Dna Topology And Its Biological Effects

"A key aspect of DNA is its ability to form a variety of structures, this book explains the origins and importance of such structures"--Provided by publisher.

DNA Topoisomerase Protocols, I: DNA Topology and Enzymes brings together an unprecedented collection of cutting-edge experimental protocols for investigating DNA structure, topology, and DNA topoisomerase function. Described by expert experimentalists who have perfected the techniques, these unfailingly reproducible methods utilize new approaches to study changes in DNA topology (linking number, knotting, catenation, and relaxation) and DNA structure (bending), as well as to assess chromosome structure through FLP-mediated recombination and to analyze bacterial nucleoid structure. State-of-the-art protocols also detail the expression and purification of bacterial, viral, and eukaryotic DNA topoisomerases from a variety of sources, including baculovirus, and bacterial, yeast and mammalian expression systems. A companion volume, DNA Topoisomerase Protocols, v. 2: Enzymology and Drugs, provides detailed protocols to study the catalytic activities of DNA topoisomerases, as well as their specific interactions with topoisomerase-targeted antitumor and antibacterial drugs. DNA Topoisomerase Protocols, I: DNA Topology and Enzymes will be of immense value to the many basic scientists and clinicians who want better to understand and to exploit proficiently the wealth of recent discoveries about chromatin structure and its relation to gene expression, about DNA topoisomerases as the targets of antitumor and antibacterial agents, and about DNA repair.

Beginning with the Escherichia coli ? protein, or bacterial DNA topoisomerase I, an ever-increasing number of enzymes have been identified that catalyze changes in the linkage of DNA strands. DNA topoisomerases are ubiquitous in nature and have been shown to play critical roles in most p- cesses involving DNA, including DNA replication, transcription, and rec- bination. These enzymes further constitute the cellular targets of a number of clinically important antibacterial and anticancer agents. Thus, further studies of DNA topology and DNA topoisomerases are critical to advance our und- standing of the basic biological processes required for cell cycle progression, cell division, genomic stability, and development. In addition, these studies will continue to provide critical insights into the cytotoxic action of drugs that target DNA topoisomerases. Such mechanistic studies have already played an important role in the development and clinical application of antimicrobial and chemotherapeutic agents. The two volumes of DNA Topoisomerase Protocols are designed to help new and established researchers investigate all aspects of DNA topology and the function of these enzymes. The chapters are written by prominent investigators in the field and provide detailed background information and st- by-step experimental protocols. The topics covered in Part I: DNA Topology and Enzymes, range from detailed methods to analyze various aspects of DNA structure, from linking number, knotting/unknotting, site-specific recombi- tion, and decatenation to the overexpression and purification of bacterial and eukaryotic DNA topoisomerases from a variety of cell systems and tissues.

Molecular Biology of DNA Topoisomerases and Its Application to Chemotherapy is based on conference proceedings from the International Symposium on DNA Topoisomerases in Chemotherapy, held in Nagoya, Japan, in November 1991. The book opens with a discussion of the structural and functional properties of various types of DNA topoisomerases identified in prokaryotes and eukaryotes, in addition to their roles as cellular targets of anticancer and antimicrobial agents. Other topics addressed include the genetics and biology of DNA topoisomerases, inhibitors of microbial DNA topoisomerases and drug resistance, inhibitors of mammalian DNA topoisomerases and drug resistance, and preclinical and clinical studies of DNA topoisomerase inhibitors. Molecular Biology of DNA Topoisomerases and Its Application to Chemotherapy will broaden the understanding of biology and genetics of DNA topoisomerases and contribute to the development of antimicrobial and anticancer agents-inhibitors of topoisomerases. It will be invaluable for oncologists, molecular biologists, cellular biologists, geneticists, biochemists, and pharmaceutical researchers.

Topology and Physics of Circular DNA presents comprehensive coverage of the physical properties of circular DNA. The author examines how topological constraints arising from cyclization of DNA lead to distinctive properties that make closed molecules radically different from linear DNA. The phenomenon of supercoiling, its geometric and topological analysis, and the formation of noncanonical structures in circular DNA under the influence of supercoiling are emphasized. The combination of consistent theoretical analysis and detailed treatment of major experimental approaches make Topology and Physics of Circular DNA an important reference volume for biophysicists, biochemists, molecular biologists, and researchers and students who want to expand their understanding of circular DNA.