MB lectures 7-8

What is the temperature, pH, and salt concentration that is considered normal growth conditions?

20-40 deg Celsius, pH 7, and 0.9% salt concentration

What is an extremophile?

Any organism that can grow outside “normal“ growth conditions

Name 5 environmental limits on microbial growth.

Temperature, pH, osmolarity, oxygen, pressure

What temperature range can psychrophiles grow in?

0-20 deg Celsius

What temperature range can mesophiles grow in?

15-45 deg celsius

What temperature range can thermophiles grow in?

40-80 deg celsius

What temperature range can hyperthermophiles grow in?

65-121 deg celsius

What are barophiles?

Organisms adapted to high pressures

What are barotolerant organisms?

Organisms that grow at high, but not very high pressures

What are barosensitive organisms?

Organisms that die at high pressure(most bacterial, all mammals)

What is osmolarity?

Number of solutes in solution

What effect does low osmotic pressure outside the cell have?

Water enters the cell, can cause cell to leak or burst.

What effect does high osmotic pressure outside the cell have?

Water leaves the cell, cell shrinks

What are halophiles?

Organisms that require a high concentration of NaCl

What are neutralophiles and where can they grow?

Organisms that grow at pH 5-8. Can grow in gut

What are acidophiles and where can they grow?

Organisms that grow at pH 0-5. Can grow in stomach acid, sulfuric acid springs

What are alkalophiles and where can they grow?

Organisms that grow at pH 9-11. Grows in soda lakes

What are aerotolerant anaerobes?

Can grow in O2 , but can not utilize it

What are obligate anaerobes?

Cannot grow in environments with O2

What are micro-aerophiles?

Grow only at low O2 levels (< 10%)

What are Facultative Aerobes?

Can grow aerobically or anaerobically, although aerobic growth is more energy-efficient

In this figure, label what type of bacteria are growing in each tube.

What is sterilization and what mechanisms can be used to do it?

The destruction or removal of all viable organisms from inanimate objects ̈ Can use autoclave or high energy ionizing radiation

What is disinfection and what mechanisms can be used to do it?

The killing, inhibition, or removal of vegetative microorganisms from inanimate objects (not endospores)

Can use phenolics, boiling water, UV radiation

What is antisepsis and what mechanisms can be used to do it?

Chemicals applied to body surfaces (living tissue) to prevent infection of living tissue by microorganisms

Can use Iodine, ethanol

What is chemotherapy and what mechanisms can be used to do it?

Use chemicals to internally kill or inhibit microbial growth within host tissues EX: antibiotics

Rank the pasteurization methods from least to most sterilizing.

Pasteurization, flash pasteurization, UHT

What type of pasteurization kills all cells and creates products that can be kept outside of the fridge?

UHT- ultra high temperature(150 deg C for 3 sec)

What does an autoclave do?

Holds contents at high temperature and high pressure. Kills all bacteria, even endospores

What is a laminar flow biological safety cabinet?

Forces air through HEPA filter, which removes over 99.9% airborne particulate material 0.3 μm or larger to protect researchers working on pathogenic material

Disinfectants kill _______(all/some) microbes and _______(damages/has no effect on) eukaryotic cells.

all; damages

Chlorine, iodine, soap, and detergents are all examples of:

disinfectants

Antibiotics kill _______(all/some) microbes and _______(damages/has no effect on) eukaryotic cells.

some; has no effect on

What is catabolism?

Breaking down molecules for energy

What is anabolism?

Using energy to build cell components

What are energy carriers?

Molecules that gain and release energy.

Storing energy from energy-yielding reactions, providing energy to energy-requiring reactions

How does oxidative phosphorylation differ for substrate level phosphorylation?

Substrate level is the direct transfer of phosphate to ADP.

Oxidative produces large amounts of ATP using proton motive force and ATP synthase.

How are electrons transported using the electron transport system?

Through electron carriers

Protons are pumped into the ___________ space, where they travel back ________ via ATP synthase.

periplasmic space; inside the cell

a collection of membrane proteins that converts the energy of redox reactions into a proton potential

Electron transport chain