CHAPTER 1 INTRODUCTION TO MICROBIOLOGY WELCOME TO BIOLOGY

Microbes in Our Lives § Microorganisms are organisms that are too small to be seen with the unaided eye. § “Germ” refers to a rapidly growing cell. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

§ § § WHY STUDY MICROBIOLOGY Public Health Applications Food Applications Industrial Applications Biofuels Applications Biopharmaceutical applications Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Microorganisms § Decompose organic waste § Are producers in the ecosystem by photosynthesis § Produce industrial chemicals such as ethanol and acetone § Produce fermented foods such as vinegar, cheese, and bread Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Microorganisms Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 1.

Microorganisms § Produce products used in manufacturing (e. g. , cellulase) and treatment (e. g. , insulin) § A few are pathogenic, disease-causing Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Knowledge of Microorganisms § Allows humans to § Prevent food spoilage § Prevent disease occurrence § Led to aseptic techniques to prevent contamination in medicine and in microbiology laboratories. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Naming and Classifying Microorganisms § Linnaeus established the system of scientific nomenclature. § Each organism has two names: the genus and specific epithet. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Scientific Names § Are italicized or underlined. The genus is capitalized and the specific epithet is lower case. § Are “Latinized” and used worldwide. § May be descriptive or honor a scientist. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Scientific Names § Staphylococcus aureus § Describes the clustered arrangement of the cells (staphylo-) and the golden color of the colonies (aur-). Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Scientific Names § Escherichia coli § Honors the discoverer, Theodor Escherich, and describes the bacterium’s habitat–the large intestine or colon. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Scientific Names § After the first use, scientific names may be abbreviated with the first letter of the genus and the specific epithet: § Staphylococcus aureus and Escherichia coli are found in the human body. S. aureus is on skin and E. coli in the large intestine. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Bacteria § Prokaryotes § Peptidoglycan cell walls § Binary fission § For energy, use organic chemicals, inorganic chemicals, or photosynthesis Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 1. 1 a

Archaea § Prokaryotic § Lack peptidoglycan § Live in extreme environments § Include § Methanogens § Extreme halophiles § Extreme thermophiles Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 4. 5 b

Fungi § Eukaryotes § Chitin cell walls § Use organic chemicals for energy. § Molds and mushrooms are multicellular consisting of masses of mycelia, which are composed of filaments called hyphae. § Yeasts are unicellular. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 1. 1 b

Protozoa § Eukaryotes § Absorb or ingest organic chemicals § May be motile via

Algae § Eukaryotes § Cellulose cell walls § Use photosynthesis for energy § Produce molecular oxygen and organic compounds Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 1. 1 d

Viruses § Acellular § Consist of DNA or RNA core § Core is surrounded by a protein coat. § Coat may be enclosed in a lipid envelope. § Viruses are replicated only when they are in a living host cell. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 1. 1 e

Multicellular Animal Parasites § Eukaryote § Multicellular animals § Parasitic flatworms and round worms are called helminths. § Microscopic stages in life cycles. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 12. 28 a

Linnaeus’s Classification § Hierarchical system § Binomial Nomenclature Copyright © 2006 Pearson Education, Inc.

Classification of Microorganisms § Three domains § Bacteria § Archaea § Eukarya § Protists

A Brief History of Microbiology § Ancestors of bacteria were the first life on Earth. § The first microbes were observed in 1673. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

The First Observations § In 1665, Robert Hooke reported that living things were composed of little boxes or cells. § In 1858, Rudolf Virchow said cells arise from preexisting cells. § Cell theory: All living things are composed of cells and come from preexisting cells. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Leeuwenhoek § Early Observations Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin

The First Observations § 1673 -1723, Antoni van Leeuwenhoek described live microorganisms that he observed in teeth scrapings, rain water, and peppercorn infusions. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 1. 2 b

The Debate Over Spontaneous Generation § The hypothesis that living organisms arise from nonliving matter is called spontaneous generation. According to spontaneous generation, a “vital force” forms life. § The alternative hypothesis, that the living organisms arise from preexisting life, is called biogenesis. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Evidence Pro and Con § 1668: Francisco Redi filled six jars with decaying meat. Conditions Results Three jars covered with fine net No maggots Three open jars Maggots appeared From where did the maggots come? What was the purpose of the sealed jars? Spontaneous generation or biogenesis? Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Evidence Pro and Con § 1745: John Needham put boiled nutrient broth into covered flasks. Conditions Results Nutrient broth heated, then Microbial growth placed in sealed flask From where did the microbes come? Spontaneous generation or biogenesis? Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Evidence Pro and Con § 1765: Lazzaro Spallanzani boiled nutrient solutions in flasks. Conditions Results Nutrient broth placed in flask, No microbial growth heated, then sealed Spontaneous generation or biogenesis? Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Evidence Pro and Con § 1861: Louis Pasteur demonstrated that microorganisms are present in the air. Conditions Results Nutrient broth placed in flask, Microbial growth heated, not sealed Nutrient broth placed in flask, No microbial growth heated, then sealed Spontaneous generation or biogenesis? Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

