Unit 3 Microbiology

Microaerophiles

Require oxygen to grow, but in lower concentrations than contained in air. These microbes contain SOD and catalase but at lower levels/concentration.

Aerotolerant Anaerobes

Can grow with O2, but grows best without O2. Microbes in this classification have SOD but not catalase.

Obligate Anaerobes

Molecular/Atmospheric O2 is toxic because they lack both SOD and catalase.

Facultative Anaerobes

Can grow without O2, but prefer O2 due to possessing both SOD and catalase enzymes as well as being fermentative.

Obligate Aerobes

Require O2 and can't grow without it. These microbes contain both SOD and catalase.

Superoxide free radicals

Toxic radical .O2- that is a byproduct of cellular respiration.

Hydrogen Peroxide

H2O2

Carbon and Hydrogen

A chemical requirement for life found in all macromolecules within microbes.

Nitrogen

A chemical requirement for life found in amino acids and bases found in DNA and RNA.

Phosphorus

A chemical requirement for life found in ATP, membrane phospholipids, and DNA

Sulfur

A chemical requirement for life used for amino acid

Facultative Halophiles

Can grow in higher than normal salt concentrations, but prefer lower salt levels for optimum growth.

Obligate Halophiles

Archaea that require high/extreme salt conditions, 20-30%, in order to grow.

Plasmolysis

Occurs in a hypertonic solution when the cell membrane pulls away and separates from the cell wall.

Buffer

A substance that resists changes in pH.

Acidophile

An organism that requires extremely low pH conditions to grow.

Psychrotroph

Cold tolerating organisms that grow best at 25 degrees Celsius. Microbes in this category tend to be responsible for most refrigerator spoilage.

Psychrophiles

Cold loving organisms that grow best at 15 degrees Celsius.

Mesophiles

Organisms that grow best between 25 and 40 degrees Celsius. Microbes in this category are typically normal flora or human pathogens.

Minimum Growth Temp

The lowest temperature a microbe will grow in

Maximum Growth Temp

The maximum temperature a microbe will grow in

Optimum Temp

The temperature a microbe will grow the best fastest in.

Physical Growth Requirements

The environment and/or surroundings a microbe needs to grow.

Chemical Growth Requirements

The nutrients a microbe needs to take in to grow.

Thioglycolate Broth

A reducing media that drives off excess oxygen and indicates oxygens presence so anaerobic organisms can grow.

Thermophile

a bacterium or other microorganism that grows best at higher than normal temperatures.

Hyperthermophile

Archaea bacteria that grow at extremely high temperatures and use unusual materials such as sulfur.