Navigation Links
Single mutation gives virus new target

PROVIDENCE, R.I. [Brown University] In a new study published online in the journal PLOS Pathogens, an international team of scientists showed that by swapping a single amino acid they could change the sugar to which the human BK polyomavirus will binds on the surface of cells. The BK polyomavirus lost the ability to bind its usual target sugar and instead "preferred" the same sugar as its cousin SV40 polyomavirus, which is active in monkeys.

The researchers were working in cell cultures with safe pseudoviruses, which cannot spread, so they did not show that the pseudovirus changed its infectivity from one species to another, but the finding provides a novel demonstration of how easily the binding target of a virus can change as its structure mutates and evolves.

Different cells have different bindings targets on their surfaces. A change in a virus's binding target preference can be a key step in changing how that virus would affect different cells in a victim or move on to a different species.

"I think it's one of the first, if not the first, times that a receptor switch of this nature has been identified," said Brown University virologist Walter Atwood, a corresponding author of the paper published Oct. 10, 2013. "There are dozens of viruses that use these kinds of sugars as receptors. What we're showing is that it doesn't take much to convert from using one type of sugar to using another type of sugar. It helps us to understand evolutionarily how these viruses may adapt to a new host."

Brown postdoctoral researcher Stacy-ann Allen, one of two lead authors on the paper, said the team learned of the single amino acid difference by comparing high-resolution structural models of the two polyomaviruses bound to their favorite sugars. Collaborators, including co-lead author Ursula Neu and co-correspondng author Thilo Stehle at the University of Tbingen in Germany, produced those models using nuclear magnetic resonance spectroscopy.

"We had the structures and sequences of both BK and SV40, and they are relatively similar in their amino acid identity," Allen said. "So when you see minute differences between them, you can target these differences to ask whether this difference allows for different infection in different hosts."

Sure enough, when Allen made the change at amino acid site 68 in the BK polyomavirus, it switched from binding the "ganglioside" sugar GD3 to binding with GM1.

Allen and colleagues tested this not only in cells in the lab, but also by dropping the viruses onto microarrays of binding target sugars.

And for even more confirmation, the Brown scientists sent the mutated BK viruses back to Germany for more NMR resolution.

"The NMR spectrum of the BK and the SV40 were identical," Atwood said, "They thought they had mixed up the samples. They were identical in terms of their ability to bind to GM1, the monkey receptor."

It may take several steps beyond a switch of receptor preference for a virus to infect new cells in the body or entirely new species, but such a switch could be a key step in more viruses than just the polyomavirus family, the scientists said. Others seem to switch preferences fairly quickly.

"Prominent examples include different serotypes of adenoviruses, the canine and feline paroviruses, as well as avian, swine, and human influenza viruses," they wrote in PLOS Pathogens.


Contact: David Orenstein
Brown University

Related biology news :

1. Improved smartphone microscope brings single-virus detection to remote locations
2. Genomes of cholera bacteria from Haiti confirm epidemic originated from single source
3. Single-cell transfection tool enables added control for biological studies
4. Philips CX50 xMATRIX now offers world-class interventional and diagnostic features on single portable system
5. How much a single cell breathes
6. Cat and mouse: A single gene matters
7. Dartmouth researchers find there is no single sexy chin
8. Sleator lab identifies single point mutation in Listeria monocytogenes
9. Single gene might explain dramatic differences among people with schizophrenia
10. Extremely high estrogen levels may underlie complications of single-birth IVF pregnancies
11. Little did we know about beetle diversity: Astonishing 138 new species in a single genus
Post Your Comments:
Related Image:
Single mutation gives virus new target
(Date:11/4/2015)... , November 4, 2015 ... market report published by Transparency Market Research "Home Security Solutions ... and Forecast 2015 - 2022", the global home security solutions ... bn by 2022. The market is estimated to expand ... from 2015 to 2022. Rising security needs among customers ...
(Date:10/29/2015)... 2015  Rubicon Genomics, Inc., today announced an ... its DNA library preparation products, including the ThruPLEX ... Plasma-seq kit. ThruPLEX Plasma-seq has been optimized for ... libraries for liquid biopsies--the analysis of cell-free circulating ... in cancer and other conditions. Eurofins Scientific is ...
(Date:10/27/2015)... 2015 Munich, Germany ... technology (ASGM) automatically maps data from mobile eye tracking ... , so that they can be quantitatively analyzed with ... Munich, Germany , October 28-29, 2015. SMI,s Automated ... mobile eye tracking videos created with SMI,s Eye ...
Breaking Biology News(10 mins):
(Date:11/25/2015)... (PRWEB) , ... November 25, 2015 , ... ... and the Organization of Black Aerospace Professionals (OPBAP) has been formalized with the ... other AMA team leaders met with OPBAP leaders Capt. Karl Minter and Capt. ...
(Date:11/25/2015)... ... November 25, 2015 , ... ... featured on AngelList early in their initial angel funding process. Now, they are ... individuals looking to make early stage investments in the microbiome space. In ...
(Date:11/24/2015)... 2015 Cepheid (NASDAQ: CPHD ) today ... following conference, and invited investors to participate via webcast. ...      Tuesday, December 1, 2015 at 11.00 a.m. Eastern Time ...      Tuesday, December 1, 2015 at 11.00 a.m. Eastern Time ... New York, NY      Tuesday, December 1, 2015 ...
(Date:11/24/2015)... ... November 24, 2015 , ... Copper is ... it is bound to proteins, copper is also toxic to cells. With a ... Polytechnic Institute (WPI) will conduct a systematic study of copper in the bacteria ...
Breaking Biology Technology: