Biodegradative Bacteria highlights the novel nature of bacterial cell functions in the field of biodegradation by putting them into three parts: (1) Genetic and genomic systems, (2) Degradative enzyme systems, and (3) Bacterial behavior in natural environmental systems. The first part of the book includes cell functions as degradative machinery, genome systems for effective degradation, and the evolution of degradative systems by mobile genetic elements. The second part deals with the structure, function, evolution, diversity, and application of degradative and related enzymes. The third part presents cell or genomic behaviors of biodegradative bacteria in natural ecosystems. Bacterial metabolic capacity, which plays an important role in the global material cycle, contributes significantly to the buffering capacity for the huge and unintended release of various chemicals. Recently, however, the prosperity and globalization of material civilization has led not only to severe local contamination by hazardous chemicals, but also to continuous increment of contaminant concentrations worldwide. To solve such urgent global issues, bacterial functions that are involved in biodegradation of hazardous chemicals have been analyzed. The term "biodegradative bacteria" refers to those bacteria that have the ability to degrade such xenobiotic (man-made) and/or hazardous chemicals. Analyses of biodegradative bacteria include diverse areas of study, such as genetics, enzymology, genomics, cell physiology, ecology, and evolutionary biology. In other words, the targets investigated in research on biodegradative bacteria include single molecules, single cell systems, bacterial consortia (interaction with surrounding microorganisms), and interaction with surrounding biotic and abiotic materials. Such complexity makes the research on biodegradative bacteria difficult but quite interesting.

The aim of this book is to provide readers with a wide overview of the main healthcare-associated infections caused by bacteria and fungi able to grow as biofilm. The recently acquired knowledge on the pivotal role played by biofilm-growing microorganisms in healthcare-related infections has given a new dynamic to detection, prevention and treatment of these infections in patients admitted to both acute care hospitals and long-term care facilities. Clinicians, hygienists and microbiologists will be updated by leading scientists on the state-of-art of biofilm-based infections and on the most innovative strategies for prevention and treatment of these infections, often caused by emerging multidrug-resistant biofilm-growing microorganisms.

Described as the earliest, simplest life forms, with unlimited metabolic versatility, bacteria are ideally suited to answer some very fundamental questions on life and its processes. They have been employed in almost all fields of biological studies, including Genetics. The whole edifice of science of Genetics centers around three processes: the generation, expression, and transmission of biological variation, and bacteria offer immediate advantages in studying all the three aspects of heredity. Being haploid and structurally simple, it becomes easy to isolate mutations of various kinds and relate them to a function. The availability of such mutants and their detailed genetic and biochemical analyses lead to a gamut of information on gene expression and its regulation. While studying the transmission of biological variation, it is clear that unlike their eukaryotic counterpart, a more genetic approach needs to be employed. Transmission of genetic information in most eukaryotic organisms rests on sexual reproduction that allows the generation of genetically variable offspring through the process of gene recombination. Even though bacteria show an apparent preference for asexual reproduction, they too have evolved mechanisms to trade their genetic material. In fact, bacteria not only could acquire many genes from close relatives, but also from entirely distant members through the process of horizontal gene transfer. Their success story of long evolutionary existence will stand testimony to these mechanisms. While teaching a course on Microbial Genetics to the post-graduate students at Delhi University, it was realized that a book devoted to bacterial genetics may be very handy to the students, researchers, and teachers alike. A strong foundation in genetics also helps in comprehending more modern concepts of molecular biology and recombinant DNA technology, always a favorite with the students and researchers. Planning the format of the book, emphasis has been laid on the generation and transmission of biological variability. The omission of expression part is indeed intentional because lots of information is available on this aspect in any modern biology book. The contents are spread over seven chapters and the text is supported with figures/tables wherever possible. The endeavor has been to induce the readers to appreciate the strength of bacterial genetics and realize the contribution of these tiny organisms to the growth of biological sciences as a whole and genetics in particular.

