Wednesday, 31 May 2017

Newly-discovered gene that makes bacteria resistant to the most powerful antibiotics


A disturbing new gene that can make normal bacteria resistant to the strongest antibiotics has been detected in Canada, it had been revealed.

From The Independent:

The gene, MCR-1, is notable because it produces a chemical that makes bacteria resistant to colistin, a powerful antibiotic that has fallen out of favour due to its dangerous side effects, but one that is still used as a last-ditch medicine when all other remedies have failed.

The mobilized colistin resistance (mcr-1) gene confers plasmid-mediated resistance to colistin, one of a number of last-resort antibiotics for treating gram negative infections. mcr-1 is capable of horizontal transfer between different strains of a bacterial species and after discovery in November 2015 in E. coli (strain SHP45) from a pig in China it has been found in Escherichia coli, Salmonella enterica, Klebsiella pneumonia, Enterobacter aerogenes, and Enterobacter cloacae.As of 2017 it has been detected in more than 30 countries on 5 continents in less than a year.

If the newly-discovered gene were to make bacteria invincible to colistin, the sickest patients could find themselves in even more trouble.

As the Toronto Star reports, MCR-1 was first reported in British medical journal The Lancet in November last year, after Chinese scientists discovered a number of samples of the E-coli bacteria containing the MCR-1 gene on meat and hospital patients.

The noted that the gene likely originated in farm animals, due to the large amounts of antibiotics given to livestock in order to stop illness.

As the Star notes, MCR-1 has also been detected in bacteria samples gathered across the world, in Asia, Africa and even the UK.

Now, it has appeared in Canada, once in a patient in Ottowa and two in samples of ground beef sold in Ontario.


Posted by Dr. Tim Sandle