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Ribosome-associated protein that inhibits translation at the aminoacyl-tRNA binding stage.

ABSTRACT: We have recently isolated and characterized a novel protein associated with Escherichia coli ribosomes and named protein Y (pY). Here we show that the ribosomes from bacterial cells growing at a normal physiological temperature contain no pY, whereas a temperature downshift results in the appearance of the protein in ribosomes. The protein also appears in the ribosomes of those cells that reached the stationary phase of growth at a physiological temperature. Our experiments with cell-free translation systems demonstrate that the protein inhibits translation at the elongation stage by blocking the binding of aminoacyl-tRNA to the ribosomal A site. The function of the protein in adaptation of cells to environmental stress is discussed.

SUBMITTER: Agafonov DE

PROVIDER: S-EPMC1083885 | biostudies-literature | 2001 May

REPOSITORIES: biostudies-literature

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Ribosome-associated protein that inhibits translation at the aminoacyl-tRNA binding stage.

Agafonov D E DE Kolb V A VA Spirin A S AS

EMBO reports 20010501 5

We have recently isolated and characterized a novel protein associated with Escherichia coli ribosomes and named protein Y (pY). Here we show that the ribosomes from bacterial cells growing at a normal physiological temperature contain no pY, whereas a temperature downshift results in the appearance of the protein in ribosomes. The protein also appears in the ribosomes of those cells that reached the stationary phase of growth at a physiological temperature. Our experiments with cell-free transl ...[more]

PMID: 11375931

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