Combining the disciplines of biological, physical and chemical science, microbial forensics has a rapidly rising profile in a world increasingly troubled by the threat of 'biocrime' and 'bioterrorism'. This valuable resource is a major addition to a body of literature reckoned to lack sufficient breadth. It presents a variety of phenotypic and trace signature methodologies associated with cultured microorganisms that, despite being genetically identical, may be characterized by differing cultural environments. One of the central challenges faced by those working in this field is the sheer diversity of potentially harmful agents, which in themselves total more than 1000 viruses, bacteria, fungi and protozoan parasites. Their numerous additional variants render the process of 'fingerprinting' biological agents notoriously difficult, especially when the limitations of genetic analysis are factored in. Attribution of crime is relatively easy through human DNA, but lacking the genetic individuation of humans and animals, microbial forensics has to complement phylogenetic techniques with chemical and physical ones. In the best case, genetic analysis in the 'biocrime' sector can exclude sources, narrow the population of possible sources and support associations with potential sources. To complement these genetic techniques, chemical and physical methods can be used to compare 'signatures' imparted to microbial samples by environments in which they are grown and processed. Collating a range of microbiological fingerprinting techniques in one volume, and covering everything from statistical analysis to laboratory protocols, this publication furthers the aim of forensic investigators who need robust and legally admissible forensic evidence to present in a courtroom.

Interest in the field of microbial toxins is ever growing and spreading across a broad spectrum of scientific disciplines. In an effort to supplement the available reference texts on toxins, Microbial Toxins: Methods and Protocols includes protocols on mold fungus toxins, with some focus on aflatoxins. Intended to support a wide variety of researchers, Microbial Toxins: Methods and Protocols presents the reader with biological, chemical, physical, and medical approaches, as well as state-of-the-art research techniques. Divided into three convenient sections, this detailed volume covers bacterial protein toxins, endotoxins, and mold fungus toxins. Written in the highly successful Methods in Molecular Biology (TM) series format, chapters contain introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and notes on troubleshooting and avoiding known pitfalls. Authoritative and accessible, Microbial Toxins: Methods and Protocols seeks to serve both professionals and novices with its well-honed methodologies in an effort to further our knowledge of this essential field.

Most studies of bacterial or fungal infectious diseases focus separately on the pathogenic microbe, the host response, or the characterization of therapeutic compounds. Compartmentalization of pathogenesis-related research into an analysis of the "pathogen", the "host," or the "antimicrobial compound" has largely been dictated by the lack of model systems in which all of these approaches can be used simultaneously, as well as by the traditional view that microbiology, immunology, and chemical biology and pharmacology are separate disciplines. An increasing number of workers from different fields have turned to insects, fish, worms and other model hosts as facile, ethically expedient, relatively simple, and inexpensive hosts to model a variety of human infectious diseases and to study host responses and innate immunity. Because many of these hosts are genetically tractable, they can be used in conjunction with an appropriate pathogen to facilitate the discovery of novel features of the host innate immune response. This book provides a series of reports from the 1st International Conference on Model Hosts. This first of its kind meeting focused on invertebrate, vertebrate and amoeboid systems used for the study of host-pathogen interactions, virulence and immunity, as well as on the relevance of these pathogenesis systems and mammalian models. Importantly, a common, fundamental set of molecular mechanisms is employed by a significant number of microbial pathogens against a widely divergent array of metazoan hosts. Moreover, the evolutionarily conserved immune responses of these model hosts have contributed important insights to our understanding of the innate immune response of mammals. This book provides a series of reports from the 1st International Conference on Model Hosts. This first of its kind meeting focused on invertebrate, vertebrate and amoeboid systems used for the study of host-pathogen interactions, virulence and immunity, as well as on the relevance of these pathogenesis systems and mammalian models. Importantly, a common, fundamental set of molecular mechanisms is employed by a significant number of microbial pathogens against a widely divergent array of metazoan hosts. Moreover, the evolutionarily conserved immune responses of these model hosts have contributed important insights to our understanding of the innate immune response of mammals.

The application of new molecular methodologies in the study of bacterial behavior and cell architecture has enabled new revolutionary insights and discoveries in these areas. This new text presents recent developments in bacterial physiology that are highly relevant to a wide range of readership including those interested in basic and applied knowledge. Its chapters are written by international scientific authorities at the forefront of the subject. The value of this recent knowledge in bacterial physiology is not only restricted to fundamental biology. It also extends to biotechnology and drug-discovery disciplines.

