3 ms·
MRSA is due to the mecA gene, which is integrated into the S. Aureus genome. It's not plasmid-mediated resistance, which means that it's less likely to disappe
by timr 12y ago
MRSA is due to the mecA gene, which is integrated into the S. Aureus genome. It's not plasmid-mediated resistance, which means that it's less likely to disappear from bacterial populations, even in the absence of selective pressure:
http://www.eurekaselect.com/68849/article http://www.eurekaselect.com/68849/article
- Fomite 12y agoTrue - but the post I was responding to wasn't talking about plasmid-mediated resistance, but rather a broad assertion that a competitive disadvantage will take care of things. That's a strong assumption for which we have a counter example.
- deleted 12y ago[deleted]
- hga 12y agoMore than mecA, which itself doesn't sound like it's grossly maladaptive in the absence of β-Lactam antibiotics (it codes for an "replacement" enzyme that's not β-Lactam sensitive): https://en.wikipedia.org/wiki/Methicillin-resistant_Staphylococcus_aureus#mecA https://en.wikipedia.org/wiki/Methicillin-resistant_Staphylo... There's also regulatory genes that may be present, there are 6 known varieties of the whole gene cassette, with 5 further subtypes based on these regulators, so in the absence of β-Lactam antibiotics it sounds like a lot of them will be fit. Nasty.