Nucleic acids enzymology

Many chemical reactions occur within biological cells. A special class of protein molecules called enzymes speed up or control these reactions. Chemical reactions need a certain amount of activation energy to take place, and enzymes can increase reaction speed by allowing a different reaction path with a lower activation energy, making it easier for the reaction to occur. Enzymes are essential for the function of cells. They are very specific to the reactions they catalyze and the chemical substrates that are involved in the reactions. Enzymes are said to fit their substrate like a key fits its lock. 

The control of the expression of proteins by DNA genes reUes on special proteins that bind to specific DNA sequences. The way in which these proteins recognize their binding sites in the genome is an important step in understanding how these processes occur at the molecular level. 

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Provide an overview of the processes of recombinant DNA technology. Appreciate the central roles played by nucleic acid enzymology and nucleic acid hybridization in enabling the methodology. 

This chapter lists some representative examples of biochemicals and their origins, a brief indication of key techniques used in their purification, and literature references where further details may be found. Simpler low molecular weight compounds, particularly those that may have been prepared by chemical syntheses, e.g. acetic acid, glycine, will be found in Chapter 4. Only a small number of enzymes and proteins are included because of space limitations. The purification of some of the ones that have been included has been described only briefly. The reader is referred to comprehensive texts such as the Methods Enzymol (Academic Press) series which currently runs to more than 344 volumes and The Enzymes (3rd Edn, Academic Press) which runs to 22 volumes for methods of preparation and purification of proteins and enzymes. Leading referenees on proteins will be found in Advances in Protein Chemistry (59 volumes. Academic Press) and on enzymes will be found in Advances in Enzymology (72 volumes, then became Advances in Enzymology and Related Area of Molecular Biology, J Wiley Sons). The Annual Review of Biochemistry (Annual Review Inc. Patio Alto California) also is an excellent source of key references to the up-to-date information on known and new natural compounds, from small molecules, e.g. enzyme cofactors to proteins and nucleic acids. 

Staden, R. (1999). Finding protein coding regions in genomic sequences. In Doolittle, R. (ed.), Molecular Evolution Computer Analysis of Protein and Nucleic Acid Sequences, Methods in Enzymology. vol. 183. Academic Press, San Diego. 

Selected entries from Methods in Enzymology [vol, page(s)] Anisotropy effects, 261, 427-430 determination by dynamic laser light scattering (quasi-elastic light scattering), 261, 432-433 determination for nucleic acids by NMR [accuracy, 261, 432-433 algorithms, 261, 11-13, 425, 430 carbon-13 relaxation, 261, 11-12, 422-426, 431, 434-435 cross-relaxation rates, 261,419-422, 435 error sources, 261, 430-432 phosphorus-31 relaxation, 261, 426-427, 431 proton relaxation, 261,51,418-422 relaxation matrix calculations, 261,12] deuterium solvent viscosity effects, 261,433 effect... 

Selected entries from Methods in Enzymology [vol, page(s)] . Applications, 246, 335 [immunoassay, 246, 343-344 nucleic acids, 246, 344-345 photoreceptors, 246, 341-343 protein conformation, 246, 339-340 protein-membrane interactions, 246, 340-341 two-dimensional imaging, 246, 345] energy level diagram, 246, 336 excited state decay kinetics, 246, 337-338 in-... 

C.W.Carter (ed.). Protein and Nucleic Acids Crystallisation Methods - A Companion to Methods in Enzymology, Academic Press, NY, 1 12 1990. 

To explain the enzymology of DNA replication, we first introduce the enzymes that degrade DNA rather than synthesize it. These enzymes are known as nucleases, or DNases if they are specific for DNA rather than RNA. Every cell contains several different nucleases, belonging to two broad classes exonucleases and endonucleases. Exonucleases degrade nucleic acids from one... 

This chapter deals with microbial RNases (1) of interest because of their enzymology or their use in nucleic acid research, with special reference to fungal RNases. 

Other microbial RNases of special interest from points of view of enzymology or of nucleic acid chemistry are briefly mentioned below. 

From the complementary duplex structure of DNA described in chapter 25, it is a short intuitive hop to a model for replication that satisfies the requirement for one round of DNA duplication for every cell division. In chapter 26, DNA Replication, Repair, and Recombination, key experiments demonstrating the semiconservative mode of replication in vivo are presented. This is followed by a detailed examination of the enzymology of replication, first for how it occurs in bacteria and then for how it occurs in animal cells. Also included in this chapter are select aspects of the metabolism of DNA repair and recombination. The novel process of DNA synthesis using RNA-directed DNA polymerases is also considered. First discovered as part of the mechanisms for the replication of nucleic acids in certain RNA viruses, this mode of DNA synthesis is now recognized as occurring in the cell for certain movable genetic segments and as the means whereby the ends of linear chromosomes in eukaryotes are synthesized. 

Doolittle, R.F. 1990. Molecular evolution Computer analysis of protein and nucleic acid sequences. In Methods in Enzymology, Vol. 183, R. F. Doolittle, Ed. Academic Press, Inc. San Diego, Chapter 6. 

Ized such as carbohydrates, nucleic acids, lipids, and proteins may prove available by enzymic synthetic methods. Enzymology will be useful in modifications of poly- and oligosaccharides and proteins. Enzymes will also see growth in applications in medical diagnostics and treat-... 

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