Microbial relationships with all life forms can be as free living, symbiotic or pathogenic. Human beings harbor 10 times more microbial cells than their own. Bacteria are found on the skin surface, in the gut and other body parts. Bacteria causing diseases are the most worrisome. Most of the infectious diseases are caused by bacterial pathogens with an ability to form biofilm. Bacteria within the biofilm are up to 1000 times more resistant to antibiotics. This has taken a more serious turn with the evolution of multiple drug resistant bacteria. Health Departments are making efforts to reduce high mortality and morbidity in man caused by them. Bacterial Quorum sensing (QS), a cell density dependent phenomenon is responsible for a wide range of expressions such as pathogenesis, biofilm formation, competence, sporulation, nitrogen fixation, etc. Majority of these organisms that are important for medical, agriculture, aquaculture, water treatment and remediation, archaeological departments are: Aeromonas, Acinetobacter, Bacillus, Clostridia, Enterococcus, Pseudomonas, Vibrio and Yersinia spp. Biosensors and models have been developed to detect QS systems. Strategies for inhibiting QS system through natural and synthetic compounds have been presented here. The biotechnological applications of QS inhibitors (QSIs) in diverse areas have also been dealt with. Although QSIs do not affect growth and are less likely to impose selective pressure on bacteria, however, a few reports have raised doubts on the fate of QSIs. This book addresses a few questions. Will bacteria develop mechanisms to evade QSIs? Are we watching yet another defeat at the hands of bacteria? Or will we be acting intelligently and survive the onslaughts of this Never Ending battle?

Alicyclobacillus are not pathogenic bacteria, but they are troublesome, not only for consumers but also for beverage producers, because no effective control methods have yet been developed. It is against this background and in recognition of the importance and urgency of the problem that this book brings together new insights on the topic together with research published to date. The book uniquely focuses on one genus of bacteria. It aims to bring the information of Alicyclobacillus together and offer helpful understanding to control the bacteria for food industries.

Listeria monocytogenes is still a major threat to public health. A new book in the Methods in Molecular Biology series, Listeria monocytogenes: Methods and Protocols addresses its titular pathogen with protocols and methodologies used in research to gain a better understanding of Listeria at a molecular level. The topics covered include sampling in order to isolate Listeria, methods for their identification and characterization, methods for gene manipulation and finally, methods for control of the organism. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective subjects, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols and tips on troubleshooting and avoiding known pitfalls. Vital and authoritative, Listeria monocytogenes: Methods and Protocols aims to contribute to the harmonization of the methods used in the field and will therefore benefit all those interested in Listeria research.

Since its early days in the 1990s, the Quorum Sensing (QS) field has grown from a few dozen laboratories, investigating the pathways, proteins, and chemicals that facilitate signaling in bacteria, to hundreds of groups that have integrated evolutionary biology, computer science, mathematics, engineering, and metagenomics to create an ever-expanding and dynamic field. In Quorum Sensing: Methods and Protocols, expert researchers provide an in-depth set of diverse protocols that span this broad area of study. Broken into three detailed sections, the volume covers the detection, isolation, and characterization of the QS signals made by both Gram- and Gram+ bacteria, determination of the function of QS signals in vivo, and the development of QS disruption strategies. Written in the highly successful Methods in Molecular Biology (TM) series format, chapters include brief introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and expert tips on troubleshooting and avoiding known experimental pitfalls. Comprehensive and cutting-edge, Quorum Sensing: Methods and Protocols serves as an invaluable collection of easily accessible techniques for scientists seeking to further our knowledge about bacterial communication and its relation to humanity.

Due to the highly collaborative nature of investigators working in the field, we have rapidly advanced our understanding of Staphylococcus epidermidis and other staphylococci in the last two decades. The chapters in Staphylococcus Epidermidis: Methods and Protocols are designed to give the new investigator a series of tools so they can ask novel and exciting questions related to the biology of this opportunistic pathogen, as many exciting and unexplored questions such as defining the interaction of S. epidermidis and other normal flora remain to be discovered. Written in the successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible protocols, and notes on troubleshooting and avoiding known pitfalls. Authoritative and easily accessible, Staphylococcus Epidermidis: Methods and Protocols seeks to serve both professionals and novices with its well-honed methodologies.

