Bac metabolism Lec 4. 3

Question 1

thioglycollate

Answer 1

A reducing agent that can be added to a medium to test an organism’s requirement for oxygen

Question 2

in regards to oxygen, Streptococcus mutans is?

Answer 2

an aerotolerant anaerobe

Question 3

in regards to oxygen, Porphyromonas gingivalis is?

Answer 3

an obligate anaerobe

Question 4

Several toxic forms of oxygen can be formed in the cell, but _____ are present that can neutralize most of them

Answer 4

enzymes

Question 5

what seems to be the most common toxic oxygen species?

Answer 5

superoxide

Question 6

What are 4 enzymes that neutralize reactive oxygen molecuels?

Answer 6

superoxide dismutase
Catalase
Peroxidase
Superoxide reductase

Question 7

superoxide dismutase

Answer 7

converts superoxides to hydrogen peroxides

Question 8

Catalase

Answer 8

converts hydrogen peroxide to water and oxygen

Question 9

Peroxidase

Answer 9

converts hydrogen peroxide to water

Question 10

Superoxide reductase

Answer 10

converts superoxides to hydrogen peroxides

Question 11

Catalase test is used to? Explain

Answer 11

differentiate between Streptococcus isolates and Staphylococcus isolates
*add bacteria to drop of H2O2
H2O2 + H2O2 Catalase 2H2O + O2
(Bubbles)

Question 12

cardinal temperatures

Answer 12

are the minimum, optimum, and maximum temperatures at which each organism grows

Question 13

what happens are minimum cardinal temperature? maximum?

Answer 13

• minimum- membrane gelling; transportprocesses so slow that growth cannot occur
• maximum- protein denaturation; collapse of the cytoplasmic membrane and thermal lysis

Question 14

Superoxides O2, hydrogen peroxide H2O2, and hydroxyl radicals OH are examples of?

Answer 14

Reactive Oxygen molecules

Question 15

Microbes differ in the temperature ranges they will tolerate. What are the 5 groups?

Answer 15

1) psychrophile
2) meseophil
3) thermophile
4) hyperthermophile
5) extreme hyperthermophile

Question 16

psychrophile temp range?

Answer 16

<0oC to12oC

*Polaromonas vacuolata

Question 17

meseophil temp range?

Answer 17

<10oC to around 50oC

*Escherichia coli

Question 18

thermophile temp range?

Answer 18

40oC to around 70oC

*Geobacillus stearothermophilus

Question 19

hyperthermophile temp range?

Answer 19

65oC to close to 100oC

*Thermococcus celer

Question 20

extreme hyperthermophile temp range?

Answer 20

90oC to>110oC

*Pyrolobus fumarii

Question 21

Hyperthermophiles inhabit what two extremem locations?

Answer 21

hot environments up to and including boiling hot springs, as well as undersea hydrothermal vents that can have temperatures in excess of 100ºC

Question 22

psychrophile example?

Answer 22

Polaromonas vacuolata

Question 23

meseophil example?

Answer 23

Escherichia coli

Question 24

thermophile example?

Answer 24

Geobacillus stearothermophilus

Question 25

hyperthermophile example?

Answer 25

Thermococcus celer

Question 26

extreme hyperthermophile example?

Answer 26

Pyrolobus fumarii