title: X-ray crystallographic studies of HemK from Thermotoga maritima, an N5-glutamine methyltransferase.
abstract: The enzyme HemK (or PrmC) is one of the first identified methyltransferases that modify glutamine. It methylates the highly conserved GGQ motif in class I release factors (RF1 and RF2) in Escherichia coli. HemK from Thermotoga maritima was over-expressed and crystallized in the presence of S-adenosylmethionine at 296 K using ammonium sulfate as the precipitant. X-ray diffraction data were collected to 2.5 A resolution from a native crystal. The crystal is orthorhombic, belonging to the space group I222 (or I2(1)2(1)2(1)), with unit-cell parameters of a = 104.24, b = 118.73, and c = 146.62 A. Two (or three) monomers of recombinant HemK are likely to be present in the crystallographic asymmetric unit, giving a V(M) of 3.62 A3 Da(-1) (or 2.41 A3 Da(-1)), with a solvent content of 62.7% (or 44.0%).
authors.affiliation: Structural Proteomics Laboratory, School of Chemistry and Molecular Engineering, Seoul National University, Seoul 151-742, Korea.
authors.forename: Hye-Jin
authors.initials: HJ
authors.lastname: Yoon
authors.forename: Kyung Yi
authors.initials: KY
authors.lastname: Kang
authors.forename: Hyung Jun
authors.initials: HJ
authors.lastname: Ahn
authors.forename: Sun Mi
authors.initials: SM
authors.lastname: Shim
authors.forename: Jun-Yong
authors.initials: JY
authors.lastname: Ha
authors.forename: Soo-Kyoung
authors.initials: SK
authors.lastname: Lee
authors.forename: Bunzo
authors.initials: B
authors.lastname: Mikami
authors.forename: Se Won
authors.initials: SW
authors.lastname: Suh
mesh_terms: D003460:Crystallization; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins / Q000737:chemistry*; D005973:Glutamine / Q000737:chemistry*; D008780:Methyltransferases / Q000737:chemistry*; D011496:Protein Methyltransferases / Q000737:chemistry*; D011994:Recombinant Proteins / Q000737:chemistry*; D020124:Thermotoga maritima / Q000737:chemistry*
chemical_list: D029968:Escherichia coli Proteins; D011994:Recombinant Proteins; D005973:Glutamine; D008780:Methyltransferases; D011496:Protein Methyltransferases; C092404:prmC protein, E coli