Host-Bacteria Interactions: Methods and Protocols details cutting edge protocols that cover aspects of the investigation of host bacteria interactions using mammalian and novel non mammalian infection models, cell biology, OMICS and bacterial genetics. Chapters focus on techniques that can be used to investigate different aspects of the physiopathology of bacterial infections, from the whole animal to tissue, cellular and molecular level. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols and tips on troubleshooting and avoiding known pitfalls. Authoritative and cutting-edge, Host-Bacteria Interactions: Methods and Protocols provide researchers with a comprehensive account of the practical steps necessary for carrying out each protocol successfully.

This book describes the growing body of information on the epidemiology, clinical manifestations, transmission, pathogenesis, diagnosis, and treatment of Kingella kingae infections in young children. In addition, it covers experimental methods that have been developed to study the microbiology, genetics, and virulence factors of K. kingae, information that provides the foundation for new approaches to treatment and prevention of K. kingae disease. With this content in mind, excerpts from the book will be of relevance for clinicians who care for pediatric patients, for clinical microbiologists who are involved in detecting organisms in clinical specimens, and for scientists who are studying K. kingae in an effort to develop novel targets for antimicrobial therapy and new approaches to prevention. First isolated in the 1960s by Elizabeth O. King, a bacteriologist at the CDC, Kingella kingae was largely ignored over the next two decades as a human pathogen because of its uncommon recovery from patients with disease. However, in recent years K. kingae has been increasingly recognized as a clinically important pathogen in young children, and is currently recognized as the leading cause of osteoarticular infections in young children in a growing number of countries. Research into this organism has grown tremendously over the past 15 years, resulting in a better appreciation of the importance of K. kingae in pediatric patients and of the molecular mechanisms of disease.

​In recent years there has been significant attention paid on the endophytic research by various groups working within this domain. Mutualistic endophytic microbes with an emphasis on the relatively understudied fungal endophytes are the focus of this special book. Plants are associated with micro-organisms: endophytic bacteria and fungi, which live inter- and intra-cellularly without inducing pathogenic symptoms, but have active biochemical and genetic interactions with their host. Endophytes play vital roles as plant growth promoters, biocontrol agents, biosurfactant producers, enzymes and secondary metabolite producers, as well as providing a new hidden repertoire of bioactive natural products with uses in pharmaceutical, agrochemical and other biotechnological applications. The increasing interest in endophytic research generates significant progress in our understanding of the host-endophyte relationship at molecular and genetic level. The bio-prospection of microbial endophytes has led to exciting possibilities for their biotechnological application as biocontrol agent, bioactive metabolites, and other useful traits. Apart from these virtues, the microbial endophytes may be adapted to the complex metabolism of many desired molecules that can be of significant industrial applications. These microbes can be a useful alternative for sustainable solutions for ecological control of pests and diseases, and can reduce the burden of excess of chemical fertilizers for this purpose. This book is an attempt to review the recent development in the understanding of microbial endophytes and their potential biotechnological applications. This is a collection of literature authored by noted researchers having signatory status in endophytic research and summarizes the development achieved so far, and future prospects for further research in this fascinating area of research.

In recent years, molecular microbiology has emerged as a top, cutting-edge biological discipline, thanks to the multi-disciplinary and integrative approaches taken by investigators seeking to understand the intricacies of the microbial world and how it affects human health and the biosphere. In Bacterial Cell Surfaces: Methods and Protocols, recent advances in structural biology, proteomics, and imaging techniques, together with the traditional biochemical and genetic approaches, are provided in order to present an exciting look into the structure, function, and regulation of the bacterial cell envelope. The detailed volume contains examples of traditional and innovative tools for the study of protein structure and function and enzymatic activities, the purification and analysis of macromolecules and their complexes, and the investigation of regulatory mechanisms and cell biological processes. Written in the highly successful Methods in Molecular Biology (TM) series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, Bacterial Cell Surfaces: Methods and Protocols is aimed at the microbiologist, biochemist, or cell biologist, whether a beginning graduate student or a veteran experimentalist, who wishes to learn new methodologies and take advantage of the years of research and protocol optimization from the best laboratories around the world.

