Penicillin, it was one of the great feats of science and has saved countless lives. Antibiotics have been fighting the war on infections since before most of us were even alive. But since the 1960’s they have been fighting a losing battle, with the rise of new ‘super’ bugs penicillin and friends just doesn’t seem to cut it.
With so many researchers scrambling to find new and improved antibiotics it is a surprising but novel idea– is there a way to recycle the old ones? Enter Chuanbing Tang, one of the lead researchers at the University of South Carolina with an effort to breathe new life into the penicillin family.
Beta-lactam, the thing that makes penicillin so powerful drastically reduces bacterias ability to reproduce by cell division. Unfortunately, bugs like MRSA have developed the ability to produce something called beta-lactamase, an enzyme [a protein that breaks something down] which destroys the beta-lactam before it can do it’s job.
[Loony bonus hint: anytime you see a -ase at the end, chances are it is an enzyme that deals with whatever comes before it.]
Which is just a fancy way to say that things like penicillin are knocked out for the count, losing the fight before it even has a chance to try. The worst part is that it is such a broad attack strategy it is hard to defend against.
Typically researchers look for ways to hide the beta-lactam with other molecules [sort of like putting on clothes to 'hide' from the cold], this is why you see so many things that sound like penicillin, they are from the same family structurally.The goal with the research being done however, is to find a way to keep beta-lactamase at bay.
“Instead of developing new antibiotics, here we ask the question, ‘can we recycle the old antibiotics?” said Tang. “With traditional antibiotics like penicillin G, amoxicillin, ampicillin and so on, can we give them new life?”
How do they plan on doing it? The researchers have created a protective polymer, a joint collaboration which was developed in Tang’s chemistry laboratory. In the lab tests, the coating has shown to drastically decrease the effectiveness of beta-lactamase.
The study showed the effectiveness of the new polymer on four different types of beta-lactams. The polymer alone even demonstrated antimicrobial properties, breaking down the bacterial cells while leaving human red blood cells unaffected. By a variety of measures, the polymer was found to be nontoxic to human cells in laboratory tests.
So when can we expect to see Penicillin 2.0? Not for some time unfortunately, but Tang and his team are pushing hard to make this happen as soon as possible.
Already know your helicases from your -ase’s? You probably want the full article, which you can find — here!
Zhang J., Chen Y.P., Miller K.P., Ganewatta M.S., Bam M., Yan Y., Nagarkatti M., Decho A.W. & Tang C. (2014). Antimicrobial Metallopolymers and Their Bioconjugates with Conventional Antibiotics against Multidrug-Resistant Bacteria, Journal of the American Chemical Society, 136 (13) 4873-4876. DOI: 10.1021/ja5011338