DOCSLIB.ORG

Foundations of Microbiology 51

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Foundations of Microbiology 51 © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION Cells of Vibrio cholerae, transmitted to humans in contaminated water and food, are the cause of cholera. Courtesy of CDC. PART Foundations of Microbiology 51 CHAPTER 1 Microbiology: Then and Now CHAPTER 2 The Chemical Building Blocks of Life CHAPTER 3 Concepts and Tools for Studying Microorganisms CHAPTER 4 Structure of Bacterial and Archaeal Cells CHAPTER 5 Microbial Growth and Nutrition CHAPTER 6 Microbial Metabolism CHAPTER 7 Control of Microorganisms: Physical and Chemical Methods n 1676, a century before the Declaration of Independence, a Dutch merchant named Antony van Leeuwenhoek sent a noteworthy letter to the Royal Society of London. Writing in the vernacular of his home in the United Netherlands, I Leeuwenhoek described how he used a simple microscope to observe vast populations of minute, living creatures. His reports opened a chapter of science that would evolve into the study of microscopic organisms and the discipline of microbiology. During the next three centuries scientists would discover how profoundly these organisms influence the quality of our lives and the environment around us. We begin our study of the microorganisms by exploring the grassroot developments that led to the establishment of microbiology as a science. These developments are surveyed in Chapter 1, where we focus on some of the individuals who stood at the forefront of discovery. Today we are in the midst of a third Golden Age of microbiology and our understanding of microorganisms continues to grow even as you read this book. Chapter 2 reviews basic chemistry, inasmuch as microbial growth, metabolism, and control are grounded in the molecules and macromolecules these organisms contain and in the biological processes they undergo. Chapter 3 sets down some basic microbiological concepts and describes one of the major tools for studying microorganisms. We will concentrate on the bacterial organisms in Chapter 4, where we survey their structural frameworks. In Chapter 5, we build on these frameworks by examining microbial growth patterns and nutritional requirements. Chapter 6 describes the metabolism of microbial cells, including those chemical reactions that produce and use energy. Part 1 concludes by considering the physical and chemical methods used to control microbial growth and metabolism (Chapter 7). Much as the alphabet applies to word development, in each succeeding chapter we will formulate words into sentences and sentences into ideas as we construct an understanding of microorganisms and concentrate on their importance to public health and human welfare. 3RD PAGES © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION MICROBIOLOGY PATHWAYS Being a Scientist Science may not seem like the most glamorous profession. So, as you read many of the chapters in this text, you might wonder why many scientists have the good fortune to make key discoveries. At times, it might seem like it is the luck of the draw, but actually many scientists have a set of characteristics that put them on the trail to success. Robert S. Root-Bernstein, a physiology professor at Michigan State University, points out that many prominent scientists like to goof around, play games, and surround themselves with a type of chaos aimed at revealing the unexpected. Their labs may appear to be in disorder, but they know exactly where every tube or bottle belongs. Scientists also identify intimately with the organisms or creatures they study (it is said that Louis Pasteur actually dreamed about microorganisms), and this identification brings on an intuition—a “feeling for the organism.” In addition, there is the ability to recognize patterns that might bring a breakthrough. (Pasteur had studied art as a teenager and, therefore, he had an appreciation of patterns.) © Comstock/Thinkstock. The geneticist and Nobel laureate Barbara McClintock once remarked, “I was just so interested in what I was doing I could hardly wait to get up in the morning and get at it. One of my friends, a geneticist, said I was a child, because only children can’t wait to get up in the morning to get at what they want to do.” Clearly, another characteristic of a scientist is having a child- like curiosity for the unknown. Another Nobel laureate and immunologist, Peter Medawar, once said “Scientists are people of very dissimilar temperaments doing different things in very different ways. Among scientists are collectors, classifiers, and compulsive tidiers-up; many are detectives by temperament and many are explorers; some are artists and others artisans. There are poet-scientists and philosopher-scientists and even a few mystics.” In other words, scientists come from all walks of life. For this author, I too have found science to be an extraordinary opportunity to discover and understand something never