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:3/22/2017)... March 21, 2017   Neurotechnology , a ... technologies, today announced the release of the ... provides improved facial recognition using up to 10 ... single computer. The new version uses deep neural-network-based ... and it utilizes a Graphing Processing Unit (GPU) ...
(Date:3/20/2017)... March 20, 2017 At this year,s CeBIT Chancellor ... biometrics manufacturer DERMALOG. The Chancellor came to the DERMALOG stand together with ... this year,s CeBIT partner country. At the largest German biometrics company the ... fingerprint, face and iris recognition as well as DERMALOG´s multi-biometrics system.   ... ...
(Date:3/13/2017)... , March 13, 2017 Future of security: Biometric Face ... ... DERMALOGs Face Matching enables to match face pictures against ... basis to identify individuals. (PRNewsFoto/Dermalog Identification Systems) ... DERMALOG,s "Face Matching" is the fastest software for biometric Face Matching ...
Breaking Biology News(10 mins):
(Date:3/23/2017)... , March 23, 2017  SeraCare ... to global in vitro diagnostics manufacturers and ... the industry,s first multiplexed Inherited Cancer ... testing by next-generation sequencing (NGS). The Seraseq™ ... developed with input from industry experts to ...
(Date:3/23/2017)... ... March 23, 2017 , ... Ellen Matloff, president and CEO ... (CTC) as a 2017 Women of Innovation® finalist. Matloff will be among several ... , The dinner recognizes women accomplished in science, technology, engineering and math (STEM), ...
(Date:3/23/2017)... According to a report by Transparency Market ... due to the presence of a large pool of participants; however, ... , and Sigma-Aldrich, compete with each other in this market. With ... than 76% of this market in 2016.  ... As of now, a large number of ...
(Date:3/23/2017)... ... March 23, 2017 , ... Advanced Polymer Monitoring Technologies ... Dr. Sigmund “Sig” Floyd as Vice President ? Global Business Development. Dr. Floyd ... , “Dr. Floyd’s career has spanned 30 years in the chemicals and equipment ...
Breaking Biology Technology: