How hungry bacteria sense nutrients in their environment
Researchers have shed new light on how bacteria sense nutrients in their environment - which could provide important knowledge in the development of drugs and antibiotics to combat a range of diseases including tuberculosis.
The research team, led by Dr Helen O’Hare from our Department of Infection, Immunity and Inflammation, has identified functions of a specific protein (Kinase G) that allow groups of bacteria such as Mycobacterium tuberculosis to detect amino acids in their surroundings, allowing the bacteria to regulate their metabolism in response to the available nutrients.
This protein is found in a large and important group of bacteria that includes the causative agent of tuberculosis in humans, as well as bacteria important for food and antibiotic production. The research identified the types of nutrients that can be sensed (aspartate and glutamate) as well as the sensor protein that recognises the nutrients.
This understanding of how bacteria detect and respond to amino acids in their local environment provides useful information to scientists in terms of understanding how bacteria function and how drugs could target specific proteins.
“Serine threonine protein kinases are found in all organisms, from humans to bacteria, but they are less well understood in bacteria,” says Dr O’Hare. “The findings represent one of the first instances in bacteria where it has been possible to identify the stimuli that trigger signaling.
“A bacterial pathogen can ‘taste’ the same amino acids that humans can. The sensor has a similar structure to human glutamate receptors but the way the information is transmitted into the bacterial cell is different and involves a different set of proteins, unlike signaling systems that have been studied previously. The research brings understanding about how a pathogen can sense the nutrients in its niches in the human body, but also broad understanding of how non-pathogenic bacteria sense their surroundings.”