The Theory of Biogenesis § Pasteur’s S-shaped flask kept microbes out but let air

The Golden Age of Microbiology § 1857 -1914 § Beginning with Pasteur’s work, discoveries included the relationship between microbes and disease, immunity, and antimicrobial drugs Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Fermentation and Pasteurization § Pasteur showed that microbes are responsible for fermentation. § Fermentation is the conversion of sugar to alcohol to make beer and wine. § Microbial growth is also responsible for spoilage of food. § Bacteria that use alcohol and produce acetic acid spoil wine by turning it to vinegar (acetic acid). Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Fermentation and Pasteurization § Pasteur demonstrated that these spoilage bacteria could be killed by heat that was not hot enough to evaporate the alcohol in wine. § Pasteruization is the application of a high heat for a short time. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 1. 4 (1 of 3)

The Germ Theory of Disease § 1835: Agostino Bassi showed that a silkworm disease was caused by a fungus. § 1865: Pasteur believed that another silkworm disease was caused by a protozoan. § 1840 s: Ignaz Semmelwise advocated hand washing to prevent transmission of puerperal fever from one OB patient to another. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

The Germ Theory of Disease § 1860 s: Joseph Lister used a chemical disinfectant to prevent surgical wound infections after looking at Pasteur’s work showing microbes are in the air, can spoil food, and cause animal diseases. § 1876: Robert Koch proved that a bacterium causes anthrax and provided the experimental steps, Koch’s postulates, to prove that a specific microbe causes a specific disease. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Pasteur § Spontaneous generation vs. biogenesis § Germ Theory § Father of aseptic techniques § Pasteurization § Fermentation research § Vaccination (rabies) Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Koch § Koch’s Postulates § Pure Culture Concept § Tuberculosis Copyright © 2006 Pearson

Magic Bullets § Chemotherapy with chemicals – synthetic drugs and antibiotics § Ehrlich and salversan § Sulfonamides § Fleming and penicillin § Drug resistance issues today Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Vaccination § 1796: Edward Jenner inoculated a person with cowpox virus. The person was then protected from smallpox. § Vaccination is derived from vacca for cow. § The protection is called immunity. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

The Birth of Modern Chemotherapy § Treatment with chemicals is chemotherapy. § Chemotherapeutic agents used to treat infectious disease can be synthetic drugs or antibiotics. § Antibiotics are chemicals produced by bacteria and fungi that inhibit or kill other microbes. § Quinine from tree bark was long used to treat malaria. § 1910: Paul Ehrlich developed a synthetic arsenic drug, salvarsan, to treat syphilis. § 1930 s: Sulfonamides were synthesized. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

The Birth of Modern Chemotherapy § 1928: Alexander Fleming discovered the first antibiotic. § He observed that Penicillium fungus made an antibiotic, penicillin, that killed S. aureus. § 1940 s: Penicillin was tested clinically and mass produced. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 1. 5

Modern Developments in Microbiology § Bacteriology is the study of bacteria. § Mycology is the study of fungi. § Parasitology is the study of protozoa and parasitic worms. § Recent advances in genomics, the study of an organism’s genes, have provided new tools for classifying microorganisms. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Modern Developments in Microbiology § Immunology is the study of immunity. Vaccines and interferons are being investigated to prevent and cure viral diseases. § The use of immunology to identify some bacteria according to serotypes (variants within a species) was proposed by Rebecca Lancefield in 1933. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 1. 4 (3 of 3)

Modern Developments in Microbiology § Virology is the study of viruses. § Recombinant DNA is DNA made from two different sources. In the 1960 s, Paul Berg inserted animal DNA into bacterial DNA and the bacteria produced an animal protein. § Recombinant DNA technology, or genetic engineering, involves microbial genetics and molecular biology. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Modern Developments in Microbiology § Using microbes § George Beadle and Edward Tatum showed that genes encode a cell’s enzymes (1942). § Oswald Avery, Colin Mac. Leod, and Maclyn Mc. Carty showed that DNA was the hereditary material (1944). § Francois Jacob and Jacques Monod discovered the role of m. RNA in protein synthesis (1961). Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Selected Novel Prizes in Physiology or Medicine 1901* 1902 1905 1908 1945 1952 1969 1987 1997 von Behring Ross Koch Metchnikoff Fleming, Chain, Florey Waksman Delbrück, Hershey, Luria Tonegawa Prusiner Diphtheria antitoxin Malaria transmission TB bacterium Phagocytes Penicillin Streptomycin Viral replication Antibody genetics Prions * The first Nobel Prize in Physiology or Medicine. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

