Researchers unlock cheesemaking secret—17 August 2017

Researchers on a collaborative ARC Linkage Project, co-funded by Dairy Innovation Australia Limited, say their new knowledge on the inner workings of a bacterium has important implications for Australia’s billion dollar cheese industry.

A discovery by The University of Queensland (UQ), Columbia University and University of Washington research group has explained the regulation of an enzyme in the bacterium Lactococcus, which is used as a starter culture in cheese production.

“Our research provides new insights into this industrially important food bacterium,” said ARC-funded UQ researcher, Associate Professor Mark Turner. “Australia produces more than a billion dollars’ worth of cheese each year, and Lactococcus is the most commonly used starter culture.”

Two UQ PhD students in Dr Turner’s food microbiology research laboratory, Thu Vu and Huong Pham, identified that the enzyme known as pyruvate carboxylase was essential for efficient milk acidification, an important industrial trait in Lactococcus starter cultures. The enzyme is essential for synthesising the amino acid aspartate, and bacteria defective in the enzyme were unable to produce high levels of lactic acid in milk, which is required for the first stage of cheese making. 

“Our collaboration also found that a recently discovered small molecule in bacteria, called cyclic-di-AMP, directly binds to and inhibits the pyruvate carboxylase enzyme”, said Associate Professor Turner. “The molecule is essential for growth in a wide range of bacteria, including many human pathogens, and we are only in the early stages of understanding how it controls important processes in bacteria.”

Media issued by The University of Queensland.

Image: Cheese 43 bg 060106.jpg.
Image credit: Wikipedia Commons.

Original Published Date: 
Thursday, August 17, 2017