total in LB medium ~7800: total in MM medium ~2400: mean in LB medium 1.79: mean in MM medium 0.56 mRNA copies/cell
||Bacteria Escherichia coli
||Bartholomäus A et al., Bacteria differently regulate mRNA abundance to specifically respond to various stresses. Philos Trans A Math Phys Eng Sci. 2016 Mar 13 374(2063). pii: 20150069. doi: 10.1098/rsta.2015.0069. p.4 3rd paragraphPubMed ID26857681
||Abstract: "[Investigators] present a global analysis of the response of Escherichia coli to acute heat and osmotic stress. [They] combine deep sequencing of total mRNA and ribosome-protected fragments to provide a genome-wide map of the stress response at transcriptional and translational levels."
||P.4 3rd paragraph: "Cells grown in LB (Luria Bertani Broth, Lysogeny Broth) medium have about three times more mRNA transcripts than cells grown in MM (minimal medium, approx. 7800 mRNA copies/cell versus approx. 2400 mRNA copies/cell figure 1b) correlating to the 4× larger volume of cells cultured in LB. The mean mRNA copy number was 1.79 copies/cell in LB and 0.56 copies/cell in MM. Similar low overall mRNA copy numbers per cell have been theoretically predicted [ref 26] and experimentally determined in ensemble and single-cell measurements for another E. coli strain [ref 27]. Relatively low mRNA copies/cell have been reported also for budding [ref 28] and fission [ref 29] yeast yet the unicellular eukaryotes have on average an order of magnitude higher number of total mRNA molecules per cell which mirrors the larger cell volume and larger size of their genomes compared with E. coli."