Osmotic regulation of porin expression: a role for DNA supercoiling

Graeme-Cook, K.A., May, G. , Bremer, E. and Higgins, C.F. (1989) Osmotic regulation of porin expression: a role for DNA supercoiling. Molecular Microbiology, 3(9), pp. 1287-1294. (doi:10.1111/j.1365-2958.1989.tb00279.x) (PMID:2552265)

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The OmpC and OmpF porins are major outer membrane proteins of Escherichia coli and Salmonella typhimurium. Their expression is affected by many environmental factors and by mutations in a variety of independent genes. The pair of regulatory proteins, OmpR and EnvZ, are required for normal porin expression. Despite intensive investigation, the mechanisms by which porin expression is regulated remain unclear. Mutations which alter supercoiling, as well as inhibitors of DNA gyrase, show that porin expression is extremely and specifically sensitive to the level of DNA supercoiling. Our data lead us to suggest that environmentally induced changes in DNA supercoiling may play a role in determining the level of porin expression. These findings have implications for current models of porin regulation.

Item Type:Articles (Letter)
Glasgow Author(s) Enlighten ID:May, Dr Gerhard
Authors: Graeme-Cook, K.A., May, G., Bremer, E., and Higgins, C.F.
Subjects:Q Science > QH Natural history > QH345 Biochemistry
Q Science > QH Natural history > QH426 Genetics
Q Science > QR Microbiology
College/School:College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing
Journal Name:Molecular Microbiology
ISSN (Online):1365-2958

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