Toronto, Jan 28 : Scientists have discovered a new source of neurotoxin, known for its paradoxical ability to remove wrinkles yet cause an illness associated with food poisoning from a strain of animal gut bacteria, a finding that can potentially expand its therapeutic applications.
Clostridium botulinum toxin was able to jump into bacteria called Enterococcus faecium, through plasmids, mobile structures that contain DNA independently of the chromosomes and can be swapped from one bacterium to another, the study showed.
Enterococci are hardy microbes that thrive in the gastrointestinal tracts of nearly all land animals, including our own, and generally cause no harm.
But their ruggedness has lately made them leading causes of multi-drug resistant infections, especially in settings like hospitals where antibiotic use disrupts the natural balance of intestinal microbes.
"This is the first time that an active botulinum toxin has been identified outside of Clostridium botulinum and its relatives, which are often found in soil and untreated water," said Andrew Doxey, a bioinformatics professor at the University of Waterloo.
"Its discovery has implications in several fields, from monitoring the emergence of new pathogens to the development of new protein therapeutics -- it's a game changer," Doxey added.
Over the past 20 years, botulinum toxin type A, known as Botox, has been used for a growing number of therapeutic applications including treatment for migraines, leaky bladders, excessive sweating and cardiac conditions.
In the study, which appeared in the journal Cell Host and Microbe, the researchers were able to sequence the genome of the E.
faecium bacteria drawn from cow faeces, and found the gene for botulinum toxin in the bacterial strain.
They noted that the botulinum toxin was likely transferred from C. botulinum bacteria in the environment into the E. faecium bacteria in the cow's gut, showing that the toxin can be transferred between very different species.
"The botulinum toxin is a powerful and versatile protein therapeutic," said Michael Mansfield, a Biology doctoral student at the varsity.
"By finding more versions of the toxin in nature, we can potentially expand and optimise its therapeutic applications even further."