physiology
Research Article | Molecular Biology and PhysiologyParameters Affecting Continuous In Vitro Culture of Treponema pallidum StrainsSyphilis is caused by the bacterium Treponema pallidum subsp. pallidum. Until recently, this pathogen could only be maintained through infection of rabbits or other animals, making study of this important human pathogen challenging and costly. T. pallidum subsp. pallidum has now...
Research Article | Ecological and Evolutionary ScienceCarbon Use Efficiency and Its Temperature Sensitivity Covary in Soil BacteriaSoil microbes respond to environmental change by altering how they allocate carbon to growth versus respiration—or carbon use efficiency (CUE). Ecosystem and Earth System models, used to project how global soil C stocks will continue to respond to the climate crisis, often assume that microbes respond homogeneously to changes in the environment. In this study, we quantified how CUE varies with changes in temperature and substrate...
Research Article | Molecular Biology and PhysiologyThe TK0271 Protein Activates Transcription of Aromatic Amino Acid Biosynthesis Genes in the Hyperthermophilic Archaeon Thermococcus kodakarensisThe mechanisms of transcriptional regulation in archaea are still poorly understood. In this study, we identified a transcriptional regulator in the hyperthermophilic archaeon Thermococcus kodakarensis that activates the transcription of three operons involved in the biosynthesis of aromatic amino acids. The study represents one of only a few that identifies a...
Research Article | Molecular Biology and PhysiologyAggregation of Nontuberculous Mycobacteria Is Regulated by Carbon-Nitrogen BalanceFree-living bacteria can assemble into multicellular structures called biofilms. Biofilms help bacteria tolerate multiple stresses, including antibiotics and the host immune system. Nontuberculous mycobacteria are a group of emerging opportunistic pathogens that utilize biofilms to adhere to household plumbing and showerheads and to avoid phagocytosis by host immune cells. Typically, bacteria regulate biofilm formation by controlling...
Research Article | Host-Microbe BiologyA Tale of Three Species: Adaptation of Sodalis glossinidius to Tsetse Biology, Wigglesworthia Metabolism, and Host DietHuman African trypanosomiasis is caused by the Trypanosoma brucei parasite. The tsetse fly vector is of interest for its potential to prevent disease spread, as it is essential for T. brucei life cycle progression and transmission. The tsetse’s mutualistic endosymbiont...
- Research ArticleLong-Term In Vitro Culture of the Syphilis Spirochete Treponema pallidum subsp. pallidum
Syphilis, a sexually transmitted disease with a global distribution, is caused by a spiral-shaped bacterium called Treponema pallidum subspecies pallidum. Previously, T. pallidum was one of the few major bacterial pathogens...
- Research ArticleControl of gdhR Expression in Neisseria gonorrhoeae via Autoregulation and a Master Repressor (MtrR) of a Drug Efflux Pump Operon
The pathogenic Neisseria species are strict human pathogens that can cause a sexually transmitted infection (N. gonorrhoeae) or meningitis or fulminant septicemia (N. meningitidis). Although they share considerable genetic information, little attention has been directed to comparing transcriptional regulatory systems that modulate expression of their conserved genes. We hypothesized that transcriptional...