E. coli ~0.3 - 3.0atm: Gram-positive bacteria such as B. subtilis and Staphylococcus aureus ∼20atm atm
||Mika JT, Schavemaker PE, Krasnikov V, Poolman B. Impact of osmotic stress on protein diffusion in Lactococcus lactis. Mol Microbiol. 2014 Nov94(4):857-70. doi: 10.1111/mmi.12800. p.858 left column top paragraphPubMed ID25244659
||Cayley, D.S., Guttman, H.J., and Record, M.T. (2000) Biophysical characterization of changes in amounts and activity of Escherichia coli cell and compartment water and turgor pressure in response to osmotic stress. Biophys J 78: 1748–1764. AND Whatmore, A.M., and Reed, R.H. (1990) Determination of turgor pressure in Bacillus subtilis: a possible role for K+ in turgor regulation. J Gen Microbiol 136: 2521–2526. AND Deng, Y., Sun, M., and Shaevitz, J.W. (2011) Direct measurement of cell wall stress stiffening and turgor pressure in live bacterial cells. Phys Rev Lett 107: 158101.PubMed ID10733957, 2127801, 22107320
||P.858 left column top paragraph:"Although the amount of quantitative data is limited, it is generally thought that the turgor of E. coli (∼ 3 atm) (primary source Cayley et al., 2000) is at least an order of magnitude lower than that of Gram-positive bacteria such as B. subtilis and Staphylococcus aureus (∼ 20 atm) (primary source Whatmore and Reed, 1990). More recent measurements indicate a turgor pressure for E. coli as low as ∼ 0.3 atm (primary source Deng et al., 2011). The higher turgor of Gram-positive bacteria must reflect a higher osmolyte concentration (e.g. K+ and counter ions) and consequently it will take a larger osmotic upshift to plasmolyse Gram-positive bacteria than Gram-negative cells. Depending on the elasticity of the cell wall, the impact of osmotic stress on crowding and protein diffusion could also be different in these organisms."