Scientists Uncover Survival Strategies of Primitive Organisms Using Toxin-Antitoxin Systems

24th December 2024, New Delhi: Scientists have revealed critical insights into the survival strategies of some of Earth’s oldest organisms, shedding light on how archaea, ancient heat-loving microorganisms, cope with extreme environmental conditions. The research, conducted by Dr. Abhrajyoti Ghosh and his team at the Department of Biological Sciences at Bose Institute, explores the role of toxin-antitoxin (TA) systems in enabling these organisms to survive in high-temperature environments.

Archaea, one of the earliest forms of life on Earth, thrive in some of the most hostile environments, such as hot volcanic pools. As the planet’s climate continues to change, understanding how these organisms adapt to extreme heat has become crucial. The study published in mBio, a journal of the American Society for Microbiology, specifically examines the TA system in Sulfolobus acidocaldarius, a heat-loving archaeon found in volcanic regions like Barren Island in the Andaman and Nicobar Islands.

TA systems, which are present in both archaea and bacteria, help these microorganisms survive under stress. In this study, Dr. Ghosh’s team focused on the VapBC4 TA system, discovering that it plays a key role in helping S. acidocaldarius endure heat stress. When exposed to high temperatures, this system halts protein production, aiding in the formation of “persister cells.” These cells enter a dormant state, conserving energy and preventing the formation of damaged proteins. This survival tactic allows them to endure extreme conditions until the environment becomes more favorable.

The research reveals how the VapC4 toxin, once released after the breakdown of the VapB4 protein, blocks protein synthesis, effectively safeguarding the organism. This discovery offers new insights into how archaea use TA systems to survive harsh environments and provides valuable clues about microbial adaptation to extreme conditions, which is increasingly relevant in the face of global climate change.

This groundbreaking work enriches our understanding of the molecular survival mechanisms of ancient organisms and highlights the critical role of TA systems in evolutionary biology.