RiPS

Ribosomes Per Second

A standard unit to measure translational activity of an mRNA molecule.

RiPS per mRNA are equivalent to the rate of the limiting step in ribosome initiation and elongation. This has been estimated to be approximately 0.3s^-1 for the lac operon in E. coli[1]. De Smit et al.[2, 3] assumed a value of 0.5 ^-1

1. Kennell D and Riezman H. Transcription and translation initiation frequencies of the Escherichia coli lac operon. J Mol Biol. 1977 Jul;114(1):1-21. DOI:10.1016/0022-2836(77)90279-0 |