Microbial World and You : Microbial World and You Chapter 1
What is Microbiology? : What is Microbiology? Micro - too small to be seen with the naked eye
Bio - life
ology - study of
Organisms included in the study of Microbiology : Organisms included in the study of Microbiology 1. Bacteria
2. Protozoans
3. Algae
4. Parasites
5. Yeasts and Molds
Fungi
6. Viruses Bacteriology
Protozoology
Phycology
Parasitology
Mycology
Virology Microorganisms - Microbes - Germs
5 Kingdoms of Living Organisms : 5 Kingdoms of Living Organisms 1. Animalia
2. Plantae
3. Fungi
4. Protista
5. Monera - Bacteria and Cyanobacteria
Eukaryotic vs. Prokaryotic
5 Characteristics of Life : 5 Characteristics of Life 1. Cells
2. Maintain structure by taking up chemicals and energy from the environment
3. Respond to stimuli in the external environment
4. Reproduce and pass on their organization to their offspring
5. Evolve and adapt to the environment
Taxonomic Classification : Taxonomic Classification Kingdom
Phylum
Class
Order
Family
Genus
species Man
Animalia
Chordata
Mammalia
Primate
Hominidae
Homo
sapien
Taxonomic Classification : Taxonomic Classification Kingdom
Phylum
Class
Order
Family
Genus
species Cat
Animalia
Chordate
Mammalia
Carnivora
Felidae
Felis
domestica
Binomial System of Taxonomic Classification : Binomial System of Taxonomic Classification Use only the Genus and species
Homo sapien
Felis domestica
Escherichia coli
Genus and species are either underlined or italicized
Genus is always capitilized
species is never capitilized
Classification System : Classification System 3 Domains 1978 Carl Woese
1. Bacteria
Unicellular prokaryotes with cell wall containing peptidoglycan
2. Archaea
Unicellular prokaryotes with no peptodoglycan in cell wall
3. Eukarya
Protista
Fungi
Plantae
Animalia
Bacteria - what comes to mind? : Bacteria - what comes to mind? Diseases
Infections
Epidemics
Food Spoilage
Only 1% of all known bacteria cause human diseases
About 4% of all known bacteria cause plant diseases
95% of known bacteria are non-pathogens
Microbes Benefit Humans : Microbes Benefit Humans 1.Bacteria are primary decomposers - recycle nutrients back into the environment (sewage treatment plants)
2. Microbes produce various food products
cheese, pickles, sauerkraut, green olives
yogurt, soy sauce, vinegar, bread
Beer, Wine, Alcohol
3. Microbes are used to produce Antibiotics : 3. Microbes are used to produce Antibiotics Penicillin
Mold
Penicillium notatum
1928 Alexander Fleming
4. Bacteria synthesize chemicals that our body needs, but cannot synthesize : 4. Bacteria synthesize chemicals that our body needs, but cannot synthesize Example: E. coli
B vitamins - for metabolism
Vitamin K - blood clotting
Escherichia coli
Dr. Escherich
Colon (intestine)
5. Biochemistry and Metabolism : 5. Biochemistry and Metabolism Very simple structure
rapid rate of reproduction
provides “instant” data
6. Microbial Antagonism : 6. Microbial Antagonism Our normal microbial flora prevents potential pathogens from gaining access to our body
7. Insect Pest Control : 7. Insect Pest Control Using bacteria to control the growth of insects
Bacillus thuringiensis
caterpillars
bollworms
corn borers
8. Bioremediation : 8. Bioremediation Using microbes to clean up pollutants and toxic wastes
Exxon Valdez - 1989
2 Genera
Pseudomonas sp.
Bacillus sp.
9. Recombinant DNA Technology Gene Therapy Genetic Engineering : 9. Recombinant DNA Technology Gene Therapy Genetic Engineering Bacteria can be manipulated to produce enzymes and proteins they normally would not produce
Insulin
Human Growth Hormone
Interferon
10. Microbes form the basis of the food chain : 10. Microbes form the basis of the food chain Marine and fresh water microorganisms
Microbes do benefit us, but they are also capable of causing many diseases : Microbes do benefit us, but they are also capable of causing many diseases Pneumonia Whooping Cough
Botulism Typhoid Fever Measles
Cholera Scarlet Fever Mumps
Syphilis Gonorrhea Herpes 1
Chlamydia Tuberculosis Herpes 2
Meningitis Tetanus RMSV
Strep Throat Lyme Disease AIDS
Black Plague Diarrhea Gangrene
History of the Study of Microorganisms : History of the Study of Microorganisms 1665 Robert Hooke
“little boxes” - “cells”
Cell Theory - all living things are made up of cells
Slide 22 : Anton van Leeuwenhoek 1674
- 1st person to actually see living microorganisms “wee animalcules”
Spontaneous Generation : Spontaneous Generation Theory that life just “spontaneously” developed from non-living matter
Example:
toads, snakes and mice - moist soil
flies and maggots - manure and decaying flesh
Experiments to disprove Spontaneous Generation : Experiments to disprove Spontaneous Generation Francesco Redi 1668
Rudolph Virchow 1858
Theory of Biogenesis
Cells can only arise from preexisting cells
Louis Pasteur 1861
Slide 25 : Pasteur designed special “swan-necked flasks” with a boiled meat infusion Shape of flask allowed air in (vital force) but trapped dust particles which may contain microbes
Germ Theory of Disease : Germ Theory of Disease Hard for people to believe that diseases were caused by tiny invisible “wee animalcules”
Diseases, they thought, were caused by:
demons
witchcraft
bad luck
the wrath of God
curses
evil spirits
Robert Koch - 1st to prove that bacteria actually caused diseases : Robert Koch - 1st to prove that bacteria actually caused diseases 1876
Microbial Etiology of Infectious Disease
etiology - the cause of a disease
Established “scientific rules” to show a cause and effect relationship between a microbe and a disease
Koch’s Postulates
Koch’s Postulates : Koch’s Postulates 1. The same organisms must be found in all cases of a given disease.
