metabolism
Research Article | Molecular Biology and PhysiologyA Toxoplasma Prolyl Hydroxylase Mediates Oxygen Stress Responses by Regulating Translation ElongationBecause oxygen plays a key role in the growth of many organisms, cells must know how much oxygen is available. O2-sensing proteins are therefore critical cellular factors, and prolyl hydroxylases are the best-studied type of O2-sensing proteins. In general, prolyl hydroxylases trigger cellular responses to decreased oxygen availability. But, how does a cell react to high levels of oxygen? Using the protozoan...
Research Article | Host-Microbe BiologyDissecting Flavivirus Biology in Salivary Gland Cultures from Fed and Unfed Ixodes scapularis (Black-Legged Tick)Tick-borne flaviviruses (TBFVs) are responsible for more than 15,000 human disease cases each year, and Powassan virus lineage 2 (POWV-L2) deer tick virus has been a reemerging threat in North America over the past 20 years. Rapid transmission of TBFVs in particular emphasizes the importance of preventing tick bites, the difficulty in developing countermeasures to prevent transmission, and the importance of understanding TBFV infection...
Research Article | Molecular Biology and PhysiologyDetermination of the Global Pattern of Gene Expression in Yeast Cells by Intracellular Levels of Guanine NucleotidesThis paper investigates whether, independently of the supply of any specific nutrient, gene transcription responds to the energy status of the cell by monitoring ATP and GTP levels. Short pathways for the inducible and futile consumption of ATP or GTP were engineered into the yeast Saccharomyces cerevisiae, and the effect of an increased demand for these purine...
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 Article | Host-Microbe BiologySupragingival Plaque Microbiome Ecology and Functional Potential in the Context of Health and DiseaseOral health has substantial economic importance, with over $100 billion spent on dental care in the United States annually. The microbiome plays a critical role in oral health, yet remains poorly classified. To address the question of how microbial diversity and function in the oral cavities of children relate to caries diagnosis, we surveyed the supragingival plaque biofilm microbiome in 44 juvenile twin pairs. Using shotgun sequencing...
Research Article | Molecular Biology and PhysiologySuppression of Drug Resistance Reveals a Genetic Mechanism of Metabolic Plasticity in Malaria ParasitesUnique and essential aspects of parasite metabolism are excellent targets for development of new antimalarials. An improved understanding of parasite metabolism and drug resistance mechanisms is urgently needed. The antibiotic fosmidomycin targets the synthesis of essential isoprenoid compounds from glucose and is a candidate for antimalarial development. Our report identifies a novel mechanism of drug resistance and further describes a...
Research Article | Molecular Biology and PhysiologyHelicobacter pylori Biofilm Involves a Multigene Stress-Biased Response, Including a Structural Role for FlagellaBiofilms, communities of bacteria that are embedded in a hydrated matrix of extracellular polymeric substances, pose a substantial health risk and are key contributors to many chronic and recurrent infections. Chronicity and recalcitrant infections are also common features associated with the ulcer-causing human pathogen H. pylori. However, relatively little is known...
- Observation | Host-Microbe BiologyEthanolamine Influences Human Commensal Escherichia coli Growth, Gene Expression, and Competition with Enterohemorrhagic E. coli O157:H7
The microbiota protects the host from invading pathogens by limiting access to nutrients. In turn, bacterial pathogens selectively exploit metabolites not readily used by the microbiota to establish infection. Ethanolamine has been linked to pathogenesis of diverse pathogens by serving as a noncompetitive metabolite that enhances pathogen growth as well as a signal that modulates virulence. Although ethanolamine is abundant in the...
- Research Article | Host-Microbe BiologyFormate Promotes Shigella Intercellular Spread and Virulence Gene Expression
Shigella is an intracellular pathogen that invades the human host cell cytosol and exploits intracellular nutrients for growth, enabling the bacterium to create its own metabolic niche. For Shigella to effectively invade and replicate within the host cytoplasm, it must sense and adapt to changing environmental conditions; however, the mechanisms and signals sensed by...
- Editor's Pick Research ArticleConvergent Metabolic Specialization through Distinct Evolutionary Paths in Pseudomonas aeruginosa
Only a few examples of real-time evolutionary investigations in environments outside the laboratory are described in the scientific literature. Remembering that biological evolution, as it has progressed in nature, has not taken place in test tubes, it is not surprising that conclusions from our investigations of bacterial evolution in the CF model system are different from what has been concluded from laboratory experiments. The...