Bacterial genomics is a mature research interdisciplinary field, which is approached by ecologists, geneticists, bacteriologists, molecular biologists and evolutionary biologists working in medical, industrial and basic science. Thanks to the large diffusion of bacterial genome analysis, Bacterial Pangenomics: Methods and Protocols is able to provide the most recent methodologies about the study of bacterial pangenomes by covering the three major areas: the experimental methods for approaching bacterial pangenomics, the bio informatic pipelines for analysis and annotation of sequence data and finally the methods for inferring functional and evolutionary features from the pangenome. Written in the successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible protocols and notes on troubleshooting and avoiding known pitfalls. Authoritative and easily accessible, Bacterial Pangenomics: Methods and Protocols will serve as a field guide for both qualified bacterial genomics investigators who want to update their technical knowledge, for less experienced researchers who want to start working with bacterial genomics and pangenomics, as well as serving as a manual and supplemental textbook for graduate students of genomics and bioinformatics.

Microbial Products: Applications and Translational Trends offers complete coverage of the production of microbial products, including biopolymers, biofuels, bioactive compounds, and their applications in fields such as bioremediation, agriculture, medicine, and other industrial settings. This book focuses on multiple processes including upstream procedures and downstream processing, and the tools required for their production. Lab-scale development processes may not be as efficient when aiming for large-scale industrial production, so it is necessary to utilize in silico modeling tools for bioprocess design to ensure success at translational levels. Therefore, this book presents in silico and mathematical simulations and approaches used for such applications. Further, it examines microbial products produced from bacteria, fungi, and algae. These major microbial categories have the capacity to produce various, diverse secondary metabolites, bioactive compounds, enzymes, biopolymers, biofuels, probiotics, and more. The bioproducts examined in the book are of great social, medical, and agricultural benefit, and include examples of biodegradable polymers, biofuels, biofertilizers, and drug delivery agents. Presents approaches and tools that aid in the design of eco-friendly, efficient, and economic bioprocesses. Utilizes in silico and mathematical simulations for optimal bioprocess design. Examines approaches to be used for bioproducts from the lab scale to widely applied microbial biotechnologies. Presents the latest trends and technologies in the production approaches for microbial bio-products manufacture and application. This book is ideal for both researchers and academics, as it provides up-to-date knowledge of applied microbial biotechnology approaches for bio-products.

Plant microbe interaction is a complex relationship that can have various beneficial impacts on both the communities. An urgent need of today's world is to get high crop yields in an ecofriendly manner. Utilization of beneficial and multifaceted plant growth promoting (PGP) microorganisms can solve the problem of getting enhanced yields without disturbing the ecosystem thus leading to sustainability. For this to achieve understanding of the intricate details of how the beneficial microbes form associations with the host plant and sustain that for millions of years must be known. A holistic approach is required wherein the diversity of microbes associated with plant and the network of mechanisms by which they benefit the host must be studied and utilized. 'Plant Microbe Symbiosis - Fundamentals and Advances' provides a comprehensive understanding of positive interactions that occur between plant and microorganisms and their utilization in the fields. The book reviews the enormous diversity of plant associated microbes, the dialog between plant-microbes-microbes and mechanisms of action of PGP microbes. Utilization of PGPRs as nutrient providers, in combating phytopathogens and ameliorating the stressed and polluted soils is also explained. Importantly, the book also throws light on the unanswered questions and future direction of research in the field. It illustrates how the basic knowledge can be amalgamated with advanced technology to design the future bioformulations.

Streptococci are Gram-positive bacteria that cause a wide spectrum of diseases, such as pharyngitis, necrotizing fasciitis and streptococcal toxic shock syndrome, as well as rheumatic fever and rheumatic heart disease as sequelae. Antibiotics alone have not been able to control the disease and in spite of many efforts an effective vaccine is not yet available. A prerequisite for novel and successful strategies for combating these bacteria is a complete understanding of the highly complex pathogenic mechanisms involved, which are analyzed in this volume. In ten chapters, prominent authors cover various aspects including streptococcal diseases and global burden, epidemiology, adaptation and transmission, and molecular mechanisms of different diseases, as well as sequelae, vaccine development and clinical management. This book will serve as a valuable reference work for scientists, students, clinicians and public health workers and provide new approaches to meeting the challenge of streptococcal diseases.

