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I suggest you to try Recursive Directional Ligation. It is meant to do exactly what you are aiming for, i.e. to "polymerize" short DNAs into a longer one. You can find the protocol here http://pubs.acs.org/doi/abs/10.1021/bm015630n


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The scope of this question is too wide to be answered on Biology SE. However I will give you very brief answers to your questions (as I have rephrased them) and point you towards some sources of basic information on the Internet. After reading these you may wish to return with more specific questions. I have also briefly summarized some of the problems which ...


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the OH group in the two position acts a as a nucleophilic catalyst for the cleavage of RNA or of DNA if it had such a group. Since DNA needs to stay intact throughout the life of a cell it would be disastrous if it were cleaved because of the 2'OH group. RNA on the other hand is rapidly cleaved as needed by the cell without detrimental consequences to the ...


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A Reverse Translatase, if it was discovered, would be the biggest discovery in biology (maybe in science generally?) in the last 30 years. We would LOVE to be able to treat proteins as strings of information in the same way as we do nucleotides. But there are good theoretical reasons why it's unlikely. As already mentioned above - the RNA->protein map isn't ...


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"Reverse translation" Translation is the process by which an mRNA is "translated" into a protein. It is impossible to get the exact DNA sequence from the protein sequence because a large number different DNA strands could code for the exact same proteins. In other words, there is a loss of information in the translation process. See codon redundancy and I ...


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Mutations are not performed targeting a specific new phenotype. There is no way an organism can "know" the impact of a specific future mutation anyway. A mutation is just a mistake in the replication process. As a consequence the majority of mutations are deleterious and only a handful of mutations are beneficial. It is true though that the mutation rate ...


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The fact that there is no inter-strand cross-linking between different double strands might be just because the cross-linker cannot bridge the distance between amines of different bases on different double strands. The formaldehyde based linking of nucleobases has been described by Chaw et al. (1980) where formaldehyde bridged a gap of app. 3 angstroms (2x ...


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If you mean to say why DNA is in the form of chromosomes, then obviously answer is simple: For Compression and Packaging - Around 2metre long DNA must be compressed (at an unbelievably high ratio) to let it fit in the tiny nucleus (order of micrometers)


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(For the direct answer to your question skip to the end!) Genetic linkage can affect the spread of other genes. The degree of linkage, affected by the rate of recombination between the point (nucleotide, gene etc.) directly under selection and the other point. If the rate of recombination between to given points is low then linkage between them is high and ...


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Genetic hitchhiking / genetic draft From wikipedia Genetic hitchhiking, also called genetic draft or the hitchhiking effect, is when an allele changes frequency not because it itself is under natural selection, but because it is near another gene on the same chromosome that is undergoing a selective sweep. The term "selective sweep" is used improperly ...


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One option is to use SPRI beads, like those sold by Ampure (Ampure XP beads) to separate DNA fragments by size. By adjusting the ratio of beads to sample, you can selectively bind fragments of certain lengths by excluding those of other lengths, as seen in the following image: From this image, you might try using a beads-to-sample ratio of 0.7 to exclude ...


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In my mind, gel separation (using a fairly high percentage gel to separate the bands as much as possible) and manual excision is by far the best option. The problem with molecular weight cutoff filters is that the value they give (5000 Da, for example) is an average pore size, it is not exact. Therefore, any attempt to separate 270 bp from 170 bp oligos will ...



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