2. The organism must be isolated and grown in pure culture.
3. The isolated organism must reproduce the same disease when inoculated into a healthy susceptible animal.
4. The original organism must again be isolated from the experimentally infected animal.
Slide 29 : Exceptions to Koch’s Postulates
1. Some organisms have never been grown in pure culture on artificial media Treponema pallidum - Syphilis
Slide 30 : Mycobacterium leprae Leprosy Never been grown in pure culture on artificial media Abdominal cavity of the Seven Banded Armadillo Exceptions to Koch’s Postulates
Exceptions to Koch’s Postulates : Exceptions to Koch’s Postulates In exclusively human diseases, it is not morally acceptable to inoculate a deadly pathogen into a “human guinea pig”
HIV
Koch established the Microbial Etiology of 3 important diseases of his day : Koch established the Microbial Etiology of 3 important diseases of his day 1. Cholera (fecal-oral disease)
Vibrio cholerae
2. Tuberculosis (pulmonary infection)
Mycobacterium tuberculosis
3. Anthrax (sheep and cattle)
Bacillus anthracis
Anthrax : Anthrax Bacillus anthracis
Gram (+), non-motile, aerobic, spore forming rod
Streptobacilli with central spores
Livestock
Sheep, cattle, goats
Humans
Handle hides, wool, goat hair, handicrafts from the Middle East made from animal products
3 Forms of Human Anthrax : 3 Forms of Human Anthrax 1. Cutaneous Anthrax
Enters thru cut or abrasion
Results in painless ulcer (1-3 cm) with black (necrotic) center
About 20% mortality rate in untreated cases
Slide 35 : 2. Gastrointestinal Anthrax
Contaminated meat
Abdominal pain, fever, vomiting blood, severe diarrhea
25% to 60% mortality rate
Slide 36 : 3. Inhalation Anthrax
Initial symptoms resemble common cold
Progress to severe breathing problems and shock
Usually results in death 1-2 days after onset of acute symptoms
Mortality rate 99% in untreated cases
Treatment usually not effective after symptoms are present
Anthrax as a Biological Weapon : Anthrax as a Biological Weapon Deadly if not treated early
Spores can be produced in large quantities using basic knowledge of biology
Spores may remain viable for years (60 at least)
Spores can be spread
Missiles, rockets, bombs, mail, crop dusters ?
No cloud or color
No smell
No taste
Antibiotics – only effective if administered early (within 24 –48 hours)
Koch - 1st to use Agar to solidify culture media : Koch - 1st to use Agar to solidify culture media
Golden Age of Microbiology 1857 - 1914 : Golden Age of Microbiology 1857 - 1914 Pasteur
Pasteurization
Fermentation
Joseph Lister
Phenol to treat surgical wounds – 1st attempt to control infections caused by microoganisms
Robert Koch
Koch’s Postulates
Edward Jenner
vaccination
Paul Erlich
1st synthetic drug used to treat infections
Salvarsan - arsenic based chemical to treat Syphilis
“salvation” from Syphilis
Naming of Bacteria : Naming of Bacteria Genus and species - Binomial System of Taxonomic Classification
Information usually given:
1. Describes an organism
2. Identifies a habitat
3. Honors a scientist or researcher
Bacterial Morphology : Bacterial Morphology Bacilli
Cocci
Spiral
Arrangements : Arrangements Staphylo
Strepto
Diplo
Sarcinae
Tetrad
Vibrio comma shaped
bacter bacilli
bacterium bacilli
Slide 43 : Staphylococcus aureus
Staphylococcus epidermidis
Streptococcus pneumoniae
Vibrio cholerae
Rhodospirillium rubrum
Bacillus subtilis
Micrococcus luteus Escherichia coli
Bacillus anthrasis
Salmonella enteridis
Streptococcus pyogenes
Steptococcus lactis
Streptococcus faecalis
Erlichia canis
Campylobacter jujuni
Helicobacter pylori
Enterobacter aerogenes
Slide 44 :