12-21 Table - link amino acids per second
||Bacteria Escherichia coli
||Bremer, H., Dennis, P. P. (1996) Modulation of chemical composition and other parameters of the cell by growth rate. Neidhardt, et al. eds. Escherichia coli and Salmonella typhimurium: Cellular and Molecular Biology, 2nd ed. chapter 97, p. 1559, Table 3
||(142) Young, R. and H. Bremer (1976). "Polypeptide-chain-elongation rate in Escherichia coli B/r as a function of growth rate." Biochem J 160:2: 185-94 (44) Dennis, P. P., and H. Bremer.Differential rate of ribosomal protein synthesis in Escherichia coli B/r. J Mol Biol. 1974 Apr 15 84(3):407-22. (49) Dennis, P. P., and M. Nomura. 1974. Stringent control of ribosomal protein gene expression in e.coli, PNAS 1974 Oct71(10):3819-23PubMed ID795428, 4618855, 4610562
||(Primary source 142 p.186 right column bottom paragraph:) "Bacterial protein was first uniformly pre-labelled
with [14C]leucine. At zero time, [3H]leucine was added to the exponentially growing culture and
samples were taken every 3s. After electrophoretic separation the 3H/14C ratios for proteins of various selected molecular weights were determined and each of these ratios was divided by the isotope ratio observed in total protein at the particular time. The quotient of these isotope ratios is designated F*
and is plotted as a function of the labelling time for each molecular-weight class (m, each class corresponding to a selected band on the gel). A theoretical treatment shows that these kinetics have a breakpoint at the time equal to the synthesis time of peptides of the molecular weight m (see the Appendix)." For succinate grown cells, cp (peptide-chain-elongation rate) is found to be 1330 daltons/s or 12.1 amino acids/s. For glucose and glucose/amino acids-grown cells, cp is 1880 daltons/s, or 17.1 amino acids/s.
||Note 'n' beneath table: "The peptide chain elongation rate, cp, was calculated in amino acid residues per second per ribosome from the rate of protein synthesis (dP/dt), the number of ribosomes (Nr), and the fraction of active ribosomes (ßr), using the relationship dP/dt=Nr×ßr×cp (see also the equivalent equation 5 in Table 5, primary sources 44, 49)." lower value is for slow division rate (100 minutes) and higher value is for fast division rate (24 minutes). See BNID 100233, 105067. For translation range of 2.2 and 29 aa/sec see Fluitt et al., 2007 PMID 17897886 p.346 left column heading "i"
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