The Salmonella plasmid virulence spvABCD genes are growth phase regulated and require RpoS for maximal expression in stationary phase. We identified a growth phase-independent expression of spv which is mediated by short-chain fatty acids. During this fatty acid-mediated expression of spv, RpoS is required for induction only during exponential phase. In stationary phase, an rpoS-independent mec...

Bacteria living epiphytically on aerial plant surfaces encounter severe and rapidly fluctuating environmental conditions, and their capacity to withstand environmental stress contributes to epiphytic fitness. The stationary phase sigma factor RpoS is a key determinant in stress response of gram-negative bacteria, including Pseudomonas spp. This study focused on the role of RpoS in stress respon...

Hfq protein is vital for the function of many non-coding small (s)RNAs in bacteria but the mechanism by which Hfq facilitates the function of sRNA is still debated. We developed a fluorescence resonance energy transfer assay to probe how Hfq modulates the interaction between a sRNA, DsrA, and its regulatory target mRNA, rpoS. The relevant RNA fragments were labelled so that changes in intra- an...

Production of the secondary metabolite phenazine-1-carboxamide (PCN) by Pseudomonas chlororaphis PCL1391 is crucial for biocontrol activity against the phytopathogen Fusarium oxysporum f. sp. radicis lycopersici on tomato. Regulation of PCN production involves the two-component signalling system GacS/GacA, the quorum-sensing system PhzI/PhzR and the regulator PsrA. This paper reports that a fun...

Decorin-binding proteins B and A (DbpB and DbpA) are thought to play important roles in Borrelia burgdorferi pathogenesis by serving as adhesins for the extracellular matrix. It has been established that the expression of DbpBA is governed by the Rrp2-RpoN-RpoS regulatory pathway. However, the precise mechanism underlying the control of DbpBA expression has been unclear. In particular, it has b...

The S subunit of RNA polymerase, the product of the rpoS gene, controls the expression of genes responding to starvation and cellular stresses. Using gene array technology, we investigated rpoS-dependent expression at the onset of stationary phase in Escherichia coli grown in rich medium. Forty-one genes were expressed at significantly lower levels in an rpoS mutant derived from the MG1655 stra...

Quorum sensing, bacterial cell-to-cell communication with small signal molecules, controls the virulence of many pathogens. In contrast to other vibrios, neither the VanI/VanR acylhomoserine lactone quorum sensing system, nor the three-channel quorum sensing system affects virulence of the economically important aquatic pathogen Vibrio anguillarum. Indole is another molecule that recently gaine...

Mobile cranes have been used extensively as essential equipment at construction sites. The productivity improvement of the mobile crane affects overall project. Hence, various studies conducted regarding operation planning. However, on solving RCP (the repositioning problem) are insufficient. This article presents a reposition route planning optimization method (RPOS) that minimizes total opera...

Mutants of Salmonella enterica serovar Typhimurium resistant to fusidic acid (Fusr) have mutations in fusA, the gene encoding translation elongation factor G (EF-G). Most Fusr mutants have reduced fitness in vitro and in vivo, in part explained by mutant EF-G slowing the rate of protein synthesis and growth. However, some Fusr mutants with normal rates of protein synthesis still suffer from red...

Adaptive resistance of Pseudomonas aeruginosa to polymyxin B, a drug of last resort, is an emerging problem worldwide. The purpose of this study was to better understand the mechanism of transcriptional regulation of polymyxin B resistance in P. aeruginosa. One proposed regulatory pathway involved RpoS-activated PmrA which then activates ArnT, a lipid membrane modifier. We assessed the contribu...