Author: Vittorio Venturi
Publisher: Frontiers Media SA
ISBN: 2889199177
Category : Biology (General)
Languages : en
Pages : 122
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Book Description
The most common quorum sensing (QS) system in Gram-negative bacteria occurs via N-acyl homoserine lactone (AHLs) signals. An archetypical system consists of a LuxI-family protein synthesizing the AHL signal which binds at quorum concentrations to the cognate LuxR-family transcription factors which then control gene expression by binding to specific sequences in target gene promoters. QS LuxR-family proteins are approximately 250 amino acids long and made up of two domains; at the N-terminus there is an autoinducer-binding domain whereas the C-terminus contains a DNA-binding helix-turn-helix (HTH) domain. QS LuxRs display surprisingly low similarities (18-25%) even if they respond to structurally similar AHLs. 95% of LuxRs share 9 highly conserved amino acid residues; six of these are hydrophobic or aromatic and form the cavity of the AHL-binding domain and the remaining three are in the HTH domain. With only very few exceptions, the luxI/R cognate genes of AHL QS systems are located adjacent to each other. The sequencing of many bacterial genomes has revealed that many proteobacteria also possess LuxRs that do not have a cognate LuxI protein associated with them. These LuxRs have been called orphans and more recently solos. LuxR solos are widespread in proteobacterial species that possess a canonical complete AHL QS system as well as in species that do not. In many cases more than one LuxR solo is present in a bacterial genome. Scientists are beginning to investigate these solos. Are solos responding to AHL signals? If present in a bacterium which possesses a canonical AHL QS system are solos an integral part of the regulatory circuit? Are LuxR solos eavesdropping on AHLs produced by neighboring bacteria? Have they evolved to respond to different signals instead of AHLs, and are these signals endogenously produced or exogenously provided? Are they involved in interkingdom signaling by responding to eukaryotic signals? Recent studies have revealed that LuxR solos are involved in several mechanisms of cell-cell communication in bacteria implicating them in bacterial intraspecies and interspecies communication as well as in interkingdom signaling by responding to molecules produced by eukaryotes. LuxR solos are likely to become major players in signaling since they are widespread among proteobacterial genomes and because initial studies highlight their different roles in bacterial communication. This Research Topic allows scientists studying or interested in LuxR solos to report their data and/or express their hypotheses and thoughts on this important and currently understudied family of signaling proteins.
Author: Richard H. ffrench-Constant
Publisher: Springer
ISBN: 3319527150
Category : Medical
Languages : en
Pages : 212
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Book Description
This book provides an essential update on the startling array of novel insecticidal toxins and drugs produced by the fascinating bacterium Photorhabdus. The respective chapters describe everything from the detailed molecular biology of the ‘Toxin complexes’ or Tc’s to the complexity of insect immune response in relation to both the bacterium and its nematode vector. The volume covers both primary (toxin production and regulation) and secondary (natural product synthesis and regulation) metabolism and emphasises the potential use of toxins and drugs in both agriculture and medicine. It also discusses in detail two totally novel quorum sensing mechanisms and the likely role of LuxR solos in sensing the presence of different bacterial hosts. Lastly, the book explores the unique case of P. asymbiotica, which seems to have evolved the ability to infect both insects and humans. This synthesis proves that Photorhabdus truly does offer a ‘gold mine’ for the discovery of novel insecticidal proteins and novel natural products with potential uses in agriculture and medicine alike.
Author: V. Ravishankar Rai
Publisher: CRC Press
ISBN: 1000051471
Category : Science
Languages : en
Pages : 407
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Book Description
The book on Trends in Quorum Sensing and Quorum Quenching: New Perspectives and Applications focuses on the recent advances in the field of quorum sensing in bacteria and the novel strategies developed for quorum sensing inhibition. The topics covered are multidisciplinary and wide-ranging,and includes quorum sensing phenomenon in pathogenic bacteria, food spoilers, and agriculturally relevant bacteria. The applications of quorum sensing inhibitors such as small molecules, bioactives, natural compounds, and quorum quenching enzymes in controlling bacterial infections in clinical settings, agriculture and aquaculture are discussed. The potential use of quorum quenching enzymes for mitigating biofouling is also covered. Special focus is given to exploring quorum sensing inhibitors from microbes and flora inhabiting biodiversity rich regions including tropical rain forests and marine environments. Key features: Covers the fundamental aspects, the progress and challenges in the field of quorum sensing and quorum quenching Reviews quorum sensing in Gram-positive and Gram-negative bacteria of clinical, agricultural, and industrial relevance Discusses the application and future trends of quorum sensing inhibitors from lab to clinical and environmental settings Provides comprehensive coverage on molecular mechanisms in bacterial signaling
Author: Reinhard Krämer
Publisher: John Wiley & Sons
ISBN: 3527629246
Category : Science
Languages : en
Pages : 513
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Book Description
Providing a comprehensive insight into cellular signaling processes in bacteria with a special focus on biotechnological implications, this is the first book to cover intercellular as well as intracellular signaling and its relevance for biofilm formation, host pathogen interactions, symbiotic relationships, and photo- and chemotaxis. In addition, it deals in detail with principal bacterial signaling mechanisms -- making this a valuable resource for all advanced students in microbiology. Dr. Krämer is a world-renowned expert in intracellular signaling and its implications for biotechnology processes, while Dr. Jung is an expert on intercellular signaling and its relevance for biomedicine and agriculture.
Author: Pallaval Veera Bramhachari
Publisher: Springer
ISBN: 9811324298
Category : Medical
Languages : en
Pages : 377
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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.
