HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Begic, S. Articles by Worobec, E. A. Search for Related Content PubMed PubMed Citation Articles by Begic, S. Articles by Worobec, E. A. Agricola Articles by Begic, S. Articles by Worobec, E. A.

Regulation of Serratia marcescens ompF and ompC porin genes in response to osmotic stress, salicylate, temperature and pH

Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2

Correspondence
Elizabeth A. Worobec
eworobe{at}ms.umanitoba.ca

Serratia marcescens is a Gram-negative enterobacterium that has become an important opportunistic pathogen, largely due to its high degree of natural antibiotic resistance. One factor contributing to this natural antibiotic resistance is reduced outer membrane permeability, which is controlled in part by OmpC and OmpF porin proteins. OmpF expression is regulated by micF, an RNA transcript encoded upstream of the ompC gene, which hybridizes with the ompF transcript to inhibit its translation. Regulation of S. marcescens porin gene expression, as well as that of micF, was investigated using -galactosidase reporter gene fusions in response to 5, 8 and 10 % sucrose, 1, 5 and 8 mM salicylate, and different pH and temperature values. -Galactosidase activity assays revealed that a lower growth temperature (28 °C), a more basic pH (pH 8), and an absence of sucrose and salicylate induce the transcription of the ompF gene, whereas the induction of ompC is stimulated at a higher growth temperature (42 °C), acidic pH (pH 6), and maximum concentrations of sucrose (10 %) and salicylate (8 mM). In addition, when multiple conditions were tested, temperature had the predominant effect, followed by pH. In this study, it was found that the MicF regulatory mechanism does not play a role in the osmoregulation of the ompF and ompC genes, whereas MicF does repress OmpF expression in the presence of salicylate and high growth temperature, and under low pH conditions.

This article has been cited by other articles:

				R. Pieper, S.-T. Huang, J. M. Robinson, D. J. Clark, H. Alami, P. P. Parmar, R. D. Perry, R. D. Fleischmann, and S. N. Peterson Temperature and growth phase influence the outer-membrane proteome and the expression of a type VI secretion system in Yersinia pestis Microbiology, February 1, 2009; 155(2): 498 - 512. [Abstract] [Full Text] [PDF]

				N. de Maria, A. Guevara, M. T. Serra, I. Garcia-Luque, A. Gonzalez-Sama, M. G. de Lacoba, M. R. de Felipe, and M. Fernandez-Pascual Putative Porin of Bradyrhizobium sp. (Lupinus) Bacteroids Induced by Glyphosate Appl. Envir. Microbiol., August 15, 2007; 73(16): 5075 - 5082. [Abstract] [Full Text] [PDF]