before known. Science is fun, yet challenging—and at times arduous, tedious, and frustrating. As with most of us, we will not make the headlines for a breakthrough discovery or find a cure for a disease. However, as scientists we all hope our hard work and achievements will contribute to a better understanding of a biological (or microbiological) phenomenon and will push back the frontiers of knowledge and have a positive impact on society. Like any profession, being a scientist is not for everyone. Besides having a bachelor’s degree in biology or microbiology, you should be well read in the sciences and capable of working as part of an interdisciplinary team. Of course, you should have good quantitative and communication skills, have an inquisitive mind, and be goal oriented. If all this sounds interesting, then maybe you fit the mold of a scientist. Why not consider pursuing a career in microbiology? Some possibilities are described in other Microbiology Pathways included in this book, but you should also visit with your instructor. Simply stop by the student union, buy two cups of coffee, and you are on your way. 3RD PAGES © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION 1 CHAPTER PREVIEW 1.1 The Discovery of Microbes Leads Microbiology: to Questioning Their Origins Investigating the Microbial World 1: Can Life Arise Spontaneously? MICROINQUIRY 1: Experimentation and Then and Now Scientific Inquiry 1.2 Disease Transmission Can Be Interrupted Microorganisms account for most of the biomass on the planet and are an essential foundation on which the global ecosystem rests. They play 1.3 The Classical Golden Age of an absolutely essential role in the survival of the human race. Microbiology Reveals the Germ —Carl Woese (Professor of Microbiology, University of Illinois at 1.4 With the Discovery of Other Microbes, Urbana-Champaign) the Microbial World Expands Space. The final frontier! Really?The final frontier? There are an esti- 1.5 A Second Golden Age of Microbiology 23 Involves the Birth of Molecular mated 350 billion large galaxies and more than 10 stars in the visible Biology and Chemotherapy universe. However, the invisible microbial universe consists of more than 1030 microorganisms (or microbes for short) scattered among an esti- 1.6 The Third Golden Age of Microbiology mated 2 to 3 billion species. They may be microscopic in size but they Is Now are magnificent in their evolutionary diversity and astounding in their sheer numbers. Existing in such diversity and numbers in the oceans, the land masses, and the atmosphere means they must possess some amazing powers that contribute to the very survival of other organisms on planet Earth. So, could understanding these microscopic organisms on Earth be as important to us and all earthly creatures as studying stars and galaxies in space? Let’s uncover a few examples of what a “day in the life of a microorganism” is like. A Day in the Life of a Microorganism The oceans and seas cover 70% of planet Earth and are swarming with microbes—some 3 × 1029—and helping regulate life on Earth. Floating near the surface are photosynthetic groups that are part of the marine food chain on which all fish and ocean mammals depend. In addi- tion, they provide up to 50% of the oxygen gas we breathe and other organisms use to stay alive ( FIGURE 1.1A ). Other diverse marine and freshwater microbes are the engines that drive nutrient and mineral recycling needed to provide the building blocks to sustain all life. One particular microbe, called Pelagibacter ubique, accounts for 20% (2.4 × 1028 cells) of marine microbes—and 50% of the microbes in the surface waters of temperate oceans in the summer. What is its daily routine? Image courtesy of Dr. Fred Murphy/CDC. 3 3RD PAGES © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION 4 CHAPTER 1 Microbiology: Then and Now (A) (D) (B) (C) (E) FIGURE 1.1 Daily Life in the Microbial World. Microbes play many roles. For example, (A) photosynthetic microbes inhabit the upper sunlit layer of almost all oceans and bodies of fresh water where they produce food molecules that sustain the aquatic food web and generate oxygen gas. (Bar = 5 µm.) © D.P. Wilson/FLPA/Photo Researchers, Inc. (B) In the soil, microbes degrade dead plants and animals, form beneficial partnerships with plants, and recycle carbon, nitrogen, and sulfur. (Bar = 5 µm.) © David Scharf/Photo Researchers, Inc. (C) Besides their involvement in the forma- tion of rain drops and snowflakes, microbes in the atmosphere are important for water vapor to condense into clouds that help cool the Earth. © Loskutnikov/Shutterstock, Inc. (D) Large numbers of microbes can be found on and in the body where most play beneficial roles for our health. (Bar= 5 µm.) © Visuals Unlimited/Corbis. (E) A few microbes play disease roles and have affected world health. This 1974 photo of a Bengali boy shows the effects of smallpox, which was responsible for 300–500 million deaths during the 20th century.
