Identification of a Botulinum Neurotoxin-like Toxin in a Commensal Strain of Enterococcus faecium.
Botulinum neurotoxins (BoNTs), produced by various Clostridium strains, are a family of potent bacterial toxins and potential bioterrorism agents. Here we report that an Enterococcus faecium strain isolated from cow feces carries a BoNT-like toxin, designated BoNT/En. It cleaves both VAMP2 and SNAP-25, proteins that mediate synaptic vesicle exocytosis in neurons, at sites distinct from known BoNT cleavage sites on these two proteins. Comparative genomic analysis determines that the E. faecium strain carrying BoNT/En is a commensal type and that the BoNT/En gene is located within a typical BoNT gene cluster on a 206 kb putatively conjugative plasmid. Although the host species targeted by BoNT/En remains to be determined, these findings establish an extended member of BoNTs and demonstrate the capability of E. faecium, a commensal organism ubiquitous in humans and animals and a leading cause of hospital-acquired multi-drug-resistant (MDR) infections, to horizontally acquire, and possibly disseminate, a unique BoNT gene cluster.
|Year of Publication
Cell Host Microbe
2018 Feb 14
|PubMed Central ID
F32 GM121005 / GM / NIGMS NIH HHS / United States
R01 NS080833 / NS / NINDS NIH HHS / United States
R01 AI132387 / AI / NIAID NIH HHS / United States
P30 HD018655 / HD / NICHD NIH HHS / United States
R01 AI108710 / AI / NIAID NIH HHS / United States
R01 AI072360 / AI / NIAID NIH HHS / United States
P30 DK034854 / DK / NIDDK NIH HHS / United States
P01 AI083214 / AI / NIAID NIH HHS / United States