Bøger i Molecular Biology, Biochemistry and Biophysics Molekularbiologie, Biochemie und Biophysik serien

Certain enzymes with a variety of regulatory and catalytic functions, for example, contain several sites which interact in a highly specific manner such that the affinity of a given site for the substrate is markedly influenced by the state of binding at the other sites.

These reac tions, in accord with CZAPEK (1921) and PAECH (1950), are summed up under the term "secondary metabolism", and their products are called "secondary metabolites.

The application of circular dichroism (CD) to various problems involving con formation of proteins and other biopolymers is emphasized in this revised and enlarged second edition. SPRINGER, M.D., for their interest in this edition, as well as to the many reviewers for their constructive criticism of the first edition of this book.

Among terrestrial plants the vascular plants are the largest and the most con spicuous. Thus lignin is found in vascular plants such as lycopods, ferns, gymnosperms and angiosperms, whereas it is absent from simple plants such as fungi, and from all other organisms.

This book is based on practical experience and is therefore written as a prac tical manual. There are many other sensitive and excellent micro methods which are not included in this book, because the authors feel that in a "cook book" only methods for which they have personal experience and profi ciency should be described.

This book deals primarily with the principal extracellular macromole cules of animal connective tissues. On the other hand, I have not hesitated to search for broad biological principles outside the prevailing conceptual boundaries of animal connective tissues and the lower molecular dimensional levels.

In 1965 I was asked by Dr. Konrad Springer whether I would consider writing a monograph on "Lampbrush chromosomes and their physiological meaning", and although I accepted in principle I refused to write there and then, or to meet a deadline.

A dinner party at his apartment is among the warmest of my memories, and nothing could please me more than to have the opportunity to introduce him in per son to my colleagues in Western Europe, the Americas, Japan, and Australia.

In 1966, a paper entitled "On the formation of a novel adenylylic compound by enzymatic extracts of liver nuclei" from Paul Mandel's laboratory in Strasbourg, France, planted the seed for a rapidly growing new field of biological research focusing on ADP-ribosylation reactions.

The main emphasis is put on the molecular aspect by relating the bioelectrical phenomena, such as the membrane diffusion potentials, pump potentials, or redox potentials, to the properties of the membrane concerned, and, as far as pOSSible, to specific steps of transport and metabolism of ions and nonelectrolytes.

With contributions by numerous experts

With contributions by numerous experts

Special emphasis has been given to the analysis of the Hill coefficient and its meaning both in thermodynamic terms and in terms of the two allosteric models: the concerted model of Monod, Wyman and Changeux and the sequential model of Koshland, Nemethy and Filmer.

The authors belong to a group formed under the aegis of the Com mission of the European Communities some eight years ago with the object of facilitating the exchange of ideas and inforrration between European scientists working in this field.

The principles described in the latter discus sions are broadly applicable, for example to the promising tech niques of X-ray spectroscopy (utilizing synchrotron radiation) and lanthanide-perturbed, very high-resolution nuclear magnetic resonance spectroscopy.

A systematic study traced the cause of this absorption, showing that the covered frequency range and the intensity of the absorption were related in a predictable manner to the rate at which ions can interact and form structures differing in volume from the non interacting species.

Enzyme kinetics has undergone very rapid growth and development during the past fifteen years and has been well received by the biochemical community.

In the few years since the first edition of this book made its appearance, under takings in the area of protein sequence determination have increased at an almost logarithmic pace.

The treatment is of a survey fashion, in part to pro vide a general over-view of N2 fixation and in part to provide context for the biochemistry and biophysics that follow in the second section.

Although the biochemistry of nucleic acid synthesis is known in general, the precise molecular mechanisms by which deoxyribonucleic acid is replicated or transcribed has still to be clarified.

The tissues and organs covered in six chapters constitute a selected group, representative of areas in which the author has worked and which are thus directly familiar to him, plus several other areas where illustrative and important discoveries have been made.

The alkaloids were of great importance to mankind for centuries, long before they were recognized . Since that time they have remained of great interest to chemists, and now in any month there appear dozens of publications dealing with the isolation of new alkaloids or the determination of the structures of previously known ones.

In the conviction that research into the nature of protamine would shed light on that of other typical proteins, a group of researchers in Germany followed MIESCHER and laid the foundations of protein chemistry.