Plasmid DNA Recovery Using Size-Exclusion and Perfusion ...
Finally, a second size-exclusion chromatography step was carried out to purify the plasmid DNA from other small molecular-weight contaminants. Analytical methods proved that the purified plasmid DNA had a purity of 95% after Sephacryl S1000. Plasmid identity was confirmed by restriction enzyme digestion. Biological activity of the purified plasmid was confirmed in vivo; immunized mice developed a positive antibody response against all HCV structural antigens. This procedure offers an alternative to traditional methods that use organic reagents, mutagenic and toxic compounds, and [more...]
Date: 2008-09-01 04:00:00
Productive Nanosystems: The Movies
Productive Nanosystems: The Movies by Eric Drexler on 30 January 2009 In his comment on Molecular Machine Assembly: The Movie, Drew Whitehouse reminded me of a set of excellent animations of biological productive nanosystems, work done by Drew Berry. These videos are based on scientific data describing molecular structure and function, and from what I’ve seen, Drew Berry’s work is the best of its kind. Below are the most complete and directly accessible videos I’ve found. Productive nanosystems are nanoscale machines that make atomically precise products under programmable control, and [more...]
Date: 2009-01-30 01:37:02
New twists in double helix discovery story are uncovered ...
Cold Spring Harbor, NY -- The story of the double helix's discovery has a few new twists. A new primary source -- a never-before-read stack of letters to and from Francis Crick, and other historical materials dating from the years 1950-76 -- has been uncovered by two professors at the Watson School of Biological Sciences at Cold Spring Harbor Laboratory (CSHL). The letters both confirm and extend current knowledge of the circumstances surrounding the epoch-making discovery of DNA's elegant double-helical structure, for which Crick, James D. Watson (now CSHL's chancellor emeritus) and Maurice [more...]
Date: 2010-10-10 04:39:02
Letters of DNA hunters reveal twists - Arkansas Online
The drama that surrounded Francis Crick and James Watson’s 1953 unveiling of the structure of DNA is no secret — Watson described the heated competition between two British research groups in his best-selling book, The Double Helix. This story is only available from the Arkansas Online archives. Stories can be purchased individually for $1.95. Click the link below to search for this story in the archives. If the search doesn't yield any results, contact the Arkansas Democrat-Gazette library at (501) 378-3851 with the section, date and page information below. » Click here to search the [more...]
Date: 2010-10-03 09:00:49
DNA art imitates life: Construction of a nanoscale Mobius strip
The circulations of earth's warmer and cooler ocean currents for example, describe a Möbius shape. Other topological structures are common to biological systems, particularly in the case of DNA, the 3 billion chemical bases of which are packed by the chromosome inside the cell, using topological structures. "In bacteria, plasmid DNA is wound into a supercoil," Yan explains. "Then the enzymes can come in and cut and reconfigure the topology to relieve the torsion in the supercoil so that all the other cellular machinery can have access to the gene for replication, transcription and so [more...]
Date: 2010-10-08 21:50:00
$1.00 - Bio2010
DNA polymerase I catalyzes the elongation of the new DNA strands in prokaryotes. c. The lagging strand is synthesized as Okazaki fragments. d. The leading strand elongates from its 3' to 5' end. e. Helicases initiate replication by winding the two strands together. Save Answer 16. (Points: 5) The appropriate adjective to describe DNA replication is a. progressive. b. lytic. c. semiconservative. d. nondisruptive. e. natural. Save Answer 17. (Points: 5) In a sample of double-stranded DNA from a human, you have determined that 20 percent of the nitrogenous base is adenine. What percentage should [more...]
Date: 2008-08-05 01:50:23
New Repair Mechanism Has Been Discovered by Researchers « New ...
