Transcript General Microbiology 130 Fall 2007

General Microbiology
130 Fall 2007
Roberta BrashearKaulfers
Class cards
Syllabus distribution
Website information:
http://hawaii.hawaii.edu/brashear
Chapter 1 Scope & History of
Microbiology
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Q 1 How would you describe a microbiologist?
Let the adventure begin!
Definitions:
 Microbes- germs that cause disease
 Biology- study of life
 Microorganisms- bacteria, fungi, protozoa and
some algae, closely related to humans
in us, on us, and everywhere around us
Why Study Microbiology?
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1) Microorganisms are part of human
environment, and important to human health
a) essential to life in every environment
b) Maintain balance of nature and essential
links in food chains
2) Produce new foods
3) Ability to synthesize antibiotics
Why Study Microbiology?
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4) Major tools of genetic engineering
5) Certain microbes cause disease
6) Study provides insight into life processes
in all life forms
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EcologistsBiochemistsGeneticists-
Microorganisms are useful in
Research for 3 reasons
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1) Simple structures
2) Large numbers available, less cost,
more numbers provide more reliable
results
3) Reproduce quickly (some 20 minutes), can
be used for gene transfer
Scientists have achieved great success in
understanding life processes, and disease
control by studying microbes
Importance of bacteria to our planet
is now being revealed
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Bacteria have been found in:
1) Deep/hot depths (1.6 km in France –
5.2 km Sweden)
2) Surface biosphere
3) Caves4) Deep sea smokers- ocean floor vents
5) Cold seeps- off Continental shelf of US
6) Boiling mud pots- Japan, Yellowstone
Scope of Microbiology
2 dimensions of Scope
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Microbiology – study of microbes
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1) Variety of kinds of microbes
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2) Kinds of work microbiologists do
Major Groups of Microbes
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1) Bacteria- prokaryotic, single cell, most
studied
2) Algae-eukaryotic, single cell to large
size, photosynthesize own food
3) Fungi- eukaryotic, single celled-yeast and
molds
4) Virus- acellular, nucleic acid and protein
need a host for replication
Major Groups of Microbes
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5) Protozoa-eukaryotic, many mobile
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6) Helminth worms- disease causing parasites
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7) Arthropod – insect vectors
Classification systems
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Binomial nomenclatureeverything has 2 names: Genus – species
Virus are less precise- named for group they belong
to or disease type
Microbiologists study many things and work in many
fields:
life cycles, metabolism, make antibiotics and
vaccines, control crop and insect pests, work in labs
and Universities, create GMO’s, virology, industry
and research
Historical Roots of Microbiology
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1) Bible- Moses
2) Greeks- 400BC Hippocrates
3) Romans- 100BC Varro4) Mediterranean-542 AD Black Deathbubonic plague
5) Europe-1347- 1700 AD – plague spreads
from central Asis through
caravans
*Jewish population less impacted
Historical Roots of Microbiology
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6) Robert Hooke- 1665 compound
microscope, saw cork cells
7) Anton van Leeuwenhoek-1650’s lens
maker, studied “animalcules”
8) Carolus Linnaeus- classification system
of binomial nomenclature
9) Schleiden/Schwann- Cell theory
Germ Theory of Disease
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Microorganisms (germs) can invade other
organisms and cause disease
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Spontaneous generation experiments
Germ Theory of Disease
Early Studies
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Redi- experiments against Spontaneous
generation
Spallanzani- used broth infusions
Pasteur- pasteurization process-heat wine to
56C/without O2 and kills microbes
Robert Koch- physicain who studied anthrax
bacteria, gre pure cultures on agar
Koch’s Postulates: Germ theory of disease
Koch’s Postulates: Germ Theory of
Disease
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1) specific causative agent must be found in
every case of the disease
2) disease organism must be isolated in pure
culture
3) inoculation of sample into a healthy organism
must produce the same disease
4) disease organism must be recovered from
inoculated animal
Koch identified organisms for TB, Cholera, and won
Nobel prize in 1905
Work toward controlling Infections
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1800’s physicians:
SemmelweissLister- father of antiseptic surgery
Emergence of Special Fields of
Microbiology
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Immunology- host response reactions
1100’s Chinese –people who had smallpox and
survived will not get it again
1717- Lady Ashley Montagu- variolation=
took thread with smallpox blister exposure and
place into incision in arm
1800’s Jenner- milkmaids who got cowpox,
did not get smallpox
Immunology
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Jenner created vaccinia-vaccine for small
pox
Pasteur created vaccine for rabies and
cholera
Metchnikoff – 1880 studied phagocytosis
“cell eating” sea star cells.
He received the Nobel prize 1908
Virology
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Virus particles are very small
Chamberland-1884 used a bacterial filter and
particles that went through were still infectious
Beijerinck-infectious particles were called
virus or poisons
Stanley- 1935- TMV tobacco mosiac virus
Hershey/ Chase-1952 genetic material is DNA
Many viruses were discovered in the 1950’s
Chemotherapy
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Greek physicians- extracts from medicinal
plants-digitalis, curare, morphine-herbals
16th cent-metallic chemicals
17th cent- cinchona bark= malaria
19th cent- extracted morphine from opium
poppy
Ehrlich- certain chemicals kill microbes but
not animal cells=he tested 100’s of chemicals
Chemotherapy
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Fleming- 1922 lysozymes
1917- antibiotics from bacteria
1928 to WWII- penicillin became safe
1935- sulfa drugs used for streptococci, TB
1941- Actinomycin antibiotic,
1943- Streptomycin for TB
Some antibiotics from soil, others from the
sea, many others may be in the rainforest
Genetics and Molecular Biology
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1900’s rediscovered Mendel’s work
1928- Griffith discovered live bacteria acquire traits
from dead ones
1940’s- Avery, Mac Leod, McCarty-DNA
1953- Watson and Crick-structure of DNA
1950’s Beadle and Tatum- genetic controls
in Neurospora – yeast
Mc Clintock- jumping genes in corn
Genes shuffle and splice together to create antibodies
Tomorrow’s History
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Microbiology is ongoing
1874-1917- Golden Age of Microbiology
1900 until now, many Nobel Prizes in
physiology and medicine
Microbiology is in the forefront now with
AIDS research and
Genetic engineering-designer microbes
1990 -1st gene therapy patient
Bioethics and the Future
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1920-1930’s Bacteriophage-virus that attack
and kill certain bacteria (still used in Russia
today)
Phages that attack Listeria –foodborne
pathogen created a solution to agricultural
food problems
Bioterrorism-phage to protect against Anthrax
Genomics
Human Genome Project
Goal to Identify human genes
started in 1990 and completed in 2000
3 billion base pairs sequenced = 30,000 genes
75% of the code is “junk” DNA
Similarities between bacteria and human = 43
Similariteies between mouse and human= 300
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