Bacterial Growth & Physiology

Question 1

Obligate anaerobes

Answer 1

Obligate anaerobes – can only growth in absence of oxygen

Question 2

Poison

Answer 2

Poison – radicals, superoxide, and H2O2 damage cell, lack antioxidant enzymes

Question 3

Obligate aerobes

Answer 3

Obligate aerobes – can only growth in presence of oxygen, contain all antioxidant enzymes

Question 4

Microaerophiles

Answer 4

Microaerophiles – require low percent oxygen

Question 5

Aerotolerant anaerobes

Answer 5

Aerotolerant anaerobes – do not use oxygen to grow but are not affected

Question 6

Facultative anaerobes

Answer 6

Facultative anaerobes – use oxygen in present (more efficient) but can live without it

Question 7

Respiratory Metabolism

Answer 7

Respiration – more efficient, TCA cycle to produce ATP, NADH, and FADH2 in presence of oxygen

Question 8

Fermentation

Answer 8

Fermentation – glycolysis, pyruvate → ATP in absence of oxygen, recycling of NADH → NAD+

Question 9

Pentose Phosphate

Answer 9

Pentose phosphate – produces reducing power (NADPH), hexose monophosphate shunt

Question 10

Iron utilization:

Answer 10

highly insoluble as Fe3+, bound to proteins

Question 11

Siderophores

Answer 11

– scavenge iron, high affinity

Question 12

Antiseptic

Answer 12

Antiseptic – used on tissue to reduce microbes

Question 13

Aseptic

Answer 13

Aseptic – absence of pathogenic microbes

Question 14

Antibiotic Targets

Answer 14

Targets – cell wall, protein synthesis, RNA/DNA synthesis

Question 15

Disinfectant

Answer 15

Disinfectant – chemical kills microbes on objects, not sterile

Question 16

Sterilization

Answer 16

Sterilization – complete killing of all organisms, autoclave

Question 17

Antibiotic Replication

Answer 17

Replication – DNA polymerase, topoisomerase IV, gyrase (topo II)

Question 18

Antibiotic Transcription

Answer 18

Transcription – RNA polymerase

Question 19

Antibiotic Translation

Answer 19

Translation – 30S and 50S rRNA subunits

Question 20

Biochemical Resistance

Answer 20

Resistance –

Biochemical – enzymatic inactivation of antibiotic, ex: target site change, permeability

Question 21

Genetic resistance

Answer 21

Genetic – chromosomal mutation or genetic exchange

Question 22

Penicillin

Answer 22

Penicillin – inhibits cell wall synthesis by binding to PBP, preventing formation of peptidoglycan

Question 23

Vancomycin

Answer 23

– inhibits cell wall synthesis by binding to D-ala to prevent cross-linking