MICRO-s10_02 - BIOL 240: General Microbiology General...

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Unformatted text preview: BIOL 240: General Microbiology General Spring 2010 Rm. 22-116 T, Jan. 26, 2010 Dr. Nathan Staples (Ph.D., UCSB 2002) http://www.smccd.edu/accounts/staplesn/biol240/ 1. Pre-Lab Writeups: Be sure to prepare before each Lab W riteups Be Monday’s labs (for BOTH Mon. & Wed.)!! Monday – (What? Why? How? are we doing in the lab??) 2. Pre-llecture slides and study guides available on ecture course website by the night before. • (Print WISELY!! If you choose to do so..) 3. Bi-weekly lab quizzes – practice quiz by this weekly practice Th./Fri.. (Not active yet!!!) Th./Fri.. – http://smccd.mrooms.net/ -- llogin with G# and Password ogin ( = birth date, MMDDYY, if new) birth REVIEW 1. Name and describe the 7 major “groups” tthat include hat Name microorganisms………. microorganisms TODAY’s Objectives: Students should be able to….. 1. Diagram and describe how Louis Pasteur proved how life truly arises. Diagram Louis 2. Describe the work and significance of the discoveries of van Describe Leeuwenhoek, Pasteur, Jenner, Koch and Fleming….. and 3. Diagram & describe Robert Koch’s postulates, and explain their Diagram Robert and significance to modern medicine and infectious disease……. significance 4. Describe the threat of 4 emerging infectious diseases , and the type of Describe emerging and organism that causes each. organism These questions are your HOMEWORK between classes!!!!!! 1 Classification of Classification Microorganisms Microorganisms • Three Domains: (6 Kingdoms) 1. Bacteria 2. Archaea 3. Eukarya a. b. c. d. Protists Fungi Plants Animals Classification of Microbes: A. Bacteria (Eubacteria) • Prokaryotes • Peptidoglycan cell walls • Divide by Binary fission • For energy: – use organic chemicals, use inorganic chemicals, or photosynthesis photosynthesis Haemophilus influenzae Figure 1.1a 2 B. Archaea B. Archaea 1. Prokaryotic 2. Lack peptidoglycan Lack peptidoglycan 3. Live in extreme Live environments environments • Include: – Methanogens – “Extremophiles”: • Extreme halophiles Extreme halophiles • Extreme thermophiles Extreme thermophiles Figure 4.5b C. Fungi • Eukaryotes • Chitin cell walls • Use organic chemicals Use for energy for • Molds and mushrooms and mushrooms are multicellular are multicellular – consisting of masses of consisting mycelia, mycelia – which are composed of which filaments called hyphae hyphae Figure 1.1b • Yeasts are unicellular 3 D. Protozoa (Protista) • Eukaryotes • Absorb or ingest Absorb organic chemicals organic • May be motile via May pseudopods, cilia, or pseudopods cilia, flagella flagella Amoeba Figure 1.1c E. Algae (Protista) • Eukaryotes • Cellulose cell walls • Use photosynthesis Use for energy for • Produce molecular Produce oxygen and organic compounds compounds Volvox Figure 1.1d 4 F. Viruses (acellular!) • Acellular • Consist of DNA or RNA core. Consist RNA • Core is surrounded by a Core protein coat. protein • Coat may be enclosed in a Coat lipid envelope. lipid • Obligate Parasites Obligate (Intracellular) = (Intracellular) replicate only when they are inside of a living host cell. inside HIV on WBC Figure 1.1e G. Multicellular Animal G. Multicellular Animal Parasites Parasites • Eukaryote • Multicellular animals • Parasitic flatworms Parasitic and round worms are called Helminths. Helminths • Microscopic stages in Microscopic life cycles. life Figure 12.28 5 1.2) A Brief History of 1.2) Microbiology Microbiology • Ancestors of bacteria were the first life on Earth. • The first microbes were observed in 1673. The 1673 – Van Leeuwenhoek A. The First Observations • In 1665, Robert Hooke reported that living In 1665 Robert reported things were composed of “little boxes” or or “cells”. – Schleiden (botanist), Schwann (physiologist) (botanist), Schwann • In 1858, Rudolf Virchow said cells only In 1858 Rudolf said arise from preexisting cells. arise • Cell Theory: All living things are composed All of cells and come from preexisting cells of 6 The First Observations • 1673-1723 (studies), (studies), Antoni van Leeuwenhoek Antoni – described live microorganisms described (“animalcules”) – observed in teeth scrapings, rain observed water, and peppercorn infusions water, Figure 1.2 B. The Debate Over B. Spontaneous Generation Spontaneous • Spontaneous Generation: the hypothesis the that living organisms arise from nonliving matter is called. – a “Vital Force” Forms life. • Biogenesis: Alternative hypothesis, that the Alternative living organisms arise from preexisting life. living 7 Evidence Pro and Con - 1 Evidence 1) 1668: Francisco Redi Redi filled six jars with filled decaying meat. decaying Conditions Results 3 jars covered with fine net No maggots 3 open jars Maggots appeared • From where did the maggots come? • What was the purpose of the sealed jars? • Spontaneous generation or biogenesis? Evidence Pro and Con - 2 Evidence 2) 1745: John Needham put boiled nutrient John put broth into covered flasks. broth Conditions Results Nutrient broth heated, then Microbial growth Nutrient then placed in sealed flask • From where did the microbes come? • Spontaneous generation or biogenesis? 