scope and history of microbiology - kcesmjcollege.in · microbiology is the science that studies...
TRANSCRIPT
What is
Mic
robio
logy?
Microbiology is the Science that studies
Microorganisms.
Microorganisms, roughly, are those living things
that are too small to be seen with the naked eye.
Microorganisms cannot be distinguished
Phylogenetically from ―Macroorganisms‖
For example, many fungi are microorganisms, as
well as all bacteria, all viruses, and most protists.
Microbiology is more a collection of techniques:
• Aseptic technique
• Pure culture technique
• Microscopic observation of whole organisms
A microbiologist usually first isolates a specific
microorganism from a population and then
cultures it.
Types o
f M
icro
org
anis
ms
Bacteria
• a.k.a., eubacteria (―true‖ bacteria)
• a.k.a., domain Bacteria
Archaeabacteria
• a.k.a., domain Archaea
Single-celled members of domain Eukarya.
• Protozoa
• Microscopic Algae
• Microscopic Fungi
Viruses
Types: Bacteria
Description: eubacteria, archaeabacteria, Gram-negative,
Gram-positive, acid fast, cyanobacteria
Types: procaryotes, absorbers, wet conditions, animal
decomposers, cell walls, unicellular
Nutrient Type: chemoheterotrophs, photoheterotrophs,
chemoautotrophs, photoautotrophs
Durable state: endospores (some)
Diseases: tetanus, botulism, gonorrhea, chlamydia,
tuberculosis, etc., etc., etc.
Rob-Shaped Bacteria
Spherical Bacteria
Spiral-Shaped Bacteria
Spirochete
:
Borr
elia
burg
dorf
eri
Types: Cyanobacteria
Description: blue-green algae
Types: photosynthetic aquatic procaryotes, green lake scum,
cell walls
Nutrient Type: photoautotrophs
Durable state: ?
Diseases: none
Types: Algae
Description: photosynthetic aquatic eucaryotes, cell walls, both
unicellular and multicellular types
Types: brown, red, green, diatoms, dinoflagellates, euglenoids
Nutrient Type: photoautotrophs
Durable state:?
Diseases: Some poisonings associated with unicellular types: Alexandrium causes Paralytic Shellfish Poisoning (PSP), Dinophysis causes
Diarrhetic Shellfish Poisoning (DSP), Pseudo-nitzschia multiseries causes
Amnesic Shellfish Poisoning (ASP) [some would describe some as protists]
Types: Fungi
Description: yeasts (unicellular fungi), molds (filamentous
fungi)
Types: eucaryotes, absorbers, dry conditions, plant
decomposers, cell walls, ~100 human pathogens
Nutrient Type: chemoheterotrophs
Durable state: spores
Diseases: mycoses: candida, ringworm (pictured), athlete's
foot, jock itch, etc.
Types: Helminths
Description: Flatworms (platyhelminths), roundworms
(nematodes)
Types: metazoan (multicellular animal) parasites, engulfers
and absorbers
Nutrient Type: chemoheterotrophs
Durable state:?
Diseases:trichinosis, hook worm, tape worm (pictured are
scolex-heads of), etc.
Types: Protozoa (Protists)
Description: Unicellular and slime molds, flagellates, ciliates
Types: eucaryotes, parasites, engulfers and absorbers, wet
conditions, no cell wall, ~30 human pathogens
Nutrient Type: chemoheterotrophs (some classifications
include some photoautotrophs as well)
Durable state: cysts (some)
Diseases: malaria, giardiasis, amoebic dysentery, etc. (shown
are harmless--to us--protist components of pond water:
Amoeba, Blepharisma, Paramecium, Peranema, & Stentor)
Types: Viruses
Description: Not cells but enveloped or non-enveloped
Types: acellular, obligate intracellular parasites
Nutrient Type: not applicable
Durable state: virion particles, some can encase in durable
state of host
Diseases: common cold, flu, HIV, herpes, chicken pox, etc.
Binomial Nomenclature (1/3)
Examples: Escherichia coli, E. coli, Escherichia spp., and ―the
genus Escherichia‖
The genus name (Escherichia) is always capitalized
The species name (coli) is never capitalized
The species name is never used without the genus name (e.g.,
coli standing alone, by itself, is a mistake!)