Load more

Recommended publications
  • C Semmelweisâ•Žs 19Th-Century Cure for Deadly Childbed Fever Ignored
    Headwaters Volume 29 Article 3 2016 Dr. Ignác Semmelweis’s 19th-Century Cure for Deadly Childbed Fever Ignored in Vienna’s Maternity Wards: His Sympathy for Women Victims and Their Newborns Costs Professional Standing Anna Lisa Ohm College of Saint Benedict/Saint John's University, [email protected] Follow this and additional works at: https://digitalcommons.csbsju.edu/headwaters Part of the History of Science, Technology, and Medicine Commons, and the Women's History Commons Recommended Citation Ohm, Anna Lisa (2016) "Dr. Ignác Semmelweis’s 19th-Century Cure for Deadly Childbed Fever Ignored in Vienna’s Maternity Wards: His Sympathy for Women Victims and Their Newborns Costs Professional Standing," Headwaters: Vol. 29, 23-35. Available at: https://digitalcommons.csbsju.edu/headwaters/vol29/iss1/3 This Article is brought to you for free and open access by DigitalCommons@CSB/SJU. It has been accepted for inclusion in Headwaters by an authorized editor of DigitalCommons@CSB/SJU. For more information, please contact [email protected]. ANNA LISA OHM ____________________________________ Dr. Ignác Semmelweis’s 19th-Century Cure for Deadly Childbed Fever Ignored in Vienna’s Maternity Wards: His Sympathy for Women Victims and Their Newborns Costs Professional Standing For some 19th-century women ready to give birth, even a public street was preferable to a bed in an accredited hospital delivery ward where statistics suggested a massacre of women and newborns throughout Europe and the United States. Puerperal septicemia, commonly called childbed fever, was the culprit, and nobody in the world’s medical or scientific community at the time knew how to control its epidemic proportions.
    [Show full text]
  • Biographical References for Nobel Laureates
    Dr. John Andraos, http://www.careerchem.com/NAMED/Nobel-Biographies.pdf 1 BIOGRAPHICAL AND OBITUARY REFERENCES FOR NOBEL LAUREATES IN SCIENCE © Dr. John Andraos, 2004 - 2021 Department of Chemistry, York University 4700 Keele Street, Toronto, ONTARIO M3J 1P3, CANADA For suggestions, corrections, additional information, and comments please send e-mails to [email protected] http://www.chem.yorku.ca/NAMED/ CHEMISTRY NOBEL CHEMISTS Agre, Peter C. Alder, Kurt Günzl, M.; Günzl, W. Angew. Chem. 1960, 72, 219 Ihde, A.J. in Gillispie, Charles Coulston (ed.) Dictionary of Scientific Biography, Charles Scribner & Sons: New York 1981, Vol. 1, p. 105 Walters, L.R. in James, Laylin K. (ed.), Nobel Laureates in Chemistry 1901 - 1992, American Chemical Society: Washington, DC, 1993, p. 328 Sauer, J. Chem. Ber. 1970, 103, XI Altman, Sidney Lerman, L.S. in James, Laylin K. (ed.), Nobel Laureates in Chemistry 1901 - 1992, American Chemical Society: Washington, DC, 1993, p. 737 Anfinsen, Christian B. Husic, H.D. in James, Laylin K. (ed.), Nobel Laureates in Chemistry 1901 - 1992, American Chemical Society: Washington, DC, 1993, p. 532 Anfinsen, C.B. The Molecular Basis of Evolution, Wiley: New York, 1959 Arrhenius, Svante J.W. Proc. Roy. Soc. London 1928, 119A, ix-xix Farber, Eduard (ed.), Great Chemists, Interscience Publishers: New York, 1961 Riesenfeld, E.H., Chem. Ber. 1930, 63A, 1 Daintith, J.; Mitchell, S.; Tootill, E.; Gjersten, D., Biographical Encyclopedia of Scientists, Institute of Physics Publishing: Bristol, UK, 1994 Fleck, G. in James, Laylin K. (ed.), Nobel Laureates in Chemistry 1901 - 1992, American Chemical Society: Washington, DC, 1993, p. 15 Lorenz, R., Angew.
