Latest News

Clues beginning to emerge on asymtomatic SARS-CoV-2 infection
Back in November of 2020, during the first wave of the COVID-19 pandemic, I was teaching an in-person microbiology laboratory. One of my students had just been home to see his parents, and they all c…
Read more
Could there maybe be better uses of genetics and probiotics?
Professor Meng Dong and his laboratory have created a probiotic that can metabolize alcohol quickly and maybe prevent some of the adverse effects of alcohol consumption. The scientists cloned a highl…
Read more
ChatGPT is not the end of essays in education
The takeover of AI is upon us! AI can now take all our jobs, is the click-bait premise you hear from the news. While I cannot predict the future, I am dubious that AI will play such a dubious role in…
Read more
Fighting infections with infections
Multi-drug-resistant bacterial infections are becoming more of an issue, with 1.2 million people dying of previously treatable bacterial infections. Scientists are frantically searching for new metho…
Read more
A tale of two colleges
COVID-19 at the University of Wisconsin this fall has been pretty much a non-issue. While we are wearing masks, full in-person teaching is happening on campus. Bars, restaurants, and all other busine…
Read more

News

The stringent response can influence antibiotic resistance


 

Cancer is a horrible disease, killing over half a million people in the United States every year and is the leading, or second cause of death in most states. It is especially horrific when it affects children. Great strides have been made in cancer therapy in children, increasing rates of 5 year survival for some cancers above 80%. Some treatments, especially when treating leukemia, require the killing of all white blood cells, which can leave the patient open to infection. Work by Honsa et al. describes the persistent infection of a 6-week-old infant with vancomycin-resistant enterococcus (VRE). Even with appropriate treatment against the infection the VRE was able to survive. The infection was eventually cleared when the patients immune system came back online 26 days later.

Curious how VRE survived treatment that was demonstrated to be able to kill it, the scientists sequenced 22 isolates obtained from the patient over the course of the infection. A single mutation in the relA gene was discovered that induced the stringent response. This response is normally turned on when the microbe is experiencing stress, such as starvation. The mutant was still susceptible to linezolid and daptomycin when in the test tube, and when growing individually, but and it had increased resistance to these antibiotics when growing in a biofilm. The addition of a compound that disrupts biofilm formation, caused the microbe to again be susceptible to the antibiotics.

The work demonstrates a new method of approach to treat persistent infections and also indicates the stress response in resisting antibiotics. It also shows the importance of our immune systems in fighting infections, even when treated with antibiotics.