Biochemical and phylogenetic analyses of methionyl‐tRNA synthetase isolated from a pathogenic microorganism, Mycobacterium tuberculosis

FEBS Letters

Martinis, Susan A³  Motegi, Hiromi¹  Lee, Sang Ho³  Shiba, Kiyotaka¹  Sassanfar, Mandana³  Jo, Yeong Joon²  Kim, Sunghoon² 

[1] Cancer Institute, Department of Cell Biology, 1-37-1 Kami-Ikebukuro, Toshima-ku, Tokyo 170, Japan;Sung Kyun Kwan University, Department of Biology, 300 Chunchundong, Jangangu, Suwon, Kyunggido 440-746, South Korea;Cubist Pharmaceutical, 24 Emily Street, Cambridge, MA 02139, USA

关键词: Methionyl-tRNA synthetase;    Zn2+ binding motif;    Dimerization;    Phylogeny;    Mycobacterium tuberculosis;   

DOI  :  10.1016/S0014-5793(98)00417-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Mycobacterium tuberculosis methionyl-tRNA synthetase (MetRS) has been cloned and characterized. The protein contains class I signature sequences but lacks the Zn²⁺ binding motif and the C-terminal dimerization appendix that are found in MetRSs from several organisms including E. coli MetRS. Consistent with these features, the enzyme behaved as a monomer in a gel filtration chromatography and did not contain the bound Zn²⁺. Nonetheless, it was active to the tRNA^Met of E. coli as determined by in vivo genetic complementation and in vitro reaction. Phylogenetic analysis separated the M. tuberculosis and E. coli MetRSs into prokaryote and eukaryote-archaea group, respectively. This result is consistent with the taxonomic locations of the organism but is an interesting contrast to the case of its paralogous protein, isoleucyl-tRNA synthetase, and suggests that the two enzymes evolved in separate idiosyncratic pathways.

【 授权许可】

Unknown