Bacterial Intelligence? sensing molecules for food (General)

by David Turell , Friday, August 03, 2018, 21:26 (2302 days ago) @ David Turell

Scientists have worked out the molecular machine that senses food for bacteria:

https://phys.org/news/2018-08-hungry-bacteria-nutrients-environment.html

"The research team, led by Dr. Helen O'Hare from the University of Leicester's 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.

"'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."

"The team was able to work out which proteins helped bacteria sense nutrients by deleting specific genes for signaling proteins from a bacterial genome. With the genes removed, they found that this disrupted the ability of the bacteria to sense nutrients, confirming the function of the genes.

"Using X-ray crystallography at the Diamond Light Source at Harwell, they were then able to determine the structure of the sensor protein and predict which other bacteria may sense amino acids in the same way."

Comment: Once again we see that bacteria use purposeful molecular reactions to react to stimuli. These are automatic mechanisms that use enzymes, giant molecules to activate and control the response speedily.