    [Show full text]
  • Introduction to Microbiology: Then and Now
    © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC (right) Courtesy of Jed Alan Fuhrman, University of Southern University (right) Courtesy of Jed Alan Fuhrman, (left) Courtesy of JPL-Caltech/NASA. California. CHAPTER 1 NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Introduction© Jones & Bartlett Learning, LLC to © Jones & Bartlett Learning, LLC Microbiology:NOT FOR SALE OR DISTRIBUTION ThenNOT FOR and SALE OR DISTRIBUTIONNow © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALECHAPTER OR DISTRIBUTION KEY CONCEPTS NOT FOR SALE OR DISTRIBUTION 1-1 Microbial Communities Support and Affect All Life on Earth 1-2 The Human Body Has Its Own Microbiome 1-3 Microbiology Then: The Pioneers 1-4 The Microbial© WorldJones Is Cat& Bartlettaloged into Learning, Unique Groups LLC © Jones & Bartlett Learning, LLC 1-5 MicrobiologyNOT Now :FOR Challenges SALE Remain OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC Earth’s Microbiomes NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Space and the universe often appear to be an unlimited frontier. The chapter opener image on the left shows one of an estimated 350 billion large galaxies and more than 1024 stars in the known universe. However, there is another 30 invisible frontier here on Earth. This is the microbial universe, which consists of more than 10 microorganisms (or microbes for short). As the chapter opener image on the right shows, microbes might be microscopic in size, but, as we will see, they are magnificent in their evolutionary diversity and astounding in their sheer numbers.
    [Show full text]
  • René Dubos, Tuberculosis, and the “Ecological Facets of Virulence”
    HPLS (2017) 39:15 DOI 10.1007/s40656-017-0142-5 ORIGINAL PAPER René Dubos, tuberculosis, and the “ecological facets of virulence” Mark Honigsbaum1 Received: 15 January 2017 / Accepted: 23 June 2017 / Published online: 4 July 2017 © The Author(s) 2017. This article is an open access publication Abstract Reflecting on his scientific career toward the end of his life, the French- educated medical researcher Rene´ Dubos presented his flowering as an ecological thinker as a story of linear progression—the inevitable product of the intellectual seeds planted in his youth. But how much store should we set by Dubos’s account of his ecological journey? Resisting retrospective biographical readings, this paper seeks to relate the development of Dubos’s ecological ideas to his experimental practices and his career as a laboratory researcher. In particular, I focus on Dubos’s studies of tuberculosis at the Rockefeller Institute in the period 1944–1956—studies which began with an inquiry into the tubercle bacillus and the physiochemical determinants of virulence, but which soon encompassed a wider investigation of the influence of environmental forces and host–parasite interactions on susceptibility and resistance to infection in animal models. At the same time, through a close reading of Dubos’s scientific papers and correspondence, I show how he both drew on and distinguished his ecological ideas from those of other medical researchers such as Theobald Smith, Frank Macfarlane Burnet, and Frank Fenner. However, whereas Burnet and Fenner tended to view ecological interactions at the level of populations, Dubos focused on the interface of hosts and parasites in the physio- logical environments of individuals.
