Navigation Links
Preventing cells from getting the kinks out of DNA
Date:5/24/2010

or cell-killing DNA break.

While the protein structure of these topoisomerases is known, the details of the chemical reactions that take place between the enzyme and DNA, and their reaction with the drugs that bind both, remain a mystery, Berger said. In fact, one of the main puzzles is why antibiotics like ciprofloxacin (Cipro) and anti-cancer drugs like etoposide, which vary widely in structure, have the same effect: jamming the enzyme and causing a break in the double-stranded DNA helix.

Berger and his colleagues found a way to obtain a picture that shows the interaction of the protein bound to DNA. The next step is to do the same for a drug bound to the protein/DNA complex, getting an image of exactly how these drugs interfere with the knot elimination machinery.

"The technique we used to trap this complex so that we could actually crystallize it and image it we think now gives us a handle on how to go after drug-bound complexes of human topoisomerases that have long eluded the field," said Berger, who also is a staff scientist at Lawrence Berkeley National Laboratory (LBNL).

The scientists' new picture of the enzyme bound to DNA also turned up something totally unexpected. Most enzymes that bind DNA to snip or stitch it together use two metal ions typically two magnesium ions to catalyze the reaction. Berger found that type II topoisomerases, which target double-stranded DNA, make use of only one of their two magnesium ions and instead use the amino acid arginine as their second catalytic center. The second magnesium merely provides structural integrity to the protein.

"We stumbled upon a new kind of cleavage mechanism for DNA, an example of a protein that uses a completely new approach for the same mechanism," Berger said. "It speaks to the evolutionary plasticity and adaptability of nature that continuously amazes us with finding new ways to carry out reactions that it needs to perform."

Berger now plans
'/>"/>

Contact: Robert Sanders
rsanders@berkeley.edu
510-643-6998
University of California - Berkeley
Source:Eurekalert

Page: 1 2 3

Related biology news :

