City scientists build heat engines from bacteria

Can the omnipresent bacteria work for us or run nano machines? Yes, say scientists from Bengaluru, who built the world’s first micro heat engine using a bacterial colony. The micro heat engine does not follow the 200-year-old principles of regular heat engines based on which every automobile, locomotive or aircraft engine works. But they have the potential to unravel the mystery behind biological motors responsible for limb movement.

From the first manufactured automobile, the Ford Model T, to a contemporary family sedan, the basic working principle of the heat engine has remained unchanged since it was first laid down by French Engineer Sadi Carnot in 1824.

At nano scale
“The principles of heat engine didn’t change in the last 200 years. For the first time we have demonstrated a new way of heat engine functioning using bacteria. Such microscopic heat engines in future can power micro-scale or nano-scale electro-mechanical devices,” team leader Ajay Sood, professor of physics at the Indian Institute of Science (IISc), Bangalore, told DH.

An interdisciplinary group of scientists comprising researchers from IISc’s physics and molecular biophysics units and Jawaharlal Nehru Centre for Advance Scientific Research carried out a series of high-precision experiments to show how micro heat engine works.

“Unlike the regular engines that work with less than 10% efficiency, the micro heat engine has 50% efficiency. A large number of futuristic applications can be thought of. The discovery may also lead to better understanding of biological motors,” said Sood. The findings have been reported in the August 29 issue of Nature Physics.