Open AccessCrystallization and preliminary X‐ray analysis of FliJ, a cytoplasmic component of the flagellar type III protein‐export apparatus from Salmonella sp.
Author(s) -
Ibuki Tatsuya,
Shimada Masafumi,
Minamino Tohru,
Namba Keiichi,
Imada Katsumi
Publication year - 2009
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309108039882
Subject(s) - flagellum , crystallization , crystallography , cytoplasm , histidine , chemistry , protein crystallization , residue (chemistry) , serine , amino acid , biochemistry , enzyme , organic chemistry , gene
The axial component proteins of the bacterial flagellum are synthesized in the cytoplasm and then translocated into the central channel of the flagellum by the flagellar type III protein‐export apparatus for self‐assembly at the distal growing end of the flagellum. FliJ is an essential cytoplasmic component of the export apparatus. In this study, Salmonella FliJ with an extra three residues (glycine, serine and histidine) attached to the N‐terminus as the remainder of a His tag (GSH‐FliJ) was purified and crystallized. Crystals were obtained by the sitting‐drop vapour‐diffusion technique using PEG 300 as a precipitant. GSH‐FliJ crystals grew in the hexagonal space group P 6 1 22 or P 6 5 22. While the native crystals diffracted to 3.3 Å resolution, the diffraction resolution limit of mercury derivatives was extended to 2.1 Å. Anomalous and isomorphous difference Patterson maps of the mercury‐derivative crystal showed significant peaks in their Harker sections, indicating the usefulness of the derivative data for structure determination.