Heterologous expression ofAquifex aeolicusribosome recycling factor inEscherichia coliis dominant lethal by forming a complex that lacks functional co-ordination for ribosome disassembly.

Autor:	Yamami, Tohru, Ito, Koichi, Fujiwara, Toshinobu, Nakamura, Yoshikazu
Předmět:	ESCHERICHIA coli RIBOSOMES ESCHERICHIA ORGANELLES GENETIC mutation BIOLOGICAL variation
Zdroj:	Molecular Microbiology; Jan2005, Vol. 55 Issue 1, p150-161, 12p
Abstrakt:	Recycling the post-termination ribosomal complex requires the co-ordinated effort of the ribosome, ribosome recycling factor (RRF) and elongation factor EF-G. AlthoughAquifex aeolicusRRF (aaRRF) bindsEscherichia coliribosomes as efficiently asE. coliRRF, the resulting complex is non-functional and dominant lethal inE. coli, even in the presence of homologousA. aeolicusEF-G. These findings suggest that theE. colipost-termination ribosomal complex with aaRRF lacks functional co-ordination with EF-G required for ribosome recycling. A chimeric EF-G (E. colidomains I–III,A. aeolicusdomains IV–V) or anA. aeolicusEF-G with distinct mutations in the domain I–II interface could activate aaRRF. Furthermore, novel mutations that localize to one surface of the L-shape structure of aaRRF restored activity inE. coli. These aaRRF mutations are spatially distinct from mutations previously described and suggest a novel active centre for coupling EF-G's G domain motor action to ribosome disassembly. [ABSTRACT FROM AUTHOR]
Databáze:	Complementary Index
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