I fail to see how this invalidates any evidence for evolution. Evolution is an observed fact, the exact mechanism remains in question, and no reason it couldn’t be how The Creator set things up, but the fact that these genes existed does nothing to change the evolutionary evidence of change in populations to produce anti-biotic resistant bacteria.
>Evolution is an observed fact
Micro-evolution (birds turning into different birds that don’t interbreed), yes.
Macro-evolution (lizards turning into birds), no.
Genesis and evolution contradict each other. I suggest you read many articles at answersingenesis.org, and reconsider your opinion.
“I fail to see how this invalidates any evidence for evolution.”
What you might have missed is that evolution apologists have cited the appearance of antibiotic-resistant bacteria as an example of recently witnessed evolution in action. This discovery proves that bacteria did not develop this trait recently, so it invalidates that argument.