Applied Microbiology: Open Access
Open Access
ISSN: 2471-9315
+44 1300 500008
ISSN: 2471-9315
+44 1300 500008
Soo-Jin Yang
Chung-Ang University, Republic of Korea
Posters & Accepted Abstracts: Appli Micro
Statement of the Problem: The livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) persist within livestock population and can serve as a reservoir for human infection. The persistence and transmission of LA-MRSA infections between human and animal hosts require the pathogen to overcome host innate immune response, especially the bactericidal action of host defense cationic antimicrobial peptides (HD-CAPs). In this investigation, the potential genotypic and phenotypic factors associated with resistance to HD-CAPs were assessed using animal and human-originated MRSA strains. Methodology & Theoretical Orientation: The 9 LA-MRSA strains isolated from bovine mastitis and 10 MRSA strains isolated from human patients were used to assess: (1) HD-CAP susceptibility to the human cathelicidin (LL-37), polymyxin B and daptomycin; (2) transcriptional profiles of genes associated with DH-CAP resistance in S. aureus; and (3) surface positive charges. Findings: MRSA strains isolated from human patients exhibited higher levels of resistance to all the three HD-CAPs than LAMRSA strains. Increase in HD-CAP resistance among human MRSA strains correlated with enhanced surface positive charge and increased expression of mprF, dltA and graRS genes. Conclusion & Significance: The results of this study suggested that endogenous exposure of MRSA to host specific HD-CAPs may play a role in adaptation and persistence of MRSA strains within their host.
Soo-Jin Yang has his expertise in bacterial pathogenesis and antibiotic resistant Staphylococcus aureus. He has been working on molecular mechanisms of antibiotic resistance and host defense antimicrobial peptide resistance in S. aureus. He has characterized major molecular pathways encompassing several twocomponent regulatory systems associated with resistance to antibiotics and HD-CAPS in S. aureus using both in vitro and in vivo models.