Mechanism Of Actin Nucleation By The Listeria Monocytogenes Acta Protein

Since the discovery of actin by Straub in the 1950’s and the pioneering work of Oosawa on actin self-assembly in helical laments in the 1960’s, many books and conference proceedings have been published. As one of the most essential p- teins in life, essential for movement in organisms rangingfrom bacteria to higher eukaryotes, it is no surprise that actin has fascinated generations of scientists from many different elds. Actin can be considered as a “living treasure” of biology; the kinetics and thermodynamics of self-assembly, the dissipative nature of actin po- merization, the molecular interactions of monomeric and polymerized actin with regulators, the mechanical properties of actin gels, and more recently the force p- ducing motile and morphogenetic processes organized by the actin nanomachine in response to signaling, are all milestones in actin research. Discoveries that directly derive from and provide deeper insight into the fundamental properties of actin are constantly being made, making actin an ever appealing research molecule. At the same time, the explosion in new technologies and techniques in biological sciences has served to attract researchers from an expanding number of disciplines, to study actin. This book presents the latest developments of these new multiscale approaches of force and movement powered by self-assembly processes, with the hope to opening our perspectives on the many areas of actin-based motility research.

Actin is one of the most abundant proteins and ubiquitously expressed in all eukaryotes. In recent years, the analysis of structure and function of such complexes has shed new light on actin's role in cellular and tissue morphogenesis, locomotion and various forms of intracellular motility, but also on its role in nuclear processes like chromatin architecture and transcription. Progress in understanding these different physiological phenomena, but also in unravelling the basis of actin-based pathophysiological processes has been made by combining video microscopy, molecular biology, genetics and biochemistry. Thus, the current research on actin, as ongoing in many international laboratories, is a "hot spot" in basic and translational research in life sciences. In this book on "The Actin Cytoskeleton", twelve internationally renowned authors present specific chapters that cover their recent work concerned with the various roles of actin mentioned above. This comprehensive volume is therefore an attractive handbook for teachers and students in many fields of medicine and pharmacology.

Shigellosis is present all over the world. Anyone traveling in developing countries knows that the control of this invasive disease of the intestine is a priority task for physicians and public health authorities. Victims are essentially young children, and complications such as the hemolytic uremic syndrome make shigellosis a systemic disease rather than simply an infection of the colonic mucosa. However, "Westerners" should not consider shigeJlosis as an unlikely threat of the tropics. The disease arises in industrialized countries as soon as breaches in sanitation appear. A few months ago, at least 500 people developed shigellosis in northern France in an outbreak of Shigella sonnei infection due to accidental contamination of an urban water delivery system. The pathogenesis of shigellosis is an extraordinary topic of research because study of the invasion of the colonic mucosa addresses fundamental questions on. the molecular and cellular mechanisms by which a bacterial pathogen can pene trate non phagocytic cells, survive, multiply, spread in the intra cellular compartment, and eventually kill host cells. Further development of the infection within subepithelial tissues as well as the mechanisms that contribute to the eradication of this process have barely been studied.

This volume describes the mechanisms which bacteria have created to secure their survival, proliferation and dissemination by subverting the actin cytoskeleton of host cells. Bacteria have developed a veritable arsenal of toxins, effector proteins and virulence factors that allow them to modify the properties of the intracellular actin cytoskeleton for their own purposes. Bacterial factors either modify actin directly as the main component of this part of the cytoskeleton or functionally subvert regulatory or signalling proteins terminating at the actin cytoskeleton. In short, this volume provides an overview of the various tricks bacteria have evolved to “act on actin” in order to hijack this essential host cell component for their own needs. As such, it will be of interest to scientists from many fields, as well as clinicians whose work involves infectious diseases.

Microbiology has undergone radical changes over the past few decades, ushering in an exciting new era in science. In The New Microbiology, Pascale Cossart tells a splendid story about the revolution in microbiology, especially in bacteriology. This story has wide-ranging implications for human health and medicine, agriculture, environmental science, and our understanding of evolution. The revolution results from the powerful tools of molecular and cellular biology, genomics, and bioinformatics, which have yielded amazing discoveries, from entire genome sequences to video of bacteria invading host cells. This book is for both scientists and especially nonscientists who would like to learn more about the extraordinary world of bacteria. Dr. Cossart's overview of the field of microbiology research, from infectious disease history to the ongoing scientific revolution resulting from CRISPR technologies, is presented in four parts. New concepts in microbiology introduces the world of bacteria and some recent discoveries about how they live, such as the role of regulatory RNAs including riboswitches, the CRISPR defense system, and resistance to antibiotics. Sociomicrobiology: the social lives of bacteria helps us see the new paradigm by which scientists view bacteria as highly social creatures that communicate in many ways, for example in the assemblies that reside in our intestine or in the environment. The biology of infections reviews some of history's worst epidemics and describes current and emerging infectious diseases, the organisms that cause them, and how they produce an infection. Bacteria as tools introduces us to molecules derived from microbes that scientists have harnessed in the service of research and medicine, including the CRISPR/Cas9 genome-editing technology. The New Microbiology takes us on a journey through a remarkable revolution in science that is occurring here and now.