Cell-based Nano Machine Breaks Record

Dec 22, 2005
Cell-based Nano Machine Breaks Record
Image: Vorticella cells with coils expanded. (Image captured using the LCPolScope, developed by Shinya Inoue at the Marine Biological Laboratory, Woods Hole, MA; image by Danielle France)

Researchers have known for some time that a long, fibrous coil grown by a single-cell protozoan is, gram for gram, more powerful than a car engine. Now, researchers at Whitehead Institute -- together with colleagues at MIT, Marine Biological Laboratory in Woods Hole, MA, and University of Illinois, Chicago -- have found that this coil is far stronger than previously thought. In addition, the researchers have discovered clues into the mechanism behind this microscopic powerhouse.

"These findings are twofold," says Danielle France, a graduate student in the lab of Whitehead Member Paul Matsudaira, and, along with Matsudaira, a member of MIT's Division of Biological Engineering. "First, they give us an idea of how a cell can manage to generate such enormous force; and second, they provide clues for how engineers might reconstruct these mechanisms for nano-scale devices."

France will present her findings Sunday, December 11, at the 45th Annual Meeting of the American Society for Cell Biology in San Francisco.

Scientists have known about this nano-spring for roughly 300 years, ever since Anton van Leeuwenhoek first observed the protozoan, Vorticella convallaria, through a hand-made microscope. 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 strongly Vorticella recoils, France and colleagues used a unique microscope to apply an extra load to the spring. The microscope, developed by Shinya Inoue and colleagues at the Marine Biological Laboratory in Woods Hole, MA, uses a spinning platform to increase the centrifugal force exerted against the protozoan.

In the past, researchers have measured Vorticella's ability to recoil its spring at 40 nano newtons of force and at a speed of eight centimeters per second, units of measurement that are typically too large to be relevant for biological processes. (These measurements, when scaled up to the size of a car engine, prove the Vorticella to be the more powerful of the two.) However, when France used the centrifuge microscope, she discovered that the spring was able to recoil against as much as 300 nano newtons of force.

"This is the maximum amount of power we can currently test," says France. "We suspect the coil is even more powerful."

France and colleagues also made an important link between the engine's fuel, calcium, and a major protein component of the stalk. This protein, centrin, belongs to a class of proteins that can be found in organisms ranging from green algae to humans. When the researchers introduced an antibody for the Vorticella centrin into the cell, the spring was no longer able to contract, indicating that the cell uses a powerful centrin-based mechanism, one that is unlike other known cellular engines.

"When it comes to creating nano devices, this is a great mechanism for movement," says France. "Rather than requiring electricity, this is a way to generate movement simply from a change in the chemical environment. Here, a simple change in calcium would power this spring." France and colleagues are now developing methods for replicating this mechanism in the lab.

Source: Whitehead Institute For Biomedical Research

Explore further: Innovative strategy to facilitate organ repair

add to favorites email to friend print save as pdf

Related Stories

Nano springs eternal; Protozoan 'engine' posts nano records

Dec 11, 2005

Looking through his handmade microscope in 1702, it was Anton van Leeuwenhoek who first described the workings of a nano machine. He observed the rapid contraction of a stalk tethering the cell body of a tiny protozoan, Vorticella ...

Recommended for you

Innovative strategy to facilitate organ repair

Apr 18, 2014

A significant breakthrough could revolutionize surgical practice and regenerative medicine. A team led by Ludwik Leibler from the Laboratoire Matière Molle et Chimie (CNRS/ESPCI Paris Tech) and Didier Letourneur ...

'Exotic' material is like a switch when super thin

Apr 18, 2014

(Phys.org) —Ever-shrinking electronic devices could get down to atomic dimensions with the help of transition metal oxides, a class of materials that seems to have it all: superconductivity, magnetoresistance ...

Thinnest feasible nano-membrane produced

Apr 17, 2014

A new nano-membrane made out of the 'super material' graphene is extremely light and breathable. Not only can this open the door to a new generation of functional waterproof clothing, but also to ultra-rapid filtration. The ...

User comments : 0

More news stories

NASA's space station Robonaut finally getting legs

Robonaut, the first out-of-this-world humanoid, is finally getting its space legs. For three years, Robonaut has had to manage from the waist up. This new pair of legs means the experimental robot—now stuck ...

Ex-Apple chief plans mobile phone for India

Former Apple chief executive John Sculley, whose marketing skills helped bring the personal computer to desktops worldwide, says he plans to launch a mobile phone in India to exploit its still largely untapped ...

Filipino tests negative for Middle East virus

A Filipino nurse who tested positive for the Middle East virus has been found free of infection in a subsequent examination after he returned home, Philippine health officials said Saturday.

Egypt archaeologists find ancient writer's tomb

Egypt's minister of antiquities says a team of Spanish archaeologists has discovered two tombs in the southern part of the country, one of them belonging to a writer and containing a trove of artifacts including reed pens ...