Unlocking the genetic secrets of wheat

Scientists at Swinburne University of Technology have discovered how wheat seedlings defend themselves against bacteria, opening the door for food and health applications.

Researchers in the Faculty of Science, Engineering and Technology have been exploring specific genes in wheat and their resistance to bacteria and fungi.

"Wheat is the staple food of 35 per cent of the world's population and the third largest cereal crop after maize and rice," Swinburne molecular biologist Professor Mrinal Bhave said.

"Finding how genes control grain quality can help us develop more robust wheat crops."

Puroindoline a and puroindoline b (Pina and Pinb) determine grain hardness. Peptides – short chains of protein building blocks – derived from these genes are known for their antimicrobial properties and are implanted in various crops.

How these peptides defend wheat seedlings from diseases was not known.

Swinburne PhD student Rebecca Alfred, under the guidance of Professor Bhave and microbiologist Professor Enzo Palombo, designed artificial peptides that mimic the ones found in grains and tested them against various bacteria, fungi and mammalian cells.

She found that the peptides were aggressive towards a range of bacteria and fungi, but left mammalian cells unharmed, so could be used in any area that aims to reduce microbial contamination, such as food safety, hygiene and surface decontamination.

The peptides also tolerate high heat and can be used as preservatives in food applications, such as milk or orange juice.

The team is now modifying these peptides and testing them against more bacteria and fungi.