Xanthomonas campestris pathovar campestris , are reported. The crystallization of the apo‐form UMPK was found to be significantly improved in a strong magnetic field; the crystals diffracted to a resolution of 2.35 Å, a dramatic improvement over the original value of 3.6 Å. Preliminary structural analyses of apo‐form XC1936 using crystals grown in a strong magnetic field clearly reveal well defined loop regions involved in substrate‐analogue binding that were previously not visible. Crystallization in a strong magnetic field thus was found to be indispensable in determining the flexible region of the XC1936 UMPK structure.