Introduction to Microbiology Flashcards
Name a ‘superbug’
MRSA
What does streptococcus pyogenes do?
Necrotising bacteria
Eats flesh
What does the term ‘microorganism’ encompase?
Bacteria
Viruses
Fungi: yeasts, moulds
Parasites and algae
Who is the founder of the field of bacteriology?
Ferdinand Cohn
Who are the two fathers of microbiology?
Louis Pasteur
Robert Koch
What did Louis Pasteur do?
He disproved the idea of spontaneous generation
How did Louis Pasteur disprove spontaneous generation?
5
He got two sterile flasks filled with a medium
One was placed upright the other on its side
Bacteria couldn’t get by the bend in the neck of the upright flask and couldn’t colonise the medium
Bacteria could reach the medium in the medium in the neck of the sideways flask
This refuted the idea that cells can arise spontaneously from nonliving matter
Other than disprove spontaneous generation what did Pasteur do?
(3)
He proposed that if food were treated so as to destroy all living organisms and protected from further contamination, it would not putrefy
This led to the development of effective sterilisation such as ‘pasteurisation’
He also developed vaccines for anthrax and rabies
What two diseases did Pasteur make vaccines for?
Anthrax
Rabies
On what basis did Pasteur make his vaccines?
His notion that a ‘weak form’ of an infection might cause immunity to the virulent form
What was Robert Koch’s main contribution to microbiology?
2
The Germ Theory of Disease
and therefore Koch’s Postulates
What are Koch’s postulates?
A sequence of experimental steps to relate a specific microbe to a specific disease
How did Koch prove his germ theory of disease?
2
When working with bacteria that causes anthrax he showed that a small amount of blood from a diseased animal could transfer the disease to a previously healthy mouse
He also found that the bacteria could be grown outside of the mouse and still caused disease when re-inoculated into another mouse
What are the four steps to Koch’s postulates?
4
The suspected pathogenic organism should be present in all cases of the disease and absent from healthy animals
The suspected organism should be grown in pure culture
Cells from a pure culture of the suspected organism should cause disease in a healthy animal
The organism should be re-isolated and shown to be the same as the original
List Koch’s main contributions to microbiology.
5
Discovered the cause of tuberculosis, Mycobacterium tuberculosis
Developed methods for bacterial staining
Improved methods for bacterial growth (Agar plates)
Created pure cultures and began to characterise bacteria
Improved bacterial purification techniques and urged the sterilisation of surgical instruments with heat
What bacteria did Koch discover?
Mycobacterium tuberculosis
Why did it take us until the 1930s to expand work on viruses?
As this was when the electron microscope was invented
What major work was done in 1929?
Alexander Fleming discovered penicllin
Give five areas in life where microorganisms play a major role.
Health
Agriculture
food
Environment
Biotechnology
What name is given to microbes with a protect role to man?
Microbiome
What name is given to microbes that cause infectious disease?
Pathogens
How do we control infectious diseases?
3
Understanding the disease processes of different pathogens
Improved sanitary and infection control practices
Discovery of antimicrobial agents and vaccines
How do microorganisms remain major threats to health?
5
New pathogens are always emerging e.g. Ebola and Covid-19
Current pathogenic organisms continue to cause serious infection
Increasing numbers of immuno-compromised patients susceptible to infection
Many pathogenic organisms resistant to action of antimicrobial therapy
Increasing amount of life-saving invasive procedures
What four categories of products are made by microorganisms?
Foods
Alcoholic beverages
Chemicals
Antibiotics
How do microorganisms play a role in energy production?
Natural gas (methane) is a product of bacterial activity
What is bioremediation?
The use of microbes to clean up toxic spills
Explain the relationship between microorganisms and biotechnology.
Biotech involve the use of microorganisms in industrial biosynthesis, typically by organisms that have been genetically modified to synthesize products of high commercial value
E.g. production of human insulin
How are microorganisms used in genetics?
2
Used in genetic engineering as tools for the artificial manipulation of genes in cells
Used in gene therapy whereby an absent or faulty gene is replaced by a working gene
Give a use of gene therapy.
Used to treat sickle cell anaemia and cystic fibrosis
