If Sisyphus was a microbiologist...

As a microbiologist studying pathogenic bacteria, I'm all too aware of the cyclical arms race we are currently trapped in. For every novel antibiotic we produce, the microbes inevitably evolve mechanisms to degrade them, rendering them useless. Every time we seem reach the top of the hill (methicillin) the boulder slips down the other side (MRSA). We fight the good fight in the hopes that we can keep them on their toes until the day comes when we find our ever-ellusive magic bullet. Then the microbes sucker-punch us. It appears that they are no longer content to simply neutralize our weapons, but now feel to need to make us look silly in the process: by feeding on the very compounds we are trying to kill them with, no less.
Now, where the hell did my boulder go?
To be fair, the offending bacteria live in the soil and are not typically the targets of man-made antibiotics; but if the soil microbes can evolve these mechanisms, so can the pathogens...