Microorganisms as Model Systems for Studying Evolution

Microorganisms as Model Systems for Studying Evolution PDF Author: Robert Mortlock
Publisher: Springer Science & Business Media
ISBN: 1468448447
Category : Science
Languages : en
Pages : 338

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Book Description
The microorganisms present on the earth today possess a vast range of metabolic activities and are often able to demonstrate their surprising versatility by gaining both new enzyme activities and new metabolic path ways through mutations. It is generally assumed that the earliest micro organisms were very limited in their metabolic abilities, but as time passed they gradually expanded their range of enzymatic activities and increased both their biosynthetic and catabolic capacity. It is also believed that these primitive microorganisms increased the amount of genetic material they possessed by duplicating their existing genes and possibly by ac quiring genetic material from other organisms. A small group of scientists has been exploring the means by which existing microorganisms are capable of mutating to expand their bio chemical abilities. In recent years, more attention has been focused on this type of research, sometimes called "evolution in a test tube." The recent advances in biotechnology and modern techniques of genetic trans fer have generated new interest in the methods by which a microorgan ism's metabolic activities can be improved or deliberately changed in some specific manner.

Microorganisms as Model Systems for Studying Evolution

Microorganisms as Model Systems for Studying Evolution PDF Author: Robert Mortlock
Publisher: Springer Science & Business Media
ISBN: 1468448447
Category : Science
Languages : en
Pages : 338

Get Book Here

Book Description
The microorganisms present on the earth today possess a vast range of metabolic activities and are often able to demonstrate their surprising versatility by gaining both new enzyme activities and new metabolic path ways through mutations. It is generally assumed that the earliest micro organisms were very limited in their metabolic abilities, but as time passed they gradually expanded their range of enzymatic activities and increased both their biosynthetic and catabolic capacity. It is also believed that these primitive microorganisms increased the amount of genetic material they possessed by duplicating their existing genes and possibly by ac quiring genetic material from other organisms. A small group of scientists has been exploring the means by which existing microorganisms are capable of mutating to expand their bio chemical abilities. In recent years, more attention has been focused on this type of research, sometimes called "evolution in a test tube." The recent advances in biotechnology and modern techniques of genetic trans fer have generated new interest in the methods by which a microorgan ism's metabolic activities can be improved or deliberately changed in some specific manner.

Systems Microbiology

Systems Microbiology PDF Author: Brian Douglas Robertson
Publisher:
ISBN: 9781912530458
Category : Biological models
Languages : en
Pages : 0

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Book Description
This volume contains cutting-edge reviews by world-leading experts on the systems biology of microorganisms. As well as covering theoretical approaches and mathematical modelling this book includes case studies on single microbial species of bacteria and archaea, and explores the systems analysis of microbial phenomena such as chemotaxis and phagocytosis. Topics covered include mathematical models for systems biology, systems biology of Escherichia coli metabolism, bacterial chemotaxis, systems biology of infection, host-microbe interactions, phagocytosis, system-level study of metabolism in M.

Microbial Evolution under Extreme Conditions

Microbial Evolution under Extreme Conditions PDF Author: Corien Bakermans
Publisher: Walter de Gruyter GmbH & Co KG
ISBN: 3110340712
Category : Nature
Languages : en
Pages : 290

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Book Description
Today's microorganisms represent the vast majority of biodiversity on Earth and have survived nearly 4 billion years of evolutionary change. However, we still know little about the processes of evolution as applied to microorganisms and microbial populations. Microbial evolution occurred and continues to take place in a vast variety of environmental conditions that range from anoxic to oxic, from hot to cold, from free-living to symbiotic, etc. Some of these physicochemical conditions are considered "extreme", particularly when inhabitants are limited to microorganisms. It is easy to imagine that microbial life in extreme environments is somehow more constrained and perhaps subjected to different evolutionary pressures. But what do we actually know about microbial evolution under extreme conditions and how can we apply that knowledge to other conditions? Appealingly, extreme environments with their relatively limited numbers of inhabitants can serve as good model systems for the study of evolutionary processes. A look at the microbial inhabitants of today's extreme environments provides a snapshot in time of evolution and adaptation to extreme conditions. These adaptations manifest at different levels from established communities and species to genome content and changes in specific genes that result in altered function or gene expression. But as a recent (2011) report from the American Academy of Microbiology observes: "A complex issue in the study of microbial evolution is unraveling the process of evolution from that of adaptation. In many cases, microbes have the capacity to adapt to various environmental changes by changing gene expression or community composition as opposed to having to evolve entirely new capabilities." We have learned much about how microbes are adapted to extreme conditions but relatively little is known about these adaptations evolved. How did the different processes of evolution such as mutation, immigration, horizontal (lateral) gene transfer, recombination, hybridization, genetic drift, fixation, positive and negative selection, and selective screens contribute to the evolution of these genes, genomes, microbial species, communities, and functions? What are typical rates of these processes? How prevalent are each of these processes under different conditions? This book explores the current state of knowledge about microbial evolution under extreme conditions and addresses the following questions: What is known about the processes of microbial evolution (mechanisms, rates, etc.) under extreme conditions? Can this knowledge be applied to other systems and what is the broader relevance? What remains unknown and requires future research? These questions will be addressed from several perspectives including different extreme environments, specific organisms, and specific evolutionary processes.

