Sugar component, nucleic acids

Weith, H.L., Wiebers, J.L., and Gilham, P.T. (1970) Synthesis of cellulose derivatives containing the dihy-droxyboryl group and a study of their capacity to form specific complexes with sugars and nucleic acid components. Biochemistry 9, 4396-4401. 

Catterall H, Davies MJ, Gilbert BC (1992) An EPR study of the transfer of radical-induced damage from the base to sugar in nucleic acid components relevance to the occurrence of strand-breakage. J Chem Soc Perkin Trans 2 1379-1385... 

The major classes of organic compounds common to living systems are lipids pro terns nucleic acids and carbohydrates Carbohydrates are very familiar to us— we call many of them sugars They make up a substantial portion of the food we eat and provide most of the energy that keeps the human engine running Carbohy drates are structural components of the walls of plant cells and the wood of trees Genetic information is stored and transferred by way of nucleic acids specialized derivatives of carbohydrates which we 11 examine m more detail m Chapter 28... 

Nucleic Acids. Phosphoms is an essential component of nucleic acids, polymers consisting of chains of nucleosides, a sugar plus a nitrogenous base, and joined by phosphate groups (43,44). In ribonucleic acid (RNA), the sugar is D-ribose in deoxyribonucleic acids (DNA), the sugar is 2-deoxy-D-ribose. 

Nucleic Acids. Nucleic acids are polynucleotides that is, they are condensation polymers of nucleotide monomers. A nucleotide is a three-component system, ie, a combination of a sugar, a phosphate, and a nitrogenous base residue. Adenosine monophosphate is an example ... 

As is well-known, nucleic acids consist of a polymeric chain of monotonously reiterating molecules of phosphoric acid and a sugar. In ribonucleic acid, the sugar component is represented by n-ribose, in deoxyribonucleic acid by D-2-deoxyribose. To this chain pyrimidine and purine derivatives are bound at the sugar moieties, these derivatives being conventionally, even if inaccurately, termed as pyrimidine and purine bases. The bases in question are uracil (in ribonucleic acids) or thymine (in deoxyribonucleic acids), cytosine, adenine, guanine, in some cases 5-methylcytosine and 5-hydroxymethylcyto-sine. In addition to these, a number of the so-called odd bases occurring in small amounts in some ribonucleic acid fractions have been isolated. 

The nucleic acids, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), which carry embedded in their complex molecules the genetic information that characterizes every organism, are found in virtually all living cells. Their molecules are very large and complex biopolymers made up basically of monomeric units known as nucleotides. Thus DNA and RNA are said to be polynucleotides. The nucleotides are made up of three bonded (linked) components a sugar, a nitrogenous base, and one or more phosphate groups ... 

Oligonucleotides with modified sugar components are another alternative to PNAs work in this direction was begun by Albert Eschenmoser, a famous synthetic chemist who was interested in the question as to why nature chose certain biomolecules for the processes of life and not others (Eschenmoser, 1991). This group carried out studies on the sugar components of the nucleic acids, in order to find out why D-ribose was used rather than another sugar. 

In the two nucleic acids, the sugar component consists solely of D-ribose or D-deoxyribose. 

Figure 1.40 The two forms of sugar residues commonly found in nucleic acids. 3-D-Ribose is the sugar constituent of RNA, while p-D-2-deoxyribose is a component of DNA.

Tipson devoted most of his years in Levene s laboratory accomplishing seminal work on the components of nucleic acids. To determine the ring forms of the ribose component of the ribonucleosides he applied Haworth s methylation technique and established the furanoid structure for the sugar in adenosine, guanosine, uridine, and thymidine. He showed that formation of a monotrityl ether is not a reliable proof for the presence of a primary alcohol group in a nucleoside, whereas a tosyl ester that is readily displaced by iodide affords clear evidence that the ester is at the 5-position of the pentofuranose. Acetonation of ribonucleosides was shown to give the 2, 3 -C -isopropyl-idene derivatives, which were to become extensively used in nucleoside and nucleotide chemistry, and were utilized by Tipson in the first chemical preparation of a ribonucleotide, inosinic acid. 

Over thirty publications resulted from Tipson s work in Levene s laboratory. Along with the work on nucleic acid components, he also studied the structures of gum arabic and other plant gums, and conducted a range of synthetic investigations on sugars, with particular emphasis on uronic acids and 5-carbon ketoses. His 1939 observation that acetylated glycosyl halides... 

By the second half of the nineteenth century German chemists had established a dominant position in analytical and synthetic organic chemistry. Various simple sugars and aminoacids were being isolated and characterized, as well as more complex plant products. Studies on the composition of blood and the properties of hemoglobin were also well under way. The composition of lipid-rich components and the order of the different units within complex macromolecules, such as proteins and nucleic acids, could not however be resolved by techniques then available. 

Nucleic acids (DNA and RNA) are assembled liom nucleotides, which consist of three components a nitrogenous base, a five-carbon sugar (pentose), and phosphate. 

The nucleic acids play a central role in the storage and expression of genetic information (see p. 236). They are divided into two major classes deoxyribonucleic acid (DNA) functions solely in information storage, while ribonucleic acids (RNAs) are involved in most steps of gene expression and protein biosynthesis. All nucleic acids are made up from nucleotide components, which in turn consist of a base, a sugar, and a phosphate residue. DNA and RNA differ from one another in the type of the sugar and in one of the bases that they contain. 

When a nucleic acid base is N-glycosidically linked to ribose or 2-deoxyribose (see p.38), it yields a nucleoside. The nucleoside adenosine (abbreviation A) is formed in this way from adenine and ribose, for example. The corresponding derivatives of the other bases are called guanosine (G), uridine (U), thymidine (T) and cytidine (C). When the sugar component is 2-deoxyribose, the product is a deoxyribonucleoside—e. g., 2 -deoxyadeno-... 

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