It might also power future generations of nano devices and materials, according to biological engineer Danielle Cook France and colleagues at MIT, the Whitehead Institute, the Marine Biological Laboratory, and the University of Illinois, Chicago. France presented her findings Sunday at the 45th Annual Meeting of the American Society for Cell Biology in San Francisco.
The spring in the unicellular Vorticella is a contractile fiber bundle, called the spasmoneme, which runs the length of the stalk. At rest, the stalk is elongated like a stretched telephone cord. When it contracts, the spasmoneme winds back in a flash, forming a tight coil. To find out how fast and how hard Vorticella recoils, France and colleagues used modern microscopes and tools to measure the force and speed of the spring. This is one powerful engine, France reports. The spasmoneme's contraction is measured in nano-newtons of force and centimeters/second of speed in a biological world where the ruler markings are usually in tiny pico-newtons and micrometers/second. Gram for gram, the power of the spasmoneme engine outperforms human muscles and car engines.
It also runs on a different fuel. Molecular motors that power muscle contraction, for example, use ATP molecules for energy. The spasmoneme runs on calcium, but its drive mechanism was poorly understood until France and colleagues got under the nano hood. Like van Leeuwenhoek, the researchers studied Vorticella under the microscope but they also had specialized biochemical