Author: Michele M. OttePublisher:
ISBN:
Category :
Languages : en
Pages : 180
Book Description
Analysis of Enzymes of the Late Steps of Coenzyme B12 Biosynthesis in Archaea and Bacteria
Author: Michele M. OtteBiosynthesis of the Aminopropanol Moiety of Cobamides by Bacterial and Archaeal Enzymes
Author: Norbert Keith TavaresPublisher:
ISBN:
Category :
Languages : en
Pages : 312
Book Description
Adenosylcobalamin (Coenzyme B12, AdoCbl) is a cofactor that is essential for organisms in all three domains of life, but is only synthesized by bacteria and archaea. While much is known about the biosynthesis of AdoCbl, many gaps remain. There is a separate aerobic and anaerobic pathway for the synthesis of the corrinoid ring of AdoCbl. These pathways involve a different set of enzymes and exist separately in different prokaryotic organisms. The pathways converge with the late steps where homologous enzymes carry out several, but not all steps. The late steps of the anaerobic pathway has been well studies in Salmonella enterica sv Typhimurium LT2. Homologous enzymes have not been identified for some of the late steps of the aerobic pathway, or within archaea or hyperthermophiles, which use the anaerobic pathway. Among these yet-to-be identified enzymes are the Adenosylcobalamin-5'-phosphate phosphatase (EC 3.1.3.73) (CobC in S. Typhimurium, CobZ in archaea), which catalyze the final step, and the L-threonine kinase (EC 2.7.1.177) (PduX in S. Typhimurium), which catalyzes the first step in the synthesis of the 1-amino-2-propanol-O-2-phosphate (AP-P) nucleotide linker moiety of AdoCbl. Here we identify an enzyme named BluE, a L-threonine (L-Thr) kinase in Rhodobacter sphaeroides, an organism that synthesizes AdoCbl via the aerobic pathway. We show that RsBluE has L-Thr kinase activity in vitro and complements a S. Typhimurium pduX strain in vivo. Phylogenic analysis of bluE shows it is restricted to a few Rhodobacterales that have a strict requirement for the cobalamin with 5,6-dimethylbenzimidazole as the lower ligand and AP-P as the nucleotide linker. To date no archaeal genomes have been found to encode pduX or bluE homologues. Investigations of the unusual archaeal L-threonine-O-3-phosphate (L-Thr-P) decarboxylase (CobD, EC 4.1.1.81) from Methanosarcina mazei revealed that this enzyme is bifunctional, conferring L-Thr kinase activity in addition to the expected L-Thr-P decarboxylation. MmCobD has a [4Fe-4S]2+ cluster domain that appears to have a regulatory function for both enzymatic activities. Bioinformatics analyses suggest that many organisms that lack pduX or bluE homologues encode a CobD with a slightly longer N-terminus similar to that of MmCobD. This region might encode all or part of a motif for the L-Thr kinase activity.
Coenzyme B12 Biosynthesis and Precursor Salvaging in Archaea
Author: Jesse Daniel WoodsonPublisher:
ISBN:
Category :
Languages : en
Pages : 324
Book Description
The Prokaryotes
Author: Edward F. DeLongPublisher: Springer
ISBN: 9783642301193
Category : Science
Languages : en
Pages : 567
Book Description
The Prokaryotes is a comprehensive, multi-authored, peer reviewed reference work on Bacteria and Achaea. This fourth edition of The Prokaryotes is organized to cover all taxonomic diversity, using the family level to delineate chapters. Different from other resources, this new Springer product includes not only taxonomy, but also prokaryotic biology and technology of taxa in a broad context. Technological aspects highlight the usefulness of prokaryotes in processes and products, including biocontrol agents and as genetics tools. The content of the expanded fourth edition is divided into two parts: Part 1 contains review chapters dealing with the most important general concepts in molecular, applied and general prokaryote biology; Part 2 describes the known properties of specific taxonomic groups. Two completely new sections have been added to Part 1: bacterial communities and human bacteriology. The bacterial communities section reflects the growing realization that studies on pure cultures of bacteria have led to an incomplete picture of the microbial world for two fundamental reasons: the vast majority of bacteria in soil, water and associated with biological tissues are currently not culturable, and that an understanding of microbial ecology requires knowledge on how different bacterial species interact with each other in their natural environment. The new section on human microbiology deals with bacteria associated with healthy humans and bacterial pathogenesis. Each of the major human diseases caused by bacteria is reviewed, from identifying the pathogens by classical clinical and non-culturing techniques to the biochemical mechanisms of the disease process. The 4th edition of The Prokaryotes is the most complete resource on the biology of prokaryotes. The following volumes are published consecutively within the 4th Edition: Prokaryotic Biology and Symbiotic Associations Prokaryotic Communities and Ecophysiology Prokaryotic Physiology and Biochemistry Applied Bacteriology and Biotechnology Human Microbiology Actinobacteria Firmicutes Alphaproteobacteria and Betaproteobacteria Gammaproteobacteria Deltaproteobacteria and Epsilonproteobacteria Other Major Lineages of Bacteria and the Archaea
Probiotics and Prebiotics in Human Nutrition and Health
Author: Venketeshwer RaoPublisher: BoD – Books on Demand
ISBN: 9535124757
Category : Medical
Languages : en
Pages : 396
Book Description
Probiotic microorganisms are recognised as being beneficial for human health. Prebiotics are substrates that are used preferentially by the probiotic bacteria for their growth. A great deal of interest has been generated in recent years in identifying probiotic bacteria and prebiotics, their characterization, mechanisms of action and their role in the prevention and management of human health disorders. Together they are referred to as synbiotic. This book is in response to the need for more current and global scope of probiotics and prebiotics. It contains chapters written by internationally recognized authors. The book has been planned to meet the needs of the researchers, health professionals, government regulatory agencies and industries. This book will serve as a standard reference book in this important and fast-growing area of probiotics and prebiotics in human nutrition and health.
