Periplasmic space

The periplasmic space or periplasm is a space between the peptidoglycan cell wall and inner membrane of Gram-negative bacteria or the equivalent space outside the inner membrane of Gram-positive bacteria. It may constitute up to 40% of the total cell volume in Gram-negative species, and is drastically smaller in Gram-positive species.[1] The space contains a loose network of murein (peptidoglycan) chains, as well as a gel containing hydrolytic and degradative enzymes.[2] In addition, it includes nutrient binding and transport proteins, hydrolytic proteins, and antibiotic resistance proteins. Other enzymes in the gel are involved in various biochemical pathways including peptidoglycan synthesis, electron transport, and alteration of substances toxic to the cell (xenobiotic metabolism).[3] In some species, the gel also contains beta-lactamase, an enzyme responsible for degrading penicillin. This can be of clinical importance when considering antibiotic resistance.

Other Usage

In yeast, the term "periplasmic space" refers to the thin region between the plasma membrane and the cell wall.

References

  1. ^ Otto Holst; Guntram Seltmann. The Bacterial Cell Wall. Berlin: Springer. ISBN 3-540-42608-6. 
  2. ^ Kenneth J. Ryan; C. George Ray (2004). Sherris Medical Microbiology: An Introduction to Infectious Diseases. New York: McGraw-Hill Medical Publishing Division. ISBN 0-8385-8529-9. 
  3. ^ Klein, Donald W.; Prescott, Lansing M.; Harley, John (2005). Microbiology. Boston: McGraw-Hill Higher Education. ISBN 0-07-295175-3. 

Further reading