Theoretical backgroundNucleic acids are polymeric compounds-organic macromolecules consistingfrom building blocks called nucleotides. Each nucleotide consists of apentozi, a nitrogenous base and a phosphate group.There are two main types of nucleic acids? the RNA (Ribonucleic acid) and the DNA(deoxyribonoykleϊko acid). DNA consists of deoxyribonoykeotidia To have as pentozithe Deoxyribose and nitrogenous bases adenine (a), thymine (t), cytosine (C) and theguanine (G).DNA molecules are almost always in the form of chain plied withopposite direction which restrained at the site with the links betweenbases, forming a clockwise spiral.The DNA in eukaryotes is linear and is protectedwithin the nucleus of the cell. Because the length is too long (in humans is 2measures within each cell) paketaretai with the help of proteins, most importantwhich is the histones, giving characteristic structures, the chromatin filament orchromosomes.There are three basic steps in extracting DNA from raw material (living cells):1. The cells must be resolved (to break) and released the kernels,which must be broken. For the solution of the membranes we usedetergent which has the ability to connect with the phospholipids ofmembranes and apodiatasei.2. The DNA must be freed from the proteins with which it isbound and syswmatwthei. The breakdown of proteins is achieved with theuse specific proteolytic enzymes such as proteinase k and the pepipsi. A kindvegetable pepsin is papain which exists in papaya fruit juice. Eventhe wet contact lenses (1-2 drops) contains proteases, which Cleave theproteins. The agglomeration of DNA can be made with the use of salt (NaCl). ). Thepositive metal ions of salt neutralize the negative phosphate groupsof DNA, resulting in DNA molecules to exhibit the tendency toaccumulate together.3. The DNA must be separated from the other components of the cell. For theseparation of DNA from the remaining components of the cell extractuse ethanol. In water, the DNA is soluble. When in ethanol,unrolled and precipitated, leaving behind the other cellular components, which are notsoluble in ethanol. Only DNA can form fibers on ethanol, as theRNA forms a much smaller pieces and the proteins remain in the aqueous phase with the pulmonary xme
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