Staphylococcus aureus
Molecular PathogenesisContribution of hla Regulation by SaeR to Staphylococcus aureus USA300 PathogenesisThe SaeRS two-component system in Staphylococcus aureus is critical for regulation of many virulence genes, including hla, which encodes alpha-toxin. However, the impact of regulation of alpha-toxin by Sae on S. aureus pathogenesis has not been directly addressed. Here, we mutated the SaeR-...
Cellular Microbiology: Pathogen-Host Cell Molecular InteractionsInfection of Primary Human Alveolar Macrophages Alters Staphylococcus aureus Toxin Production and ActivityPulmonary pathogens encounter numerous insults, including phagocytic cells designed to degrade bacteria, while establishing infection in the human lung. Staphylococcus aureus is a versatile, opportunistic pathogen that can cause severe pneumonia, and methicillin-resistant isolates are of particular concern.
Bacterial InfectionsContribution of YjbIH to Virulence Factor Expression and Host Colonization in Staphylococcus aureusTo persist within the host and cause disease, Staphylococcus aureus relies on its ability to precisely fine-tune virulence factor expression in response to rapidly changing environments. During an unbiased transposon mutant screen, we observed that disruption of a two-gene operon, yjbIH, resulted in decreased levels of pigmentation and aureolysin (Aur)...
Cellular Microbiology: Pathogen-Host Cell Molecular InteractionsDual Gene Expression Analysis Identifies Factors Associated with Staphylococcus aureus Virulence in Diabetic MiceStaphylococcus aureus is a major human pathogen of the skin. The global burden of diabetes is high, with S. aureus being a major complication of diabetic wound infections.
Molecular Pathogenesis | SpotlightControl of Staphylococcus aureus Quorum Sensing by a Membrane-Embedded Peptidase...Gram-positive bacteria process and release small peptides, or pheromones, that act as signals for the induction of adaptive traits, including those involved in pathogenesis. One class of small signaling pheromones is the cyclic autoinducing peptides (AIPs), which regulate expression of genes that orchestrate virulence and persistence in a range of microbes, including staphylococci, listeriae, clostridia, and enterococci.
Molecular Pathogenesis | SpotlightMroQ Is a Novel Abi-Domain Protein That Influences Virulence Gene Expression in Staphylococcus aureus via Modulation of Agr Activity...Numerous factors have, to date, been identified as playing a role in the regulation of Agr activity in Staphylococcus aureus, including transcription factors, antisense RNAs, and host elements. Herein we investigated the product of SAUSA300_1984 (termed MroQ), a transmembrane Abi-domain/M79 protease-family protein, as a novel effector of this system.
Bacterial InfectionsAlternative Enzyme Protection Assay To Overcome the Drawbacks of the Gentamicin Protection Assay for Measuring Entry and Intracellular Survival of StaphylococciPrecise enumeration of living intracellular bacteria is the key step to estimate the invasion potential of pathogens and host immune responses to understand the mechanism and kinetics of bacterial pathogenesis. Therefore, quantitative assessment of host-pathogen interactions is essential for development of novel antibacterial therapeutics for infectious disease.
Bacterial InfectionsRedundant and Distinct Roles of Secreted Protein Eap and Cell Wall-Anchored Protein SasG in Biofilm Formation and Pathogenicity of Staphylococcus aureusChronic and fatal infections caused by Staphylococcus aureus are sometimes associated with biofilm formation. Secreted proteins and cell wall-anchored proteins (CWAPs) are important for the development of polysaccharide-independent biofilms, but functional relationships between these proteins are unclear.
Bacterial InfectionsArtificial Selection for Pathogenicity Mutations in Staphylococcus aureus Identifies Novel Factors Relevant to Chronic InfectionAdaptation of Staphylococcus aureus to host microenvironments during chronic infection involves spontaneous mutations, yet changes underlying adaptive phenotypes remain incompletely explored. Here, we employed artificial selection and whole-genome sequencing to better characterize spontaneous chromosomal mutations that alter two pathogenicity phenotypes relevant to...
Molecular PathogenesisInterplay of Nitric Oxide Synthase (NOS) and SrrAB in Modulation of Staphylococcus aureus Metabolism and VirulenceStaphylococcus aureus nitric oxide synthase (saNOS) is a major contributor to virulence, stress resistance, and physiology, yet the specific mechanism(s) by which saNOS intersects with other known regulatory circuits is largely unknown. The SrrAB two-component system, which modulates gene expression in response to the reduced state of respiratory menaquinones, is a...