Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New images capture virus in extraordinary detail

08.02.2006


Fifty years after MIT researchers pioneered the use of electron microscopy to study viruses, MIT scientists have helped produce the most detailed images yet of the tiny infectious agents .



The images, which show for the first time a virus poised to inject its genetic material into a host cell, grace the cover of the Feb. 2 issue of Nature.

Scientists have known for decades that viruses infect cells by injecting their genetic material, either DNA or RNA, into host cells, but even with electron microscopy, "we could never see the details of that aspect of it," said Jonathan King, an MIT professor of biology and one of the authors of the paper.


The researchers, led by Wen Jiang and Wah Chiu of the National Center for Macromolecular Imaging at Baylor College of Medicine, focused on viruses that infect bacteria, known as bacteriophages. Their paper diagrams the structure of a virus that infects Salmonella bacteria.

The photographs clearly show a long coil of DNA dangling inside the viral shell, waiting to be ejected via a protein channel just inside the shell exterior.

"Now you can see the end of the DNA. You can see the cylinder holding it, poised to go into the cell," said King.

To create the detailed images, the researchers photographed about 15,000 virus particles and ran them through a complex computer program that compared the photographs and constructed a 3-D model based on common features shared by the images.

The researchers also improved image quality by rapidly freezing the viruses before photographing them. The amorphous ice that forms as a result of the rapid freezing protects and preserves the virus structure, unlike regular crystallized ice, King said.

This project builds on a long legacy of viral research at MIT, King said. In 1969, MIT Professor Salvador Luria shared the Nobel Prize in physiology or medicine with Max Delbruck and Alfred Hershey for work on the genetic structure and replication mechanisms of viruses.

Luria, who came to MIT in 1959, was the first scientist to show the structure of bacteriophages.

"That really brought these bacterial viruses to the fore, and they’ve continued to be important for half a century," King said.

Bacteriophages were used in crucial experiments showing that DNA is the genetic material and determining that translation of genetic material into proteins is based on a triplet code.

Luria’s legacy at MIT’s biology department is carried on today, said King. Shortly after World War II, the Institute got one of the first electron microscopes in the United States, and Luria molded the direction of the department, said King, who arrived at MIT in 1970 after working with Delbruck at Caltech.

"It was (Luria’s) appointment that led to the department having its current character, which is a leader in molecular biology," King said.

MIT research scientist Peter Weigele is also an author on the imaging paper.

Funding for the imaging project was provided by the National Institutes of Health and the Robert Welch Foundation. The electron microscope images were taken at the National Center for Macromolecular Imaging at Baylor College of Medicine.

Elizabeth A. Thomson | MIT News Office
Further information:
http://www.mit.edu

More articles from Life Sciences:

nachricht Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz

nachricht Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>