Navigation Links
Crammed with charged DNA, pressure rises inside virus

It could be an artist’s depiction of someone’s stomach before and after a rather decadent meal. But it is a 3-D cryoelectron microscope reconstruction of the cross-section of a virus, before and after cramming itself full of its own DNA.

The virus, phi29, has a tiny motor that pumps its DNA into the capsid—outer shell—during the assembly process. The potential energy of the tightly coiled DNA may help phi29 inject its genetic material into the bacterial cells it infects. Now a team led by physicists at the University of California, San Diego has used laser tweezers to measure the forces exerted by the motor as it pushes the DNA into the capsid.

“The virus’ motor has to do mechanical work to overcome two factors that create resistance,” said Douglas Smith, an assistant professor of physics at UCSD who headed the team that published the discovery this week in the early on-line edition of Proceedings of the National Academy of Sciences. “First, the DNA must be forced to bend. Second, the electrostatic repulsion of the DNA’s negatively charged backbone must be overcome. We found that the positively charged ions in the solution are critical to overcoming this repulsion. Without the right combination of positively charged ions, the virus could not force all of its DNA into the capsid.”

The researchers discovered that the forces in the capsid are slightly higher than predicted by theoretical calculations. They say this may be because the packed DNA is less ordered than assumed in the calculations.


'"/>

Source:University of California - San Diego


Page: 1

Related biology news :

1. Gene therapy to lower blood pressure just enough
2. Use of high hydrostatic pressure to inactivate Hepatitis A virus in oysters studied
3. Researchers learn how blood vessel cells cope with their pressure-packed job
4. Genes affecting blood pressure change as children become adults
5. How nice, brown rice: Study shows rice bran lowers blood pressure in rats
6. Blame the brain for high blood pressure
7. Its OK for men with high blood pressure to have a drink or two, new study finds
8. 8 plants from South Africa may hold potential for treating high blood pressure
9. First real-time view of developing neurons reveals surprises, say Stanford researchers
10. Controlling wildlife trade key to preventing health crises, study says
11. Patient-choice C-section rate rises 36%: HealthGrades study
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:3/28/2017)... 28, 2017 The report "Video ... Monitors, Servers, Storage Devices), Software (Video Analytics, VMS), and ... Global Forecast to 2022", published by MarketsandMarkets, the market ... is projected to reach USD 75.64 Billion by 2022, ... The base year considered for the study is 2016 ...
(Date:3/24/2017)... Mar 24, 2017 Research and Markets has ... Market Analysis & Trends - Industry Forecast to 2025" report ... ... at a CAGR of around 15.1% over the next decade to ... report analyzes the market estimates and forecasts for all the given ...
(Date:3/22/2017)... , March 21, 2017   Neurotechnology ... object recognition technologies, today announced the release of ... (SDK), which provides improved facial recognition using up ... on a single computer. The new version uses ... improve accuracy, and it utilizes a Graphing Processing ...
Breaking Biology News(10 mins):
(Date:4/27/2017)... ... April 27, 2017 , ... ... today announced their digital pathology technology has the potential to eliminate subjectivity in ... centers in The Netherlands as part of the 2017 ISBI CAMELYON Digital ...
(Date:4/27/2017)... ... April 27, 2017 , ... ... Summit ( http://www.paintherapeuticsummit.com ) is coming to San Diego, CA on September 27-28, ... to learn about the latest advances in the treatment of various types of ...
(Date:4/27/2017)... ... April 27, 2017 , ... ... a comprehensive rebrand and a name change to Fluence Analytics. , ... laboratory monitoring of polymer and biopharmaceutical manufacturing processes and R&D applications. The ...
(Date:4/27/2017)... 27, 2017  Pendant Biosciences, Inc. (formerly Nanoferix, Inc.), ... and drug delivery technologies, today announced that it has ... Toronto . Shawn ... Biosciences, noted, "We are excited to become part of ... and are honored to be the first ...
Breaking Biology Technology: