Disease relevance of osmE

• Characterization of the osmotically inducible gene osmE of Escherichia coli K-12 [1].
• A P. aeruginosa mutant incapable of growing anaerobically with nitrate or on arginine was fully complemented by the anr gene, indicating that it probably has a function in controlling anaerobic gene expression in Pseudomonas [2].

High impact information on osmE

• Nitrate, nitrite, nitric oxide and nitrous oxide reducing activities were expressed, and the structural genes for nitrite and nitric oxide reductases were transcribed under anaerobic conditions in the anr mutant strain transformed with the dnr gene [3].
• The osmE promoter was identified by both S1 nuclease and primer extension mapping of the 5' end of the osmE mRNA, by deletion analysis and by identification of a point mutation reducing its activity [1].
• A phi [osmEp-lac] operon fusion was constructed, and analysis of its expression demonstrated that osmE osmotic regulation probably occurs at the transcriptional level [1].
• The deduced amino acid sequence of the anr gene product showed considerable similarity to the FNR protein from E. coli [2].
• Transcriptional analysis of the anr gene showed that it is monocistronic but apparently lacks the equivalent sites for negative autoregulation which have been shown to be present in the promoter region of the E. coli fnr gene [2].

Chemical compound and disease context of osmE

• A 1.3-kb chromosomal fragment from P. aeruginosa complemented the anr mutation and also restored anaerobic growth of an Escherichia coli fnr deletion mutant on nitrate medium, indicating that the 1.3-kb fragment specifies an FNR-like regulatory protein [4].

Biological context of osmE

• The kinetics of osmEp transcription are discussed in light of the variations of DNA supercoiling [5].
• The anr mutation was mapped in the 60-min region of the P. aeruginosa chromosome [4].
• The effects of mutation of the anr gene on the aerobic respiratory chain of Pseudomonas aeruginosa [6].

Associations of osmE with chemical compounds

• The effect of such mutation and of novobiocin, an inhibitor of DNA gyrase, suggest that changes in DNA supercoiling are involved in the osmotic induction of osmEp [5].
• In this anr mutant, nitrate reductase and arginine deiminase were not induced by oxygen limitation [4].

References