Microbiology. Chapter 1. of Microbiology. Many Diverse Disciplines: Biotechnology Genetic engineering & recombinant.

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1 PowerPoint to accompany The Cowan/Talaro Chapter 1 Microbiology: Microbiology Main Themes of A Systems Approach Topics Scope Importance to Cover: Characteristics of Microbiology History Human of Use Microbiology of of Microorganisms Microbes of Microorganisms Chapter 1 Taxonomy Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Specialized Microorganisms living things area too small in biology to be that seen studies by the Groups naked bugseye of also called microbesor Microbiology Bacteria, and Helminths organism Viruses, Fungi, covered: Protozoa, Algae, There 2.) Fungus, are six 3.) main Algae, types 4.) of Virus, microorganisms: 5.) Protozoan, 1.) 6.) bacterium, Helminth. Immunology Public Food, Agricultural epidemiology dairy health microbiology & Scope microbiology and aquatic microbiology of Microbiology Biotechnology Genetic engineering & recombinant Many Diverse Disciplines: DNA technology MICROBIAL Microorganisms HABITATS are reside everywhere. & in ROLES: plants, furniture, virtually soil, everywhere! in on dust the particles, surfaces animals, in of water - 1

2 SOIL AIR TONGUE Microbes UBIQUITOUS!!! recycling. >50% of the are earth s involved oxygen. in photosynthesis-account Decomposition nutrient for Several Microorganisms study part (ology ( reasons ology) of our of environment. are: to microorganisms. study microbiology -the -Important to animal, plant and human health. vitamins, production useful important a source amino for of of food. the in food acids. the production recycling or are important of of antibiotics, waste. in the -Are -Provide forms recombinant the stuff insight of DNA genetic into technology, life processes engineering gene in therapy. all life Microbes and enzymes, are used and bioremediate to extract copper contaminated from ore, synthesize water. drugs Fig. 1.2 Microbial habitats -Only The microorganisms disease. about 1-3%of the innocuous remaining actually cause Infectious or have 97-99% may be Diseases benefits. positive Most common infectious causes of death worldwide. Fig. 1.3 Microbes at work 2

3 Cause of death in USA Cellular Procaryotic Eucaryotic Procaryotic no Eucaryotic nucleus (mitochondria, Organization: etc.) nucleus and and organelles organelles Characteristics of Microorganisms There is a difference between the cell structure of a procaryote and eucaryote. Viruses are neither but are considered particles. Microorganisms vary in size -1µm to 200 nm. 0.2 um * Microscopy Spores Spontaneous Aseptic Germ History theory and technique sterilization generation of Microbiology Fig. 1.7 The size of things 3

4 -Leprosy -Egyptian The Aspergillusspores. history was pharaohs described spores. of microbiology before protected in the the their bible. bible. is pyramids old. It with dates to -The -Hippocrates see Hippocrates(~400 Greeks microorganisms anticipated -only microbiology. the effect. They could not -Thucydides associated ethical He person standards signs and for BC) the symptoms practice set forth to of an certain medicine. enduring illnesses. set He of Thucydidesrealized observed were or by protected objects. potential that transmission and people could who safely by survived person care for to the also plague victims. Microorganisms using a primitive were microscope. first observed by Antonie van Leeuwenhoek, Fig. 1.9 Leeuwenhoek s microscope - Robert Hooke built the first compound microscope about 1665 and saw cells in a strip of cork. - Leeuwenhoek- first observed living microorganisms - animalcules - using a simple compound microscope. He sampled everywhere and saw protozoa, yeast, fungi and many forms of bacteria. (300X) Cell Types Fig. 1.9b Some Spores The resistant Sporeswere microbes in dust and air were meant term completely to sterile sterile was high later heat. identified. and eliminating introduced which sterilization forms from objects or materials. all life -Early arise belief from vital that forces some forms present of in life could -Francesco nonliving from manure, or decomposing etc) matter (flies Spontaneous Redi(1600) generation experiment generation. to Skepticism refute spontaneous designed reigned. an 4

5 Fig. i1.2b Maggots developed from flies Microbes originated from dust in the air!! Fig. i1.2c -John Needhamrefuted these experiments: -The because oxygen for which they had they merely considered driven to off be the competition growth. required using French scientific in Academy 1859 experiments. to of clarify Science the situation held a Results were negated because of harmful treatment of air!!! - Louis Pasteur entered the swan-neck flask experiment. Fig. i1.2d - A difficulty with all of these experiments is that boiling does not necessarily kill all microorganisms..lucky moment!!! 5

