Nucleic acids nucleotide subunits

In addition to their roles as the subunits of nucleic acids, nucleotides have a variety of other functions in every cell as energy carriers, components of enzyme cofactors, and chemical messengers. 

Polynucleotide a polymer formed from nucleotide subunits a synon3m for nucleic acid. Polypeptide a synonym for protein. 

Anand R, lindstrom J Nucleotide sequence of the human nicotinic acetylchohne receptor PZ subunit. Nucleic Acids Res 18 4272-4278, 1990 Ananth J, Solyom L, Bryhtwick S, et al Clomipramine therapy for obsessive compulsive neurosis. Am J Psychiatry 136 700-720, 1979 Ananth J, Pecknold JC, van den Steen N, et al Double-bhnd study of clomipramine and amitriptyline on obsessive neurosis. Prog Neuropsychopharmacol 5 225-262, 1981... 

Mild hydrolysis of nucleic acids yields the monomeric nucleotides. Subsequent complete hydrolysis of a nucleotide furnishes three structural subunits ... 

Separating Biomolecules In studying a particular biomolecule (a protein, nucleic acid, carbohydrate, or lipid) in the laboratory, the biochemist first needs to separate it from other biomolecules in the sample—that is, to purify it. Specific purification techniques are described later in the text. However, by looking at the monomeric subunits of a biomolecule, you should have some ideas about the characteristics of the molecule that would allow you to separate it from other molecules. For example, how would you separate (a) amino acids from fatty acids and (b) nucleotides from glucose ... 

Just as the amino acids, sugars, and nucleotides are the building blocks for formation of proteins, polysaccharides, and nucleic acids, these three kinds of macromolecule are the units from which larger subcellular structures are assembled. Fibers, microtubules, virus "coats," and small symmetric groups of subunits in oligomeric proteins all result from the packing of macromolecules in well-defined ways, something that is often called quaternary structure. 

Ribosomal RNA (rRNA) Ribosomes, which are about two thirds nucleic acid and about one third protein, constitute about 90% of a cell s RNA. A ribosome is made up of two subunits. The larger one contains two rRNAs, one with 122 nucleotides and the other with 2923 the smaller subunit contains one rRNA which has 1500 nucleotides. 

The subunits of nucleotides are finked together to form a long polymer chain in nucleic acids. The linkages are formed between the phosphate group of one subunit and the sugar group of the next. This matrix forms a sugar-phosphate backbone to the molecule of nucleic acid. 

Nucleic acid. A polymer of nucleotide subunits linked by phosphate bridges the nucleotides contain purine or pyrimidine bonded to ribose or deoxyribose (see chemical glossary). Nucleic acids form the basis for the genetic code in all living things. 

Therefore, enzyme-catalyzed reactions in which irreversibility is important take place by one of the mechanisms that form pyrophosphate as a product (attack on the a- or i8-phosphorus of ATP). For example, both the reaction that links nucleotide subunits to form nucleic acids (Section 27.7) and the reaction that binds an amino acid to a tRNA (the first step in translating RNA into a protein Section 27.12) involve nucleophilic attack on the a-phosphoms of ATP. 

Jamet, E., C. Fargeas, A. Durr, and J. Fleck Nucleotide sequences of two genes encoding the small subunit of RUBISCO in Nicotians sylvestris Nucleic Acids Res. 

The ultimate basis for controlling biochemical reactions is the genetic information stored in the cell s DNA. This information is expressed in a regulated fashion, so that the enzymes responsible for carrying out the cell s chemical reactions are released in response to the needs of the cell for energy production, replication, and so forth. The information is composed of long sequences of subunits, where each subunit is one of the four nucleotides that make up the nucleic acid. 

Nucleic acids, both DNA and RNA, are polynucleotides (Fig. 3-36). They are polymers that have nucleotides as their repeating subunits. The nucleotides are joined to one another through phosphodiester bonds between the C-3 of one nucleotide and the C-5 of the next. This linkage is repeated many times to huild up a large structure (chain or strand) that contains hundreds to millions of nucleotides within the single macromolecule. Thus the sugar residues are each decorated hy a nucleohase that is either a purine or a pyrimidine. It is these bases that make up a sequence that codes for a particular cellular outcome, be it a protein or a polynucleotide s structural element such as a rihosome (Chaps. 7 and 8). 

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