The human intestinal tract – a hotbed of resistance gene transfer? Part II1

Although bacteria can become resistant to antibiotics by mutation, a far quicker and easier way for them to achieve the same goal is to acquire pre-formed resistance genes from other bacteria. It is well established that such transfers across species and genus lines occur under laboratory conditions, but the important practical question is whether such transfers actually occur in situ and, if so, whether they occur rarely or frequently. Part II of this article summarizes the evidence that antibiotic resistance genes are, in fact, being transferred among bacteria in the colon and then goes on to explore how and why investigators are trying to determine what conjugative elements mediate this transfer.