Molecular Biology and Physiology
Research Article | Molecular Biology and PhysiologyThe Parameter-Fitness Landscape of lexA Autoregulation in Escherichia coliFeedback mechanisms are critical to control physiological responses. In gene regulation, one important example, termed negative autoregulation (NAR), occurs when a transcription factor (TF) inhibits its own production. NAR is common across the tree of life, enabling rapid homeostatic control of gene expression. NAR behavior can be described in accordance with its core biochemical parameters, but how constrained these parameters are by...
Research Article | Molecular Biology and PhysiologyCharacterization of Extracellular Vesicles Produced by Aspergillus fumigatus ProtoplastsFungal cells use extracellular vesicles (EVs) to export biologically active molecules to the extracellular space. In this study, we used protoplasts of Aspergillus fumigatus, a major fungal pathogen, as a model to evaluate the role of EV production in cell wall biogenesis. Our results demonstrated that wall-less...
Research Article | Molecular Biology and PhysiologyRedesigned TetR-Aptamer System To Control Gene Expression in Plasmodium falciparumMalaria elimination efforts have been repeatedly hindered by the evolution and spread of multidrug-resistant strains of Plasmodium falciparum. The absence of a commercially available vaccine emphasizes the need for a better understanding of Plasmodium biology in order to further translational research. This has been partly facilitated by targeted gene...
Research Article | Molecular Biology and PhysiologyIntegrative Analysis of Proteome and Transcriptome Dynamics during Bacillus subtilis Spore RevivalThis study demonstrated the progress of macromolecular synthesis during Bacillus subtilis spore germination and outgrowth. The transcriptome analysis has additionally allowed us to trace gene expression during this transformation process. For the first time, the basic survival kit for spore-based life has been identified. In addition, in this analysis based on...
Research Article | Molecular Biology and PhysiologyInvestigating Synthesis of the MalS Malic Enzyme during Bacillus subtilis Spore Germination and Outgrowth and the Influence of Spore Maturation and Sporulation ConditionsThe spores formed by Bacillus subtilis remain in a quiescent state for extended periods due to their dormancy and resistance features. Dormancy is linked to a very low level of core water content and a phase-bright state of spores. The present report, focusing on proteins MalS and PdhD (pyruvate dehydrogenase subunit D) and complementary to our companion report...
Research Article | Molecular Biology and PhysiologyF Plasmids Are the Major Carriers of Antibiotic Resistance Genes in Human-Associated Commensal Escherichia coliRising antibiotic resistance in human-associated bacterial pathogens is a serious threat to our ability to treat many infectious diseases. It is critical to understand how acquired resistance genes move in and through bacteria associated with humans, particularly for species such as Escherichia coli that are very common in the human gut but can also be dangerous...
Research Article | Molecular Biology and PhysiologyReading between the Lines: Utilizing RNA-Seq Data for Global Analysis of sRNAs in Staphylococcus aureusRegulatory small RNAs (sRNAs) are a class of RNA molecules that are produced in bacterial cells but that typically do not encode proteins. Instead, they perform a variety of critical functions within the cell as RNA. Most bacterial genomes do not include annotations for sRNA genes, and any type of analysis that is performed using a bacterial genome as a reference will therefore overlook data for sRNAs. In this study, we reexamined...
Commentary | Molecular Biology and PhysiologymSphere of Influence: Organoids and Single-Cell Sequencing, a Powerful Combination To Uncover Epithelial and Immune Cell Interactions in the Human Gut EnvironmentJose Lemme-Dumit works in the field of mucosal immunology and vaccines. In this mSphere of Influence article, he reflects on how two papers, “Long-term expansion of epithelial organoids from human colon, adenoma, adenocarcinoma, and Barrett’s epithelium” by Sato et al. (T. Sato, D. E. Stange, M. Ferrante, R. G. J. Vries, et al., Gastroenterology 141:1762–1772, 2011, https://doi.org/...
Research Article | Molecular Biology and PhysiologyCritical Role for Molecular Iron in Coxiella burnetii Replication and ViabilityHost organisms restrict the availability of iron to invading pathogens in order to reduce pathogen replication. To counteract the host’s response to infection, bacteria can rely on redundant mechanisms to obtain biologically diverse forms of iron during infection. C. burnetii appears specifically dependent on molecular iron for replication and viability and exhibits a...
Research Article | Molecular Biology and PhysiologyInterdependent YpsA- and YfhS-Mediated Cell Division and Cell Size Phenotypes in Bacillus subtilisBacillus subtilis is a rod-shaped Gram-positive model organism. The factors fundamental to the maintenance of cell shape and cell division are of major interest. We show that increased expression of ypsA results in cell division inhibition and impairment of colony formation on solid medium. Colonies that do arise possess compensatory suppressor mutations. We...