Featured Research

from universities, journals, and other organizations

Proton mechanism used by flu virus to infect cells discovered

Date:
October 21, 2010
Source:
Iowa State University
Summary:
Chemists have discovered the shuttle mechanism that relays protons from a healthy cell into a flu virus. The proton movement is an important part of the flu virus life cycle.

Mei Hong of Iowa State University and the Ames Laboratory, left, and Fanghao Hu of Iowa State used solid-state nuclear magnetic resonance spectroscopy to investigate the proton channel that connects a flu virus to a healthy cell.
Credit: Photo by Bob Elbert/Iowa State University

The flu virus uses a shuttle mechanism to relay protons through a channel in a process necessary for the virus to infect a host cell, according to a research project led by Mei Hong of Iowa State University and the Ames Laboratory.

Related Articles


The findings are published in the Oct. 22 issue of the journal Science.

Hong, an Iowa State professor of chemistry and an associate of the U.S. Department of Energy's Ames Laboratory, said her research team used solid-state nuclear magnetic resonance (NMR) spectroscopy to determine the structure and workings of the proton channel that connects the flu virus to a healthy cell.

She said a full understanding of that mechanism could help medical researchers design drugs that stop protons from moving through the channel.

That proton channel is an important part of the life cycle of a flu virus. The virus begins an infection by attaching itself to a healthy cell. The healthy cell surrounds the virus and takes it inside through a process called endocytosis. Once inside the cell, the virus uses a protein called M2 to open a channel. Protons from the healthy cell flow through the channel into the virus and raise its acidity. That triggers the release of the virus' genetic material into the healthy cell. The virus then hijacks the healthy cell's resources to replicate itself.

Hong and her research team -- Fanghao Hu, an Iowa State doctoral student in chemistry; and Wenbin Luo, a former Iowa State doctoral student who is now a spectroscopist research associate at Penn State University -- focused their attention on the structure and dynamics of the proton-selective amino acid residue, a histidine in the transmembrane part of the protein, to determine how the channel conducts protons. Their work was supported by grants from the National Science Foundation and the National Institutes of Health.

Two models had been proposed for the proton-conducting mechanism:

  • A "shutter" channel that expands at the charged histidine because of electrostatic repulsion, thus allowing a continuous hydrogen-bonded water chain that takes protons into the virus.
  • Or a "shuttle" model featuring histidine rings that rearrange their structure in some way to capture protons and relay them inside.

Hong's research team found that the histidine rings reorient by 45 degrees more than 50,000 times per second in the open state, but are immobile in the closed state. The energy barrier for the open-state ring motion agrees well with the energy barrier for proton conduction, which suggests that the M2 channel dynamically shuttles the protons into the virus. The chemists also found that the histidine residue forms multiple hydrogen bonds with water, which helps it to dissociate the extra proton.

"The histidine acts like a shuttle," Hong said. "It picks up a proton from the exterior and flips to let it get off to the interior."

The project not only provided atomic details of the proton-conducting apparatus of the flu virus, but also demonstrated the abilities of solid-state NMR.

"The structural information obtained here is largely invisible to conventional high-resolution techniques," the researchers wrote in their Science paper, "and demonstrates the ability of solid-state NMR to elucidate functionally important membrane protein dynamics and chemistry."


Story Source:

The above story is based on materials provided by Iowa State University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Fanghao Hu, Wenbin Luo, and Mei Hong. Mechanisms of Proton Conduction and Gating in Influenza M2 Proton Channels from Solid-State NMR. Science, 22 October 2010 330: 505-508 DOI: 10.1126/science.1191714

Cite This Page:

Iowa State University. "Proton mechanism used by flu virus to infect cells discovered." ScienceDaily. ScienceDaily, 21 October 2010. <www.sciencedaily.com/releases/2010/10/101021141445.htm>.
Iowa State University. (2010, October 21). Proton mechanism used by flu virus to infect cells discovered. ScienceDaily. Retrieved April 21, 2015 from www.sciencedaily.com/releases/2010/10/101021141445.htm
Iowa State University. "Proton mechanism used by flu virus to infect cells discovered." ScienceDaily. www.sciencedaily.com/releases/2010/10/101021141445.htm (accessed April 21, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Tuesday, April 21, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Going Ape: Sierra Leone Chimpanzees Hail Ebola Retreat

Going Ape: Sierra Leone Chimpanzees Hail Ebola Retreat

AFP (Apr. 21, 2015) As money runs out at Tacugama Chimpanzee Sanctuary in Sierra Leone, around 85 chimps are facing homelessness. The centre closed when the Ebola epidemic was ravaging the country but now that closure is beginning to look permanent. Video provided by AFP
Powered by NewsLook.com
Blue Bell Recalls All Products

Blue Bell Recalls All Products

AP (Apr. 21, 2015) Blue Bell Creameries voluntary recalled for all of its products after two samples of chocolate chip cookie dough ice cream tested positive for listeria, a potentially deadly bacteria. Blue Bell&apos;s President and CEO issued a video statement. (April 21) Video provided by AP
Powered by NewsLook.com
Research Says Complex Tools Might Not Be 'Our Thing' Anymore

Research Says Complex Tools Might Not Be 'Our Thing' Anymore

Newsy (Apr. 21, 2015) The use of complex tools has often been seen as a defining characteristic of humanity, but that notion is now in question. Video provided by Newsy
Powered by NewsLook.com
Deepwater And Dolphins: The Oil Spill's Impact 5 Years On

Deepwater And Dolphins: The Oil Spill's Impact 5 Years On

Newsy (Apr. 20, 2015) Five years on, the possible environmental impact of the Deepwater Horizon spill includes a sustained die-off of bottlenose dolphins, among others. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins