Nitrogen-fixing Actinorhizal Symbioses

Genomes and Genomics of Nitrogen-fixing Organisms This is Volume 3 of a seven-volume series on all aspects of Nitrogen Fixation. The series aims to be the definitive authority in the field and to act as a benchmark for some years to come. All authors are recognized practicing scientists in the area of their contribution, which ensures the high quality, relevance, and readability of the chapters.

Expanding Horizons in Bioethics Like its predecessor, New Dimensions in Bioethics, this volume developed out of a series of lectures at Yale University’s Institution for Social and Policy Studies. Each of the more successful participants was invited to contribute a manuscript for publication. More recently, developments in the analysis of the human genome, the enticing medical possibilities offered by the therapeutic use of stem cells, the complexities surrounding the cloning of animals and possibly humans and the development of transgenic agricultural crops have given new impetus to the expansion of traditional bioethical horizons.

Of course, Klebsiella pneumoniae and Azotobacter vinelandii, which have served (and still serve) as the main model organisms for the genetic analysis of diazotrophy, plus some of the other bacteria described in this volume, did indeed select themselves.Once the editorial team was established, the first job was to decide which of the many free-living diazotrophs that have been subjected to genetic analysis should be included in this volume. Genetics and Regulation of Nitrogen Fixation in Free-Living Bacteria Volume II provides a comprehensive and detailed source of information concerning the genetics and regulation of biological nitrogen fixation in free-living prokaryotes. This preface attempts to provide the reader with some insight into how this volume originated, how it was planned, and then how it developed over the several years of its production.

The chapter covers the landmarks and scientific concepts that arose from more than one century of research in this area. Associative and Endophytic Nitrogen-fixing Bacteria and Cyanobacterial Associations. This volume does not deal with the Frankia-actinorhizal plant associations, which is the topic of Volume 6.

This book, with chapters authored by internationally renowned experts, provides a comprehensive and detailed account of the fascinating history of the process - including the surprising discoveries of molybdenum-independent nitrogenases and superoxide-dependent nitrogenase; a review of Man's attempts to emulate the biological process - most successfully with the commercially dominant Haber-Bosch process; and the current state of the understanding art with respect to the enzymes - called nitrogenases - responsible for biological nitrogen fixation. Biological nitrogen fixation provides more than 50% of the total annual input of the essential element nitrogen to world agriculture. The next set of chapters focuses on the classical enzyme, the molybdenum nitrogenase, and details its biosynthesis, structure, composition, and mechanism of action as well as detailing both how variants of its two component proteins are constructed by recombinant DNA technology and how computational techniques are being applied.

Nitrogen-fixing Leguminous Symbioses.

Once the editorial team was established, the first job was to decide which of the many free-living diazotrophs that have been subjected to genetic analysis should be included in this volume. Genetics and Regulation of Nitrogen Fixation in Free-Living Bacteria Volume II provides a comprehensive and detailed source of information concerning the genetics and regulation of biological nitrogen fixation in free-living prokaryotes.

As in previous volumes of this series, the first chapter presents an historical perspective and describes the development of actinorhizal research with its focus on the period after the first reproducible isolation of the responsible microorganism by John Torrey’s group in 1978..

Genetics and Regulation of Nitrogen Fixation in Free-Living Bacteria Volume II provides a comprehensive and detailed source of information concerning the genetics and regulation of biological nitrogen fixation in free-living prokaryotes. This preface attempts to provide the reader with some insight into how this volume originated, how it was planned, and then how it developed over the several years of its production. Of course, Klebsiella pneumoniae and Azotobacter vinelandii, which have served (and still serve) as the main model organisms for the genetic analysis of diazotrophy, plus some of the other bacteria described in this volume, did indeed select themselves.

However, after Frankia strains were isolated from nodules and pure cultures became available, many of these early results had to be discarded. These efforts led to the emendation of the family Frankiaceae with the type genus Frankia and also to the definition of host-specificity groups based on inoculation experiments using crushed nodules.