Microbial Evolution

Microbial Evolution PDF Author: Howard Ochman
Publisher:
ISBN: 9781621820376
Category : Science
Languages : en
Pages : 0

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Book Description
Bacteria have been the dominant forms of life on Earth for the past 3.5 billion years. They rapidly evolve, constantly changing their genetic architecture through horizontal DNA transfer and other mechanisms. Consequently, it can be difficult to define individual species and determine how they are related. Written and edited by experts in the field, this collection from Cold Spring Harbor Perspectives in Biology examines how bacteria and other microbes evolve, focusing on insights from genomics-based studies. Contributors discuss the origins of new microbial populations, the evolutionary and ecological mechanisms that keep species separate once they have diverged, and the challenges of constructing phylogenetic trees that accurately reflect their relationships. They describe the organization of microbial genomes, the various mutations that occur, including the birth of new genes de novo and by duplication, and how natural selection acts on those changes. The role of horizontal gene transfer as a strong driver of microbial evolution is emphasized throughout. The authors also explore the geologic evidence for early microbial evolution and describe the use of microbial evolution experiments to examine phenomena like natural selection. This volume will thus be essential reading for all microbial ecologists, population geneticists, and evolutionary biologists.

Variation and Evolution in Plants and Microorganisms

Variation and Evolution in Plants and Microorganisms PDF Author: National Academy of Sciences
Publisher: National Academies Press
ISBN: 0309172268
Category : Science
Languages : en
Pages : 353

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Book Description
"The present book is intended as a progress report on [the] synthetic approach to evolution as it applies to the plant kingdom." With this simple statement, G. Ledyard Stebbins formulated the objectives of Variation and Evolution in Plants, published in 1950, setting forth for plants what became known as the "synthetic theory of evolution" or "the modern synthesis." The pervading conceit of the book was the molding of Darwin's evolution by natural selection within the framework of rapidly advancing genetic knowledge. At the time, Variation and Evolution in Plants significantly extended the scope of the science of plants. Plants, with their unique genetic, physiological, and evolutionary features, had all but been left completely out of the synthesis until that point. Fifty years later, the National Academy of Sciences convened a colloquium to update the advances made by Stebbins. This collection of 17 papers marks the 50th anniversary of the publication of Stebbins' classic. Organized into five sections, the book covers: early evolution and the origin of cells, virus and bacterial models, protoctist models, population variation, and trends and patterns in plant evolution.

Concepts of Biology

Concepts of Biology PDF Author: Samantha Fowler
Publisher:
ISBN: 9781739015503
Category :
Languages : en
Pages : 0

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Book Description
Black & white print. Concepts of Biology is designed for the typical introductory biology course for nonmajors, covering standard scope and sequence requirements. The text includes interesting applications and conveys the major themes of biology, with content that is meaningful and easy to understand. The book is designed to demonstrate biology concepts and to promote scientific literacy.

The Hologenome Concept: Human, Animal and Plant Microbiota

The Hologenome Concept: Human, Animal and Plant Microbiota PDF Author: Eugene Rosenberg
Publisher: Springer Science & Business Media
ISBN: 3319042416
Category : Science
Languages : en
Pages : 187

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Book Description
Groundbreaking research over the last 10 years has given rise to the hologenome concept of evolution. This concept posits that the holobiont (host plus all of its associated microorganisms) and its hologenome (sum of the genetic information of the host and its symbiotic microorganisms), acting in concert, function as a unique biological entity and therefore as a level of selection in evolution. All animals and plants harbor abundant and diverse microbiota, including viruses. Often the amount of symbiotic microorganisms and their combined genetic information far exceed that of their host. The microbiota with its microbiome, together with the host genome, can be transmitted from one generation to the next and thus propagate the unique properties of the holobiont. The microbial symbionts and the host interact in a cooperative way that affects the health of the holobiont within its environment. Beneficial microbiota protects against pathogens, provides essential nutrients, catabolizes complex polysaccharides, renders harmful chemicals inert, and contributes to the performance of the immune system. In humans and animals, the microbiota also plays a role in behavior. The sum of these cooperative interactions characterizes the holobiont as a unique biological entity. Genetic variation in the hologenome can be brought about by changes in either the host genome or the microbial population genomes (microbiome). Evolution by cooperation can occur by amplifying existing microbes, gaining novel microbiota and by acquiring microbial and viral genes. Under environmental stress, the microbiome can change more rapidly and in response to more processes than the host organism alone and thus influences the evolution of the holobiont. Prebiotics, probiotics, synbiotics and phage therapy are discussed as applied aspects of the hologenome concept.

