Differential expression of the OmpF and OmpC porin proteins in Escherichia coli K-12 depends upon the level of active OmpR.
نویسندگان
چکیده
We have generated a mutant form of the OmpR regulatory protein, OmpRD55E, that is active independent of the EnvZ kinase. Notably, the pattern of OmpF and OmpC expression can be altered simply by changing the level of this mutant protein in the cell. This result supports a key prediction of the current model of porin regulation, which states that the differential regulation of OmpF and OmpC is a direct consequence of the cellular level of the active form of OmpR.
منابع مشابه
Interaction of a transcriptional activator, OmpR, with reciprocally osmoregulated genes, ompF and ompC, of Escherichia coli.
The ompB locus, comprised of the genes ompR and envZ, regulates the expression of the genes ompF and ompC that encode the major porin proteins in the outer membrane of Escherichia coli K-12. OmpR is believed to activate transcription of ompF and ompC in a reciprocal manner depending upon the osmolarity of the culture medium. We were able to purify OmpR to homogeneity and to characterize its int...
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ورودعنوان ژورنال:
- Journal of bacteriology
دوره 180 1 شماره
صفحات -
تاریخ انتشار 1998