Module 1 Flashcards
Study of organisms and agents too small to be seen by the naked eye (<1mm)
Microbiology
new definition of microbiology
“The study of organisms that can exist as single cells (others are acellular), contain a nucleic acid genome for at least some part of their life cycle, and are capable of replicating that genome.”
one of the larger microbes, lives in the gut of
sturgeonfish
Epulopiscium fishelsoni
purpose of Epulopiscium fishelsoni
regulates pH of sturgeon fish (Acanthurus lineatus)
largest microbe in 2018, 98% are composed of vacuoles as it requires it to store Sulfur
Thiomargarita namibiensis
largest microbe right now, found in Caribbean coast
Thiomargarita magnifica
measurement of Thiomargarita namibiensis and Thiomargarita magnifica
1800 um and 9000 um
The science of microbiology revolves around two interconnected themes:
- Understanding the living world of microscopic organisms (as a basic biological science)
- Applying our understanding of microbial life processes for the benefit of humankind and planet Earth (as an applied biological science)
Importance of microorganisms
first living organisms on planet
live everywhere life is possible
more numerous than any other kind of organisms
global ecosystem depends on their activities
influence human society in many ways
Interest in specific group of microorganisms
and their biology
Basic Microbiology
study of viruses
Virology
study of fungi
Mycology
study of protozoa
Protozoology
study of algae
Phycology
study of bacteria
Bacteriology
Applying our understanding of microbial life processes for the benefit of humankind and planet Earth
Applied Microbiology
Applied Microbiology fields include (but are not limited to) the following
Medical Microbiology
Immunology
Public Health Microbiology
Food & Dairy Microbiology
Industrial Microbiology
Agricultural Microbiology
Microbial Ecology
scientific name of yeast
Saccharomyces cerevisiae
- Infected with the eggs of the parasite Trichuris trichiura, which may have caused him to have abdominal pain and anemia
- Possible infection with Borrelia burgdorferi, a bacterium that causes Lyme disease
- Some researchers think Ötzi may have been trying to treat his infections with the woody fruit of the Piptoporus betulinus fungus. This fungus has both laxative and antibiotic properties.
Ötzi the Iceman
Ancient Greeks and Romans attributed disease to
bad air, mal’aria, which they called “miasmatic
odors.”
Greek physician, Father of Western Medicine; believed that microorganisms are the culprit of diseases
Hippocrates
believed in evidence-based cause and effect
Thucydides
believed that microorganisms also contribute to pathogenic diseases
Marcus Terentius Varro
invented the first compound microscope (3-10x)
Zacharias Janssen
suggested to be the first to observe microorganisms
Athanasius Kirche
“wee animalcules”; refuted spontaneous generation theory
Antonie van Leeuwenhoek
simple compound microscope (30x); wrote Micrographia; first to see fruiting bodies of mold (“cells” in cork) and fungi (“elongated stalks”)
Robert Hooke
qLife emerges from non-living matter; “vital force” required
Spontaneous Generation Theory
founder of experimental biology; demonstrated the use of controlled experiment; disproved that maggots can be generated from meat
Francesco Redi
claimed that microorganisms in broth developed independently of other cells; first to do the broth experiment; believed in spontaneous generation
John Needham
proposed that microorganisms could have entered the flask after boiling but before sealing, and to test this, he conducted an experiment where he sealed the flask before boiling. In his experiment, no microorganisms grew, supporting the idea that spontaneous generation did not occur under those conditions. however, Spontaneous Generation supporters claimed that air was required
for the vital force to work!
Lazzaro Spallanzani
passed air through strong acids which resulted in no growth of microorganisms
Franz Schultze
passed air through red-hot tubes which resulted in no growth of microorganisms
Theodor Schwann
filtered air through sterile cotton wool which resulted in no growth of microorganisms; did the first basic technique of plugging
Georg Friedrich Schröder and Theodor von Dusch
- Experiments with Swan-neck flasks
- Results proved that life did not arise from nonlife
Louis Pasteur
Pasteur’s test of spontaneous generation
Pasteur kept some food isolated from the outside and noticed it didn’t spoil. When he exposed it to the outside air, it spoiled. This showed that life doesn’t just appear on its own. Pasteur’s experiment proved that the spoilage was caused by tiny particles in the air, not the air itself.
He designed a swan-necked flask, which allowed air to enter but prevented dust and microorganisms from reaching the broth inside. The flask was boiled to kill any existing microorganisms, and as long as the flask’s neck remained intact, no microorganisms appeared in the broth, even over an extended period. This experiment demonstrated that spontaneous generation did not occur under these controlled conditions, and it supported the idea that living organisms come from pre-existing life. Pasteur’s work played a crucial role in refuting the long-standing belief in spontaneous generation and promoting the concept of biogenesis.
