Ribonucleic acid molecular weights

The same research group proved the applicability of PEO-silicas to the separation of ribonucleic acids and studied how the log k vs m slopes are affected by the molecular weight of polyethylene oxide, the type of salt used in eluent... 

As has been emphasized previously, whereas some early measurements indicated a molecular weight of the order of 1000 for the ribonucleic acid of yeast, it is now known that the molecule is considerably larger than this. To give accurate values for the molecular weights of ribonucleic acids is however, difficult, since not only do the estimates vary with the method of preparation, but also with the technique used for making the measure-... 

Because of their relatively low molecular weight (70 to 90 nucleotide residues), transfer ribonucleic acids are of special interest for 13C NMR investigations [769, 778, 782-784] of nucleic acids. Using a tube of 20 mm o.d., a sample of thermally denatured yeast... 

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... 

A. C. Peacock and C. W. Dingman, Biochemistry, 7 688-674 (1968). Molecular Weight Estimation and Separation of Ribonucleic Acid by Electrophoresis in Agarose-Acrylamide Composite Gels. 

U. E. Loening, Biochem. J., 102 251 (1967). Fractionation of High-Molecular Weight Ribonucleic Acid by Polyacrylamide-Gel Electrophoresis. 

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 ... 

As implied in the Introduction, both proteins and (deoxy)ribonucleic acids can be viewed as ideal tyligomers—that is, the archetypal biological examples of discrete, high molecular weight macromolecules of mixed sequences with compact solution conformations assembled from many subunits of secondary structure. In our assessment of the literature, we have organized foldamer systems into four... 

Biopolymers are either synthesized by template-dependent or template-independent enzymatic processes. For the synthesis of nucleic acids and proteins a template is required, whereas all other polymers are synthesized by template-independent processes. The templates for nucleic acids are desoxyribonucleic acids or ribonucleic acids depending on the type of nucleic acid synthesized. For proteins, the template is messenger ribonucleic acid (mRNA). This has different impacts on the structure and on the molecular weights (MWs) of the polymers. Although both nucleic acids and proteins are copolymers with each type consisting of 4 or 22 different constituents, respectively, the distribution of the constituents is absolutely defined by the matrix and is not random. Furthermore, each representative of the two polymers has a defined MW. Polymers synthesized in template-dependent processes are monodisperse. All this is different in polymers synthesized by template-independent processes first of all, these polymers are polydisperse secondly, if these polymers are copolymers, the distribution of the constituents is more or less fully random. 

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. 

This chapter briefly describes the synthesis of a variety of cationic polymers by LRP and their applications as deojqnribonucleic acid (DNA) and small interfering ribonucleic acid (siRNA) delivery agents. The polymers of different shapes, architectures and molecular weights will be compared for their gene expression profiles. Moreover, the S3mthesis of polymeric... 

Morell, P., I. Smith, D. Dubnau, and J. Marmur. 1967. Isolation and characterization of low molecular weight ribonucleic acid species from Badllus subtilis. Biochemistry, 6 258-265. 

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