[Ribosome stability of Escherichia coli cells in amino acid starvation].
The dissociation of ribosomes from two isogenic pairs of Escherichia coli strains was studied during exponential growth, under amino acid starvation and subsequent chloramphenicol treatment. There were no significant differences in Mg2+-dependent dissociation of ribosomes from exponentially growing rel+ and rel- minus strains. The differences in dissociation of the ribosomes from rel+ and rel- minus cells were observed only upon amino acid starvation of these cultures. The dissociation of ribosomes from starved rel+ cells was more complete. After chloramphenicol treatment isolated ribosomes were more resistant to dissociation into subunits. Alterations of dissociation of the ribosomes in vitro correlated both with the amount of polysomes and the level of RNA synthesis in cells. It is proposed that rRNA synthesis in bacteria depends on the ratio of programmed and deprogrammed ribosomes.
D000332:Aerobiosis; D000596:Amino Acids / Q000378:metabolism*; D002413:Cations, Divalent; D002701:Chloramphenicol / Q000378:metabolism; D003470:Culture Media; D004926:Escherichia coli / Q000166:cytology* / Q000254:growth & development; D005827:Genetics, Microbial; D008274:Magnesium / Q000494:pharmacology; D011132:Polyribosomes / Q000378:metabolism; D012343:RNA, Transfer / Q000096:biosynthesis; D012270:Ribosomes / Q000378:metabolism*
D000596:Amino Acids; D002413:Cations, Divalent; D003470:Culture Media; D002701:Chloramphenicol; D012343:RNA, Transfer; D008274:Magnesium
Stabil'nost' ribosom kletok Escherichia coli pri aminokislotnom golodanii