    [Show full text]
  • Microbiology Immunology Cent
    years This booklet was created by Ashley T. Haase, MD, Regents Professor and Head of the Department of Microbiology and Immunology, with invaluable input from current and former faculty, students, and staff. Acknowledgements to Colleen O’Neill, Department Administrator, for editorial and research assistance; the ASM Center for the History of Microbiology and Erik Moore, University Archivist, for historical documents and photos; and Ryan Kueser and the Medical School Office of Communications & Marketing, for design and production assistance. UMN Microbiology & Immunology 2019 Centennial Introduction CELEBRATING A CENTURY OF MICROBIOLOGY & IMMUNOLOGY This brief history captures the last half century from the last history and features foundational ideas and individuals who played prominent roles through their scientific contributions and leadership in microbiology and immunology at the University of Minnesota since the founding of the University in 1851. 1. UMN Microbiology & Immunology 2019 Centennial Microbiology at Minnesota MICROBIOLOGY AT MINNESOTA Microbiology at Minnesota has been From the beginning, faculty have studied distinguished from the beginning by the bacteria, viruses, and fungi relevant to breadth of the microorganisms studied important infectious diseases, from and by the disciplines and sub-disciplines early studies of diphtheria and rabies, represented in the research and teaching of through poliomyelitis, streptococcal and the faculty. The Microbiology Department staphylococcal infection to the present itself, as an integral part of the Medical day, HIV/AIDS and co-morbidities, TB and School since the department’s inception cryptococcal infections, and influenza. in 1918-1919, has been distinguished Beyond medical microbiology, veterinary too by its breadth, serving historically microbiology, microbial physiology, as the organizational center for all industrial microbiology, environmental microbiological teaching and research microbiology and ecology, microbial for the whole University.
    [Show full text]
  • Nobel Prizes in Physiology Or Medicine with an Emphasis on Bacteriology
    J Med Bacteriol. Vol. 8, No. 3, 4 (2019): pp.49-57 jmb.tums.ac.ir Journal of Medical Bacteriology Nobel Prizes in Physiology or Medicine with an Emphasis on Bacteriology 1 1 2 Hamid Hakimi , Ebrahim Rezazadeh Zarandi , Siavash Assar , Omid Rezahosseini 3, Sepideh Assar 4, Roya Sadr-Mohammadi 5, Sahar Assar 6, Shokrollah Assar 7* 1 Department of Microbiology, Medical School, Rafsanjan University of Medical Sciences, Rafsanjan, Iran. 2 Department of Anesthesiology, Medical School, Kerman University of Medical Sciences, Kerman, Iran. 3 Department of Infectious and Tropical Diseases, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran. 4 Department of Pathology, Dental School, Shiraz University of Medical Sciences, Shiraz, Iran. 5 Dental School, Rafsanjan University of Medical Sciences, Rafsanjan, Iran. 6 Dental School, Shiraz University of Medical Sciences, Shiraz, Iran. 7 Department of Microbiology and Immunology of Infectious Diseases Research Center, Research Institute of Basic Medical Sciences, Rafsanjan University of Medical Sciences, Rafsanjan, Iran. ARTICLE INFO ABSTRACT Article type: Background: Knowledge is an ocean without bound or shore, the seeker of knowledge is (like) the Review Article diver in those seas. Even if his life is a thousand years, he will never stop searching. This is the result Article history: of reflection in the book of development. Human beings are free and, to some extent, have the right to Received: 02 Feb 2019 choose, on the other hand, they are spiritually oriented and innovative, and for this reason, the new Revised: 28 Mar 2019 discovery and creativity are felt. This characteristic, which is in the nature of human beings, can be a Accepted: 06 May 2019 motive for the revision of life and its tools and products.
    [Show full text]
  • Theobald Smith
    VITA Theobald Smith Brief life of a pioneering comparative pathologist: 1859–1934 by steven m. niemi hen theobald smith arrived at Harvard in 1895, he first Fabyan professor of comparative pathology in 1896, and was already accomplished in the nascent fields of microbi- served until the Rockefeller Institute lured him away in 1915. ology, immunology, and public health. Eleven years earlier, He wasted no time in applying his meticulous approach to the newly graduated from Albany Medical College at 25, he had begun production of biologics, increasing the potency of diphtheria anti- his career at the new Bureau of Animal Industry in Washington, serum fourfold, while the annual number of free doses distributed D.C., created by Congress to investigate common livestock dis- in Massachusetts rose from 1,724 in 1895-96 to 40,211 in 1901-02, eases such as hog cholera, Texas cattle fever, and swine plague. sparing an estimated 10,700 lives. This endeavor also produced the These and other affl ictions threatened the supply of meat to an in- first description of immune-mediated hypersensitivity—anaphy- creasingly urban population that depended on railroads to deliver laxis, known for years as the “Theobald Smith phenomenon”— vast numbers of cattle and pigs to centralized processing plants. when guinea pigs re-injected with horse serum suddenly died. Though Smith had no prior experience in animal pathology and He tackled other common but deadly diseases as well. He de- little guidance existed on culturing and characterizing microbes, vised a method for measuring the level of fecal contamination of he discovered not only how ticks (and by inference, insects and municipal drinking water (a principal source of typhoid fever and other bugs) could harbor and transmit infectious diseases, but also cholera) that could be adapted easily to determine the relative effi - that injections of heat-killed bacteria could bestow immunity.
