Periplasmic space in Salmonella typhimurium and Escherichia coli

Jeffry Benton Stock, B. Rauch, S. Roseman

Research output: Contribution to journalArticle

304 Scopus citations

Abstract

The volume of the periplasmic space in E. coli and S. typhimurium cells was measured. This space, in cells grown and collected under conditions routinely used in work with these bacteria, was shown to comprise from 20 to 40% of the total cell volume. Further studies were conducted to determine the osmotic relationships between the periplasm, the external milieu, and the cytoplasm. Results showed that there is a Donnan equilibrium between the periplasm and the extracellular fluid, and that the periplasm and cytoplasm are isoosmotic. In minimal salts medium, the osmotic strength of the cell interior was estimated to be approximately 300 mosM, with a net pressure of approximately 3.5 atm being applied to the cell wall. A corollary of these findings was that an electrical potential exists across the outer membrane. This potential was measured by determining the distributions of Na + and Cl - between the periplasm and the cell exterior. The potential varied with the ionic strength of the medium; for cells in minimal salts medium it was approximately 30 mV, negative inside.

Original languageEnglish (US)
Pages (from-to)7850-7861
Number of pages12
JournalJournal of Biological Chemistry
Volume252
Issue number21
StatePublished - Dec 1 1977
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Biochemistry

Fingerprint Dive into the research topics of 'Periplasmic space in Salmonella typhimurium and Escherichia coli'. Together they form a unique fingerprint.

  • Cite this