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 Cryo-electron microscopy achieves unprecedented resolution using new computational methods
24.03.2017 | DOE/Lawrence Berkeley National Laboratory

nachricht How cheetahs stay fit and healthy
24.03.2017 | Forschungsverbund Berlin e.V.

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>