A bacterial elongation factor G homologue exclusively functions in ribosome recycling in the spirochaete Borrelia burgdorferi.
Mol Microbiol
; 75(6): 1445-54, 2010 Mar.
Article
en En
| MEDLINE
| ID: mdl-20132446
ABSTRACT
Translation elongation factor G (EF-G) in bacteria plays two distinct roles in different phases of the translation system. EF-G catalyses the translocation of tRNAs on the ribosome in the elongation step, as well as the dissociation of the post-termination state ribosome into two subunits in the recycling step. In contrast to this conventional view, it has very recently been demonstrated that the dual functions of bacterial EF-G are distributed over two different EF-G paralogues in human mitochondria. In the present study, we show that the same division of roles of EF-G is also found in bacteria. Two EF-G paralogues are found in the spirochaete Borrelia burgdorferi, EF-G1 and EF-G2. We demonstrate that EF-G1 is a translocase, while EF-G2 is an exclusive recycling factor. We further demonstrate that B. burgdorferi EF-G2 does not require GTP hydrolysis for ribosome disassembly, provided that translation initiation factor 3 (IF-3) is present in the reaction. These results indicate that two B. burgdorferi EF-G paralogues are close relatives to mitochondrial EF-G paralogues rather than the conventional bacterial EF-G, in both their phylogenetic and biochemical features.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Ribosomas
/
Biosíntesis de Proteínas
/
Factor G de Elongación Peptídica
/
Borrelia burgdorferi
Límite:
Humans
Idioma:
En
Revista:
Mol Microbiol
Asunto de la revista:
BIOLOGIA MOLECULAR
/
MICROBIOLOGIA
Año:
2010
Tipo del documento:
Article
País de afiliación:
Japón