Molecular Biology and Physiology
Research Article | Molecular Biology and PhysiologyThe Aspergillus fumigatus Mismatch Repair MSH2 Homolog Is Important for Virulence and Azole ResistanceInvasive aspergillosis (IA) has emerged as one of the most common life-threatening fungal diseases in immunocompromised patients, with mortality rates as high as 90%. Systemic fungal infections such as IA are usually treated with triazoles; however, epidemiological research has shown that the prevalence of azole-resistant Aspergillus fumigatus isolates has increased...
Research Article | Molecular Biology and PhysiologyThe Cross Talk between TbTim50 and PIP39, Two Aspartate-Based Protein Phosphatases, Maintains Cellular Homeostasis in Trypanosoma bruceiTrypanosoma brucei, the infectious agent of African trypanosomiasis, must adapt to strikingly different host environments during its digenetic life cycle. Developmental regulation of mitochondrial activities is an essential part of these processes. We have shown previously that mitochondrial inner membrane protein translocase 50 in...
Research Article | Molecular Biology and PhysiologyThe Glycosylphosphatidylinositol-Anchored DFG Family Is Essential for the Insertion of Galactomannan into the β-(1,3)-Glucan–Chitin Core of the Cell Wall of Aspergillus fumigatusThe fungal cell wall is a complex and dynamic entity essential for the development of fungi. It is composed mainly of polysaccharides that are synthetized by protein complexes. Enzymes involved in postsynthesis polysaccharide modifications, such as cleavage, elongation, branching, and cross-linking, are essential for fungal life. Here, we investigated in Aspergillus...
Research Article | Molecular Biology and PhysiologySignal Sensing and Transduction Are Conserved between the Periplasmic Sensory Domains of BifA and SagSBiofilms have been associated with more than 60% of all recalcitrant and chronic infections and can render bacterial cells up to a thousand times more resistant to antibiotics than planktonic cells. Although it is known that the transition from the planktonic to the biofilm mode of growth involves two-component regulatory systems, increased c-di-GMP levels, and quorum sensing systems among others, the exact signaling events that lead to...
Research Article | Molecular Biology and Physiology(p)ppGpp and CodY Promote Enterococcus faecalis Virulence in a Murine Model of Catheter-Associated Urinary Tract InfectionCatheter-associated urinary tract infections (CAUTIs) are one of the most frequent types of infection found in the hospital setting that can develop into serious and potentially fatal bloodstream infections. One of the infectious agents that frequently causes complicated CAUTI is the bacterium Enterococcus faecalis, a leading cause of hospital-acquired infections that...
Research Article | Molecular Biology and PhysiologyObservations of Shear Stress Effects on Staphylococcus aureus Biofilm FormationIt is well known that flow plays an important role in the formation, transportation, and dispersion of Staphylococcus aureus biofilms. What was heretofore not known was that the formation of tower structures in these biofilms is strongly shear stress dependent; there is, in fact, a narrow range of shear stresses in which the phenomenon occurs. This work quantifies the...
Research Article | Molecular Biology and PhysiologyFitness Restoration of a Genetically Tractable Enterococcus faecalis V583 Derivative To Study Decoration-Related Phenotypes of the Enterococcal Polysaccharide AntigenE. faecalis strain VE14089 was derived from V583 cured of its plasmids. Although VE14089 had no major DNA rearrangements, it presented significant growth and host adaptation differences from the reference strain V583 of our collection. To construct a strain with better fitness, we sequenced the genome of VE14089, identified single nucleotide polymorphisms (SNPs), and...
Observation | Molecular Biology and PhysiologyStaphylococcus aureus Coproporphyrinogen III Oxidase Is Required for Aerobic and Anaerobic Heme SynthesisHeme is a critical molecule required for aerobic and anaerobic respiration by organisms across kingdoms. The human pathogen Staphylococcus aureus has served as a model organism for the study of heme synthesis and heme-dependent physiology and, like many species of the phyla Firmicutes and Actinobacteria, generates heme through a coproporphyrin...
Research Article | Molecular Biology and PhysiologyThe Nuclear Export Receptors TbMex67 and TbMtr2 Are Required for Ribosome Biogenesis in Trypanosoma bruceiThe nuclear export of ribosomal subunits (60S and 40S) depends in part on the activity of the essential auxiliary export receptors TbMtr2 and TbMex67. When these proteins are individually depleted from the medically and agriculturally significant parasite Trypanosoma brucei, distinct alterations in the processing of the rRNAs of the large subunit (60S) are observed as...
Commentary | Molecular Biology and PhysiologymSphere of Influence: Ushering in the CRISPR Revolution to Toxoplasma BiologyAlfredo J. Guerra works in the field of molecular parasitology and structural biology. In this mSphere of Influence article, he reflects on how “Efficient Gene Disruption in Diverse Strains of Toxoplasma gondii Using CRISPR/CAS9” by Bang Shen et al. (mBio 5:e01114-14, 2014, https://doi.org/10.1128/mBio.01114-14) and...