Scientists have learned that bacteria that are vulnerable when floating around as individual cells in what is known as their “planktonic state” are much tougher to combat once they get established in a suitable place — whether the hull of a ship or inside the lungs — and come together in tightly bound biofilms. In that state, they can activate mechanisms like tiny pumps to expel antibiotics, share genes that confer protection against drugs, slow down their metabolism or become dormant, making them harder to kill.

The answer, say researchers, is to find substances that will break up biofilms.
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Melander said “a throwaway sentence in an obscure journal” — the Bulletin of the Chemical Society of Japan — gave them another clue. They isolated a compound from the sponge that disperses biofilms and figured out how to synthesize it quickly and cheaply.
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But dispersing biofilms without understanding all the ramifications could be a “double-edged sword,” Romeo warned, because some bacteria in a biofilm could wreak worse havoc once they disperse.

“Simply inducing biofilm dispersion without understanding exactly how it will impact the bacterium and host could be very dangerous, as it might lead to spread of a more damaging acute infection,” he said.