Author: Stephen Carlyle Winans
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 528
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Book Description
Summarizes the science and recent research developments of chemical communication among bacteria
Author: Institute of Medicine
Publisher: National Academies Press
ISBN: 0309219396
Category : Science
Languages : en
Pages : 570
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Book Description
Many potential applications of synthetic and systems biology are relevant to the challenges associated with the detection, surveillance, and responses to emerging and re-emerging infectious diseases. On March 14 and 15, 2011, the Institute of Medicine's (IOM's) Forum on Microbial Threats convened a public workshop in Washington, DC, to explore the current state of the science of synthetic biology, including its dependency on systems biology; discussed the different approaches that scientists are taking to engineer, or reengineer, biological systems; and discussed how the tools and approaches of synthetic and systems biology were being applied to mitigate the risks associated with emerging infectious diseases. The Science and Applications of Synthetic and Systems Biology is organized into sections as a topic-by-topic distillation of the presentations and discussions that took place at the workshop. Its purpose is to present information from relevant experience, to delineate a range of pivotal issues and their respective challenges, and to offer differing perspectives on the topic as discussed and described by the workshop participants. This report also includes a collection of individually authored papers and commentary.
Author: Robert J. Steffan
Publisher: Springer
ISBN: 9783319504322
Category : Science
Languages : en
Pages : 0
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Book Description
In this book international experts discuss the state-of-the-art in the biological degradation of hydrocarbons to meet remedial or disposal goals. The work focuses on practical applications, often on globally important scales including the remediation of some of the world’s largest crude oil spills. Other related chapters discuss important implications of microbial transformation of hydrocarbons, including treatment of high fat processing wastes, impacts of microbial biodegradation activity on industrial processes, and the implications of microbial oil degradation in relation to modern oil extraction processes like hydraulic fracturing of shales and extraction of oil sands.
Author: Giuseppina Tommonaro
Publisher: Academic Press
ISBN: 012814906X
Category : Science
Languages : en
Pages : 312
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Book Description
Quorum sensing (QS) is a process of bacterial cooperative behaviour that has an effect on gene regulation. This cell-to-cell communication system involves the production of signalling molecules according to cell density and growth stage. Virulence, the ability to infest a habitat and cause disease, is also governed by such communication signals. Quorum Sensing: Molecular mechanism and biotechnological application collects, describes and summarizes the most interesting results obtained from experts working on QS mechanisms. It contributes to the understanding of the molecular basis that regulates this mechanism, and describes new findings in fields of application. This volume describes the QS mechanism from its molecular basis to medical applications such as antibiotic therapy and involvement of QS in pathologies. This reference also analyzes its potential use in biotechnological applications such as food packaging, drug delivery, and marine biofilm. The broad scope of this title will be of significant use to researchers across several fields with interest in QS, including to microbiologists, chemists, biochemists and ecologists. - Describes Quorum Sensing (QS) mechanisms from their molecular basis, to their clinical applications - Spans several fields in relation to QS, including microbiology, chemistry, biochemistry and ecology - Considers QS as an approach to the discovery of new antibiotics - Looks at QS as a means to understand the microbial world and towards use of bacteria and their products in biotechnological applications - Summarizes key results on QS mechanisms' molecular basis and fields of application
Author: Devendra K. Choudhary
Publisher: Springer
ISBN: 9811003882
Category : Science
Languages : en
Pages : 233
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Book Description
With a focus on food safety, this book highlights the importance of microbes in sustainable agriculture. Plants, sessile organisms that are considered as primary producers in the ecosystem and communicate with above- and below-ground communities that consist of microbes, insects, and other vertebrate and invertebrate animals, are subjected to various kinds of stress. Broadly speaking, these can be subdivided into abiotic and biotic stresses. Plants have evolved to develop elaborate mechanisms for coping with and adapting to the environmental stresses. Among other stresses, habitat-imposed biotic stress is one serious condition causing major problems for crop productivity. Most plants employ plant-growth-promoting microorganisms (PGPMs) to combat and protect themselves from stresses and also for better growth. PGPMs are bacteria associated with plant roots and they augment plant productivity and immunity. They are also defined as root-colonizing bacteria that have beneficial effects on plant growth and development. Remarkably, PGPMs including mycorrhizae, rhizobia, and rhizobacteria (Acinetobacter, Agrobacterium, Arthrobacter, Azospirillum, Bacillus, Bradyrhizobium, Frankia, Pseudomonas, Rhizobium, Serratia, Thiobacillus) form associations with plant roots and can promote plant growth by increasing plants’ access to soil minerals and protecting them against pathogens. To combat the pathogens causing different diseases and other biotic stresses, PGPMs produce a higher level of resistance in addition to plants’ indigenous immune systems in the form of induced systemic resistance (ISR). The ISR elicited by PGPMs has suppressed plant diseases caused by a range of pathogens in both the greenhouse and field. As such, the role of these microbes can no longer be ignored for sustainable agriculture. Today, PGPMs are also utilized in the form of bio-fertilizers to increase plant productivity. However, the use of PGPMs requires a precise understanding of the interactions between plants and microbes, between microbes and microbiota, and how biotic factors influence these relationships. Consequently, continued research is needed to develop new approaches to boost the efficiency of PGPMs and to understand the ecological, genetic and biochemical relationships in their habitat. The book focuses on recent research concerning interactions between PGPMs and plants under biotic stress. It addresses key concerns such as – 1. The response of benign microbes that benefit plants under biotic stress 2. The physiological changes incurred in plants under harsh conditions 3. The role of microbial determinants in promoting plant growth under biotic stress The book focuses on a range of aspects related to PGPMs such as their mode of action, priming of plant defence and plant growth in disease challenged crops, multifunctional bio-fertilizers, PGPM-mediated disease suppression, and the effect of PGPMs on secondary metabolites etc. The book will be a valuable asset to researchers and professionals working in the area of microbial-mediated support of plants under biotic stress.
