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The composition of an unusual precursor of 50 S ribosomes in a mutant of Escherichia coli.

ABSTRACT: Escherichia coli strain 15--28 is a mutant which during exponential growth contains large amounts of a '47S' ribonucleoprotein precursor to 50S ribosomes. The '47S particles' are more sensitive to ribonuclease than are 50S ribosomes. The 23 S RNA of 47S particles may be slightly undermethylated, but cannot be distinguished from the 23S RNA of 50S ribosomes by sedimentation or electrophoresis. Isolated particles have 10--15% less protein than do 50S ribosomes; proteins L16, L28 and L33 are absent. Comparison with precursor particles studied by other workers in wild-type strains of E. coli suggests that the assembly of 50S ribosomes in strain 15--28 is atypical.

SUBMITTER: Markey F

PROVIDER: S-EPMC1163988 | biostudies-other | 1976 Aug

REPOSITORIES: biostudies-other

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An unusual precursor of 50S ribosomes in a mutant of Escherichia coli.

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Binding of chloramphenicol and a fragment of aminoacyl-transfer ribonucleic acid to ribosomes and a ribosome precursor from a mutant of Escherichia coli.

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