6 Medical Microbiology Louis spoilage, Pasteur and disproved showed microbes spontaneous caused generation. fermentation & - John Tyndall conducted similar experiments and identify microbes in dust and air with high heat resistance. - A lucky observation with these experiments is that boiling does not necessarily kill all microorganisms!!! Fig Louis Pasteur Aseptic technique -Ignaz Semmelweis and Joseph Lister developed the concept of aseptic technique. - Ignaz Semmelweis was convinced that when physicians moved from one infected individual to a new individual without adequate washing, disease was transmitted. He was ridiculed. Many growth by sins, diseases of bad microbes character, are caused in the or body poverty, by the and etc. not Germ theory of disease - Lister continued the work and used carbolic acid to sterilize dressings. He too was ridiculed, but eventually he was recognized for the Robert significance Koch verified of the his Germ contribution. theory (Koch s postulates). Medical Microbiology Fig Robert Koch 6

7 - Pasteur developed pasteurization (56 o C/30 min) in the absence of oxygen) to preserve wine from spoilage. - Pasteur prepared the first rabies vaccine made of dried spinal cord from a rabbit infected with rabies virus. Remember that none had any idea of the concept of viruses at that time!! - In the late 18th century, Jenner noted that milkmaids seldom contracted smallpox. Using this observation he developed the first vaccine - successful immunization against smallpox. Koch s infectious postulates agents cannot -why?? be applied to all - Robert Koch, a contemporary of Pasteur, made a critical contribution to the field of infectious disease with his formulation of Koch s postulates. A corollary of this hypothesis is that one infectious agent causes one disease. 1) The specific causative agent must be found in every case. 2) The infectious agent must be isolated in pure culture. 3) Inoculation of the pure infectious agent into a susceptible animal must result in the same disease. 4) The infectious agent must be recovered from the Koch s inoculated animal. infectious postulates diseases agents are cannot not -why?? cause be by applied to all microorganisms -Some diseases microorganisms. diseases microorganisms can be can cause not cause by be different cultured Lady Edward Montagu variolation variolationto to treat Louis against cowpox Pasteur Developed smallpox Jenner protected using the related humans virus Vaccination against introduced vaccines rabies the and term cholera. attenuated vaccines He Cinchona Paul Ehrlich coined (quinine) coined the Europe term to treat malaria Alexander -Developed chemotheraphyand bullet(selective treat syphilis compound and toxicity) the 606 concept (Salvarsan ( Salvarsan) of magic ) to Chemotheraphy Rene penicillin produced Dubos discovered from by Fleming identified the the soil mold bacterium identified Penicillium. two antibiotics lysozyme Bacillus and 7

8 A Primary system for organizing, classifying & naming Carl living classification,nomenclature identification. Linnaeusintroduced things. concerns nomenclature, of taxonomy and are Taxonomy categories or taxa taxonomic Binomial Genus species Both Genus Bacillus,always species-subtilis, (scientific) nomenclature Bacillus italicized or underlined lowercase capitalized Nomenclature subtilis(b. subtilis) The recording biochemical, thereby, process of discovering and scheme. placing the genetic) traits them (physical, of in organisms, a taxonomic Identification Domain Phylum Class Order Familyor Division Levels of Classification Genus species Fig. 1.13a Fig. 1.13b 8

9 Haeckel (1870 s) is credited with the 3 and 4 kingdom system of classification Robert Whitaker (1969) - developed after the five-kingdom system of classification Developed Three -Eubacteria -Archaea odd after the five-kingdom system extreme Eubacteria-true domains: environments, bacteria, that peptidoglycan live in Domains -Eukarya-have etc a nucleus, high & organelles salt, heat, The system standard molecular techniques to five-kingdom became system. develop until biology the were Domain the used Traditional The Whittaker of the was developed by Dr. Woese. The basis of classification Domain system is the rrna sequence information Fig Woese system Monerans Fungi Protists Plants Animals Subdivisions or Kingdoms Archae and Eubacteria Classification Living schemes allow for a Changes universal millions things of tree favoring years change of life phylogenetic gradually over tree. Evolution & less beneficial changes survival are lost. retained 9