[ad_1]
Bacteria have a poor ability to grow quickly, which allows them to escape antibiotics in a short time. But now UC San Diego scientists have used evolution against them, “forming” bacteria-killing viruses to anticipate their next moves.
When life forms are exposed to stressful conditions, some individuals will survive better than others, thanks to random genetic mutations that confer useful traits. Over time, these traits will eventually spread through a population until they become the norm. It’s evolution at work, and it’s usually a wonderful process for helping life persist in the face of adversity – but there are actually times when we prefer to ground ourselves in adversity.
Bacteria are among nature’s most prolific evolutions, able not only to pass useful genes to the next generation, but also to trade them like trading cards within a current generation. So when faced with the harsh environment of antibiotics, it is no wonder that they managed to pull themselves out of danger within a few decades.
As our best drugs start to fail, bacteria are fast becoming one of the most pressing public health issues in the near future. Scientists are therefore increasingly turning to a long-ignored alternative – phage treatment.
Bacteriophages (or simply phages) are viruses that specifically attack bacteria, and although they were one of the first subjects of study in the treatment of bacterial infections, the development of antibiotics quickly led to the medical science in another direction. But now, with this path that seems to reach a dead end, phages look promising once again.
UC San Diego
In the new study, researchers set out to train phages to be better bacteria killers. The phages were grown in flasks alongside their target bacteria for 28 days, so they co-evolve and essentially learn the evolutionary escape routes the bacteria might try to use.
Then, these entrained phages were released onto other populations of bacteria. And of course, they were much better equipped to kill targets, killing bacteria about 1,000 more efficiently than untrained phages. The effects also lasted between three and eight times longer.
“The trained phage had already experimented with ways the bacteria tried to dodge it,” said Justin Meyer, lead author of the study. “He had ‘learned’ in a genetic sense. He had already developed mutations to help him counter the movements the bacteria were taking. We use the phage’s own improvement algorithm, evolution by natural selection, to regain its therapeutic potential and solve the problem of bacteria developing resistance to another therapy.
UC San Diego
The study adds additional evidence to support the use of phage therapy to treat bacterial infections. A few years ago, a phage treatment was given to a human patient with a dangerous infection for the first time, which could have saved his life. And they don’t even necessarily need to kill the bacteria to function – other studies have shown that they might just distract the bugs and make antibiotics effective again.
The research was published in the journal Proceedings of the National Academy of Sciences.
Source: UC San Diego
[ad_2]
Pictures Credit