Mapping the cancer genome wilderness

A huge cancer genome project has highlighted how DNA that doesn’t code for proteins is still important for keeping our cells on Read more

Stem-like CD8 T cells stay in lymph nodes/spleen

Virus-specific CD8 T cells accumulate in lymph nodes and in other organs, without circulating in abundance in the Read more

To fight cancer, mix harmless reovirus with 'red devil'

The GDBBS symposium included a talk about the next step: attaching the souped-up reovirus to Read more

MCR-1

Retaining the resistance: MCR-1, colistin + lysozyme

If you’ve been following the news about antibiotic resistant bacteria, you may have heard about a particularly alarming plasmid: MCR-1. A plasmid is a circle of DNA that is relatively small and mobile – an easy way for genetic information to spread between bacteria. MCR-1 raises concern because it provides bacteria resistance against the last-resort antibiotic colistin. The CDC reports MCR-1 was found in both patients and livestock in the United States this summer.
David Weiss, director of Emory’s Antibiotic Resistance Center, and colleagues have a short letter in The Lancet Infectious Diseases showing that MCR-1 also confers resistance to an antimicrobial enzyme produced by our bodies called lysozyme. MCR-1-containing strains were 5 to 20 times less susceptible to lysozyme, they report.
This suggests that the pressure of fighting the host immune system may select for MCR-1 to stick around, even in the absence of colistin use, the authors say.
While the findings are straightforward in bacterial culture, Weiss cautions that there is not yet evidence showing that this mechanism occurs in live hosts. For those that really want to get alarmed, he also calls attention to a recent Nature Microbiology paper describing a hybrid plasmid with both MCR-1 and resistance to carbapenem, another antibiotic.

Read more

Posted on by Quinn Eastman in Uncategorized Leave a comment