Nucleic Acids Research Advance Access originally published online on October 16, 2007
Nucleic Acids Research 2007 35(21):7109-7117; doi:10.1093/nar/gkm773
Nucleic Acids Research, 2007, Vol. 35, No. 21 7109-7117
© 2007 The Author(s)
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/2.0/uk/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Molecular Biology |
In vivo assembling of bacterial ribosomal protein L11 into yeast ribosomes makes the particles sensitive to the prokaryotic specific antibiotic thiostrepton
Centro de Biología Molecular Severo Ochoa, Universidad Autónoma de Madrid and Consejo Superior de investigaciones Científicas, Cantoblanco, Madrid 28049, Spain
*To whom correspondence should be addressed. Tel: +34 91 4975076; Fax: +34 91 4974799; Email: jpgballesta{at}cbm.uam.es
Received August 13, 2007. Revised September 12, 2007. Accepted September 13, 2007.
Eukaryotic ribosomal stalk protein L12 and its bacterial orthologue L11 play a central role on ribosomal conformational changes during translocation. Deletion of the two genes encoding L12 in Saccharomyces cerevisiae resulted in a very slow-growth phenotype. Gene RPL12B, but not the RPL12A, cloned in centromeric plasmids fully restored control protein level and the growth rate when expressed in a L12-deprived strain. The same strain has been transformed to express Escherichia coli protein EcL11 under the control of yeast RPL12B promoter. The bacterial protein has been found in similar amounts in washed ribosomes from the transformed yeast strain and from control E. coli cells, however, EcL11 was unable to restore the defective acidic protein stalk composition caused by the absence of ScL12 in the yeast ribosome. Protein EcL11 induced a 10% increase in L12-defective cell growth rate, although the in vitro polymerizing capacity of the EcL11-containing ribosomes is restored in a higher proportion, and, moreover, the particles became partially sensitive to the prokaryotic specific antibiotic thiostrepton. Molecular dynamic simulations using modelled complexes support the correct assembly of bacterial L11 into the yeast ribosome and confirm its direct implication of its CTD in the binding of thiostrepton to ribosomes.