X-ray crystallographic studies of HemK from Thermotoga maritima, an N5-glutamine methyltransferase.
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%).
Yoon
Hye-Jin
HJ
Structural Proteomics Laboratory, School of Chemistry and Molecular Engineering, Seoul National University, Seoul 151-742, Korea.
Kang
Kyung Yi
KY
Ahn
Hyung Jun
HJ
Shim
Sun Mi
SM
Ha
Jun-Yong
JY
Lee
Soo-Kyoung
SK
Mikami
Bunzo
B
Suh
Se Won
SW
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*
D029968:Escherichia coli Proteins; D011994:Recombinant Proteins; D005973:Glutamine; D008780:Methyltransferases; D011496:Protein Methyltransferases; C092404:prmC protein, E coli