title: Crystallization and preliminary X-ray crystallographic analysis of carboxyl-terminal region 4 of SigR from Streptomyces coelicolor A3(2).
abstract: Full-length SigR from Streptomyces coelicolor A3(2) was overexpressed in Escherichia coli, purified and submitted to crystallization trials using either polyethylene glycol 3350 or 4000 as a precipitant. X-ray diffraction data were collected to 2.60 Å resolution under cryoconditions using synchrotron X-rays. The crystal packs in space group P4₃2₁2, with unit-cell parameters a=b=42.14, c=102.02 Å. According to the Matthews coefficient, the crystal asymmetric unit cannot contain the full-length protein. Molecular replacement with the known structures of region 2 and region 4 as independent search models indicates that the crystal contains only the -35 element-binding carboxyl-terminal region 4 of full-length SigR. Mass-spectrometric analysis of the harvested crystal confirms this, suggesting a crystal volume per protein weight (VM) of 2.24 Å3 Da(-1) and 45.1% solvent content.
authors.affiliation: School of Systems Biomedical Science, Soongsil University, Seoul 156-743, Republic of Korea.
authors.forename: Keon Young
authors.initials: KY
authors.lastname: Kim
authors.affiliation: School of Systems Biomedical Science, Soongsil University, Seoul 156-743, Republic of Korea.
authors.forename: Sunmin
authors.initials: S
authors.lastname: Kim
authors.affiliation: School of Systems Biomedical Science, Soongsil University, Seoul 156-743, Republic of Korea.
authors.forename: Jeong Kuk
authors.initials: JK
authors.lastname: Park
authors.affiliation: School of Systems Biomedical Science, Soongsil University, Seoul 156-743, Republic of Korea.
authors.forename: HyoJin
authors.initials: H
authors.lastname: Song
authors.affiliation: School of Systems Biomedical Science, Soongsil University, Seoul 156-743, Republic of Korea.
authors.forename: SangYoun
authors.initials: S
authors.lastname: Park
mesh_terms: D003460:Crystallization; D018360:Crystallography, X-Ray; D048372:Streptomyces coelicolor / Q000737:chemistry*
keywords: ECF sigma factor; SigR; Streptomyces coelicolor A3(2)