Molecular Biology and Physiology
Research Article | Molecular Biology and PhysiologyRegulatory Mechanism of Nicotine Degradation in Pseudomonas putidaWe report the entire process underlying the NicR2 regulatory mechanism from association between free NicR2 and two promoters to dissociation of the NicR2-promoter complex. NicR2 can bind to another promoter, Pspm, which controls expression of nicotine-degrading genes that are not controlled by the Phsp promoter. We identified specific nucleotides of the Pspm promoter responsible for NicR2 binding. HSP was...
Research Article | Molecular Biology and PhysiologyA Stress Response Monitoring Lipoprotein Trafficking to the Outer MembraneThe outer membrane built by Gram-negative bacteria such as Escherichia coli forms a barrier that prevents antibiotics from entering the cell, limiting clinical options at a time of prevalent antibiotic resistance. Stress responses ensure that barrier integrity is continuously maintained. We have identified the Cpx signal transduction system as a stress response that...
Research Article | Molecular Biology and PhysiologyThe Leucine-Responsive Regulatory Protein Lrp Participates in Virulence Regulation Downstream of Small RNA ArcZ in Erwinia amylovoraFire blight disease continues to plague the commercial production of apples and pears despite more than a century of research into disease epidemiology and disease control. The causative agent of fire blight, Erwinia amylovora coordinates turning on or off specific virulence-associated traits at the appropriate time during disease development. The development of novel...
Research Article | Molecular Biology and PhysiologyIndole Reverses Intrinsic Antibiotic Resistance by Activating a Novel Dual-Function ImporterRecently, signaling molecules were found to play a role in mediating antibiotic resistance. In this study, we demonstrated that indole reversed the intrinsic antibiotic resistance (IRAR) of multiple bacterial species by promoting the expression of a novel dual-function importer. In addition, population-dependent...
Research Article | Molecular Biology and PhysiologyA Substrate-Activated Efflux Pump, DesABC, Confers Zeamine Resistance to Dickeya zeaeZeamines are a family of newly identified phytotoxins and potent antibiotics produced by D. zeae EC1. Unlike most bacterial organisms, which are highly sensitive, D. zeae EC1 is tolerant to zeamines, but the mechanisms involved are unknown. Our study showed, for the first time, that a new RND efflux pump, DesABC, is indispensable for D. zeae EC1 against zeamines. We found that the DesABC efflux pump was...
![Cytochrome P450 Monooxygenase-Mediated Metabolic Utilization of Benzo[<em>a</em>]Pyrene by <em>Aspergillus</em> Species](https://mbio.asm.org/sites/default/files/styles/thumbnail/public/externals/87a1b33830be69116cb130fcb2a68091.jpg?itok=ILcX07KB)
Research Article | Molecular Biology and PhysiologyCytochrome P450 Monooxygenase-Mediated Metabolic Utilization of Benzo[a]Pyrene by Aspergillus SpeciesWe are increasingly exposed to environmental pollutants, including the carcinogen benzo[a]pyrene (BaP), which has prompted extensive research into human metabolism of toxicants. However, little is known about metabolic mechanisms employed by fungi that are able to use some toxic pollutants as the substrates for growth, leaving innocuous by-products. This study systemically demonstrates that a common soil-dwelling fungus is able...
Research Article | Molecular Biology and PhysiologyThe Bacterial DNA Binding Protein MatP Involved in Linking the Nucleoid Terminal Domain to the Divisome at Midcell Interacts with Lipid MembranesThe division of an E. coli cell into two daughter cells with equal genomic information and similar size requires duplication and segregation of the chromosome and subsequent scission of the envelope by a protein ring, the Z-ring. MatP is a DNA binding protein that contributes both to the positioning of the Z-ring at midcell and the temporal control of nucleoid...
Research Article | Molecular Biology and PhysiologyImproper Coordination of BamA and BamD Results in Bam Complex Jamming by a Lipoprotein SubstrateThe β-barrel assembly machinery, the Bam complex, consists of five components, BamA to -E, among which BamA and BamD are highly conserved and essential. The nonessential components are believed to play redundant roles simply by improving the rate of β-barrel folding. Here we show that BamE contributes a specific and nonoverlapping function to the Bam complex. BamE coordinates BamA and BamD to form a complex between the lipoprotein RcsF...
Research Article | Molecular Biology and PhysiologyMetabolic Remodeling during Biofilm Development of Bacillus subtilisBacterial biofilms are ubiquitous in natural environments and play an important role in many clinical, industrial, and ecological settings. Although much is known about the transcriptional regulatory networks that control biofilm formation in model bacteria such as Bacillus subtilis, very little is known about the role of metabolism in this complex developmental...
Research Article | Molecular Biology and PhysiologyRobust Stoichiometry of FliW-CsrA Governs Flagellin Homeostasis and Cytoplasmic Organization in Bacillus subtilisThe intracellular concentration of flagellar filament protein Hag is restricted by the Hag-FliW-CsrA system in B. subtilis. Here we show that the Hag-FliW-CsrAdimer system functions at nearly 1:1:1 stoichiometry and that the system is both robust with respect to perturbation and hypersensitive to the Hag intracellular concentration. Moreover, restriction of...