Skip to comments.Study: Unique Combination of Antibiotics Kills Methicillin-Resistant Staphylococcus aureus
Posted on 04/30/2014 10:11:51 PM PDT by neverdem
According to new research published this week in the journal Nature, an acyldepsipeptide antibiotic called ADEP in combination with the bactericidal antibiotic drug rifampicin eliminates the methicillin resistant Staphylococcus aureus.
Methicillin-resistant Staphylococcus aureus (MRSA) is a bacterium that is resistant to many antibiotics. It is responsible for several chronic infections such as osteomyelitis, endocarditis, or infections of implanted medical devices. These infections are often incurable, even when appropriate antibiotics are used.
Senior author of the study, Prof Kim Lewis of Northeastern University, suspected that a different adaptive function of bacteria might be the true culprit in making these infections so devastating.
The study represents the culmination of more than a decade of research on a specialized class of cells produced by all pathogens called persisters.
These cells evolved to survive. Survival is their only function. They dont do anything else, Prof Lewis said.
Prof Lewis and his colleagues posited that if they could kill these expert survivors, perhaps they could cure chronic infections.
They have found that persisters achieve their singular goal by entering a dormant state that makes them impervious to traditional antibiotics. Since these drugs work by targeting active cellular functions, they are useless against dormant persisters, which arent active at all. For this reason, persisters are critical to the success of chronic infections and biofilms, because as soon as a treatment runs its course, their reawakening allows for the infection to establish itself anew.
A recent study found that a drug called ADEP effectively wakes up the dormant cells and then initiates a self-destruct mechanism.
Coupling ADEP with rifampicin, allowed the team to completely destroy...
(Excerpt) Read more at sci-news.com ...
Good news. Wake them up. Wake them all up. Then kill them dead!!!!
This is huge, but evolution does not take a back seat. If just one bacterium survives the onslaught, the cycle will start all over.
"Staphylococcus aureus produces hospital- and community-acquired infections, with methicillin-resistant S. aureus posing a serious public health threat. The golden carotenoid pigment of S. aureus, staphyloxanthin, promotes resistance to reactive oxygen species and host neutrophil-based killing, and early enzymatic steps in staphyloxanthin production resemble those for cholesterol biosynthesis. We determined the crystal structures of S. aureus dehydrosqualene synthase (CrtM) at 1.58 angstrom resolution, finding structural similarity to human squalene synthase (SQS). We screened nine SQS inhibitors and determined the structures of three, bound to CrtM. One, previously tested for cholesterol-lowering activity in humans, blocked staphyloxanthin biosynthesis in vitro (median inhibitory concentration ∼100 nM), resulting in colorless bacteria with increased susceptibility to killing by human blood and to innate immune clearance in a mouse infection model. This finding represents proof of principle for a virulence factorbased therapy against S. aureus."
Except vote for Democrats.