Journal of medical microbiology
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Fatty acid modifying enzyme (FAME) is an extracellular enzyme that inactivates bactericidal fatty acids by esterifying them to cholesterol. Inactivation of these fatty acids may allow Staphylococcus epidermidis to live for long periods of time on the skin. This study describes the identification and partial characterisation of an extracellular activator of FAME production. ⋯ Treatment of the activator with proteinase K did not destroy its ability to induce FAME expression. Addition of S. aureus activator to S. epidermidis cultures also increased FAME expression. However, when S. epidermidis activator was added to S. aureus cultures no increase or inhibition in FAME production was observed.
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The use of DNA amplification techniques such as the polymerase chain reaction (PCR) in modern diagnostic microbiology not only allows the sensitive and specific identification of micro-organisms but also the detection of specific antibiotic resistance genes. This study describes a multiplex PCR on bacterial colonies picked directly from agar plates without preceding DNA preparation. Eubacteria and staphylococci were identified by, 16S rRNA specific PCR products. ⋯ The coa gene was detected only in S. aureus (488) strains with a specificity of 100%, and was not detected in any of the coagulase-negative staphylococci (198). The mecA gene was detected in 98% of methicillin-resistant staphylococci (393) and in 2% of all methicillin-susceptible staphylococci (293). The multiplex PCR with co-amplification of different determinants provides rapid reliable information on staphylococcal identification and methicillin susceptibility supporting the diagnosis, treatment and control of staphylococcal infections.