Deoxyribonucleic acid poly

Ti values may occur with such native biopolymers as ribonuclease A, deoxyribonucleic acid, and collagen, whose molecular motions are restricted, but, as yet, high values have not been observed for polysaccharides in solution, or for gels, in which these motional-restriction effects may be equivalent, or less marked. However, an extensive relaxation-study by Levy and coworkers68 on poly(n-alkyl methacrylates) may serve as a model for future experiments on polysaccharides, as this type of molecule has a main chain and side chains, albeit more mobile than those in polysaccharides. 

Disulfide bridge. A covalent linkage formed by oxidation between two SH groups either in the same polypeptide chain or in different polypeptide chains. DNA. Deoxyribonucleic acid. A poly-deoxyribonucleotide in which the sugar is deoxyribose the main repository of genetic information in all cells and most viruses. 

Dimicoli, J. L. and Helene, C., Interactions of aromatic residues of proteins with nucleic acids. I. Proton magnetic resonance studies of the binding of tryptophan-containing peptides to poly(adenylic acid) and deoxyribonucleic acid, Biochemistry, 13(4], 714, 1974. 

AcK acetate kinase AcP acetyl phosphate AdK adenylate kinase AP A p ,pn-di(adenosine 5 -) n-phosphate ARS aminoacyl tRNA synthetase ATP, ADP, AMP adenosine 5 -tri-, di-, monophosphate ATP-u-S (Sp)-adenosine 5 -0-(l-thiotriphos-phate), ATP-y-S adenosine 5 -0-(3-thiotriphosphate) CK carbamyl kinase CP carbamyl phosphate CrK creatine kinase CTP, CDP, CMP cytidine 5 -tri-, di-, monophosphate dATP, dAMP deoxyadenosine 5 -tri-, monophosphate DNA deoxyribonucleic acid AG change in free energy GK glycerol kinase GTP, GDP, GMP guanosine 5 -tri-, di-, monophosphate HK hexokinase IUB International Union of Biochemistry MCP methoxycarbonyl phosphate NTP, NDP, NMP nucleoside 5 -tri-, di-, monophosphate PC phosphocreatine PEP phosphoenol pyruvate P orthophosphate PK pyruvate kinase P polyphosphate PnK poly-... 

Complimentary deoxyribonucleic acid (cDNA) synthesis was conducted in 50-pL reaction. Poly-A RNA (60 ng) was mixed with 1 pg of oligo dT, 3 p,g of random hexamer, and DEPC-treated water to a final volume of 34 pL. 

The two types of natural polynucleotides (nucleic acids) are classified according to the sugars they contain. Ribonucleic acid (RNA) contains exclusively P-o-ribose, while the sugar in deoxyribonucleic acid (DNA) is P-2-deoxy-D-ribose. Different nucleic acids can have from around 80 nucleotides (nt), as in transfer RNA (tRNA), to over 10 nucleotide-pairs in a single eukaryotic chromosome. The unit for size of nucleic acid is the base (for single-stranded species) or the base-pair (bp, for double-stranded species), with the unit Kb (thousand base-pairs) and Mb (million base-pairs). Examples of synthetic homopolynucleotides are poly(uridylate) or poly(deoxyadenylate), in poly(U) or poly(dA)... 

In principle, polymers consisting of a single kind of chiral monomeric unit can produce left- and right-handed helices. But the two kinds of helix are diastereomeric to each other that is, they are not energetically equal. For this reason, either left or right-handedness is a preferred form for such polymers. For example, polymers of chiral (S)-a-olefins and most poly(D-saccharides) form exclusively left-handed helices. On the other hand, deoxyribonucleic acids and almost all poly(L-a-amino acids) occur as right-handed helices. Polymers of the corresponding monomer antipodes form helices of opposite turn. 

Macroconformations consisting of two or three helices intertwined with each other are also sometimes called super helices or super secondary structures. An example is deoxyribonucleic acid, which forms a double helix from two complementary chains, each in the form of a helix (see Section 29). With synthetic polymers, both it-poly(methyl methacrylate) and poly(/ -hydroxybenzoic acid) appear to form double helices. Triple helices are, for example, formed by the protein, collagen (see Section 30). 

A key feature of the above equations is that the reactions in Equation (4.1a) are reversible, but those represented in Equation (4.1b) are irreversible. This represents the very significant means whereby synthesis of the gene, the poly(deoxyribonucleic acid) encoding for protein, is an irreversible process. Another important expense of energy is that only intermittent parts, called exons, of the DNA sequence (the gene) actually encode for protein. For the DNA that encodes elastin, less than 20% is exon, the remainder, called introns, does not encode for the protein. In addition, there is much junk DNA carried along during replication that appears to serve no useful purpose. 

Cohen JJ, Catino DM, Petzold SJ, Berger NA (1982) Activation of poly (adenosine diphosphate ribose) polymerase by SV40 minichromosomes effects of deoxyribonucleic acid damage and histone HI. Biochemistry 21 4931-4940... 

Sims JL, Sikorski GW, Datino DM, Berger S, Berger NA (1982) Poly (adenosine diphospho-ribose) polymerase inhibitors stimulate unscheduled deoxyribonucleic acid synthesis in normal human lymphocytes. Biochemistry 21 1813-1821... 

James MR, Lehmann AR (1982) Role of poly(adenosine diphosphate ribose) in deoxyribonucleic acid repair in human fibroblasts. Biochemistry 21 4007-4013... 

Figure 1.4. Chiral supramolecular structures (a) a-helix of polypeptides, (b) poly-prolin-helix of collagene, and (c) deoxyribonucleic acid (DNA) Z = D-Deoxyribose, P = phosphoric acid, A — adenine, G = guanine, C = cytosine, T = thymine (from [8]).

Solutions of rod-like entities in a normally isotropic solvent often form liquid-crystal phases for sufficiently high solute concentration. These anisotropic solution mesophases are called lyotropic liquid crystals". Although the rod-like entities are usually quite large compared with typical thermotropic liquid-crystal mesogens, their axial ratios are seldom greater than 15. Deoxyribonucleic acid (DNA), certain viruses (e.g., tobacco mosaic virus (TMV)), and many synthetic poly-... 

---