A Brief History of Microbiology § Linnaeus § Darwin § Jenner § Salk § Hooke § Watson & Crick § Leeuwenhoek § Jacob and Monod § Lister § Mc. Clintock § Pasteur § Woese § Koch § Venter? Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Microbes and Human Welfare § Microbial ecology § Bacteria recycle carbon, nutrients, sulfur, and phosphorus that can be used by plants and animals. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Bioremediation § Bacteria degrade organic matter in sewage. § Bacteria degrade or detoxify pollutants such as oil and mercury. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings UN 2. 1

Biological Insecticides § Microbes that are pathogenic to insects are alternatives to chemical pesticides in preventing insect damage to agricultural crops and disease transmission. § Bacillus thuringiensis infections are fatal in many insects but harmless to other animals, including humans, and to plants. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Modern Biotechnology and Genetic Engineering § Biotechnology, the use of microbes to produce foods and chemicals, is centuries old. § Genetic engineering is a new technique for biotechnology. Through genetic engineering, bacteria and fungi can produce a variety of proteins including vaccines and enzymes. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Modern Biotechnology and Genetic Engineering (continued) § Missing or defective genes in human cells can be replaced in gene therapy. § Genetically modified bacteria are used to protect crops from insects and from freezing. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Microbes and Human Disease § Bacteria were once classified as plants giving rise to use of the term flora for microbes. § This term has been replaced by microbiota. § Microbes normally present in and on the human body are called normal microbiota. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Normal Microbiota § Normal microbiota prevent growth of pathogens. § Normal microbiota produce growth factors such as folic acid and vitamin K. § Resistance is the ability of the body to ward off disease. § Resistance factors include skin, stomach acid, and antimicrobial chemicals. § Biofilms are extremely important in microbial ecology Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Infectious Diseases § When a pathogen overcomes the host’s resistance, disease results. § Emerging infectious diseases (EID): New diseases and diseases increasing in incidence. Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Infectious Disease Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Normal Microbiota § What is normal? Copyright © 2006 Pearson Education, Inc. , publishing

Salad Bars § Why are these a problem today? Copyright © 2006 Pearson Education,

Emerging Infectious Diseases § West Nile encephalitis § West Nile virus § First diagnosed in the West Nile region of Uganda in 1937 § Appeared in New York City in 1999 Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Emerging Infectious Diseases § § § Avian Influenza A H 5 N 1 Severe acute respiratory syndrome (SARS) West Nile encephalitis (WNE) Bovine spongiform encephalitis (BSE) Creutzfeld-Jacob disease (CJD) 0157: H 7 E. coli Flesh eating bacteria Ebola Marburg Cryptosporidiosis AIDS HIV virus Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Emerging Infectious Diseases § Bovine spongiform encephalopathy § Prion § Also causes Creutzfeldt-Jakob disease (CJD) § New variant CJD in humans is related to cattle fed sheep offal for protein Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Emerging Infectious Diseases § Escherichia coli O 57: H 7 § Toxin-producing strain of E. coli § First seen in 1982 § Leading cause of diarrhea worldwide Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Emerging Infectious Diseases § Invasive group A Streptococcus § Rapidly growing bacteria that cause extensive tissue damage § Increased incidence since 1995 Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Emerging Infectious Diseases § Ebola hemorrhagic fever § Ebola virus § Causes fever, hemorrhaging, and blood clotting § First identified near Ebola River, Congo § Outbreaks every few years Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Emerging Infectious Diseases § Avian influenza A § Influenza A virus (H 5 N 2) § Primarily in waterfowl and poultry § Sustained human-to-human transmission has not occurred yet § Swine Flu – (H 1 N 1) – expected to be a pandemic for the next 3 years. May infect >1 billion people Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Emerging Infectious Diseases § Severe acute respiratory syndrome (SARS) § SARS-associated Coronavirus § Occurred in 2002 -2003 § Person-to-person transmission Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Emerging Infectious Diseases § Acquired immunodeficiency syndrome (AIDS) § Human immunodeficiency virus (HIV) § First identified in 1981 § Worldwide epidemic infecting 44 million people; 14, 000 new infections every day § Sexually transmitted disease affecting males and females § In the United States, HIV/AIDS cases: 30% are female and 75% are African American Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings

Emerging Infectious Diseases § Cryptosporidiosis § Cryptosporidium protozoa § First reported in 1976 § Causes 30% of diarrheal illness in developing countries § In the United States, transmitted via water Copyright © 2006 Pearson Education, Inc. , publishing as Benjamin Cummings