Introduction to Microbiology

Introduction Microbes are ubiquitous (everywhere) Friends & Enemies Of great importance to healthcare

What is Microbiology The study of microbes organisms that must be viewed with a microscope... viruses, bacteria, protozoa, archae, and some algae, helminths and fungi

Relative sizes of microbes

Microbes (cont.) microbes may be classified as cellular or acellular (viruses & prions) most are harmless, but ~3% are pathogens (cause disease)

Impact of infectious diseases caused by pathogenic microbes

Microbes and Humans We are made up of about 1 trillion cells. At any point in time you have about 10 trillion microbial cells growing on or inside you.

Microbes on us... the microbes living on or in us are referred to as our indigenous microflora some are opportunistic pathogens (can potentially cause harm)

Importance of Microbes Bioremediation - "Remediate" means to solve a problem, and "bio-remediate" means to use biological organisms to solve an environmental problem such as contaminated soil or groundwater. Genetic engineering Nutrient cycling Food webs diagram of the links among species in an ecosystem – essentially who eats what. A food chain shows only the organisms that contribute to the diet of the top consumer Biotechnology Antibiotic production Disease

The First Microbes

Earliest known infectious diseases Early human fossils & organs from mummies show evidence of TB, syphilis, schistosomiasis, and tapeworm infection 1900 BC, Greek army decimated by Bubonic Plague 1122 BC China was ravaged by smallpox

Pioneers in Microbiology

Anton von Leeuwonhoek father of: microbiology, bacteriology, protozoology invented a simple microscope to observe microbes

Robert Hooke Contemporary/ collaborator of Leeuwenhoek Developed the compound microscope Wrote “Micrographia” on observations  Coined the term “cell”

Louis Pasteur Developed pasteurization Developed the germ theory Pioneered vaccinations Promoted hospital practices to minimize disease spread

Robert Koch Developed postulates for linking disease with a particular pathogen 1st demonstration of bacterial caused disease

Anthrax; Bacillus anthracis; (Gr., coal)-refers to the "black" blood in killed, diseased animals cattle and sheep graze in infected pastures anthrax spores (resistant form of bacteria) are in soil  enter bloodstream via mucosal abrasions Animals are very ill, weak, swollen, have black, bloody discharges Animal dies and is buried  earthworms pick up spores and carry them to the surface dirt  animals graze in infected pastures, etc. CONTROL: bury animals at a depth of at least 6 feet (no earthworms this deep) FIRST DEMONSTRATION OF BACTERIAL DISEASE: Robert Koch

1.The suspected microorganism is present in every case of the disease and absent from healthy animals. 2. One must isolate and grow the microorganism in pure culture. 3. Injection (infection) of a healthy host with the microorganism in pure cultures must cause disease. 4. One must be able to isolate the microorganism from the new host. Koch’s postulates Koch’s Postulates

1. not all pathogens thrive in lab culture, 2. some are species specific, 3. some are synergistic, 4. some become less pathogenic when grown in vitro Exceptions to Koch’s Postulates

Careers in Microbiology Medical Microbiology involves the study of pathogens and the diseases they cause, as well as how the body fights those diseases Clinical Microbiology deals mainly with the diagnosis of infectious diseases Soil and Plant Microbiology deals in a variety of settings including microbial ecology, soil microbiology, environmental microbiology and plant pathology.

Employment Opportunities Where do Microbiologists work? Microbiology positions include: Federal and State governmental laboratories (Center for Disease Control, Food and Drug Administration, USDA, Dept. of Energy, etc.) Private environmental consulting companies Pharmaceutical industry Food production specialist Food safety and clinical laboratories Healthcare industry State laboratories Beginning salaries range from $40,000.