Community-Associated MRSA Infection in Remote Amazon Basin Area, Peru.
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ABSTRACT:
SUBMITTER: Garcia C
PROVIDER: S-EPMC4861527 | biostudies-literature | 2016 May
REPOSITORIES: biostudies-literature
Publications
Community-Associated MRSA Infection in Remote Amazon Basin Area, Peru.
García Coralith C Astocondor Lizeth L Reyes Jinnethe J Carvajal Lina P LP Arias Cesar A CA Seas Carlos C
Emerging infectious diseases 20160501 5
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Project description:Panton-valentine leukocidin (PVL) has been linked to worldwide emergence of community-associated methicillin resistant Staphylococcus aureus (CA-MRSA) -- its role in virulence in unclear. Here we show that PVL had no effect on global gene expression of prominent CA-MRSA strains nor did it affect bacterial clearance from lungs, spleen and kidneys in a highly discriminatory rabbit bacteremia model. These findings negate a large body of epidemiological research that implicated PVL in CA-MRSA virulence. Keywords: mutant vs wild type in 2 different growth phases grown in 2 different medias
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2010-06-19 | E-GEOD-8677 | biostudies-arrayexpress
Project description:The success of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) as pathogens is due to a combination of antibiotic resistance with high virulence. However, evolution of the exceptional virulence potential of CA-MRSA is not understood. Our previous study indicated that differential gene expression contributes substantially to this process. Thus, we here investigated the role of the pivotal virulence gene regulatory system agr in the most prevalent CA-MRSA strain USA300. Using a mouse subcutaneous infection model, we show that agr is essential for the development of CA-MRSA skin infections, the most frequent manifestation of disease caused by CA-MRSA. Furthermore, genome-wide analysis of gene expression revealed significant differences in agr-dependent virulence gene regulation between CA-MRSA, HA-MRSA, and laboratory strains. Our findings demonstrate that agr functionality is critical for CA-MRSA disease and indicate that an adaptation of the agr regulon to optimize expression of a broad set of virulence determinants may have contributed to the evolution of exceptionally pronounced virulence of CA-MRSA strains. Keywords: wild type vs mutant
2011-03-29 | GSE18793 | GEO
Project description:The success of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) as pathogens is due to a combination of antibiotic resistance with high virulence. However, evolution of the exceptional virulence potential of CA-MRSA is not understood. Our previous study indicated that differential gene expression contributes substantially to this process. Thus, we here investigated the role of the pivotal virulence gene regulatory system agr in the most prevalent CA-MRSA strain USA300. Using a mouse subcutaneous infection model, we show that agr is essential for the development of CA-MRSA skin infections, the most frequent manifestation of disease caused by CA-MRSA. Furthermore, genome-wide analysis of gene expression revealed significant differences in agr-dependent virulence gene regulation between CA-MRSA, HA-MRSA, and laboratory strains. Our findings demonstrate that agr functionality is critical for CA-MRSA disease and indicate that an adaptation of the agr regulon to optimize expression of a broad set of virulence determinants may have contributed to the evolution of exceptionally pronounced virulence of CA-MRSA strains. Keywords: wild type vs mutant Wild type vs mutant agr strains.
2011-03-29 | E-GEOD-18793 | biostudies-arrayexpress