    [Show full text]
  • Transactions of the Congress American
    TRANSACTIONS OF THE C O N G R ES S AmericanPhysicians and Surgeons F O UR T E E N T H T R I E N N I A L S E S S I O N HELD AT WA H NGT D (i S O N . I , . M a l s t and nd 19 8 y 2 , 2 PUBLISHED BY THE CONGRESS N NNN NNNNN NNNNN Ente r e d ac c o rding to Ac t o f Co ngre ss i n th e y e ar 1 93 0 R TEI N R MD e r h n b WALTER . E . e c r ta o f t e Co r e s s y S , , S y g o f Copies may be had the Secretary . T HE T UTTLE MO REHO US E TAYLOR CO MP ANY NEW HAVEN ONN , , , C . TAB LE OF C ONTENT S Table o f Contents Titles O f Papers to be read at Congress Officers O f th e Cong ress Executive Co mmittee Committe e O f Arrang e me nts Past Officers o f th e Cong ress By -Laws o f the Cong ress Minute s Of th e Fourteenth Sessiono f th e Cong re ss 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ’ THE PRESIDENT S ADDRES S :— THE DECLINE OF INFECTIOUS DISEASES IN ITS RELATI ON TO O B OB M DERN MEDICINE ; Y D R.
    [Show full text]
  • Balcomk41251.Pdf (558.9Kb)
    Copyright by Karen Suzanne Balcom 2005 The Dissertation Committee for Karen Suzanne Balcom Certifies that this is the approved version of the following dissertation: Discovery and Information Use Patterns of Nobel Laureates in Physiology or Medicine Committee: E. Glynn Harmon, Supervisor Julie Hallmark Billie Grace Herring James D. Legler Brooke E. Sheldon Discovery and Information Use Patterns of Nobel Laureates in Physiology or Medicine by Karen Suzanne Balcom, B.A., M.L.S. Dissertation Presented to the Faculty of the Graduate School of The University of Texas at Austin in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy The University of Texas at Austin August, 2005 Dedication I dedicate this dissertation to my first teachers: my father, George Sheldon Balcom, who passed away before this task was begun, and to my mother, Marian Dyer Balcom, who passed away before it was completed. I also dedicate it to my dissertation committee members: Drs. Billie Grace Herring, Brooke Sheldon, Julie Hallmark and to my supervisor, Dr. Glynn Harmon. They were all teachers, mentors, and friends who lifted me up when I was down. Acknowledgements I would first like to thank my committee: Julie Hallmark, Billie Grace Herring, Jim Legler, M.D., Brooke E. Sheldon, and Glynn Harmon for their encouragement, patience and support during the nine years that this investigation was a work in progress. I could not have had a better committee. They are my enduring friends and I hope I prove worthy of the faith they have always showed in me. I am grateful to Dr.
