vanA

gene

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Last updated

July 23, 2026

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The vanA gene is a genetic element that confers resistance to vancomycin, an antibiotic used to treat serious infections caused by gram-positive bacteria. This gene is suspected to be acquired by Staphylococcus aureus (MRSA) from vancomycin-resistant enterococci (VRE). The vanA gene alters the peptide target that vancomycin normally binds to, thereby inhibiting the antibiotic's ability to disrupt bacterial cell wall synthesis. This resistance mechanism is a significant concern in healthcare settings, as it can lead to infections that are very difficult to treat. Vancomycin itself is derived from an actinomycete and is effective against gram-positive bacteria, particularly those resistant to methicillin.12

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MRSA
Mechanisms of resistance
…acquire a gene known as vanA from VRE. VanA alters the peptide target that vancomycin and closely related antibiotics (e.g., teicoplanin) normally bind to in order to inhibit bacterial cell wall synthesis. In the presence of vancomycin, MRSA may also be able to rapidly effect genetic mutations that alter cell…
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…acquire a gene known as vanA from VRE. VanA alters the peptide target that vancomycin and closely related antibiotics (e.g., teicoplanin) normally bind to in order to inhibit bacterial cell wall synthesis. In the presence of vancomycin, MRSA may also be able to rapidly effect genetic mutations that alter cell…
Read More