Microbiology in the Biological WorldMicrobiology in the Biological World

Why study Microbiology?Why study Microbiology?

1. Helps us to understand 1. Helps us to understand life forms by life forms by understanding understanding ones.ones.

2. 2. of infectious diseases of infectious diseases (Small pox, Typhoid fever, (Small pox, Typhoid fever, Cholera).Cholera).

3. Various3. Various ..

Evolution of MicrobiologyEvolution of Microbiology

1.1. was was the first to observe the the first to observe the microscopic world with microscopic world with a 3X microscope a 3X microscope (1632-1723). (1632-1723).

2.2. - - Observed cork & Observed cork & termed the word termed the word

“ “ ””..

2. Theory of Spontaneous Generation (SG). Organisms appeared out 2. Theory of Spontaneous Generation (SG). Organisms appeared out of no where.of no where.Ex. If meat was left out flies appeared.Ex. If meat was left out flies appeared.

A. A. - disproved (SG) in higher organisms but not in - disproved (SG) in higher organisms but not in microorganisms.microorganisms.

B. B. - supported (SG) in microorganisms. - supported (SG) in microorganisms.• After sterilization (Boiling) microorganisms still arouse.After sterilization (Boiling) microorganisms still arouse.

C. C. - disproved (SG) by conducting an experiment - disproved (SG) by conducting an experiment using bottle swan neck flask.using bottle swan neck flask.

Proved that dust must carry microorganisms.Proved that dust must carry microorganisms.

D. D. - dust carries bacteria that can grow after - dust carries bacteria that can grow after heating -heating - - heat stable form of bacteria. - heat stable form of bacteria.

3. Fermentation3. Fermentation

- First problem as a - First problem as a microbiologist was to discover why the production microbiologist was to discover why the production of alcohol from sugar beets would occasionally of alcohol from sugar beets would occasionally produce lactic acid.produce lactic acid.

DISCOVERED two types of bacteriaDISCOVERED two types of bacteria

1.1. - required for - required for survivalsurvival

2.2. - does require - does require oxygenoxygen

4. Germ Theory4. Germ Theory1834 - first time disease was linked to an microorganism.1834 - first time disease was linked to an microorganism.

A. - disease in silk worm was a result in a fungus A. - disease in silk worm was a result in a fungus infection.infection.

B. - 1865 - similar work.B. - 1865 - similar work.

C. - credited with the first attempt to prevent C. - credited with the first attempt to prevent post surgical infection by using diluted phenol.post surgical infection by using diluted phenol.

D. - developed rules to establish a cause & effect D. - developed rules to establish a cause & effect relationship between an microorganism & a disease.relationship between an microorganism & a disease.

• Koch’s PostulatesKoch’s Postulates1. 1. 2. 2. 3. 3. 4. 4.

Microbiology Microbiology Stepping Stepping StonesStones

Divisions of MicrobiologyDivisions of Microbiology

1. - study of microorganisms 1. - study of microorganisms that cause disease in humans & animals.that cause disease in humans & animals.

2. - reaction of a host to the 2. - reaction of a host to the infection.infection.

3. 3. -alcohol beverages, -alcohol beverages, antibodies.antibodies.

4. - harmful or beneficial to 4. - harmful or beneficial to the production of agricultural products.the production of agricultural products.

5. - recombinant DNA. Human 5. - recombinant DNA. Human insulin. Synthesis of vaccine.insulin. Synthesis of vaccine.

Medical Microbiology Past TriumphsMedical Microbiology Past Triumphs

1. Small Pox1. Small Pox Viral disease - 10 Viral disease - 10 million peopled diedmillion peopled died

No cases reported since 1977No cases reported since 1977

2. Bubonic Plague Bacterial 2. Bubonic Plague Bacterial Disease - 25 million people diedDisease - 25 million people died

100 people die/year from it100 people die/year from it

Future ChallengesFuture Challenges

Not all diseases are under control.Not all diseases are under control.

1. million cases of infections /year in US (22,000 1. million cases of infections /year in US (22,000 deaths)deaths)

2. Lyme disease, ’, AIDS, Hantavirus.2. Lyme disease, ’, AIDS, Hantavirus.

3. New diseases may emerge ( ).3. New diseases may emerge ( ).

4. Old diseases are on the increase in US 4. Old diseases are on the increase in US

A. Travelers from foreign countries - 1 in 5 vistor’s A. Travelers from foreign countries - 1 in 5 vistor’s come come from a country with Malaria, Yellow fever, & Cholera.from a country with Malaria, Yellow fever, & Cholera.

B. Resistant microbes.B. Resistant microbes.

C. Medicines are increasing the life span, therefore C. Medicines are increasing the life span, therefore immune system weakens in elderly people.immune system weakens in elderly people.

D. Children in developing countries were under D. Children in developing countries were under controlled controlled (mumps, whooping cough, measles). Parents (mumps, whooping cough, measles). Parents lax about lax about vaccinating children.vaccinating children.

Cell Theory1. Cell is the fundamental unit of life & cells come from pre-existing cells (1839 - Schleiden & Schwann).

Similarity in Function & Composition of CellsAll cells have the same problems:

1. Reproduce copies of itself.2. Obtain & use for reproduction.

Solutions1. - protein molecules to speed up chemical reactions.2. - genetic information.3. - protein synthesis.4. - energy.5. - help enzymes.6. - building blocks of proteins.

Origin of Life

First form of life appeared about .

Earth’s environment High temperature, , & lighting

catalyzed to formed amino acids (AA).

Proven by Conducted experiments where he replicated early Earth’s environment & by inducing a spark ’s were formed.

Eventually over time• => => =>

Other organic compounds were mixed in until a being developed capable of directing synthesis of simple organic molecules.

In time self replication - .

ProkaryoticProkaryotic

First cells were Prokaryotes, then over time developed into Eukaryotes.

Prokaryotes Eukaryotes1. No intracellular . 1. Intracellular membranes

present (organelles).

2. present with 2. Cell membrane always . present with cell .

3. . 3. .• DNA not separated DNA was separated from the rest

from the rest of of the cell.the cell

4. DNA - 4. DNA -proteins –

5. DNA continuous thread. 5. DNA separated into chromosomes. of chromosomes

dependent on the species.

6. Reproduce - 6. Reproduction & Binary fission. .

Prokaryotic vs EukaryoticProkaryotic vs Eukaryotic

ProkaryotesEukaryotes

Prokaryotes can be divided into two major groups.1. (true bacteria) 2. - grow in hostile environments, but little

micorbiolgical importance.

Microbial world

study of all prokaryotes & unicellular eukaryotes.

Kingdom Monerans and Archaebacteria

- Algae & Protozoans • Reproduction sexual & asexual

- smaller than protozoans & are the major cause of diseases.• Cyanobacteria - photosynthesis

- large multicellular eukaryote worms (flat & round).

DomainsDomains

- filamentous & unicellular eukaryotic cells. Some cause diseases.

- 1 cell fungus, budding spores, breads & alcoholic beverages, few produce human diseases.

- Multicellular, asexual & sexual spores, flavor fine cheeses, few produce human diseases.

Infectious Agents

- Smallest known disease agent.• DNA or RNA surrounded by a

protein coat. Bacteriophages - infect bacteria.

- small piece of RNA that does not have a protein coat.

- Proteins without DNA or RNA.

Microbial world

Microbial world

Microbial world

Cell SizeCell Size