Transcript Introduction to Microbiology

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
FIRST DEMONSTRATION OF BACTERIAL
DISEASE: 1876- Robert Koch
 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)
Koch’s postulates
Koch’s Postulates
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.
Exceptions to 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
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.