Number of σ28 molecules in exponential and stationary phase in E. coli W3110

Value 350 Copies/cell
Organism Bacteria Escherichia coli
Reference Jishage M, Iwata A, Ueda S, Ishihama A. Regulation of RNA polymerase sigma subunit synthesis in Escherichia coli: intracellular levels of four species of sigma subunit under various growth conditions. J Bacteriol. 1996 Sep178(18):5447-51. Table - link PubMed ID8808934
Method Cells were grown in LB medium at 37°C with shaking. At the middle of exponential growth phase, the levels of s subunits were determined by the quantitative Western blot system. The determination was repeated at least three times, and the values are the averages.
Comments Previously researchers estimated that the intracellular level of s70 subunit is about 700 molecules per E. coli W3350 cell throughout the change in growth phase (BNID 105160). Based on this number they calculate from s28/s70 ratio in table link [(85fmol/µgram)s28]/[(160fmol/µgram)s70] a number of 350 copies/cell of s28 [Calculation gives value of 370 copies/cell]
Entered by Uri M
ID 105167