Deoxyribonucleic acid molecular weights

Values found for the molecular weight of deoxyribonucleic acids also vary considerably, but probably lie between 1.0 X 106 and 4.4 X 106. Various difficulties encountered in making such measurements have been discussed by Jordan,244 and it is probable that more reliable information will be obtained only when the behavior of polyelectrolytes in general is better understood. Certain of the techniques used are useful in detecting differences between different nucleic-acid preparations, but the discrepancies between the values given by different methods of measurement appear to vary with the degree of polymerization.246... 

Harry Compton Crick, American scientist and Nobelisi (1962), proposed that ihe molecular structure of DNA is composed of deoxyribonucleic acid and proteins lhistones and high-molecular-weight proteins . These researchers proposed that the molecular structure of DNA is a double spiral helical chain. James H. White. American mathematician, shared the 1962 Nobel Prize. 

A typical molecular analysis of various micro-organisms is shown in Table 5.9U ) Most of the elemental composition of cells is found in three basic types of materials—proteins, nucleic acids and lipids. In Table 5.10, the molecular composi-tion of a bacterium is shown in more detail. Water is the major component of the cell and accounts for 80-90 per cent of the total weight, whilst proteins form the next most abundant group of materials and these have both structural and functional properties. Most of the protein present will be in the form of enzymes. Nucleic acids are found in various forms—ribonucleic acid (RNA) and deoxyribonucleic acid (DNA). Their primary function is the storage, transmission and... 

The two major classes of nucleic acids are ribonucleic acids (RNA) and deoxyribonucleic acids (DNA). In a typical cell, DNA is found primarily in the nucleus, where it carries the permanent genetic code. The molecules of DNA are huge, with molecular weights up to 50 billion. When the cell divides, DNA replicates to form two copies for the daughter cells. DNA is relatively stable, providing a medium for transmission of genetic information from one generation to the next. 

The substance that stores and transmits the genetic information is a polymer called deoxyribonucleic acid (DNA), a huge molecule with a molecular weight as high as several billion grams per mole. Together with other similar nucleic acids called the ribonucleic acids (RNA), DNA is also responsible for the synthesis of the various proteins needed by the cell to carry out its life... 

In deoxyribonucleic acid (DNA) the carbohydrate is 2-deoxy-D-ribose, while in ribonucleic acid (RNA) the carbohydrate residue is ribose. Three types of RNA were recognized, and they can be messenger RNA (mRNA), transfer RNA (tRNA), or ribosomal RNA (rRNA), which is the most abundant in cells. Values between 10 and 10 Dalton have been reported for the molecular weight of DNA, and the molecular weight is about 10 for rRNA, 10 for mRNA, and lOMor rRNA. The simplified structures of DNA and RNA are the following ... 

A gene is a set of segments of nucleic acid. A nucleic acid is a complex, high molecular weight biochemical macromolecule composed of nucleotide chains that convey genetic information. The most common nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). 

Nucleic acids are high-molecular-weight, mixed polymers of mononucleotides, in which chains are formed by monophosphate links between the 5 -position of one nucleoside and the 3 -position of the next. The backbone of the chain is thus composed of alternating phosphates and sugars, to which purine and pyrimidine bases are attached at regular intervals. The polymer is known as ribonucleic acid (RNA) when the sugar is ribose, and deoxyribonucleic acid (DNA) when the sugar is 2-deoxyribose. 

Matrix-assisted laser desorption ionization is a very powerful technique for the analysis of synthetics and biopolymers, and it has completely replaced former techniques such as fast atom bombardment (FAB). In most cases, singly charged ions are predominantly detected while very little fragmentation or multiply charged ions are observed. MALDI is commonly used for the analysis of high-molecular-weight compounds such as peptides and proteins (Rappsilber et al., 2003), synthetic polymers (Nielen, 1999), deoxyribonucleic acid (DNA) (Gut, 2004), and lipids (Schiller et al., 2004). 

Gel electrophoresis is an important technique for separating high-molecular-weight (MW) biological molecules, such as deoxyribonucleic acid (DNA), lipoproteins, immunoglobulins, and... 

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