Methanogenesis
Author: James G. FerryPublisher: Springer Science & Business Media
ISBN: 1461523915
Category : Science
Languages : en
Pages : 541
Book Description
Since the general recognition of the Archaebacteria, research into the evolution, metabolism, molecular biology and ecological roles of these fastidious anaerobes has proceeded at an ever-increasing pace. All possess a very novel biochemistry and many exploit unique ecological niches. Methanogens, which convert one-and-two carbon compounds into the important atmospheric gas methane, are the largest group among the Archaebacteria. Of all microbial groups, methanogens provide perhaps the best opportunity to study evolution because of their phyologenetic diversity and unique biochemistry. Today, the analysis of methanogens is at a threshold. Molecular-biological studies of these microorganisms are revealing more and more processes unique to this group, and in turn, studies of methanogens are providing new perspectives to the broader fields of biochemistry and molecular biology. This volume is the first book to be published on methanogenesis, and it will provide the reader with a comprehensive view of the field and point to future trends.
Prokaryotic Metabolism and Physiology
Author: Byung Hong KimPublisher: Cambridge University Press
ISBN: 1107171733
Category : Medical
Languages : en
Pages : 509
Book Description
Extensive and up-to-date review of key metabolic processes in bacteria and archaea and how metabolism is regulated under various conditions.
Organohalide-Respiring Bacteria
Author: Lorenz AdrianPublisher: Springer
ISBN: 3662498758
Category : Science
Languages : en
Pages : 620
Book Description
This book summarizes the current state of knowledge concerning bacteria that use halogenated organic compounds as respiratory electron acceptors. The discovery of organohalide-respiring bacteria has expanded the range of electron acceptors used for energy conservation, and serves as a prime example of how scientific discoveries are enabling innovative engineering solutions that have transformed remediation practice. Individual chapters provide in-depth background information on the discovery, isolation, phylogeny, biochemistry, genomic features, and ecology of individual organohalide-respiring genera, including Dehalococcoides, Dehalogenimonas, Dehalobacter, Desulfitobacterium and Sulfurospirillum, as well as organohalide-respiring members of the Deltaproteobacteria. The book introduces readers to the fascinating biology of organohalide-respiring bacteria, offering a valuable resource for students, engineers and practitioners alike.
Binding, Transport and Storage of Metal Ions in Biological Cells
Author: Wolfgang MaretPublisher: Royal Society of Chemistry
ISBN: 1782622829
Category : Science
Languages : en
Pages : 990
Book Description
Metal ions play key roles in biology. Many are essential for catalysis, for electron transfer and for the fixation, sensing, and metabolism of gases. Others compete with those essential metal ions or have toxic or pharmacological effects. This book is structured around the periodic table and focuses on the control of metal ions in cells. It addresses the molecular aspects of binding, transport and storage that ensure balanced levels of the essential elements. Organisms have also developed mechanisms to deal with the non-essential metal ions. However, through new uses and manufacturing processes, organisms are increasingly exposed to changing levels of both essential and non-essential ions in new chemical forms. They may not have developed defenses against some of these forms (such as nanoparticles). Many diseases such as cancer, diabetes and neurodegeneration are associated with metal ion imbalance. There may be a deficiency of the essential metals, overload of either essential or non-essential metals or perturbation of the overall natural balance. This book is the first to comprehensively survey the molecular nature of the overall natural balance of metal ions in nutrition, toxicology and pharmacology. It is written as an introduction to research for students and researchers in academia and industry and begins with a chapter by Professor R J P Williams FRS.
B Group Vitamins
Author: Jean Guy LeBlancPublisher: BoD – Books on Demand
ISBN: 1789239893
Category : Science
Languages : en
Pages : 156
Book Description
B-group vitamins are involved in numerous metabolic reactions and their widespread deficiency can cause a large series of health problems. The aim of this book is to provide an update on the current use and perspectives of B-group vitamins. Novel methods to detect folates in pregnant women, the use and role of folate dentistry, the use of genotype notification to modify food intake behavior, thiamin metabolism in Archaea and its role in plants and in crop improvement, the use of riboflavin in blood safety and niacin in metabolic stress and resistance in dairy cows are some of the subjects that are described in this multitopic book written by authors from seven different countries.