The genus name may be used without the species name (e.g.,
Escherichia may stand alone, though when doing so it no
longer actually describes a species)
When both genus and species names are present, the genus
name always comes first (e.g., Escherichia coli, not coli
Escherichia)
Binomial Nomenclature (2/3)
Both the genus and species names are always italicized (or
underlined)—always underline if writing binomials by hand
The first time a binomial is used in a work, it must be spelled
out in its entirety (e.g., E. coli standing alone in a manuscript is
not acceptable unless you have already written Escherichia
coli in the manuscript)
The next time a biniomial is used it may be abbreviated (e.g.,
E. for Escherichia) though this is done typically only when
used in combination with the species name (e.g., E. coli)
The species name is never abbreviated
Binomial Nomenclature (3/3)
It is a good idea to abbreviate unambiguously if there is any
potential for confusion (e.g., Enterococcus vs. Escherichia)
These rules are to be followed when employing binomial
nomenclature even in your speech. It is proper to refer to
Escherichia coli as E. coli or even as Escherichia, but it is not
proper to call it coli or E.C.!
Failure to employ correct binomial nomenclature on exams will
result in the subtraction of one point (on 200-Point Scale) per
erroneous usage
When in doubt, write the whole thing out (and underline)!
Various BinomialsBacillus anthracis
Bacillus subtilis
Bdellovibrio spp.
Brodetella pertusis
Chlamydia trachomatis
Clostridium botulinum
Clostridium perfringens
Clostridium tetani
Corynebacterium diphtheriae
Escherichia coli
Gardinerella vaginalis
Helicobacter pylori
Haemophilus influenzae
Klebsiella pneumoniae
Lactococcus lactis
Legionella spp.
Listeria monocytogenes
Borrelia burgdorferi
Mycobacterium leprae
Mycobacterium tuberculosis
Mycoplasma pneumoniae
Neiseria meningitidis
Pasteurella pestis
Proteus vulgaris
Pseudomonas aeruginosa
Rickettsia prowazekii
Rickettsia rickettsii
Salmonella typhi
Serratia marcescens
Shigella dysenteriae
Staphylococcus aureus
Streptococcus pneumoniae
Treponema pallidum
Vibrio cholerae
Yersinia pestis
Neiseria gonorrhoeae
Cheat Sheet (1/2)Bacillus anthracis
Bacillus subtilis
Bdellovibrio spp.
Brodetella pertusis
Chlamydia trachomatis
Clostridium botulinum
Clostridium perfringens
Clostridium tetani
Corynebacterium diphtheriae
Escherichia coli
Gardinerella vaginalis
Helicobacter pylori
Haemophilus influenzae
Klebsiella pneumoniae
Lactococcus lactis
Legionella spp.
Listeria monocytogenes
Borrelia burgdorferi
Anthrax
Not pathogenic
Not pathogenic (to us, at least)
Lyme disease
Trachomas (blindness), etc.
Botulism
Gas gangrene & food poisoning
Tetanus
Diphtheria
Typhoid fever
Vaginitis
Stomach ulcer
Lung, ear infection, meningitis
Atypical pneumoniae (common)
Yogurt
Legionnaire’s disease
Damage to fetus
Whooping cough (pertusis)
Cheat Sheet (2/2)Leprosy
Tuberculosis
Atypical pneumonia
Meningitis
Plague (older name)
Wound infection
Opportunist (e.g., burns)
Typhus
Rocky Mountain Spotted Fever
Typhoid fever
Nosocomial infections
Traveler’s diarrhea
TSS, food poisoning, etc.
Most-common pneumonia
Syphilis
Cholera
Plague (newer name)
Gonorrhea
Mycobacterium leprae
Mycobacterium tuberculosis
Mycoplasma pneumoniae
Neiseria meningitidis
Pasteurella pestis
Proteus vulgaris
Pseudomonas aeruginosa
Rickettsia prowazekii
Rickettsia rickettsii
Salmonella typhi
Serratia marcescens
Shigella dysenteriae
Staphylococcus aureus
Streptococcus pneumoniae
Treponema pallidum
Vibrio cholerae
Yersinia pestis
Neiseria gonorrhoeae
Microbes & Ecology
Microbes are produces—they provide energy to ecosystems
Microbes are fixers—they make nutrients available from
inorganic sources, e.g., nitrogen
Microbes are decomposers—they free up nutrients from no
longer living sources
Microbes form symbioses (such as mycorrhizal fungi
associated with plant roots—though somewhat macroscopic,
the bacteria found in legume root nodules, etc.)
Microbes serve as emdosymbionts (e.g., chloroplasts and
mitochondria)
Microbes & Industry
Industry: Fermentation products (ethanol, acetone, etc.)
