Quorum Sensing vs Quorum Quenching: A Battle with No End in Sight


Book Description

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?




Implication of Quorum Sensing System in Biofilm Formation and Virulence


Book Description

This book illustrates the importance and significance of Quorum sensing (QS), it’s critical roles in regulating diverse cellular functions in microbes, including bioluminescence, virulence, pathogenesis, gene expression, biofilm formation and antibiotic resistance. Microbes can coordinate population behavior with small molecules called autoinducers (AHL) which serves as a signal of cellular population density, triggering new patterns of gene expression for mounting virulence and pathogenesis. Therefore, these microbes have the competence to coordinate and regulate explicit sets of genes by sensing and communicating amongst themselves utilizing variety of signals. This book descry emphasizes on how bacteria can coordinate an activity and synchronize their response to external signals and regulate gene expression. The chapters of the book provide the recent advancements on various functional aspects of QS systems in different gram positive and gram negative organisms. Finally, the book also elucidates a comprehensive yet a representative description of a large number of challenges associated with quorum sensing signal molecules viz. virulence, pathogenesis, antibiotic synthesis, biosurfactants production, persister cells, cell signaling and biofilms, intra and inter-species communications, host-pathogen interactions, social interactions & swarming migration in biofilms.




Molecular Ecology of Rhizosphere Microorganisms


Book Description

This book helps evaluate the state of the art of rhizosphere microbial ecology and biotechnology. Experts in the field review methods and strategies applied to the detection, identification and monitoring of microorganisms in the rhizosphere. Major topics treated include: - construction of genetically marked rhizosphere bacteria - detection of marked wildtype and genetically modified organisms (GMOs) - identification of wildtype and GMOs by DNA probes and PCR amplification - rapid typing of non-modified and GMOs by PCR-based techniques - assessment of the role of gene transfer - EU regulations for the use and release of GMOs - biosafety results from field testing of GMOs In addition, technologies for the modifying gene expression and gene products for specific traits of agronomic interest in genetically engineered rhizosphere bacteria are covered.




Microbial Endocrinology


Book Description

Microbial endocrinology represents a newly emerging interdisciplinary field that is formed by the intersection of the fields of neurobiology and microbiology. This book will introduce a new perspective to the current understanding not only of the factors that mediate the ability of microbes to cause disease, but also to the mechanisms that maintain normal homeostasis. The discovery that microbes can directly respond to neuroendocrine hormones, as evidenced by increased growth and production of virulence-associated factors, provides for a new framework with which to investigate how microorganisms interface not only with vertebrates, but also with invertebrates and even plants. The reader will learn that the neuroendocrine hormones that one most commonly associates with mammals are actually found throughout the plant, insect and microbial communities to an extent that will undoubtedly surprise many, and most importantly, how interactions between microbes and neuroendocrine hormones can influence the pathophysiology of infectious disease.




Bacterial Physiology


Book Description

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.




Chemical Communication Among Bacteria


Book Description

Summarizes the science and recent research developments of chemical communication among bacteria




Biosurfactants


Book Description

Biosurfactants, tensio-active compounds produced by living cells, are now gaining increasing interest due to their potential applications in many different industrial areas in which to date almost exclusively synthetic surfactants have been used. Their unique structures and characteristics are just starting to be appreciated. In addition, biosurfactants are considered to be environmentally “friendly,” relatively non-toxic and biodegradable. This Microbiology Monographs volume deals with the most recent advances in the field of microbial biosurfactants, such as rhamnolipids, serrawettins, trehalolipids, mannosylerythritol lipids, sophorolipids, surfactin and other lipopeptides. Each chapter reviews the characteristics of an individual biosurfactant including the physicochemical properties, the chemical structures, the role in the physiology of the producing microbes, the biosynthetic pathways, the genetic regulation, and the potential biotechnological applications.




Modern Microbial Genetics


Book Description

In accordance with its predecessor, the completely revised and expanded Second Edition of Modern Microbial Genetics focuses on how bacteria and bacteriophage arrange and rearrange their genetic material through mutation, evolution, and genetic exchange to take optimal advantage of their environment. The text is divided into three sections: DNA Metabolism, Genetic Response, and Genetic Exchange. The first addresses how DNA replicates, repairs itself, and recombines, as well as how it may be manipulated. The second section is devoted to how microorganisms interact with their environment, including chapters on sporulation and stress shock, and the final section contains the latest information on classic exchange mechanisms such as transformation and conjugation. Chapters include: * Gene Expression and Its Regulation * Single-Stranded DNA Phages * Genetic Tools for Dissecting Motility and Development of Myxococcus xanthus * Molecular Mechanism of Quorum Sensing * Transduction in Gram-Negative Bacteria * Genetic Approaches in Bacteria with No Natural Genetic Systems The editors also cultivate an attention to global regulatory systems throughout the book, elucidating how certain genes and operons in bacteria, defined as regulons, network and cooperate to suit the needs of the bacterial cell. With clear appreciation for the impact of molecular genomics, this completely revised and updated edition proves that Modern Microbial Genetics remains the benchmark text in its field.




Model Organisms for Microbial Pathogenesis, Biofilm Formation and Antimicrobial Drug Discovery


Book Description

This book provides essential insights into microbial pathogenesis, host-pathogen interactions, and the anti-microbial drug resistance of various human pathogens on the basis of various model organisms. The initial sections of the book introduce readers to the mechanisms of microbial pathogenesis, host-pathogen interactions, anti-microbial drug resistance, and the dynamics of biofilm formation. Due to the emergence of various microbial resistant strains, it is especially important to understand the prognosis for microbial infections, disease progression profiles, and mechanisms of resistance to antibiotic therapy in order to develop novel therapeutic strategies. In turn, the second part of the book presents a comparative analysis of various animal models to help readers understand microbial pathogenesis, host-pathogen interactions, anti-microbial drug discovery, anti-biofilm therapeutics, and treatment regimes. Given its scope, the book represents a valuable asset for microbiologists, biotechnologists, medical professionals, drug development researchers, and pharmacologists alike.




Bacterial Biofilms


Book Description

This book examines biofilms in nature. Organized into four parts, this book addresses biofilms in wastewater treatment, inhibition of biofilm formation, biofilms and infection, and ecology of biofilms. It is designed for clinicians, researchers, and industry professionals in the fields of microbiology, biotechnology, ecology, and medicine as well as graduate and postgraduate students.