Mastrangelo Eloise, Bollati Michela, Milani Mario, de Lamballerie Xavier, Brisbarre Nadège, Dalle Karen, Lantez Violaine, Egloff Marie Pierre, Coutard Bruno, Canard Bruno, Gould Ernest, Forrester Naomi, Bolognesi Martino
Department of Biomolecular Sciences and Biotechnology, CNR-INFM, University of Milano, Via Celoria 26, 20133 Milano, Italy.
Acta Crystallogr Sect F Struct Biol Cryst Commun. 2006 Aug 1;62(Pt 8):768-70. doi: 10.1107/S1744309106025553. Epub 2006 Jul 24.
Viral methyltranferases (MTase) are involved in the third step of the mRNA-capping process, transferring a methyl group from S-adenosyl-L-methionine (SAM) to the capped mRNA. MTases are classified into two groups: (guanine-N7)-methyltransferases (N7MTases), which add a methyl group onto the N7 atom of guanine, and (nucleoside-2'-O-)-methyltransferases (2'OMTases), which add a methyl group to a ribose hydroxyl. The MTases of two flaviviruses, Meaban and Yokose viruses, have been overexpressed, purified and crystallized in complex with SAM. Characterization of the crystals together with details of preliminary X-ray diffraction data collection (at 2.8 and 2.7 angstroms resolution, respectively) are reported here. The sequence homology relative to Dengue virus 2'OMTase and the structural conservation of specific residues in the putative active sites suggest that both enzymes belong to the 2'OMTase subgroup.
病毒甲基转移酶（MTase）参与mRNA加帽过程的第三步，将甲基从S-腺苷-L-甲硫氨酸（SAM）转移到加帽的mRNA上。MTase分为两组：（鸟嘌呤-N7）-甲基转移酶（N7MTase），将甲基添加到鸟嘌呤的N7原子上；以及（核苷-2'-O-）-甲基转移酶（2'OMTase），将甲基添加到核糖羟基上。两种黄病毒——梅阿班病毒和横濑病毒的MTase已被过量表达、纯化，并与SAM形成复合物进行结晶。本文报道了晶体的表征以及初步X射线衍射数据收集的详细情况（分辨率分别为2.8埃和2.7埃）。相对于登革病毒2'OMTase的序列同源性以及假定活性位点中特定残基的结构保守性表明，这两种酶都属于2'OMTase亚组。
