Actinobacteria

Researchers from the Vellore Institute of Technology (VIT), Tamil Nadu, have made a significant discovery while studying the Rajgir hot spring lake in the Nalanda district of Bihar — a site where people traditionally take holy baths, believing the water can cure various ailments.

Using 16S rRNA metagenomics, the team analyzed the microbial composition of the hot spring and uncovered a diverse community of bacteria. Notably, Actinobacteria accounted for 40–43% of the microbial diversity. This group of bacteria is historically significant as it includes species that produce well-known antibiotics like streptomycin and tetracycline.

The team focused on isolating specific antibacterial compounds produced by these microbes. Among the bacteria identified were thermophiles — organisms that thrive in high temperatures, ranging from 45°C to 70°C — extreme conditions that can cause third-degree burns in humans.

In the context of rising antimicrobial resistance (AMR), the search for new antibiotics has become more urgent. The indiscriminate use of antibiotics has rendered many pathogens resistant, creating a silent global health crisis.

The VIT team’s most notable discovery was the compound diethyl phthalate, which was found to inhibit the growth of Listeria monocytogenes — the bacterium responsible for listeriosis, a potentially fatal foodborne illness. This opens up the possibility of developing diethyl phthalate as a novel drug to treat infections caused by L. monocytogenes.