Animal-friendly herbicide in development

Scientists at Monash University are researching an environmentally friendly alternative to herbicides that targets weeds but does not affect animals. This research could also lead to new treatments for the internationally alarming health issue of tuberculosis infection.

The development stems from the process of an enzyme pathway " called the pantothenate pathway " that only occurs in plants, fungi and micro-organisms but not animals. Micro-organisms and plants synthesize pantothenate (Vitamin B5) via this process, while animals obtain this essential nutrient only from their diet.

"As the pantothenate pathway is not present in animals it represents an exciting target for the development of novel herbicides," said Dr Kellie Tuck, who is leading the research with Professor Chris Abell from the University of Cambridge.

Dr Tuck said their focus is on developing compounds that block the final step in the enzyme pathway " an enzyme called pantothenate synthetase. This enzyme is vital if plants are to produce Vitamin B5, without which they die.

The chemical structure of pantothenate synthetase is already known. Scientists are now devising and synthesising molecules that bind to this structure and stop the enzyme from properly functioning.

"Blocking the pathway is also a potential treatment for tuberculosis because pantothenate biosynthesis is essential for the virulence of Mycobacterium tuberculosis, the organism that causes tuberculosis."

Tuberculosis is responsible for up to three million deaths worldwide each year, more than any other infectious disease. It is becoming a global health threat due to the emergence of multi-drug resistant strains of the bacterium.

Dr Tuck said a number of potential enzyme blockers had been synthesised and were now being assessed for their effectiveness in shutting down the enzyme pathway.