Deoxyribonucleic acid primary structure

Nucleic acids are acidic substances present m the nuclei of cells and were known long before anyone suspected they were the primary substances involved m the storage transmission and processing of genetic information There are two kinds of nucleic acids ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) Both are complicated biopolymers based on three structural units a carbohydrate a phosphate ester linkage between carbohydrates and a heterocyclic aromatic compound The heterocyclic aro matic compounds are referred to as purine and pyrimidine bases We 11 begin with them and follow the structural thread... 

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... 

Ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) are both biopolymers of nucleic acids, but they have minor structural differences that lead to major functional differences. All living cells use DNA as the primary genetic material that is passed from one generation to another. DNA directs and controls the synthesis of RNA, which serves as a short-lived copy of part of the much larger DNA molecule. Then, the cellular machinery translates the nucleotide sequence of the RNA molecule into a sequence of amino acids needed to make a protein. 

Ribonucleic Acid. RNA yeast nucleic acid. Polynucleotide directly involved in protein synthesis found in both the nucleus and the cytoplasm oi cells. Description of components of RNA see Nucleic Acids. The Four primary nucleosides are adenosine, guanosine, cytidine and uridine minor nucleosides are also found. The nucleosides are linked by phosphate diester bonds from the 3 -hydroxyl of one D -ribose to the 5 -hydroxyl of the next. The secondary structure of RNA is that of an incompletely Organized single-stranded polynucleotide consisting of some areas with helical structure alternating with non helical lengths. Compere Deoxyribonucleic Acid (DNA). Structure Brown,... 

How do DNA and RNA differ DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) are the two kinds of nucleic acids. DNA contains the sugar deoxyribose, but RNA has ribose in the same position. The difference in the sugars gives rise to differences in their secondary and tertiary structures. The primary structure of nucleic acids is the order of bases in the polynucleotide sequence, and the secondary structure is the three-dimensional conformation of the backbone. The tertiary structure is specifically the supercoUing of the molecule. 

Marshall LE, Graham DR, Reich KA, Sigman DS. Cleavage of deoxyribonucleic acid by the l,10-phenanthrohne-cuprous complex. Hydrogen peroxide requirement and primary and secondary structure specificity. Biochemistry. 1981 20 244-250. 

Deoxyribonucleic acid (DNA), on the other heind, may be thought of as a simpler host polymer in terms of primary and higher order structures.3 So it is interesting to compare its binding behavior with those of another class of polymers, since the interactions of DNA with various kinds of ligands are biologically and medically important. l ... 

Deoxyribonucleic acids consist of a backbone of alternating units of deoxyribose and phosphate in which the 3 -hydroxyl of one deoxyribose unit is joined by a phosphodiester bond to the 5 -hydroxyl of another deoxyribose unit (Figure 20.5). This pentose—phosphodiester backbone is constant throughout an entire DNA molecule. A heterocyclic aromatic amine base—adenine, guanine, thymine, or cytosine—is bonded to each deoxyribose unit by a j8-Atglycosidic bond. The primary structure of a DNA molecule is the order of heterocyclic bases along the pentose-phosphodiester backbone. The sequence of bases is read from the 5 end to the 3 end. 

Proteomics is the study of proteins their structure and function and their interactions with other proteins. Proteins are made from the primary sequence of deoxyribonucleic acid (DNA), which is then transcribed into a messenger RNA (mRNA) molecule, which in turn is translated into polypeptide chains that will form a three-dimensional functional protein product. The study of proteins is complicated— more so than the study of genomics— because of the complexity of modifications that take place for the DNA sequence to become a protein product and because the proteome changes from cell to cell and at different time periods in a cell or organism s Ufe. 

The primary structure of deoxyribonucleic acid (DNA) consists of units of... 

The specific sequence of amino acids of which the polypeptide is made is called the primary structure, and its formation is controlled by that piece of deoxyribonucleic acid (DNA) (Chapter 14) that dictates, through the genetic code vide infra), which amino acid the machinery (e.g., the ribosome [about which more will be said later]) that joins them is to use and in what order the amino acids are to be combined. In principle, the ribosome could build a linear chain from right to left or left to right, so, by convention, peptides are written with the N-terminal amino acid to the left and the carboxylate terminus on the right. 

The information which specifies the amino-acid sequence of a protein is stored in the nucleotide sequence of the double helix of deoxyribonucleic acid (DNA). The transcription of sections of this information into ribonucleic acid (RNA) is catalysed by RNA polymerases. These enzymes not only control the synthesis of RNA but also recognize stop and start signals on the DNA. The start signals are complex and may be blocked by repressor molecules which inhibit the transcription process. Once synthesized, the (messenger) RNA is processed and exported to ribosomes where its nucleotide sequence is translated into protein. Triplets of three nucleotides (codons) in the messenger RNA each specify (encode) one amino acid. The linear sequence of nucleotides in the messenger RNA thus specifies the sequence of amino acids in the protein whose primary structure will therefore correspond directly to the sequence of nucleotides in the DNA. 

Deoxyribonucleic Acids as Genetic Material. The substance that makes up the hereditary factors or genes is deoxyribonucleic acid. In general, the current concept is that for each individual gene there is as the chemical equivalent an appropriate DNA characterized by a definite base sequence. The information carried by the gene and finally expressed as a particular character consists in the sequence of the bases. The base sequence in turn determines the primary structure, i.e., the sequence of amino acids, of proteins. There is a direct correlation A certain group of bases of the DNA stands for a certain amino acid in the final protein. 

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