Food: Wine, cheese, yogurt, bread, half-sour pickles, etc.
Biotech: Recombinant products (e.g., human insulin,
vaccines)
Environment: Bioremediation
Each carton of Bugs+Plus provides easy to
follow step-by-step instructions, containers of
specially-formulated wet and dry nutrients and
a container of microbes cultured for their
ability to digest oil and other petroleum
derivatives.
Microbes & Disease
Microbes both cause and prevent diseases
Microbes produce antibiotics used to treat diseases
The single most important achievement of modern medicine
is the ability to treat or prevent microbial disease
Most of this course will consider the physiology of microbes
and their role in disease
The Germ Theory of Disease = Microbes cause disease!
(yes, it wasn’t so long ago that humans didn’t know this)
Normal Flora
These are the ~harmless microorganisms found on your body.
Every part of your body that normally comes in contact with
outside world (deep lungs and stomach are exceptions)
Brueghel: The Triumph of Death (1560)
Brief History Microbiology
Anton van Leeuwenhoek (1670s) = microscopy
Edward Jenner (1796) = vaccination against smallpox
Ignaz Semmelweis (1840s) = hand washing before surgery
Louis Pasteur (1860s) = repudiation spontaneous generation
Joseph Lister (1860) = father aseptic surgery
Robert Koch (1870s) = Koch’s postulates
Dmitri Iwanowski (1990s) = Inference of viruses
Alexander Fleming (1920s) = Penicillin
Stephen T. Abedon (2000s) = not one heck of a lot….
Spontaneous Generation Myths
Snakes from horse hairs in stagnant water
Mice from grain and cheese wrapped in a sweater
Maggots from rotting meat
Fleas from hair
Flies from fresh and rotting fruit
Mosquitoes from stagnant pondwater
Eels from slimy mud at the bottom of the ocean
Locusts from green leaves
Raccoons from hollow tree trunks
Termites are generated from rotting wood
Redi’s Experiment
Problems Translating to Microbes
Hard to kill endospores—boiled broths not always sterilized
Concerns (invalid) that boiling altered broths so as to prevent
spontaneous generation
Concerns (invalid) that absence of air prevented
spontaneous generation
Concerns (invalid) that heating or chemically treating air
removed vital force from air thereby preventing spontaneous
generation
Basically, proponents of spontaneous generation had good
ol’ common sense on their side, but since their common sense
did not include any sense of microbiology, these spontaneous-
generation proponents were remarkably incorrect!
Pasteur’s Swan-Necked Flasks
President Garfield’s VertebraeOn the morning of July 2, 1881, Charles Guiteau
fired two shots at President James Garfield as he
entered a Washington, DC train station. One shot
grazed Garfield's hand. The second entered the
President's spine near the right 11th rib but did
not exit.
The x-ray, which would easily have pinpointed the
bullet's location, had not yet been discovered. So
the President's physicians did what all competent
physicians had routinely done in such cases.
They probed the entry wound with special
instruments designed for that purpose - but
without success.
The bullet remained lost inside the President.
Medical historians believe Garfield could have
survived his injury if the attending physicians had
washed their hands and used sterile instruments.
In 1881, though, such antisepsis techniques were
still under debate within the American medical
profession.
MicroDude Comes to Work
Cours
e S
tructu
re Grading:
• 3 midterms (200 points each x 3 = 600 points)
• 1 lab exams (200 points)
• 1 final exam (150 points comp + 150 points non-
comp = 300 points)
• 600 + 200 + 300 = 1100 points
Extra stuff:
• Daily reading and lecture quizzes (½ pt/question)
• ―30% rule‖ on all exam questions
See syllabus for details:
• www.phage.org/school_syllabus.htm
Laboratory PrimerJust reading a lab exercise is not the same as getting ready to
do a lab—you also need to outline for yourself, either mentally
or on paper, just what it is that you will be doing
I know that making such an outline with unfamiliar material is
not easy—that is why you need to look at your lab schedule,
where I attempt to guide you through what it is that you will
need to be doing
You have to try to remember that a culture that has settled will
need to be resuspended—and you have to not just go through
the motions: you actually need to resuspend it!
It may be that some of you have not had previous training in
using a microscope; after class today we therefore will have a
―microscope 101‖ session in B211
Acknow
ledgem
ents
http://www.colby.edu/biology/BI163/Bacteriappt/bacteriaarchaea.ppt