Pressure‐induced dissociation of tight couple ribosomes

FEBS Letters

Jaenicke, Rainer¹  Groß, Michael¹ 

[1] Institut für Biophysik und Physikalische Biochemie, Universität Regensburg, D-8400 Regensburg, FRG

关键词: Elongation cycle;    High pressure;    Light scattering;    Ribosome;    Subunit dissociation;    Tight couple;   

DOI  :  10.1016/0014-5793(90)80934-B

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Ribosomes from Escherichia coli have been shown to undergo subunit dissociation at elevated hydrostatic pressure. This holds for both crude and highly purified ribosomes. No inhibitory effect could be detected by addition of either the S100 supernatant, or tRNA, polyuridylic acid, and spermine. Light scattering experiments at pressures up to 1000 bar reveal different susceptibility of tight couple and loose couple ribosomes toward pressure dissociation. Tight couples are subjected to EF-Tu-catalyzed binding of aminoacyl-tRNA, thus yielding a model system of the elongating ribosome before the peptidyl transfer step. High pressure dissociation of this compound suggests that enzymatic binding converts tight couples into loose couples. A hypothesis referring to conformational changes during the elongation cycle is presented.

【 授权许可】

Unknown