Intro to Microbiology (Module 1)

microorganisms

organisms too small to be seen with naked eye

microbes include

bacteria, fungi, protozoa, microscopic algae, viruses

pathogenic definition

disease producing

what do microbes do with organic waste?

decompose it

how do microbes help generate oxygen?

photosynthesis

what chemical product is made by microbes?

ethanol

which food is made using microbes?

vinegar

which manufacturing product is made using microbes?

cellulase

which medical product is made using microbes?

insulin

scientific names for microbes are either ____

italicized or underlined

the genus of microbes

is capitalized, the species is lower case

three domains for microbio

bacteria, archaea, eukarya

six subgroups of microorganisms (based on cell type/physiology)

bacteria, archaea, fungi, protozoa, algae, and viruses

bacteria

prokaryotes, Peptidoglycan cell walls, Binary fission

what do bacteria use for energy?

organic chemicals, inorganic chemicals, or photosynthesis

archaea

Prokaryotic, Lack peptidoglycan, Live in extreme environments

fungi (yeasts & mold)

Eukaryotes, chitin cell walls

what do fungi use for energy?

organic chemicals

Molds and mushrooms are

multicellular, made of mycelia (which consist of hyphae)

yeasts are

unicellular

protozoa

eukaryotes, Absorb or ingestorganic chemicals
- can move via pseudopods, cilia, or flagella

algae

eukaryotes, cellulose cell walls

what does algae use for energy?

photosynthesis

what does algae produce?

molecular oxygen and organic compounds

viruses

a non-cellular, infectious particle that must infect a host cell to reproduce.

viruse cores are surrounded by a ___

protein coat or lipid envelope.

multicellular animal parasites

eukaryotes, multicellular animals - but are considered microorganisms

Van Leeuwenhoek

first to see microorganisms

Edward Jenner

realized cowpox infection protected cows from smallpox.

Ignaz Semmelweiss

introduced prevention of fatal childbed fever with physician hand and instrument sanitation

spontaneous generation

living organisms arise through non-living matter

Abiogenesis

Life is formed from inanimate objects

Francesco Redi

Argued against SG: proved maggots grew only from fly eggs

John Needham

Argued for SG: boiled broth and saw microbes develop

Lazzaro Spallanzani

Argued against SG: used a sealed flask and saw no growth

Louis Pasteur

disproved SG: showed microorganisms come from airborne dust, not from non-living matter.

Why is resolution more important than magnification in microscopy?

resolution allows us to easily distinguish between the small parts of a cell

Robert Koch

discovered bacteria

Iwanowksi

discovered viruses

Ehrlich

developed staining techniques, selective toxicity

Fleming

discovers penicillin

Carl Woese

discovered archaea

Germ Theory of disease

scientific theory that states that microorganisms, such as bacteria, viruses, and parasites, are the primary cause of infectious diseases

Koch’s 1st postulate

same microbes always present in samples of diseased animal

Koch’s 2nd postulate requires

isolating and growing microorganism/microbe in pure culture

Koch’s 3rd postulate

pure culture causes same disease in test animals

Koch’s 4th postulate

re-isolate same microbe from sick test animals

Additional Pasteur accomplishments

microbial fermentation, disproved SG, developed pasteurization, rabies vaccine, aseptic lab techniques.

What is Microbiology Today mainly about?

Basic biology and study of microorganisms

Microorganisms share metabolism and genetic properties with which groups?

plants and animals

Why are microorganisms suited for experimental investigation?

They are easy to grow and study

What is Immunology?

An independent, fast-developing science (study of the immune system)

What does Virology study?

viruses

What is Genomics used for?

Identification, disease research, and vaccine development

What does Recombinant DNA lead to?

Biotechnology

Biotechnology using E. coli can make which products?

Pharmaceuticals such as insulin and growth hormone

Microbes normally present in and on the human body are called

normal microbiota

How do normal microbiota help the body?

They prevent the growth of pathogens

What do normal microbiota produce?

Growth factors such as vitamins B and K

What is resistance in microbiology?

The ability of the body to ward off disease

What are examples of resistance factors?

Skin, stomach acid, and antimicrobial chemicals

What is a biofilm?

microbes that attach to solid surfaces and grow into masses

where can biofilms grow?

rocks, pipes, teeth, and medical implants

What problems can biofilms cause?

infection

Why are biofilms hard to treat?

They are resistant to antibiotics and other antimicrobial treatments

what is one beneficial role of biofilms?

They protect mucous membranes from harmful organisms

How do biofilms help in aquatic ecosystems?

They provide food in aquatic ecosystems

What is one harmful effect of biofilms?

They can clog water pipes

Why are biofilms dangerous on medical implants?

they cause infections and are resistant to antibiotics

Emerging Infectious Diseases (EIDs)

new diseases and diseases increasing in incidence

e coli

escherichia coli

s aureus

staphylococcus aureus

writing scientific names for microbes

Genus capitalized , the specific epithet ‘species’ is lower case.

neisseria

gonorrhoeae

bacillus

anthracis

myobacterium

tuberculosis

treponema

pallidum

proteus

vulgaris

acid fast stain

developed for Mycobacterium tuberculosis

acid fast

Cells that retain a basic stain in the presence of acid-alcohol

Non–acid-fast cells

lose the basic stain when rinsed with acid-alcohol

negative staining

useful for capsules

endospore stain

heat is required to drive a stain into endospores

flagella staining

requires a ‘mordant’ to make the flagella wide enough to see.

Sterilization

involves eliminating all microorganisms

Why must culture media be sterilized?

To eliminate all microorganisms and prevent contamination

What are the two main types of heat sterilization?

Moist heat (autoclave: 121 °C for 20 min) and dry heat (glassware: 170 °C for 90 min)

What is an example of chemical sterilization?

Ethylene oxide gas

What is the goal of aseptic techniques in culture transfer?

To obtain pure cultures

What method is used to isolate pure cultures on plates?

The streak plate method

What must be done to the loop between streaks in the streak plate method?

Sterilize the loop

What is a defined culture medium?

A medium with known ingredients and known amounts (made from pure chemicals/compounds)

What is complex medium made from?

Extracts of natural sources such as beef, blood, milk, protein, yeast, or soybeans (precise composition not known)

What is selective media used for?

To chemically select for specific microorganisms while inhibiting others

What is differential media used for?

To identify and distinguish microorganisms

What is liquid culture medium called?

broth

What gelling agent is most used to solidify media?

Agar (a complex polysaccharide)

Why is agar ideal as a solidifying agent?

It is generally not metabolized by microbes

At what temperature does agar liquefy?

100 °C

At what temperature does agar solidify?

~40 °C