In 1953, the molecular structure of DNA was discovered by Watson and Francis Crick. Since then, one of the most amazing discoveries in genetic research has been the multitudes of protein machines that repair DNA. Recently, a “fundamentally new” DNA repair mechanism was discovered by researchers at Vanderbilt University! Science Daily describes it this way, “Tucked within its double-helix structure, DNA contains the chemical blueprint that guides all the processes that take place within the cell and are essential for life. Therefore, repairing damage and maintaining the integrity of [more...]
Date: 2010-10-13 08:16:14
the Foresight Institute » Making and opening a Mobius strip with ...
The already numerous uses of DNA origami have been still further extended by the demonstration of topological reconfiguration—specifically, turning a 50-nanometer diameter Möbius strip into an open ring of twice the diameter by cutting along its centerline by removing the DNA “staples” along the centerline. The accomplishment by Scientists at the Biodesign Institute at Arizona State University, led by Hao Yan and Yan Liu, is described on the AAAS science news site EurekAlert! by science writer Richard Harth “DNA art imitates life: Construction of a nanoscale Mobius [more...]
Date: 2010-10-13 04:52:03
[DNA: Replication, Repair, and Recombination] Inefficient ...
Inefficient Proofreading and Biased Error Rates during Inaccurate DNA Synthesis by a Mutant Derivative of Saccharomyces cerevisiae DNA Polymerase δ* Stephanie A. Nick McElhinny ‡ , Carrie M. Stith § , Peter M. J. Burgers § and Thomas A. Kunkel ‡ ‡Laboratory of Molecular Genetics and Laboratory of Structural Biology, NIEHS, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina 27709 and the §Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110 1 To whom [more...]
Date: 2007-01-19 08:00:00
Molecular Photofitting: Predicting Ancestry and Phenotype Using ...
Molecular Photofitting: Predicting Ancestry and Phenotype Using DNA by Tony Nick Frudakis Publisher: Academic Press; 1 edition (September 21, 2007) | ISBN: 0120884925 | Pages: 712 | PDF | 14.13 MBIn the ~ of battle of forensics, there is a critical need for genetic tests that be able to function in a predictive or inferential sense, before suspects have been identified, and/or notwithstanding crimes for which DNA evidence exists but eye-witnesses do not. Molecular Photofi>tting fills this stand in want of by describing the process of generating a physical description of each individual from [more...]
Date: 2010-10-05 09:23:58
The Purification of Plasmid DNA for Clinical Trials Using Membrane ...
ABSTRACTMembrane chromatography offers a good solution to the challenge of developing an efficient chromatographic procedure for plasmid DNA purification. The large convective pores of anion exchange membranes allow plasmid DNA to access all the anionic binding sites of the membrane at high flow rates. Here we demonstrate that the pIDKE2 plasmid can be purified from a recombinant Escherichia coli lysate using a Sartobind D membrane combined with size exclusion chromatography to render material with 95% purity and an average yield of 50%. This process yields therapeutically suitable plasmid [more...]
Date: 2010-02-01 05:00:00
Opinio Juris » Blog Archive » African Cyberpunk, DNA Hacking, and ...
African Cyberpunk, DNA Hacking, and the Problems of Transnational Regulation There’s a post that’s been making the rounds in the science fiction blogosphere that warrants note by those interested in international law, especially in regards to issues of international trade, development, and regulation. The piece is by Ghanaian writer Jonathan Dotse and it concerns the rise of African cyberpunk. Before getting to Dotse’s post, though, a couple of words on cyberpunk itself. Cyberpunk is a sci-fi style that arose primarily among U.S. and Canadian writersin the 1980’s. Setting aside the [more...]
Date: 2010-05-18 07:15:08
The MolBio Carnival, third edition | Alles was lebt | ScienceBlogs ...
There are a few methods to do this around, so why should one more on the list be interesting to us? Well, the new one uses next-generation sequencing to look at RNA folding on a whole-genome scale! David presents the paper in a journal club style, summarizing the interesting new data and methods, but also discussing some of the shortcomings. 3) Next up, we have a series of posts by Christopher Dieni at "Bitesize Bio" on the protein modification many of you probably know and love - phosphorylation. In the first post, he gives an overview of the topics he will write about in the following [more...]
