Nucleotide Phosphate ester nucleoside

Nucleotides are phosphate esters of nucleosides, formed at the CH OH group of the sugar. 

The purine and pyrimidine ring compounds found in nucleic acids are known as "bases," even though some of them have almost no basic character. Nucleosides are the N-glycosyl derivatives of the bases with ribose or 2-deoxyribose. Tire nucleotides are phosphate esters of nucleosides. Similar names are applied to related compounds such as adenosine triphosphate (ATP) that are not present in DNA or RNA. The names of the principal nucleotides from which the nucleic acids are formed are given in Table 5-1. The... 

A nucleotide is a phosphate ester of a nucleoside. The hydroxyl group at the C5 position of the pentose is the most common site of esterification. The nucleotides of adenosine are ATP, ADP, and AMP (Section 15-5F). 

The DNA sugar is 2-deoxy-D-ribose. The four heterocyclic bases in DNA are cytosine, thymine, adenine, and guanine. The first two bases are pyrimidines, and the latter two are purines. In nucleosides, the bases are attached to the anomeric carbon (C-1) of the sugar as p-N-glycosides. In nucleotides, the hydroxyl group (-OH) at C-3 or C-5 of the sugar is present as a phosphate ester. 

The term nucleoside was originally proposed by Levene and Jacobs in 1909 for the carbohydrate derivatives of purines (and, later, of pyrimidines) isolated from the alkaline hydrolyzates of yeast nucleic acid. The phosphate esters of nucleosides are the nucleotides, which, in polymerized forms, constitute the nucleic acids of all cells.2 The sugar moieties of nucleosides derived from the nucleic acids have been shown, thus far, to be either D-ribose or 2-deoxy-D-eri/fAro-pentose ( 2-deoxy-D-ribose ). The ribo-nucleosides are constituents of ribonucleic acids, which occur mainly in the cell cytoplasm whereas 2-deoxyribo -nucleosides are components of deoxypentonucleic acids, which are localized in the cell nucleus.3 The nucleic acids are not limited (in occurrence) to cellular components. They have also been found to be important constituents of plant and animal viruses. 

Nucleoside + phosphate yields phosphate ester nucleotide. 

Nucleotides A nucleotide is a phosphate ester of a nucleoside. It consists of a phosphate... 

Formamide is itself hydrolyzed by water, meaning that it persists only in a relatively dry environment, such as a desert. Desert environments recently proposed as being potential sites for the prebiotic synthesis of ribose18 may hold formamide as well. Since formamide boils at —400 K, a mixture of formamide and water, if placed in the desert, would lose its water over time and end up as a pool of formamide. Within this pool, many syntheses are thermodynamically favorable polypeptides from amino acids, nucleosides from sugars and bases, nucleotides from nucleosides and inorganic phosphate, and RNA from nucleotides. Indeed, phosphate esters are also spontaneously synthesized. This includes ATP (from ADP and inorganic phosphate), nucleosides (from ribose borates and nucleobases), peptides (from amino acids), and others.19-21... 

Nucleic acids are unquestionably top level molecules because they store our genetic information. They are polymers whose building blocks (monomers) are the nucleotides, themselves made of three parts—a heterocyclic base, a sugar, and a phosphate ester. A nucleoside lacks the phosphate. In the example alongside, adenine is the base (black), adenosine is the nucleoside (base and sugar), and the nucleotide is the whole molecule (base + sugar + phosphate). 

Nucleosides corisist of a heterocyclic aglygone attached via a glycosyl linkage to a carbohydrate moiety. Most biological nucleosides are A -glycosyl derivatives of the pentose sugars o-ribose or 2 -deoxy-o-ribose. Table I lists some of the common nucleosides. Nucleotides are phosphate esters of the nucleosides. Table II lists some of the common nucleotides. 

The nomenclature of nucleotides and their constituent units was presented earlier (Section 5.1.2). Recall that a nucleoside consists of a purine or pyrimidine base linked to a sugar and that a nucleotide is a phosphate ester of a nucleoside. The names of the major bases of RNA and DNA, and of their nucleoside and nucleotide derivatives, are... 

Nucleosides (e. g. adenosine, cytidine, guanosine, pyrimidine, thymidine, uridine) consist of a nitrogenous purine or pyrimidine base linked to a 5-carbon sugar (ribose or deoxyribose). Nucleotides (adenine, cytosine, guanine, thymine, uracil), the phosphate esters of nucleotides, form the basis of RNA and DNA. As infectious viral nucleic acids, they are capable of penetrating the cells and using available enzyme systems for replication. 

Nucleosides and nucleotides are combinations of a base with a sugar. A nucleoside is an N-glycoside formed between a base and a sugar (usually ribose or deoxyribose). A nucleotide is a phosphate ester of a nucleoside. DNA nucleotides are more stable to acid hydrolysis of the glycosidic bond, which is one reason tfrat DNA has superceded RNA as the main genetic storage molecule it is less prone to mutation. 

Phosphate esters show important thermal susceptibility (Fig. 1). Dialkyl phosphates, such as those found in nucleic acids (Fig. 2), decompose with the initial loss of one alkyl group, the concomitant transfer of protons, followed by the elimination of the second alkyl group and the subsequent loss of water. This thermal instability of phosphoesters has been used in the analysis of nucleic acids. Thus the pyrolysis that usually precedes the recording of a mass spectrum permits cleavage of the polymeric phosphoesters (nucleic acids), followed by phosphate extrusions, producing nucleotides or simple nucleosides as fragment ions. 

A base linked to a sugar is called a nucleoside a base linked to a sugar linked to a phosphate is called a nucleotide or a nucleoside phosphate. The nucleotides in nucleic acids are joined to one another by a second phos-phodiester bond that joins the 5 -phosphate of one nucleotide to the 3 -OH group of the adjacent nucleotide. Such a doubly esterified phosphate is called aphosphodi-ester group (Figure 23-2). 

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