Quiz # 21. Complete the table: (10 points)

group of M.O. uni/multicellular

prokaryotic/ eukaryotic

specific name of study

(bonus, 0.20 points each)

2. Name the associated M.O. with the following conditions: gastric ulcer, diabetes, female infertility (3 points)

3. Differentiate between 1st Golden Age of MCB and 2nd Golden Age of MCB (2 points)

HISTORICAL OVERVIEW

OF MICROBIOLOGY

fossils of m.o. found in Australia date back to 3.5 BILLION years ago, whereas H. sapiens only appeared very recently

Infectious Diseases

studies of mummies and fossils:

syphilis, TB, schistosomiasis, tapeworm infection existed for as long as humans and animals existed

records of epidemics

•Egypt, 3100 BC, pestilence

•Thebes, Egypt, 1500 BC, epidemic fevers

•China, 1122, small pox

significant events in the science of MCB

1.development of microscope

2.use of scientific method

3.development of medical microbiology including the germ theory

4.development of modern microbiological techniques

diseases were cloaked in mystery

and regarded with superstition

1. development of microscope

Robert Hooke:

•studied great diversity of materials from plants

•first described the cellular structures of tree barks

•drew sketches and described “little structures” that seemed to be alive

microscopes

Anton Van Leeuwenhoek

•no formal training in science

•first person to see bacteria and protozoa

•“Father of MCB/ bacteriology/protozoology

•hobbyist, made more than 500 microscopes with up to 300x mag

permitted the awareness of widespread distribution of MO

examined scrapings from teeth, pond water, blood, sperm, diarrheal stool

•sent letters to Royal Society of London

•did not share his method for grinding or examining

“My method for seeing the very smallest animacules I do not impart to others; now how to see very many animacules at one time. This I keep to myself alone.”

modern day microscopes:

1000x magnification

but basic structure and function are not greatly different

2. use of scientific method

development of experimental system answered questions objectively (vs. superstition)

fall of superstition/ rise of MCB

Theory of Spontaneous Generation/ Abiogenesis

★living things arise from non- living things

★reinforced by observations of maggots coming out of meat, mushrooms growing on woods

★debated for 200 years

“animacules”

•considered to be early stages in development of more complex organisms

experiment by Francesco Redi

experiment by Louis Pasteur

Louis Pasteur

•French chemist

•contributions are foundations of MCB and cornerstone of modern medicine

significant events in the science of MCB

1.development of microscope

2.use of scientific method

3.development of medical microbiology including the germ theory

4.development of modern microbiological techniques

contributions1.disproved the spontaneous generation

2.discovered what occurs during alcoholic fermentation, and that different MO produce different products

• yeast: ethyl alcohol

• acetobacter: acetic acid

3.developed pasteurization

• 55 degrees centigrade for several minutes

• present times: 63- 65 for 30 minutes or 73- 75 for 15 seconds

contributions3. discovered the infectious agent that causes silkworm diseases and how to prevent such diseases

4. championed changes in hospital practices (along with Joseph Lister)

5. contributed to the germ theory of diseases, which states that specific MO cause specific diseases

ex: B. anthracis: anthrax

Dr. OLIVER HOLMES

• observe less infection in mothers giving birth in homes than in hospitals

Dr. IGNAZ SEMMELWEIS

• observed more infection in women examined immediately after doctors come out of autopsy rooms

• linked MO to diseases

3. development of medical microbiology including the germ theory

JOSEPH LISTER

• introduced aseptic technique for medical settings

ROBERT KOCH

• formulated the KOCH’S POSTULATES

3. development of medical microbiology including the germ theory

Koch’s Postulates

•a series of proofs that:

•verify the germ theory of diseases

•establish whether an organism was pathogenic

•establish the disease an organism causes

1. a particular M.O. must be present in all cases of the disease, and not present in healthy animals

2. M.O. must be isolated and grown pure

3. and 4. same disease must be produced when a healthy animal is inoculated with culture

5. same M.O. must be recovered from experimentally infected animal

KOCH’S Postulate

•stressed use of lab culture and identification of microorganisms

•R. Koch: invented inoculation, isolation, media, maintenance of pure cultures, and preparation of specimen

•Colleagues:

•R. J. Petri: invented flat glass disk in which to culture bacteria

•Frau Hess (wife of colleague): suggested use of agar (polysaccharide from seaweed)

4. development of modern microbiological techniques

exceptions to Koch’s Postulates

certain pathogens do not grow on artificial medium,ex: MO for syphilis, leprosy --obligate intracellular pathogens require living host cells, therefore propagate M. leprae in armadillos, Treponema pallidum for syphilis in testes of rabbitsmany pathogens are species-specific

some diseases are synergistic infections, caused by 2 or more M.O.. ex: acute necrotizing ulcerative gingivitis and bacterial vaginosissome pathogens become altered when grown in vitro, i.e. less or non-pathogenic

some diseases are not caused by MO