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Originally the position had a G:C pair. After the mutation, there is an oxoG:C pair. Upon replication, the strand with C will pair to G and the original pair will be created as expected. However, since oxoG can also pair with A, the strand with oxoG may form an oxoG:A pair. Another round of replication gives the products T:A and oxoG:A. Thus the G in the ...


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It depends on the seed and fruit you're talking about. The amount of DNA in your crushed up sample of plant matter depends on only one thing--how many cells are in your sample. Look at this diagram of a kernel of corn (U of Indiana): There are different cell densities in each area--in the endosperm, the cells can be huge (and therefore have a lower ...


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Pitch is not a great word for this, as its meaning is ambiguous. It's hard to find a universal nomenclature for DNA geometry, but see the "Base pair geometry" section of this wikipedia page. The relevant property is what they call "opening". From the biochemistry textbook by Berg: To explain in words, if the glycosidic bonds (which attach the nucleic ...


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Dihydrouracil oxidase can catalyse the reduction of uracil to dihydrouracil in the presence of hydrogen peroxide. The reduction of uracil to dihydrouracil can also be catalysed by dihydrouracil dehydrogenase using NADH. According to this paper, 5,6-dihydroxycytosine can be formed by treating cytosine or DNA with osmium tetroxide, an extremely strong ...


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PSI-BLAST creates a protein profile of similar proteins (essentially a scoring matrix based on multiple sequence alignments) that are then used for further DB searches. On the nucleotide level this simply does not make much sense, especially for short sequences. For one, there is much less potential variability which is probably worse for non-coding ...


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Addition to Jvrek's answer based on the comments. Most RNA degradation mechanisms catalysed by different RNAses (RNAse-A and RNAse-S, for example), involve the 2'-OH. Therefore the repertoire of RNAses is selective towards RNA and not DNA because of the 2'-OH.         ...


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Nice question which leads to the fundamentals of DNA and RNA. DNA (Deoxyribonucleic acid) is the core of life in Earth, every known living organism is using DNA as their genetic backbone. DNA is so precious and vital to eukaryotes that its kept packaged in cell nucleus, its being copied but never removed because it never leaves the safety of nucleus. DNA ...


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The name is derived from the sugar which is bound to the base. For RNA it is Ribose (that why it is called ribonucleic acid) and for DNA it is Deoxyribose (hence the name deoxynucleic acid). The deoxyribose is missing an OH-group at positition 2 of the sugar ring, the name literally means "without oxygen". See the image below (from here) for further ...


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I opened Lehninger (Principles of biochemistry, 4th ed.) on page 293. The slow Cytosine deamination reaction seems innocuous enough, but is almost certainly the reason why DNA contains thymine rather uracil C is deaminated to U in a rate of 10^-7 in 24 hours, which means 100 mutations a day for a mammalian cell which would have lead to a A-U genome ...


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If you have access to a centrifuge, either spin columns or phenol:chloroform will give very pure, high-quality DNA. Even with dirty methods, you can re-extract the product several times, to sacrifice yield for purity. Just be very clean. Whatever method you use should remove salts and proteins, which are the major contaminants. I won't go too much into how ...


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This is a question which is not easy to answer, especially the 50.000bp number (which I haven't found anywhere in there literature). However, I found some evidence, partly derived from plant and mammal artificial chromosomes (references 1 and 2), partly from the original publication from Murray and colleagues (reference 3). The problems with small ...


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PCR ideally doubles the number of amplified DNA molecules in each cycle. So after the first step you have 10 molecules, after the second 20, the third 50 and so on. The formula for the calculation is: n × 2cycles = number of molecules n is the number of molecules you start your PCR with, cycles is the number of cycles used. In your case this would be: 5 ...


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The "substance" is hydrogen bonds (H-bonds), or rather the potential to form them. Each of the unpaired A/T bases in the sticky ends have the potential to form 2 H-bonds with a complementary T/A, and each of the unpaired G/C bases have the potential to form 3 H-bonds with a complementary C/G. From the perspective of a biophysicist, H-bonds are often thought ...


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The sticky ends are sticky because they have complementary bases. Typically used restriction enzymes cut the two complementary DNA strands at different spots, generating 'overhang', or sticky ends: These overhangs allow for perfect base pairing (C with G, A with T), which is the result of hydrogen bonding. Just like water molecules show strong affinity to ...


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What are sticky ends. There is no substance that is attached making the DNA ends "sticky". What has actually happened is an overhang of at least a few nucleotides. Blunt ends are another kind of cut, but have no overhanging residues. Why are sticky ends sticky? Restriction enzymes usually cut these ends deliberately so that a four nucleotides are ...


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I am sure you have done it; just a note to others: do a PCR screen to ascertain that the plasmid is there. For minipreps you generally do not need a starter culture. If you have screened your clones and now just want to amplify and keep the plasmid for cloning purposes then go for a maxiprep with 200-400ml cultures. Do not overgrow the cells, your ...


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I'm no expert at this but I don't think you need a Turing machine to achieve this, at least for DNA, since in conventional sense (not including carcinogenic factors such as UV) the most probable stage in which a DNA mutation can happen is during DNA replication so DNA polymerase engages in proofread to ensure accurate DNA replication, and then the DNA can ...


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Genome-wide variation from one human being to another can be up to 0.5% (99.5% similarity) Chimpanzees are 96% to 98% similar to humans, depending on how it is calculated. (http://genome.wellcome.ac.uk/doc_WTD020730.html) Cats have 90% of homologous genes with humans, 82% with dogs, 80% with cows, 79% with chimpanzees, 69% with rats and 67% with mice. ...


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There is no difference in base pairing between different kinds of organisms. Humans, animals and bacteria all share the same fundamental mechanisms as they all use DNA. Which bases can pair is determined by the chemistry of the individual bases. The bases in DNA form the following hydrogen bonds when they are paired: If you would try to combine other ...


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The problem with answering your question accurately is, one, the absorption of a phtoton is a quantum mechanical phenomenon with almost a random chance of happening, and two, once absorbed, a lot of photophysical processes can occur, mutation being only a small part of the available options. Thus, to quantify the threshold amount of radiation for mutation ...



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