8 Evidence Pro and Con - 3 Evidence 3) 1765: Lazzaro Spallanzani boiled nutrient Lazzaro boiled solutions in flasks. solutions Conditions Results Nutrient broth placed in No microbial growth Nutrient flask, heated, then sealed flask, • Spontaneous generation or biogenesis? Evidence Pro and Con - 4 Evidence 4) 1861: Louis Pasteur demonstrated that Louis demonstrated microorganisms are present in the air. microorganisms • The air itself did not create the microbes/life. Results Conditions Nutrient broth placed in Microbial growth Nutrient flask, heated, not sealed flask, Nutrient broth placed in No microbial growth Nutrient flask, heated, then sealed flask, • Spontaneous generation or biogenesis? 9 C. The Theory of Biogenesis • (4b.) Pasteur’s S-shaped (“goose-necked”) flask kept microbes out but let air in. flask Figure 1.3 1.3) The Golden Age 1.3) of Microbiology of • 1857-1914 • Beginning with Pasteur’s work, discoveries included: work, – Food spoilage – souring wine souring and beer and • Yeast fermentation = causative – the relationship between the microbes & disease, – immunity, and and – antimicrobial drugs 10 A. Fermentation & A. Pasteurization Pasteurization • Pasteur showed that microbes are Pasteur responsible for fermentation. fermentation – Fermentation is the conversation of sugar to Fermentation alcohol to make beer and wine. alcohol • Microbial growth is also responsible for Microbial spoilage of food. spoilage – Bacteria that use alcohol and produce acetic acid Bacteria spoil wine by turning it to vinegar (acetic acid). vinegar Fermentation & Pasteurization 1. Pasteur demonstrated: – spoilage bacteria could be spoilage killed by heat • a heat not hot enough to heat evaporate the alcohol in wine. – This application of a high This heat for a short time is called Pasteurization. Pasteurization Figure 1.4 11 B. The Germ Theory of Disease 2. 1835: Agostino Bassi showed a silkworm Agostino showed disease was caused by a fungus. disease 3. 1865: Pasteur believed that another silkworm Pasteur believed disease was caused by a protozoan. disease 4. 1840s: Ignaz Semmelweis Ignaz advocated hand-washing washing to prevent transmission of puerperal fever from one OB patient to another. OB The Germ Theory of Disease 5. 1860s: Joseph Lister used a chemical disinfectant Joseph used to prevent surgical wound infections – after looking at Pasteur’s work showing work microbes are in the air, can spoil food, and cause animal diseases. and 6. 1876: Robert Koch provided proof Robert provided that a bacterium causes anthrax and provided the experimental steps, • Koch’s postulates: used to prove that a used specific microbe causes a specific disease. specific 1. Find microbe present in every case of the disease; Find 2. Isolate pure organism from sick host animals; 2. Isolate 3. Inoculate organism into healthy host get disease; 3. Inoculate get 4. Reisolate pure organism from newly/expt’l sick animals. 4. 12 Koch Koch C. Vaccination C. 7. 1796: Edward Jenner iinoculated a noculated Edward person with cowpox virus. The person was then protected from smallpox. smallpox – Called vaccination from vacca for cow Called vaccination from vacca – The protection is called immunity http://www.nlm.nih.gov/exhibition/smallpox/sp_vaccination.html Jenner D. The Birth of D. Modern Chemotherapy Modern • Treatment with chemicals is chemotherapy. Treatment chemotherapy – Chemotherapeutic agents used to treat infectious Chemotherapeutic disease can be synthetic drugs or antibiotics. disease • Antibiotics are chemicals produced by bacteria are and fungi that inhibit or kill other microbes. and – Quinine from tree bark was long used to treat malaria. 8. 1910: Paul Ehrlich developed a synthetic arsenic Paul developed drug, salvarsan, to treat syphilis. salvarsan to s yphilis • 1930s: Sulfonamides were synthesized. Sulfonamides 13 Birth of Modern Chemotherapy 9. 