When bacteria sneak into your body, it's the immune system that notices something is amiss.
New research by an Australian team spanning three universities has discovered one of the ways the immune system recognises pathogens is by finding the building blocks to vitamins the bacteria has been producing.
Yes, bacteria produces its own vitamins.
As professor Jim McCluskey told The Huffington Post Australia, the vitamins made by bacteria have nothing to do with the vitamins we eat.
"We're mammals so we get our vitamins through our diet, but generally for bacteria, there aren't enough free vitamins to sustain them so they produce their own," McCluskey told HuffPost Australia.
He said T-cells in our body -- the cells that look for abnormalities -- were able to find the scraps of this vitamin production, and it led them to the bacteria.
This research has won the $80,000 GSK Award For Research Excellence at the Research Australia Annual Awards in Melbourne on Wednesday night.
McCluskey said the discovery was a group effort between The University of Melbourne, Monash University and other collaborators.
"It was really a team of people engaging in hypotheses-driven science, using our curiosity to lead to this breakthrough," McCluskey said.
"We are at the tip of the iceberg in understanding and over the next 10 years we hope to learn more."
The research could lead to new ways of treating conditions like inflammatory bowel disease, peptic ulcers, tuberculosis and salmonella poisoning.
Professor Jamie Rossjohn said T-cells were a fascinating area of research.
"Our research is part of a wider program looking at how T-cells recognise unusual molecules that are foreign and therefore signals of some sort of micro invasion," Rossjohn said.
"It helps our understanding of immunity."