Disease relevance of ompF

• ChxR functions as a transcriptional regulator because it activated transcription of ompF and ompC when expressed in Escherichia coli [1].
• We have isolated a novel outer membrane protein (OMP)-encoding gene from Salmonella typhi (St), termed ompS1, using the ompF gene of Escherichia coli (Ec) as a heterologous probe [2].

High impact information on ompF

• DNase I protection studies showed that ChxR bound to sites in the ompF and ompC promoter proximal regions that overlap but were distinct from OmpR binding sites [1].
• Moreover, although phosphorylation increases the intrinsic binding of OmpR to a single OmpR-binding site, the primary role of phosphorylation in ompF regulation is to facilitate cooperative interactions between OmpR molecules bound at adjacent sites [3].
• We used DNA migration retardation analysis to examine the interactions of OmpR and the phosphorylated form of OmpR (OmpR-P) with the regulatory region immediately upstream of the ompF promoter [3].
• In addition, Northern analyses indicate that micF RNA and ompF mRNA levels are thermally regulated in several related species in a manner similar to the thermoregulation in Escherichia coli [4].
• The N-terminal end of the recognition helix is promoter-proximal and flanked by "wings" W1 and W2 positioned proximally and distally, respectively, to the transcription start site of ompF [5].

Biological context of ompF

• These results suggest that ompF and ompC expression is associated with other physiological regulating systems in addition to osmoregulation [6].
• Identification of the genes in multicopy plasmids affecting ompC and ompF expression in Escherichia coli [6].
• Using an E. coli genomic library in pUC19, we identified three clones whose products altered expression of ompC and ompF in response to medium osmolarity [6].
• The upstream DNA sequence of the S. marcescens gene was similar to the corresponding E. coli ompF sequence; however, a regulatory element important in repression of E. coli ompF at high osmolarity was absent [7].
• One class of mutants possessed alterations within the ompF gene while the rfa gene cluster, which is responsible for lipopolysaccharide (LPS) synthesis, was affected in the second class of mutants [8].

Associations of ompF with chemical compounds

• Mutational analysis of this construct reveals that the alteration of a conserved cytidine in the F1 motif (-86) causes a loss of OmpR affinity and disrupts hierarchical OmpR-binding in the entire ompF region [9].
• Indeed, multiple inputs and no single regulator were responsible for the high peak of ompF expression under glucose limitation [10].

References