The Chemistry of Microbiomes

The Chemistry of Microbiomes PDF Author: National Academies of Sciences, Engineering, and Medicine
Publisher: National Academies Press
ISBN: 0309458390
Category : Science
Languages : en
Pages : 133

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Book Description
The 21st century has witnessed a complete revolution in the understanding and description of bacteria in eco- systems and microbial assemblages, and how they are regulated by complex interactions among microbes, hosts, and environments. The human organism is no longer considered a monolithic assembly of tissues, but is instead a true ecosystem composed of human cells, bacteria, fungi, algae, and viruses. As such, humans are not unlike other complex ecosystems containing microbial assemblages observed in the marine and earth environments. They all share a basic functional principle: Chemical communication is the universal language that allows such groups to properly function together. These chemical networks regulate interactions like metabolic exchange, antibiosis and symbiosis, and communication. The National Academies of Sciences, Engineering, and Medicine's Chemical Sciences Roundtable organized a series of four seminars in the autumn of 2016 to explore the current advances, opportunities, and challenges toward unveiling this "chemical dark matter" and its role in the regulation and function of different ecosystems. The first three focused on specific ecosystemsâ€"earth, marine, and humanâ€"and the last on all microbiome systems. This publication summarizes the presentations and discussions from the seminars.

Diversity of the Microbial World

Diversity of the Microbial World PDF Author: Angélica Cibrián-Jaramillo
Publisher: Frontiers Media SA
ISBN: 2889636658
Category :
Languages : en
Pages : 86

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Book Description
Microbes, or microorganisms, are tiny living beings that cannot be seen by the naked eye. These little guys are one of the oldest living things on Earth, and are extremely diverse in how they live and what they can do. They, for example, can live in many places, from the freezing iciness of glaciers, to the insides of other organisms, like termites or humans. Since they are virtually everywhere, microorganisms are essential for the biological processes that allow plants and animals to breath, eat and thrive. But how were they able to endure, adapt and flourish constantly over millions of years? The secrets of their success are still within them, coded into their genomes, waiting for us to understand them. Now, genomes, bacterial or otherwise, are the repositories of life. These repositories store almost every bit of information that allows living beings to live in discrete units called genes. Genes are strung together like the sentences in a book, interacting with each other to create meaning, saving the story of that particular book—or that particular living organism’s genome—so it can be copied, modified, corrected or enhanced, and then passed on to new generations. After many, many years of studying these “books,” we have learned to read and understand them, thanks to the technological innovations of the last decade. Nowadays, it is possible to get the full genomic sequence of practically any organism, and compare it with thousands of genomes from other organisms, letting us peek at the secrets that make each organism who it is. With the current technical abilities, the challenge now is not to obtain the information but to interpret all those chunks of the story. Finding ways to untangle the riddles of genomic information is the work of Genomics, the science that allows us to obtain, analyze and prioritize information among the many stories that we sequence everyday. To do this, Genomics draws from many sciences, like mathematics and computing sciences, making it a truly interdisciplinary endeavor. Right now , genomics are one of the most important areas of biology, and many, if not most, of current biological studies use at least a little bit of genomics. For example, genomics can be used to identify a microbe and give it a name, to learn about what types of things it can do or places it can live, and to figure out the mechanisms that enable it to survive under particular conditions. Here, we will dwell on some of the basic questions about microbial adaptation, biodiversity, and their relationships with other living beings using a genomic approach. We will also focus on the environment, trying to understand how such tiny little creatures are capable of solving their daily problems, and how they can alter the places in which they live. Learning about these mechanisms will not only provide us with knowledge about life in general but will also help us to understand these organisms as a fundamental component of our ecosystem, including their harmful and beneficial effects in all aspects of our daily life, which can be translated into useful applications in almost any imaginable way.

Teaching About Evolution and the Nature of Science

Teaching About Evolution and the Nature of Science PDF Author: National Academy of Sciences
Publisher: National Academies Press
ISBN: 0309063647
Category : Education
Languages : en
Pages : 150

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Book Description
Today many school students are shielded from one of the most important concepts in modern science: evolution. In engaging and conversational style, Teaching About Evolution and the Nature of Science provides a well-structured framework for understanding and teaching evolution. Written for teachers, parents, and community officials as well as scientists and educators, this book describes how evolution reveals both the great diversity and similarity among the Earth's organisms; it explores how scientists approach the question of evolution; and it illustrates the nature of science as a way of knowing about the natural world. In addition, the book provides answers to frequently asked questions to help readers understand many of the issues and misconceptions about evolution. The book includes sample activities for teaching about evolution and the nature of science. For example, the book includes activities that investigate fossil footprints and population growth that teachers of science can use to introduce principles of evolution. Background information, materials, and step-by-step presentations are provided for each activity. In addition, this volume: Presents the evidence for evolution, including how evolution can be observed today. Explains the nature of science through a variety of examples. Describes how science differs from other human endeavors and why evolution is one of the best avenues for helping students understand this distinction. Answers frequently asked questions about evolution. Teaching About Evolution and the Nature of Science builds on the 1996 National Science Education Standards released by the National Research Councilâ€"and offers detailed guidance on how to evaluate and choose instructional materials that support the standards. Comprehensive and practical, this book brings one of today's educational challenges into focus in a balanced and reasoned discussion. It will be of special interest to teachers of science, school administrators, and interested members of the community.