Polymedix -vs- Tetraphase

Post from Falconer66a:

They (Tetraphase's compounds) are tetracycline-based. Their difference is that the company is able to synthesize new forms of tetracycline antibiotics that do not appear in nature.

That’s all well and good. There would be a very good chance that the company can come up with novel tetracyclines that would prove more effective than the older, existing ones.

But in comparison to PolyMedix’s antimicrobials, there’s one gigantic difference. Any tetracycline antibiotic, whether extracted from soil bacteria and purified (as with the original tetracycline), or if an existing tetracycline is chemically modified, or in the case of the novel, entirely synthesized tetracyclines of this company, they all have to get themselves inside the target bacterium, and must remain in there to work their bacterially lethal magic. That’s the problem. Sooner or later, pathogenic bacteria will evolve mechanisms to either keep out the new antibiotic, or will hike the active rejection and expelling of the molecules once they get inside the cell. Either way, the bacterial cells and their pathogenicity survive.

Not so, though, with PolyMedix molecules. They need merely bump up against the target bacterium and its plasma membrane is almost instantly disrupted. The cell’s chemical guts spill out, and the pathogenic game is over.