➢ demonstrated that dust carries microorganisms
➢ also provided evidence for the existence of exceptionally
heat-resistant forms of bacteria
➢ Developed the process tyndallization
John Tyndall
a form of sterilization that involves boiling the goods to be sterilized in their cans or jars at 100 degrees Centigrade for about 15 to 20 minutes a day, for three days in a row.
tyndallization
Diseases are caused by specific agents called germs
GERM THEORY OF DISEASE
epidemics/disease was caused by invisible living creatures
Girolamo Fracastoro
showed that a disease of silkworms was caused by a fungus; associated disease to germs
Agostino Bassi
demonstrated that the Great Potato Blight of Ireland was caused by a fungus (Phytophthora infestans)
Miles Joseph Berkeley
- showed that smut and rust fungi caused cereal crop diseases
- “Founding father of Plant Pathology and Founder of Modern Mycology”
Heinrich Anton de Bary
▪ asepsis in obstetrical wards to prevent the transmission of childbed fever from patient to patient
▪ policy for all attending physicians to wash their hands with chlorinated lime solutions (calcium hypochlorite) between patients
▪ mortality rate dropped from 18% to 2.4%
▪ savior of mothers
Ignaz Philipp Semmelweis
▪ provided indirect evidence that microorganisms were the causal agents of disease
▪ used phenol or carbolic acid in surgical dressings and heat-sterilized surgical instruments
▪ “Father of Antiseptic Surgery”
▪ prevented post-operatic infections
Joseph Lister
showed that the pébrine disease of silkworms was caused by a protozoan
Louis Pasteur
✓established the relationship between Bacillus anthracis and anthrax (the disease)
✓used criteria developed by his teacher, Jakob Henle (1809-
1895)
Robert Koch
“Koch’s Postulates”
1 The suspected causative agent must be absent from all healthy organisms but present in all diseased organisms.
2) The causative agent must be isolated from the diseased organism and grown in pure culture.
3 The cultured agent must cause the same disease when
inoculated into a healthy, susceptible organism.
4. The same causative agent must then be reisolated from the inoculated,
diseased organism.
Koch’s work led to the development of:
solid culture media, pure culture maintenance, aseptic technique, petri plate (Richard Petri)
Koch’s Postulates Limitations
✓ Causative agents of several human diseases do not cause disease
in any known experimental animals.
✓ Some microbes are obligate intracellular parasites (like
chlamydia and viruses) and are very challenging, or even
impossible, to grow on artificial media.
✓ Some diseases, such as tetanus, have variable signs and
symptoms between patients.
✓ Some diseases, such as pneumonia & nephritis, may be caused
by a variety of microbes.
✓ Some pathogens, such as S. pyogenes, cause several different
diseases.
✓ Certain pathogens, such as HIV, cause disease in humans only - it is unethical to purposefully infect a human.
the deliberate infection with smallpox. Dried smallpox scabs were blown into the nose of an individual who then contracted a mild form of the disease. Upon recovery, the individual was immune to smallpox.
variolation
- used a vaccination procedure to protect individuals from
smallpox - Used pus from cowpox blisters to inoculate
- Cowpox virus is closely related to variola, the causative agent of smallpox
Edward Jenner
Pasteur and his co-workers developed vaccines for
▪ chicken cholera (Charles Chamberland inoculated some chicken)
▪ anthrax
▪ rabies (attenuation)
- incubation of cultures for long intervals between
transfers caused pathogens to lose their ability to cause
disease - growing the pathogen in an unnatural host weakens it
Attenuation
developed porcelain bacterial filter that had tiny pores that allowed fluids to pass through while holding back bacteria and other microorganisms
Charles Chamberland
- considered one of the founders of virology
- In 1898, published results on the filtration experiments demonstrating that tobacco mosaic disease is caused by an infectious agent smaller than a bacterium, which he
called “virus” - “contagium vivum fluidum” (contagious living fluid)
Martinus Beijerink
developed 606th compound SALVARSAN (organic arsenical to treat syphilis)
Paul Ehrlich
discovered the “miracle drug” penicillin from Penicillium
Alexander Fleming
▪ Demonstrated the role of yeasts in fermentation
▪ Fermentations were the result of microbial activity
▪ Alcohol fermentation by yeasts
▪ Lactic acid fermentation by bacteria
▪ developed the process of pasteurization to preserve wine
Louis Pasteur
- fermentation could occur in yeast extracts free of cells
- cell-free extract or “juice”
Eduard Buchner
discovered the existence of heat-resistant bacterial endospores
Ferdinand Cohn
✓ studied soil and soil microorganisms
✓____ discovered nitrogen fixation
✓____ discovered lithotrophy and chemoautotrophy
✓ developed enrichment cultures and selective media
Sergei Winogradsky
Martinus Beijerinck
