How big is an E. coli cell in litres?

The cell dry weight was calculated using a value of 173 µg per OD460 unit of one mL (BNID 106437). Strain used is B/r, a strain commonly used in early bacterial physiology studies. Values taken from F. C. Neidhardt, “Escherichia coli and Salmonella: Cellular and Molecular Biology”, Vol. 1., Chapter 3, ASM Press, 1996. read more

A bacterial cell is approximately 1 micrometre diam. Therefore one cell is approx. 1x10^-15 L - OR - 1 litre could contain 1x10^15 bacteria. Assumption close to spherical shape (actually E. coli is more elongated). read more

E. coli is a Gram-negative bacterium, and so it (like other Gram-negative bacteria) has an asymmetrical outer membrane, a space called the periplasm, an inner membrane, and the cytoplasm. Depending on the particular E. coli strain, the cell may also be surrounded by a polysaccharide capsule. read more