Date: 2010-10-04 21:15:46
NOT A CHIMP: Serotonin selectively influences moral judgment and ...
However, look at a recent map of the chromosomes of chimps and humans, aligned side by side, produced by researchers who have mapped all inversions - end-on-end flips of large chunks of DNA - and the chromosomes are all but blotted out by a blizzard of red lines denoting inverted sequence. Now you become overwhelmed by how much structural change has occurred between the two genomes in just 6 million years. True, not all inversions result in changes in the working of genes - but many do - and inversions might even have been responsible for the initial divergence of chimp ancestor from human [more...]
Date: 2010-10-05 09:29:00
ISPUB - What's There In Our Genes? A Case For A More Inclusive And ...
We need better reviews, use of both qualitative and quantitative data as well as much more rigorous testing of newer and older models. Only then may we make full use of this large amount of data that has already been collected over the years. What we have described here, for now, presents part of the picture seen from the Indian subcontinent as an example. However, this situation is probably true of other parts of the world as well, perhaps even those areas where it has been assumed that the data is likely to be homogenous. Thus, even biological anthropologists need to add new sensitivities [more...]
Date: 2010-10-07 04:39:48
The Vatic Project: Why Great Minds Can't Grasp Consciousness
Unlike some other scientists -- most notably the late Francis Crick, co-discoverer of the structure of DNA, and his colleague Christof Koch, a professor of computation and neural systems at Caltech -- who believed that different aspects of consciousness like visual awareness are encoded by specific neurons, Greenfield thinks that consciousness involves large groups of nonspecialized neurons scattered throughout the brain. Important for Greenfield's theory is a distinction between 'consciousness' and 'mind,' terms that she says many of her colleagues use interchangeably, but which she [more...]
Date: 2010-10-12 23:00:00
CIENCIASMEDICASNEWS: NCBI launches the Database of Genomic ...
The database was developed by the National Center for Biotechnology Information (NCBI), a division of the National Library of Medicine (NLM) at NIH. The human genome is made up of approximately 3 billion base pairs of DNA arranged into 46 chromosomes. In recent years, scientists have discovered that very large stretches of the genome — on the order of millions of base pairs of DNA — can be different in seemingly normal individuals. It had long been known that such large-scale genomic changes existed, but it was thought that they were rare and when present led to known disorders such as [more...]
Date: 2010-10-01 13:12:00
FTDNA Family Finder - ForumBiodiversity.com » Anthropology ...
I like what is described in the bold face, it would be quite convenient to be able to have direct contact with project members, but for myself it won't be of much use considering only a fraction of my cousins are FTDNA users and I already have my genealogy composed. It would be quite useful for others though who are interested in contacting those long lost cousins and such. One thing I do like is this could lead to more security when sharing GEDCOM's and such, with things like Ancestry.com your files, if made public, can be downloaded and viewed by anyone, this Family Finder thing could help [more...]
Date: 2010-02-16 22:00:09
Cheek swab for lung cancer: breakthrough in biomedical optics ...
Not only can nanocytology help detect cancer early, it can shed light on the fact that these small changes in the cell structure are very telling. Changes in the DNA are also very revealing. For decades, scientists have known that smoking causes cancer because it damages the DNA. Now British researchers have uncovered the link between smoking and epigenetic changes in DNA. “Until now, however, there has been no direct evidence that smoking induces DNA methylation in humans,” Cancer Research UK Institute of Cancer Studies Dr Yuk Ting Ma said in a statement. “DNA methylation is a type of [more...]
