Deoxyribonucleic acid, nucleotide sequence

This is a CE analog of conventional zone gel electrophoresis for the separation of macromolecules based on size. The capillary is filled with a porous polymer gel, and molecular sieving occurs as the molecules move through the gel, that is, separation is based on both electrophoretic mobility and molecular size. Very high resolution is achieved. The trend is to fill the capillary with a liquid gel matrix (pumpable gel solutions, such as deriyatized celluloses dissolved in the run buffer). This allows replacement of the gel in the capillary to eliminate contamination problems from the sample matrix that occurs with fixed gels.. This technique is widely used for separation of nucleotides in deoxyribonucleic acid (DNA) sequencing (Chapter 25). 

The Nucleotide Sequence in Deoxypentosenucleic Acids. Part IV. The Deoxyribonucleic Acid of Mycobacterium phlei," A. S. Jones, M. Stacey, and B. E. Watson, /. Chem. Soc., (1957) 2454-2459. 

Since the discovery of the double hehcal structure of deoxyribonucleic acid (DNA) by Watson and Crick in 1953 [1], there has been considerable belief that the canonical right-handed B-DNA may adopt a wide range of different conformations depending on the nucleotide sequences and environmental conditions. This speculation turned out to be a reahty [2-10]. hi hving systems, the conformational flexibility of DNA resides primarily in the polymorphs of the DNA double hehx (including right-handed and left-handed double hehcal DNA) and occurs under various environmental conditions [4j. The main family of DNA forms identified, based on circular dichroic and... 

DNA (deoxyribonucleic acid) A double-stranded molecule held together by weak bonds between base pairs of nucleotides that encodes genetic information. The base sequence of each single strand can be deduced from that of its partner since base pairs form only between the bases A and T and between G and C. 

All cells in living organisms contain the large nucleic acid molecules of ribonucleic acid (RNA) and deoxyribonucleic acid (DNA). Both these molecules are polymers of nucleotides. DNA is found in chromosomes, and genes are unique sequences of DNA nucleotides. The genes contain the inheritable information which together with RNA directs the synthesis of all the cell s proteins. 

A second major area of biochemical importance concerns study of nucleotide polymerization to produce ribonucleic acids (RNA) and deoxyribonucleic acids (DNA). Genes, the basis for inherited characteristics, are contained in DNA double-helical sections incorporated into coiled and supercoiled DNA structures. Genomics, the study of the total genetic assemblage of any species, is now a well-known topic to all, especially with the announcement of the sequencing of the human genome in 2001. More information on this topic is given in Section 2.3.6. 

Three major components in the transmission of genetic information are deoxyribonucleic acids (DNA), ribonucleic acids (RNA), and proteins. The genetic code expressed through DNA ultimately determines which proteins a cell will produce. Coiled and supercoiled DNA molecules contain numerous sequences of nucleotides that may be transcribed as RNAs and translated to many different proteins. DNA molecules also contain long sequences of nucleotides not coding for protein and whose purpose is not completely understood. A gene is a specific sequence of DNA that encodes a sequence of messenger... 

Nucleotides have a variety of roles in cellular metabolism. They are the energy currency in metabolic transactions, the essential chemical links in the response of cells to hormones and other extracellular stimuli, and the structural components of an array of enzyme cofactors and metabolic intermediates. And, last but certainly not least, they are the constituents of nucleic acids deoxyribonucleic acid (DNA) and ribonucleic acid (ENA), the molecular repositories of genetic information. The structure of every protein, and ultimately of every biomolecule and cellular component, is a product of information programmed into the nucleotide sequence of a cell s nucleic acids. The ability to store and transmit genetic information from one generation to the next is a fundamental condition for life. 

Deoxyribonucleic acid A nucleic acid containing a deoxygenated ribose sugar, having a double helical structure, and carrying genetic code in the nucleotide sequence. 

The sequences of the amino acids in the chains from which proteins are constructed are encoded in the nucleotide sequences of DNA (deoxyribonucleic acid). The coding sequence for a protein in the DNA is found in the structural gene for that protein. The RNA enzymes are also encoded by DNA genes. A fourth major theme of the book deals with the nature of the genetic code used in DNA and with the processes by which cells read and interpret the code. It also includes study of the methods by which thousands of genes have been mapped to specific positions in chromosomes, isolated, cloned, and sequenced. 

As much of the terminology used in molecular biology may be unfamiliar to some readers, it is appropriate to define some of the vocabulary and this is given in an appendix to this chapter. There are two types of nucleic acids, the ribonucleic acids (RNA) and the deoxyribonucleic acids (DNA). Genetic information is carried in the linear sequence of nucleotides in DNA. Each molecule of DNA contains two complementary strands of deoxyribonucleotides which contain the purine bases, adenine and guanine and the pyrimidines, cytosine and thymine. RNA is single-stranded, being composed of a linear sequence of ribonucleotides the bases are the same as in DNA with the exception that thymine is replaced by the closely related base uracil. DNA replication occurs by the polymerisation of a new complementary strand on to each of the old strands. 

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. 

In the form of deoxyribonucleic acid (DNA), the macromolecular nucleic acids are of prime importance in biology because they carry the building plan for each living individual. They are identically reduplicated and inherited from one generation to the next, be it bacterium, plant, animal, or man. The information about every feature of and about every molecule contained in a living being is encoded in the nucleotide sequence of its DNA, which is read out and translated into the amino acid sequences of its proteins. In the many different steps involved in this protein biosynthesis, information transfer takes place which would be impossible without the weak hydrogen bonds. Because they can easily and rapidly be formed and broken, they are ideally suited for these dynamic processes which are so important for life. 

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