Scientists Discover Antibiotic Mechanism

NIH | APRIL 22, 2015

The widespread use of antibiotics in modern society has led to a sharp rise in antibiotic-resistant bacteria. As a result, much research has focused on creating new compounds to fight these bacteria.

Antibiotics.Photo: Kristoferb/Wikimedia Commons (CC-BY-SA-3.0)

Borrelidin was isolated from the bacteria Streptomyces about 50 years ago. The compound has broad antibacterial, antifungal, antimalarial, anticancer, insecticidal, and herbicidal activities. It works by interfering with a type of essential enzyme called tRNA synthetase. These enzymes help cells make proteins through a process called translation.

A research team led by Dr. Min Guo of the Scripps Research Institute investigated how borrelidin interferes with threonyl-tRNA synthetase. They used a technique called X-ray crystallography to decipher the structure of the enzyme when borrelidin interacts with it.

The researchers found that borrelidin simultaneously occupies the enzyme binding sites for the amino acid L-threonine, molecule tRNA, and energy molecule ATP. Thus, the compound blocks all 3 molecules from the synthetase’s active site. As a result, L-threonine can’t be linked to its tRNA, and protein translation fails.

The researchers determined that borrelidin binding also causes a change to the structure of the enzyme that creates a fourth spot for borrelidin attachment. Borrelidin inhibits translation by binding to 4 sites that are necessary for threonyl-tRNA synthetase to function.

Researchers have been investigating the potential of tRNA synthetase inhibitors to fight bacteria, fungi, cancers, and autoimmune diseases. The insights from this research may help guide scientists in the rational design of improved, more selective drugs.

YOU MAY ALSO LIKE

Slim people have a genetic advantage when it comes to maintaining their weight

In the largest study of its kind to date, Cambridge researchers have looked at why some people manage to stay thin while others gain weight easily. They have found that the genetic dice are loaded in favour of thin people and against those at the obese end of the spectrum.

Asteroid Tracking Network Observes Close Approach

On Oct. 12 EDT a small asteroid designated 2012 TC4 will safely pass by Earth at a distance of approximately 26,000 miles (42,000 kilometers). This is a little over one tenth the distance to the Moon and just above the orbital altitude of communications satellites.

Bacteria Used to Create Fertilizer Out of Thin Air

A research aimed at engineering plants to make them able to create their own fertilizer in the future.

Bone-Like Particles Found Travelling through Human Bloodstream

Researchers have discovered that blood vessels within bone marrow may progressively turn into bones with advancing age and run around the bloodstream.

Size matters: if you are a bubble of volcanic gas

A team of scientists, including a volcanologist and mathematician from the University of Cambridge, discovered the phenomenon through detailed observations of gas emissions from Kīlauea volcano in Hawaii.

Study reveals attention training improves intelligence and brain function of children

Attention training improves intelligence and brain function of children. The benefit is greater if the training is guided by an educator, according to recent research conducted at the University of Granada.