A5003249495- Antimicrobial Resistance in Staphylococcus
- Bacterial biofilms and quorum sensing
- Antimicrobial Peptides and Activities
- Biochemical and Structural Characterization
- Microbial Natural Products and Biosynthesis
- Bacterial Identification and Susceptibility Testing
- Mass Spectrometry Techniques and Applications
- RNA and protein synthesis mechanisms
- Probiotics and Fermented Foods
- Microfluidic and Capillary Electrophoresis Applications
- Microbial Metabolism and Applications
- Advanced Proteomics Techniques and Applications
- Bacterial Genetics and Biotechnology
- Bacteriophages and microbial interactions
- Genomics and Phylogenetic Studies
- Immune Response and Inflammation
- Microbial Metabolic Engineering and Bioproduction
- Glycosylation and Glycoproteins Research
- Fungal and yeast genetics research
- Microfluidic and Bio-sensing Technologies
- RNA Research and Splicing
- Biofuel production and bioconversion
- Enzyme Catalysis and Immobilization
- Electrohydrodynamics and Fluid Dynamics
- biodegradable polymer synthesis and properties
Duksung Women's University
2017-2025
National Institute of Allergy and Infectious Diseases
2012-2023
National Institutes of Health
2012-2023
Google (United States)
2016
Seoul National University
2003-2012
New York University
2012
Shanghai Medical College of Fudan University
2010
Biofilms cause significant problems in the environment and during treatment of infections. However, molecular mechanisms underlying biofilm formation are poorly understood. There is a particular lack knowledge about maturation processes, such as structuring detachment, which deemed crucial for maintenance viability dissemination cells from biofilm. Here, we identify phenol-soluble modulin (PSM) surfactant peptides key factors premier biofilm-forming pathogen Staphylococcus aureus . We...
The current pandemic of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) skin infections is caused by several genetically unrelated clones. Here, we analyzed virulence globally occurring CA-MRSA strains in a rabbit infection model. We used rabbits because neutrophils from this animal species have relatively high sensitivity to Panton-Valentine leukocidin (PVL), toxin epidemiologically correlated with many infections. Virulence the model vitro neutrophil lysis and...
Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) are causing an ongoing pandemic of mostly skin and soft tissue infections. The success CA-MRSA as pathogens is due to a combination antibiotic resistance with high virulence. In addition, it has been speculated that strains such the epidemic U.S. clone USA300 have increased capacity colonize human epithelia, owing bacteriocin-based bacterial interference. We here analyzed molecular basis antimicrobial activity...
Sepsis caused by Gram-positive bacterial pathogens is a major fatal disease but its molecular basis remains elusive. Toll-like receptor 2 (TLR2) has been implicated in the orchestration of inflammation and sepsis role appears to vary for different pathogen species clones. Accordingly, Staphylococcus aureus clinical isolates differ substantially their capacity activate TLR2. Here we show that strong TLR2 stimulation depends on high-level production phenol-soluble modulin (PSM) peptides...
Staphylococcus aureus (S. aureus) causes persistent biofilm-related infections. Biofilm formation by S. is affected the culture conditions and associated with certain genotypic characteristics. Here, we show that glucose sodium chloride (NaCl) supplementation of media, a common practice in studies biofilms vitro, influences both biofilm 40 clinical isolates (methicillin-resistant methicillin-sensitive variations quantification. Methicillin-resistant strains formed more robust than tryptic...
Hsf1 and Msn2/Msn4 transcription factors in Saccharomyces cerevisiae play important roles cellular homeostasis by activating gene expression response to multiple stresses including heat shock, oxidative stress nutrient starvation. Although it has been known that nuclear import of Msn2 is inhibited PKA-dependent phosphorylation, the mechanism for regulation not well understood. Here we demonstrate Yak1 kinase, which under negative control PKA, activates both phosphorylation when PKA activity...
The mechanisms used by the immune system to discriminate between pathogenic and commensal bacteria have remained largely unclear. Recently, we shown that virulence of Staphylococcus aureus depends on secretion phenol-soluble modulin (PSM) peptides disrupt neutrophils at micromolar concentrations. Moreover, all S. PSMs stimulate attract nanomolar concentrations via interaction with formyl-peptide receptor 2 (FPR2). Here, demonstrate FPR2 allows adjust their responses in relation...
The phenol-soluble modulin PSM-mec is the only known staphylococcal toxin that encoded on a mobile antibiotic resistance determinant, namely cassette chromosome (SCC) element mec encoding to methicillin. Here we show psm-mec gene found frequently among methicillin-resistant Staphylococcus aureus (MRSA) strains of SCCmec types II, III, and VIII, conserved part class A complex. Controlled expression AgrA versus RNAIII in agr mutants all 3 psm-mec-positive demonstrated psm-mec, which highly...
ABSTRACT Staphylococcus aureus is a leading cause of prosthetic joint infections, which, as we recently showed, proceed with the involvement biofilm-like clusters that recalcitrance to antibiotic treatment. Here analyzed why these grow extraordinarily large, reaching macroscopically visible extensions (>1 mm). We found while specific S. surface proteins are prerequisite for agglomeration in synovial fluid, low activity Agr regulatory system and subsequent production phenol-soluble modulin...
We demonstrate that mutation of the staphylococcal accessory regulator (sarA) limits accumulation alpha-toxin and phenol-soluble modulins (PSMs) in Staphylococcus aureus isolates USA300 clonal lineage. Degradation assays experiments done with protease inhibitors suggested this was due to increased production extracellular proteases rather than differences associated impact sarA on transcription target gene (hla) or (agr). This confirmed by demonstrating concomitant encoding aureolysin (aur)...
Bacterial sepsis is a major killer in hospitalized patients. Coagulase-negative staphylococci (CNS) with the leading species Staphylococcus epidermidis are most frequent causes of nosocomial sepsis, infectious isolates being methicillin-resistant. However, which bacterial factors underlie pathogenesis CNS unknown. While it has been commonly believed that invariant structures on surface trigger by causing an over-reaction immune system, we show here caused methicillin-resistant S. to large...
Phenol-soluble modulins (PSMs) are a family of peptides with multiple functions in staphylococcal pathogenesis. To gain insight into the structural features affecting PSM functions, we analyzed an alanine substitution library PSMα3, strongly cytolytic and proinflammatory Staphylococcus aureus significant contribution to S. virulence. Lysine residues were essential for both receptor-dependent receptor-independent activities. Both phenotypes also required additional features, C terminus being...
The emergence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is a growing cause for concern. These strains are more virulent than health care-associated MRSA (HA-MRSA) due to higher levels toxin expression. In previous study, we showed that the high-level expression PBP2a, alternative penicillin binding protein encoded by mecA gene on type II staphylococcal cassette chromosome mec (SCCmec) elements, reduced toxicity interfering with Agr quorum sensing system....
Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of morbidity and death. Phenol-soluble modulins (PSMs) are recently-discovered toxins with key impact on the development infections. Allelic variants PSMs their potential pathogen success during infection have not yet been described. Here we show that clonal complex (CC) 30 lineage, major hospital-associated sepsis hematogenous complications, expresses an allelic variant PSMα3 peptide. We found this variant, PSMα3N22Y,...