1928: Alexander Fleming Alexander discovered the first discovered antibiotic. antibiotic. • He observed that He Penicillium fungus made Penicillium fungus an antibiotic, penicillin, – killed S. aureus. killed aureus • 1940s: Penicillin was tested Penicillin clinically and mass produced. produced. Figure 1.5 1.4) Modern Developments in 1.4) Microbiology Microbiology • Bacteriology is the study of bacteria. • Mycology is the study of fungi. • Parasitology iis the study of protozoa and s parasitic worms. parasitic • Recent advances in genomics, the study of Recent genomics the an organism’s genes, have provided new an genes, tools for classifying microorganisms. tools 14 Modern Developments: Immunology & Virology • Immunology iis the study of s acquired resistance to disease. acquired to – Vaccines and interferons are being Vaccines investigated to prevent and cure viral diseases. diseases. • 1933: Rebecca Lancefield 1933: Rebecca proposed the use of immunology to proposed identify some bacteria according to serotypes – (variants within a species = “strains” or (variants or “subspecies”). Figure 1.4 • Virology is the study of viruses. Modern Developments: Modern Recombinant DNA Technology Recombinant • Microbial genetics: The study of how microbes The inherit traits inherit • Molecular biology: The study of how DNA directs The protein synthesis protein • Genomics: The study of an organism’s genes; has genes; provided new tools for classifying microorganisms provided • Recombinant DNA: DNA made from two DNA different sources. – 1960s, Paul Berg inserted animal DNA (SV40) into bacterial 1960s, DNA and the bacteria produced an animal protein. DNA – Recombinant DNA Technology / Genetic Engineering involves microbiial al genetics and molecular biology. Made Genomics possible!! genetics 15 Modern Developments: Big Discoveries Using microbes (Many Nobel prizes!): – George Beadle and Edward Tatum showed George Beadle and Tatum showed that genes encode a cell’s enzymes (1942) genes – Oswald Avery, Colin MacLeod, and Maclyn Oswald Avery Colin MacLeod and Maclyn McCarty showed that DNA was the showed hereditary material (1944). hereditary – Francois Jacob and Jacques Monod Francois Jacob and Monod discovered the role of mRNA in protein discovered synthesis (1961). synthesis • & One gene – one polypeptide (protein) theory One 1.5) Microbes and 1.5) Human Welfare Human Microbial Ecology – Bacteria recycle carbon, nitrogen, Bacteria nutrients, sulfur, and phosphorus that can be used by plants and animals. be 16 A. Bioremediation • Bacteria degrade organic Bacteria matter in sewage. matter • Bacteria degrade or Bacteria detoxify pollutants such as oil and mercury as B. Biological B. Insecticides Insecticides • Microbes that are pathogenic to insects Microbes – alternatives to chemical pesticides alternatives – prevent insect damage to agricultural prevent crops and disease transmission crops Bt TX- • Bacillus thuringiensis iinfections Bacillus thuringiensis nfections are fatal in many insects but harmless to other animals including humans and to plants. including Bt TX+ 17 C. Modern Biotechnology and C. Genetic Engineering Genetic • Biotechnology, the use of microbes to the produce foods and chemicals, is centuries old. produce • Genetic Engineering iis a new technique for s biotechnology. – bacteria and fungi can produce a variety of proteins bacteria including vaccines and enzymes. including – Missing or defective genes in human cells can be Missing replaced in gene therapy. gene D. Microbes &Human Disease • Bacteria were once classified as plants which Bacteria gave rise to use of the term flora for flora for microbes. microbes. • This term has been replaced by Microbiota. This Microbiota – Microbes normally present in and on the human Microbes body are called normal microbiota. microbiota 18 Normal & Pathogenic Microbiota Pathogenic 1. Normal microbiota prevent growth of Normal microbiota prevent pathogens. pathogens. • Normal microbiota produce growth factors such as folic Normal microbiota produce acid and vitamin K. acid 2. Resistance iis the ability of the body to ward off s disease. • Resistance factors include skin, stomach acid, and Resistance antimicrobial chemicals. antimicrobial 3. Pathogenesis: W hen an infectious microbe When overcomes the host’s resistance, disease results. overcomes – Emerging Infectious Diseases (EID): New diseases New and diseases increasing in incidence……. and E. Emerging Infectious Diseases 1. Bovine Spongiform Bovine Encephalopathy Encephalopathy – – – Prion. Also causes Creutzfeldt-Jakob Jakob disease (CJD). disease New-variant CJD iin humans variant CJD n related to cattle fed sheep offal (entrails) for protein. (entrails) 2. Escherichia coli O157:H7 – – – Toxin-producing strain of E. coli. producing E. Fist seen in 1982. Leading cause of diarrhea worldwide. 19 Emerging Infectious Diseases 3. Acquired ImmunoDeficiency Syndrome (AIDS) Acquired ImmunoDeficiency – Human immunodeficiency virus (HIV) – First identified in 1981. – Worldwide epidemic infecting 40 million people; Worldwide • 14,000 new infections every day. – Sexually transmitted disease affecting Sexually males and females. males 4. Anthrax – – – – Bacillus anthracis Bacillus anthracis In 1877, Koch proved B. anthracis causes anthrax. In anthracis Veterinarians and agricultural workers are at risk of cutaneous anthrax. Veterinarians cutaneous IIn 2001, dissemination of B. anthracis via mail infected 22 people. n anthracis Chapter 2 Chemical Principles 20 ...
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