Oxygen usage and toleranve patterns in microbes

Question 1

Can use gaseous oxygen in their metabolism and possess the enzymes need to process toxic oygenic products.

Answer 1

Aerobes
ex. most fungi, protozoa and many bactria

Question 2

These do not grow at normal atmospheric concentrations of oxygen but require a small amount of it in metabolism

Answer 2

microaerophiles
(organisms that live in soil or water or in a mammalian host)

Question 3

Facultative anaerobes

Answer 3

do not require oxygen but use it when it is present
-can perform anaerobic metabolism
ex. gram negative intestinl\al bacteria, staphylocci

Question 4

Anaerobes

Answer 4

lack metabolic enzyme for oxygen in respiration,
ex. oral bacteria & intestinal bactera

Question 5

aerotolerant anaerobes

Answer 5

• do not utilize oxygen but can survive and grow to a limited extent in it presecnce

Question 6

Microrganisms of carbon dioxide

Answer 6

Capnophiles: organisms that grow best at a higher CO2 tension than is normally present in the atmosphere

ex. Neisseria (gonorrhea, meningitis), Brucella (undulant fever), Streptococcus pneumoniae

Question 7

Defined as the degree of acidity or alkalinity of a solution:

Answer 7

pH = 7; pure water
pH = 1-6; acidity increases
pH = 8-14; the alkalinity increases
The majority of organisms live or grow in habitats between pH

Question 8

organisms that thrive in acidic environments
Euglena mutabilis: grows in acid pools between pH 0 and 1
Thermoplasma: lives in coal piles at a pH of 1 or 2
Picrophilus: thrives at a pH of 7, but can live at a pH of 0
Many molds and yeasts tolerate acid and are the primary spoilage agents of pickled foods

Answer 8

Acidophiles

Question 9

organisms that thrive in alkaline conditions

Answer 9

Alkalinophiles:

Question 10

types of Alkalinophiles:

Answer 10

Natromonas: live in hot pools and soils at pH 12
Proteus: can create alkaline conditions to neutralize urine and colonize and infect the urinary system

Question 11

live in habitats with high solute concentration

Answer 11

osmophiles

Question 12

prefer high salt concentration

Answer 12

halophiles