Chlorogenic acid, a natural aromatic compound found in many plant species including coffee, may become a new class of antibiotic following a study that has unravelled the biochemistry and structural mechanism of its antibacterial property1.

The antioxidant and antibacterial properties of chlorogenic acid have been reported earlier but its mode of action remained elusive. Now a team led by Pravindra Kumar at the Biotechnology Department of at the Indian Institute of Technology, Roorkee, has the answer.

Using next-gen x-ray crystallography techniques they looked deep into the various metabolic pathways in a soil bacteria and found that this compound binds to an enzyme (chorismate mutase) in the "Shikimate Pathway", which is responsible for the synthesis of aromatic amino acids needed for the survival of a bacteria.

The authors say the "structural blueprints" obtained from their study can be used to tweak the chemical structure of cholorogenic acid to design a new class of plant-derived antimicrobials. Such antimicrobials target bacteria by inhibiting the enzymes in the "Shikimate Pathway". Because this metabolic pathway is present only in bacteria – and not in humans or animals – the antibiotic would specifically inhibit the growth of bacteria.