1. Vaccines preventing pneumococcal disease protect African children with sickle-cell disease
2. Preventing gastric cancer with antibiotics
3. Preventing or reversing inflammation after heart attack, stroke may require 2-pronged approach
4. New finding in cell migration may be key to preventing clots, cancer spread
5. UC Davis research confirms benefits of calcium and vitamin D in preventing fractures
6. New study suggests minke whales are not preventing recovery of larger whales
7. Mango effective in preventing, stopping certain colon, breast cancer cells
8. Preventing allergies
9. Climate change poker: The barriers which are preventing a global agreement
10. NIH funds work at WPI on regenerating heart tissue and preventing urinary tract infections
11. Preventing ear infections in the future: Delivering vaccine through the skin
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/22/2015)... , Jan. 21, 2015  Analyst Report Issued by Small ... Brands report showed that planet-wide, transactions at merchants on the ... the total number of credit, debit, and prepaid cards reached ... were victims of fraudulent card usage in 2012, and credit ...
(Date:1/22/2015)... Infinisource has launched its new NXG series of time clocks ... a higher standard for collecting attendance and labor data and ... installation, touch screen interface and seamless connection to cloud-based iSolved, ... solution for the small to mid-size employer. The ...
(Date:12/22/2014)... DENVER , Dec. 22, 2014  The 2014 Holiday ... industry as Acuity Market Intelligence reports that the long ... Acuity forecasts that intensifying demand for smart phones, tablets, ... a global market of 2.5 billion users with nearly ...
Breaking Biology News(10 mins):$4.80 Near Term Price Target with "Buy" given by CapRock Research for NXT-ID, Inc. (NASDAQ: NXTD) issued by Small Cap IR 2Infinisource's NXG series sets new time clock standard 2First Season of Holiday Shopping with Mobile Biometric Payments Wraps Up With a Present for Biometrics Industry: A Rosy Forecast for More Than 2 Billion Users of 4.8 Billion Mobile Biometric Devices by 2020 2
... as emerging leaders in the field of nursing informatics, ... participate in a jointly supported Nursing Informatics Emerging Leaders ... criteria, including a mid-level position in informatics in a ... a registered nurse, and the ability to make a ...
... University,s Philip R. LeDuc and his collaborators in Massachusetts ... protein that could ultimately unlock the mystery of how ... in the mechanics of biological processes in people. ... of a protein that helps control cell behavior from ...
... , NORWOOD, Mass. , Jan. 12 Molecular ... tools for applications in personalized medicine, today announced it has completed ... Venture ( Waltham, MA ) led the round with participation from ... Bioscience Partners ( Boston, MA ). , The financing will ...
Cached Biology News:2 nurses emerge as leaders in informatics 2Carnegie Mellon's Philip LeDuc discovers new protein function 2Molecular Biometrics Closes $12.5 Million Series B Equity Funding 2Molecular Biometrics Closes $12.5 Million Series B Equity Funding 3Molecular Biometrics Closes $12.5 Million Series B Equity Funding 4Molecular Biometrics Closes $12.5 Million Series B Equity Funding 5
(Date:1/23/2015)... BioPharma Inc. (NASDAQ: ARRY ) today announced ... Pharma AG to acquire worldwide rights to encorafenib (LGX818), ... agreement is conditional on the closing of transactions announced by ... are expected to close in the first half of ...
(Date:1/22/2015)... 22, 2015 GEA Niro Soavi the ... laboratory homogenizer, the PandaPLUS 2000, which is ideal for ... and cell disruption . This compact laboratory homogenizer ... juices, liquid food, food additives and ingredients as well ...
(Date:1/22/2015)... Crystal Diagnostics (CDx) Xpress System, a rapid ... AOAC-PTM Certifications for the six non-O157 Shiga toxin-producing E. coli ... to as STEC or the “Big-6”) as well as Escherichia ... per 325 g of raw ground beef and raw beef ...
(Date:1/22/2015)... Selexis SA, a serial innovation company ... (RCBs) used for drug discovery to commercial manufacturing, announced ... Next-Generation Sequencing (NGS) data packages. The NGS ... by ensuring the integrity of the gene, validation of ...
Breaking Biology Technology:Array Announces Agreement To Acquire ENCORAFENIB (LGX818) 2Array Announces Agreement To Acquire ENCORAFENIB (LGX818) 3Array Announces Agreement To Acquire ENCORAFENIB (LGX818) 4Array Announces Agreement To Acquire ENCORAFENIB (LGX818) 5Array Announces Agreement To Acquire ENCORAFENIB (LGX818) 6Array Announces Agreement To Acquire ENCORAFENIB (LGX818) 7GEA Niro Soavi Announces the PandaPLUS 2000 Homogenizer for Processing New Applications for Nanoemulsions and Cell Disruption 2Crystal Diagnostics Awarded AOAC-PTM Accreditation for the Rapid Detection of “Big 6” E.coli Food Pathogens 2Selexis Generated Research Cell Banks Now Fully Sequenced Using Next-Generation Sequencing 2
... ... of layoffs. Pharmaceutical companies, though, laid off fewer employees in May than in any previous ... Seattle, ... rebound month, with 24,000 new jobs created in the industry -- 7,000 more than in ...
... Testing , , CINCINNATI, June 23 ... leading provider of physician office-based patient-education programs, reports that ... 16.9 percent more patients had PSA tests (prostate cancer ... cancer screening) compared to patients in practices without ...
... SAO PAULO, June 23 What does sugarcane have to ... experience with sugarcane as a feedstock for ethanol. In place ... a fossil fuel with,renewable energy has saved some 600 million ... for six billion trees to achieve the same,results. , ...
Cached Biology Technology:The MedZilla Report: May 2009 Employment Outlook for Biotech/Pharma/Health 2The MedZilla Report: May 2009 Employment Outlook for Biotech/Pharma/Health 3Healthy Advice Networks Announces Improved Patient Outcomes in Physicians' Offices with Healthy Advice Programs 2Sugarcane as a Key Element Against Global Warming to be Highlighted at Green Week in Brussels 2Sugarcane as a Key Element Against Global Warming to be Highlighted at Green Week in Brussels 3Sugarcane as a Key Element Against Global Warming to be Highlighted at Green Week in Brussels 4
Use the DUALmembrane kit 3 to carry out DUALmembrane interaction analysis and cDNA library screening to characterize interactions between integral membrane proteins and to identify novel interaction ...
Mouse Limitin MAb (Clone 183727)...
...
Human/Mouse/Rat p38 alpha Affinity Purified PAb...
Biology Products: