Microbiology Lab 6 Flashcards
Grow optimally above 45 degrees C and some can grow at near boiling temperatures
Thermophiles
Grow optimally below 20 degrees C and some will grow well at subzero temperatures
Psychrophiles
Grow best between 20-45 degrees C
Mesophiles
Many bacteria can tolerate and even grow at temperatures much lower than their optimum temperature. (Ex: some will optimally grow at 35 degrees C but can grow down to zero)
Psychroduric Mesophile
Microbes which grow only in the presence of oxygen
Obligate Aerobes
Do not grow in the presence of oxygen
Obligate Anaerobes
Are able to grow in the presence or absence of oxygen (because they adjust their metabolism to oxygen: in oxygen they are respiratory while in anaerobic conditions they ferment)
Facultative Anaerobes
Microbes that can tolerate oxygen but do not utilize it, instead they ferment both anaerobic ally and aerobically
Aerotolerant Fermenter
When reduced turns colorless; when oxidized turns red
Resazurin
When reduced turns colorless; when oxidized turns blue
Methylene Blue
Oxygen requiring aerobes that can not tolerate high concentrations of oxygen (they lack important enzymes that protect from the toxic effects of oxygen)
Microaerophiles
An iron containing protein that avidly binds first a molecule of hydrogen peroxide and then when it comes upon the next hydrogen peroxide it reacts the first with the other to form oxygen and water thereby eliminating hydrogen peroxide
Catalase (Catalase Test)
The generation of bubbles within a minute is a positive test for this type of test
Catalase Test
Tests for the presence of cytochrome c (if a microbe has cytochrome c it will be able to oxidize the test reagent [tetramethyl-paraphenylenediamine] which is colorless to a blue color)
Oxidase Test
The change in the color of the bacteria to dark blue within a few seconds is a positive test for this test
Oxidase Test
