This is Scientific Americans 60 Second Science. I'm Karen Hopkins. This will just take a minute.

Tis the season for infections. And if you wind up with a prescription for penicillin or or its relatives, you're getting a gift that'll give those unwelcome bacteria a double whammy.

Because a new study shows that the penicillins wipe out infections by delivering a lethal one-two punch.

The findings are revealed in the journal

Cell. Scientists have long known that Penicillin and its relatives disrupt the

assembly of the bacterial cell wall, a tightly woven mesh made of peptide

studded sugars called peptidoglycans.

The drugs bind to enzymes that produce peptidoglycans and then link them together.

That interaction shuts down the enzyme's cross-linking capabilities.

Without the cross-links, the cell wall collapses and the

bursting bacteria die. But the full effect of the antibiotic, in widespread use since

World War II, was not appreciated till now. In the new study, researchers treated bacteria with a form of panicillin

and then watched what happened to the cell wall components.

As expected, the drug blocked cross-link formation.

But the surprise was that the enzyme that can no longer

forge links doesn't just sit there. It continues to churn out unlinked peptidoglycans, which

the bacteria don't want piling up, so they rapidly degrade. This futile cycle of synthesis and

destruction depletes bacterial resources speeding the path to

to...

The finding could point the way toward the development of new antibiotics,

ones that are similarly multi-talented when it comes to wiping out what ails you.

Thanks for the minute.

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