The Science of

MicrobiologyCRYSTAL GARCIA

What is Microbiology?

Microbiology is a specialized branch of biology that studies living organisms, too tiny to be viewed with the unaided eye.

It’s focus of study are referred to as Microbes or Microorganisms

Microorganisms live in every part of the biosphere (and the vacuum of space) and play a role in all of the most essential processes of life including Photosynthesis, decomposition and recycling of chemical nutrients (e.g. nitrogen fixation)

How is the scientific method

used in Microbiology? Generally, microorganisms are isolated from

their environment and studied in a lab under a

microscope.

They are then classified into groups using

Taxonomy’s Domains of Life system which

recognize and identify them by specific

characteristics. Microorganisms are then

provided with standard scientific names.

The History of Microbiology

Set in motion in the late 16th century with the

creation of the compound microscope by

Robert Hook and contemporaries

Simple microscope-like instrument created by

Antoine van Leeuwenhoek

Antoine van Leeuwenhoek

(1632-1723)

Antoine van Leeuwenhoek

A Dutch fabric merchant - Leeuwenhoek

originally intended his instrument to examine

cloth fabric for flaws.

His device would allow microbes to be

observed and analyzed for the first time in

human history.

Often referred to as “the father of Microbiology”

though he was incredibly secretive with the

construction of his microscope

Louis Pasteur (1822–1895)

biography.com - Louis Pasteur

Louis Pasteur

French Chemist considered one of the major

founding fathers of Microbiology

Best known for creating Pasteurization -

technique of heating then cooling liquids to slow

bacterial growth

Would ultimately demonstrate the importance

of “proofs” as well as observation and

experimentation which are the cornerstone

principles of science.

Spontaneous Generation

Theory on the formation of living things

Persisted from archaic times until approx. the 17th and 18th century

Proposed that living things formed from non-living matter

Religious connotation related to the origin of life on Earth

would have both heated proponents and opponents in the scientific community

“”

Pasteur would take a logical stance on the subject and demand that more evidence be produced before this theory could be referred to as Scientific Fact

I think, Sir, that you are in the wrong, not because

you believe in spontaneous generation, since it is

difficult in such matters not to have a preconceived

idea, but in stating that spontaneous generation

exists. . . . In my estimation the whole question still

lacks proofs. . . .

Pasteur and “Spontaneous

Generation”

Pasteur would devise an experiment that would ultimately disprove this theory.

Invented the swan neck flask which would be the key element in disproving Spontaneous Generation

With this instrument Pasteur would set sterile liquid in an intricately curved flask, allowing it to be exposed to air without the risk of contamination from dust particles or microorganisms in the air.

Pasteur and “Spontaneous

Generation”

How is Microbiology helpful and

useful to people?

You Can Thank Microbiology For:

Germ Theory - a theory in medicine: infections,

contagious diseases, and various other

conditions result from the action of

microorganisms (merriam-webster)

(Medical) Sterilization – any process that

eliminates (removes) or kills all forms of life

(Wikipedia)

You Can Thank Microbiology For:

Vaccinations - a preparation of killed

microorganisms, living attenuated organisms, or

living fully virulent organisms that is administered

to produce or artificially increase immunity to a

particular disease (merriam-webster)

Pasteurization - a process in which a liquid (such

as milk or cream) is heated to a temperature

that kills harmful germs and then cooled quickly

(meriam-webster)

They’re literally everywhere.

Aid in animal digestion

Used in food production and fermentation (e.g. dairy products, wine, yeast)

Used for many commercial and industrial production of chemicals, enzymes and other bioactive molecules (e.g Citric acid which is produced by a certain type of fungus)

Used in sewage treatment as well as energy fermentation (e.g. ethanol)

Taq polymerase and its influence

on Genetic Engineering

Enzyme isolated from the thermophilic, “Heat-

Loving”, bacterium Thermus aquaticus.

Used as a key enzyme in the denaturing process

of the Polymerase chain reaction (technique

used to make multiple copies of a segment DNA

of interest)

Responsible for advances in genetic

engineering, such as DNA testing, cloning and

sequencing

Bioremediation

Bioremediation is a waste management

technique that involves the use of organisms to

remove or neutralize pollutants from a

contaminated site. According to the EPA,

bioremediation is a “treatment that uses

naturally occurring organisms to break down

hazardous substances into less toxic or non toxic

substances”.

Bioremediation

(Left) Alaska. Workers outfitted in safety attire spray benign nutrients for Bioremediation Project on

the Exxon Valdez oil spill in Prince William Sound.

Info from the Environmental

Protection Agency on

Bioremediation Some types of microbes eat and digest

contaminants, usually changing them into small amounts of water and harmless gases

(cannot always be treated in situ) It may take a few months or even several years for microbes to clean up a site, depending on several factors.

Bioremediation relies on microbes that live naturally in soil and groundwater. These microbes pose no threat to people at the site or in the community.