Over the years of cancer investigation a lot of discoveries in this field were made, and many associations between various biological carcinogens and cancer were revealed. Some of them are credibly determined, thus these infectious agents (human papilloma virus, hepatitis B virus, hepatitis C virus, Epstein-Barr virus, human herpes virus 8, human T-cell lymphotropic virus 1, human immunodeficiency virus, Merkel cell polyomavirus, Helicobacter pylori, Opisthorchis viverrini, Clonorchis sinensis, Schistosoma haematobium) are recognized as carcinogens and probable carcinogens by International Agency for Research on Cancer (IARC). The problem is of large importance, since share of infectious agents-related cancer cases is steadily increasing, reaching 25% according to certain estimates. It is worth noting that many of cancer cases are caused by infectious agents other than "conventional ones" like HPV, EBV, HBV, HCV, H.pylori etc. In recent years, a number of significant breakthroughs in the field were performed, such as the discovery of the microbiota role in cancer causation.

This Brief will review the methods that are currently available for the detection, isolation, and typing of pathogenic E. coli with a particular focus on foodborne diseases caused by the Shiga toxigenic E. coli group, which have been implicated in a number of significant outbreaks in recent years. Pathogenic forms of E. coli can cause a variety of diarrheal diseases in hosts due to the presence of specific colonization and virulence factors, and pathogenicity-associated genes, which are generally not present in other E. coli. Six pathotypes of pathogenic E. coli are recognized (Shiga toxigenic E. coli, Enteropathogenic E. coli, Enterotoxigenic E. coli, Enteroinvasive E. coli, Enteroaggregative E. coli and Diffusely Adherent E. coli) and certain strains among these groups are major public health concerns due to the severity of disease that they can cause. Methods to detect and isolate these pathogens from a variety of sources are constantly evolving. In addition, the accumulation of knowledge on these pathogens allows for improved intervention strategies.

Blackwell is proud to announce Professor Barry Marshall, along with Dr. Robin Warren, have been awarded the Nobel Prize in physiology or medicine.

Providing background and the human touch of a discovery process taking almost a century, "Helicobacter Pioneers" is a collection of accounts from pioneering researchers of "Helicobacter pylori," of who had firsthand knowledge of the pioneer.

A remarkable work with original accounts that will never date, this book will inspire readers interested in gastroenterology, microbiology, or any facet of medical or scientific history.

This book offers an in-depth analysis of the cell biology of cyanobacteria, a group of phototrophic microorganisms performing an important function in the biosphere. The chapters present the author's and her colleagues' pioneering investigations of the ultrastructure of cyanobacteria under high-light and dark conditions, during irradiation by extremely high fluxes of light, in the course of L-transformation and within model associations and natural symbioses with plants. Diverse patterns of ultrastructural change are illustrated in electron micrographs and schematics. The book further introduces a new concept of "bacterial ultrastructural plasticity" - the reversible rearrangement of ultrastructure in response to environmental changes, as a strategy for finding and investigating cell adaptation mechanisms and intraspecies structural diversity of cyanobacteria and other prokaryotes. It serves as a valuable guide for teaching and research in the field of cell biology of microorganisms and plant-cyanobacteria symbioses.

The OHOLO conferences are sponsored by the Israel Institute for Biological Research and take their name from the site of the ?rst meeting on the shores of Lake Kinnereth. The purpose of these meetings is, as it was at their inception over 50 years ago, "to foster interdisciplinary communication between scientists in Israel, and to provide added stimulus by the participation of invited scientists from abroad". The core of the organizers of the OHOLO conferences are scientists from the Israel Institute for Biological Research. From time to time a particular OHOLO conference cooperates with an international scienti?c organization. The present 46th OHOLO Conference marks the resumption of the OHOLO tradition after 8 years of interruption caused by events beyond our control. It is my belief that our uncomp- mising commitment to excellence in research and development in the various areas of science in Israel is essential to our survival in this troubled region. The OHOLO conference tradition is a re?ection of this conviction. The present 46th OHOLO Conference entitled: The Challenge of Highly Pathogenic Microorganisms - Mechanisms of Virulence and Novel Medical Countermeasures intends to address the unique virulence features and ho- pathogen interactions of microorganisms constituting emerging biothreat with emphasis on Y. pestis, B. anthracis, F. tularensis and Orthopox viruses. Accordingly we selected classical microbiological as well as genomic, proteomic & transcr- tomic approaches towards developments of novel prophylactic and post-exposure treatment, as well as updated strategies of diagnostics and bioforensics.