    [Show full text]
  • Introduction to Plant Diseases
    An Introduction to Plant Diseases David L. Clement, Regional Specialist - Plant Pathology Maryland Institute For Agriculture And Natural Resources Modified by Diane M. Karasevicz, Cornell Cooperative Extension Cornell University, Department of Plant Pathology Learning Objectives 1. Gain a general understanding of disease concepts. 2. Become familiar with the major pathogens that cause disease in plants. 3. Gain an understanding of how pathogens cause disease and their interactions with plants.· 4. Be able to distinguish disease symptoms from other plant injuries. 5. Understand the basic control strategies for plant diseases. Introduction to Plant Diseases The study of plant disease is covered under the science of Phytopathology, which is more commonly called Plant Pathology. Plant pathologists study plant diseases caused by fungi, bacteria. viruses and similar very small microbes (mlos. viroids, etc.), parasitic plants and nematodes. They also study plant disorders caused by abiotic problems. or non-living causes, associated with growing conditions. These include drought and freezing damage. nutrient imbalances, and air pollution damage. A Brief History of Plant Disea~es Plant diseases have had profound effects on mankind through the centuries as evidenced by Biblical references to blasting and mildew of plants. The Greek philosopher Theophrastus (370-286 BC) was the first to describe maladies of trees,. cereals and legumes that we today classify as leaf scorch, rots, scab, and cereal rust. The Romans were also aware of rust diseases of their grain crops. They celebrated lhe holiday of Robigalia that involved sacrifices of reddish colored dogs and catde in an attempt to appease the rust god Robigo. With the invention of the microscope in th~ seventeenth century fungi and bacteria associated with plants were investigated.
    [Show full text]
  • History of Microbiology: Spontaneous Generation Theory
    HISTORY OF MICROBIOLOGY: SPONTANEOUS GENERATION THEORY Microbiology often has been defined as the study of organisms and agents too small to be seen clearly by the unaided eye—that is, the study of microorganisms. Because objects less than about one millimeter in diameter cannot be seen clearly and must be examined with a microscope, microbiology is concerned primarily with organisms and agents this small and smaller. Microbial World Microorganisms are everywhere. Almost every natural surface is colonized by microbes (including our skin). Some microorganisms can live quite happily in boiling hot springs, whereas others form complex microbial communities in frozen sea ice. Most microorganisms are harmless to humans. You swallow millions of microbes every day with no ill effects. In fact, we are dependent on microbes to help us digest our food and to protect our bodies from pathogens. Microbes also keep the biosphere running by carrying out essential functions such as decomposition of dead animals and plants. Microbes are the dominant form of life on planet Earth. More than half the biomass on Earth consists of microorganisms, whereas animals constitute only 15% of the mass of living organisms on Earth. This Microbiology course deals with • How and where they live • Their structure • How they derive food and energy • Functions of soil micro flora • Role in nutrient transformation • Relation with plant • Importance in Industries The microorganisms can be divided into two distinct groups based on the nucleus structure: Prokaryotes – The organism lacking true nucleus (membrane enclosed chromosome and nucleolus) and other organelles like mitochondria, golgi body, entoplasmic reticulum etc. are referred as Prokaryotes.
    [Show full text]
  • Louis Pasteur
    Britannica LaunchPacks | Louis Pasteur Louis Pasteur For Grades 6-8 This Pack contains: 5 ARTICLES 4 IMAGES 1 VIDEO © 2020 Encyclopædia Britannica, Inc. 1 of 47 Britannica LaunchPacks | Louis Pasteur Louis Pasteur (1822–95). The French chemist Louis Pasteur devoted his life to solving practical problems of industry, agriculture, and medicine. His discoveries have saved countless lives and created new wealth for the world. Among his discoveries are the pasteurization process and ways of preventing silkworm diseases, anthrax, chicken cholera, and rabies. Louis Pasteur. Archives Photographiques, Paris Pasteur sought no profits from his discoveries, and he supported his family on his professor’s salary or on a modest government allowance. In the laboratory he was a calm and exact worker; but once sure of his findings, he vigorously defended them. Pasteur was an ardent patriot, zealous in his ambition to make France great through science. Scholar and Scientist Louis Pasteur was born on Dec. 27, 1822, in Dôle, France. His father was a tanner. In 1827 the family moved to nearby Arbois, where Louis went to school. He was a hard-working pupil but not an especially brilliant one. When he was 17 he received a degree of bachelor of letters at the Collège Royal de Besançon. For the next three years he tutored younger students and prepared for the École Normale Supérieure, a noted teacher-training college in Paris. As part of his studies he investigated the crystallographic, chemical, and optical properties of © 2020 Encyclopædia Britannica, Inc. 2 of 47 Britannica LaunchPacks | Louis Pasteur various forms of tartaric acid.
    [Show full text]