Date: 2010-10-11 17:01:25
The Boss Part 2 - Getting To Know DNA: Structure 10/4/10
Mr. Jesse Craig Centennial, Colorado, United States I am in my 13th year of teaching Science at Arapahoe High School. Our department is in the process of finding ways to put our students in charge of their own learning. Podcasts of my classroom teaching allow my students the opportunity to review important material. Blogging allows my students to continue class discussions outside the walls of the classroom. View my complete profile This blog hosts podcasts created by Mr. Jesse Craig at Arapahoe High School in Centennial, CO. The podcasts are designed to provide outside-of-class help to my [more...]
Date: 2010-10-04 20:48:16
» Letters Reveal Rivalries in Discovery of DNA Structure ...
The British researchers wanted desperately to find the DNA structure before Pauling–but not enough to collaborate with each other. A description of some of what the newly found letters reveal is at http://nyti.ms/c4GAfh. An article in the journal Nature (http://bit.ly/bIMWXO) by the discoverers of the letters provides more information and some facsimile copies. Though much has already been written about the discovery of DNA, letters from and to someone who was instrumental in the original discovery can serve as excellent pedagogical tools. The fact that scientists share the rivalries and [more...]
Date: 2010-10-03 16:24:41
Structure of an Ebf1:DNA complex reveals unusual DNA recognition ...
Dear Colleagueaaa, Here is an article you may find interesting. Elucidation of a C-Rich Signature Motif in Target mRNAs of RNA-Binding Protein TIAR. http://biowizard.com/abstract.php?pmid=17682065 Kim HS, Kuwano Y, Zhan M, Pullmann R Jr, Mazan-Mamczarz K, Li H, Kedersha N, Anderson P, Wilce MC, Gorospe M, Wilce JA Mol Cell Biol. 2007 Aug 6; PMID: 17682065 BioWizard [more...]
Date: 2010-10-06 13:48:02
What Is The Structure Of Dna
For example, what is the structure of dna, what are the branches of environmental science and what is the purpose of the sierra club. Job offerings are on the increase within the environmental sector as a result of global warming. Legend Illustration of the double helical structure of the DNA molecule. The structure of DNA is illustrated by a right handed double helix, with about 10 nucleotide pairs per Legend Illustration of the double helical structure of the DNA molecule. The structure of DNA is illustrated by a right handed double helix, with about 10 [more...]
Date: 2010-10-09 13:40:06
Roland San Juan: Terrifying Future - Scientists Mixing Human ...
Like the ancient Watchers before him (Watchers were fallen angels that mingled human dna with animals and their seed to produce Nephilim. More on this will be discussed later), Bostrom envisions giving life to Nietzsche’s Overman (posthumans) by remanufacturing men with animals, plants, and other synthetic life-forms through the use of modern sciences including recombinant dna technology, germ-line engineering, and transgenics (in which the genetic structure of one species is altered by the transfer of genes from another). Given that molecular biologists classify the functions of genes [more...]
Date: 2010-10-13 02:15:00
The Structure of the DNA Molecule
Working with nucleotide models made of wire, Watson and Crick attempted to put together the puzzle of DNA structure in such a way that their model would account for the variety of facts that they knew described the molecule. Once satisfied with their model, they published their hypothesis, entitled “Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid” in the British journal Nature (April 25, 1953. volume 171:737-738.) It is interesting to note that this paper has been cited over 800 times since its first appearance! Here are their words: “…This (DNA) [more...]
Date: 2010-09-28 22:15:45
Next American City » Buzz » The High Cost of Electric Cars
The High Cost of Electric Cars Diana Lind | Oct 13th, 2010 | Topics: Infrastructure | Region: Central | Cities: Detroit, New York | 0 “Am I the only one who sees GoogleCars as an improved means to an unimproved, even catastrophic end? Ice caps are melting: have a robot car!” So wrote Alex Steffen of Worldchanging on Twitter earlier this week. To reply: Alex, you’re not the only one. I was at the Carnegie Council for Ethics in International Affairs the other day to listen to a panel discussion on sustainable societies. It was a thought-provoking conversation with speakers promoting [more...]
Date: 2010-10-13 08:38:27