Since penicillin and salvarsan were discovered, a number of new drugs to combat infectious diseases have been developed, but at the same time, the number of multi-resistant microorganism strains is increasing. Thus, the design of new and effective antibacterial, antiviral and antifungal agents will be a major challenge in the next years. This book reviews the current state-of-the-art in antimicrobial research and discusses new strategies for the design and discovery of novel therapies. Topics covered include the use of genetic engineering, genome mining, manipulation of gene clusters, X-ray and neutron scattering as well as the antimicrobial effects of essential oils, antimicrobial agents of plant origin, beta-lactam antibiotics, antimicrobial peptides, and cell-wall-affecting antifungal antibiotics.

The world is full of plants and animals that have their own defenses, producing various substances in their daily fight against bacteria, fungi, or other agents. These products are alternatives to conventional antimicrobials that have a poor reputation with consumers. Many of these compounds are well known; however, the multiple types of structures together with the variable responses depending of the type of biocontrol needed in a wide range of applications, such as clinical, agricultural, general hygiene, and food, necessitates the continuous search for specific applications and the continuous study of how to use these substances. The present book provides a summary of reviews and original research works that explore the multiple alternatives for the use of these compounds.

The rapid advances made in the study of the synthesis, structure and function of biological macromolecules in the last fifteen years have enabled scientists concerned with antimicrobial agents to achieve a considerable measure of understanding of how these substances inhibit cell growth and division. The use of antimicrobial agents as highly specific inhibitors has in turn substantially assisted the investigation of complex biochemical processes. The literature in this field is so extensive however, that we considered an attempt should be made to draw together in an introductory book the more significant studies of recent years. This book, which is in fact based on lecture courses given by us to undergraduates at Liverpool and Manchester Universities, is therefore intended as an introduction to the biochemistry of antimicrobial action for advanced students in many disciplines. We hope that it may also be useful to established scientists who are new to this area of research. The book is concerned with a discussion of medically important antimicrobial compounds and also a number of agents that, although having no medical uses, have proved invaluable as research tools in biochemistry. Our aim has been to present the available information in a simple and readable way, emphasizing the established facts rather than more controversial material. Whenever possible, however, we have indicated the gaps in the present knowledge of the subject where further information is required.

Documenting the latest research in the field of different pathogenic organisms, this book presents the current scenario about promising antimicrobials in the following areas: Part I. Plants as source of antibacterials, Part II. Naturally occurring antifungal natural products, Part III. Antiparasitic natural products, Part IV. Antiviral natural products. Renowned scientists from the globe have been selected as authors to contribute chapters. Use of plants for various ailments is as old as human civilization and continuous efforts are being made to improve medicinal plants or to product their bioactive secondary metabolites in high amounts through various technologies. About 200,000 natural products of plant origin are known and many more are being identified from higher plants and micro-organisms. Some plants based drugs are used since centuries and there is no alternative medicine for many such drugs as cardiac glycosides. Drug discovery from medicinal plants or marine micro-organisms continues to provide an important source of new drug leads. Research on new antibacterials represents a real and timely challenge of this century, particularly for the treatment of infections caused by clinical isolates that show multidrug resistance. The main microorganisms involved in the resistance process have been identified and given the acronym ESKAPE for Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa and Enterobacteriaceae. Multidrug resistant Mycobacterium tuberculosis including highly drug-resistant strains (XDR-TB) has also emerged as one of the most important clinical challenges of this century. Plants of diverse taxa and marine micro-organisms are rich source of these antimicrobials. An attempt has been made to compile the recent information about natural sources of antibacterials and their sustainable utilization. Increased panic of these pathogens warrants a growing demand for research to undertake the threat of multidrug resistance. The search for new antifungal, antiparasitic and antiviral natural products is far from devoid of interest. According to the WHO report in 2013, malaria still represents some 207 million cases worldwide and more than 3 billion of people are still exposed to this risk. Similarly, about 350 million people are considered at risk of contracting leishmaniasis. The fight against some viruses also requires that the research on natural products continue. For example, even if an antiretroviral with direct action was recently approved in Europe in 2013, its high cost does not allow to offer it to an exposed population in countries where the cost of drugs remains a problem for a large part of the population. These books are useful to researchers and students in microbiology, biotechnology, pharmacology, chemistry and biology as well as medical professionals.

Humans coexist with millions of harmless microorganisms, but emerging diseases, resistance to antibiotics, and the threat of bioterrorism are forcing scientists to look for new ways to confront the microbes that do pose a danger. This report identifies innovative approaches to the development of antimicrobial drugs and vaccines based on a greater understanding of how the human immune system interacts with both good and bad microbes. The report concludes that the development of a single superdrug to fight all infectious agents is unrealistic.

The clinical microbiology laboratory is often a sentinel for the detection of drug resistant strains of microorganisms. Standardized protocols require continual scrutiny to detect emerging phenotypic resistance patterns. The timely notification of clinicians with susceptibility results can initiate the alteration of antimicrobial chemotherapy and