Preparation, crystallization and preliminary X-ray analysis of YjcG protein from Bacillus subtilis

Bacillus subtilis YjcG is a functionally uncharacterized protein with 171 residues that has no structural homologue in the Protein Data Bank. However, it shows sequence homology to bacterial and archaeal 2'-5' RNA ligases. In order to identify its exact function via structural studies, the yjcG gene was amplified from B. subtilis genomic DNA and cloned into the expression vector pET21-DEST. The protein was expressed in a soluble form in Escherichia coli and was purified to homogeneity. Crystals suitable for X-ray analysis were obtained that diffracted to 2.3 A and belonged to space group C2, with unit-cell parameters a = 99.66, b = 73.93, c = 61.77 A, beta = 113.56 degrees.