Functional analysis of the conserved histidine residue of Bamboo mosaic virus capping enzyme in the activity for the formation of the covalent enzyme-m7GMP intermediate.
The alphavirus-like mRNA capping enzyme of Bamboo mosaic virus (BaMV) exhibits an AdoMet-dependent guanylyltransferase activity by which the methyl group of AdoMet is transferred to GTP, leading to the formation of m(7)GTP, and the m(7)GMP moiety is next transferred to the 5' end of ppRNA via a covalent enzyme-m(7)GMP intermediate. The function of the conserved H68 of the BaMV capping enzyme in the intermediate formation was analyzed by mutagenesis in this study. The nature of the bond linking the enzyme and m(7)GMP was changed in the H68C mutant protein, strongly suggesting that H68 covalently binds to m(7)GMP in the intermediate.
Graduate Institute of Biotechnology, National Chung Hsing University, 250 Kuo-Kuang Rd., Taichung 40227, Taiwan, ROC.
Hua-Yang
HY
Lin
Chiao-Yuan
CY
Yu
Yau-Heiu
YH
Hsu
Menghsiao
M
Meng
D000595:Amino Acid Sequence; D001665:Binding Sites; D017124:Conserved Sequence; D006160:Guanosine Triphosphate / Q000737:chemistry; D006639:Histidine / Q000737:chemistry*; D019811:Hydroxylamine / Q000737:chemistry; D008780:Methyltransferases / Q000737:chemistry*; D008954:Models, Biological; D008969:Molecular Sequence Data; D009029:Mosaic Viruses / Q000378:metabolism*; D016296:Mutagenesis; D016297:Mutagenesis, Site-Directed; D010455:Peptides / Q000737:chemistry; D010957:Plasmids / Q000378:metabolism; D017863:Potexvirus / Q000378:metabolism*; D012315:RNA Caps / Q000737:chemistry*
D010455:Peptides; D012315:RNA Caps; D019811:Hydroxylamine; D006639:Histidine; D006160:Guanosine Triphosphate; C446079:16S rRNA - m7G methyltransferase; D008780:Methyltransferases