Other Exam 1 questions

Question 1

What are the key differences between a human and bacterial cell?

Answer 1

Bacterial cell: have a cell wall, 70S ribosomes, single cellular, 1 circular chromosome, no membrane bound organelles and have plasmids
Human cells: have no cell wall, 80S ribosomes, multicellular, 23 linear chromosomes, membrane bound organelles and no plasmids

Question 2

what are plasmids?

Answer 2

small circular non -chromosomal DNA. these allow for antibiotic resistance mechanisms. exotoxins

Question 3

What is a bacterial capsule?

Answer 3

covering made of sugars/polysaccharides. they prevent phagocytosis and aid in attachment. these can be mimicked to create vaccines.

Question 4

Bactericidal agents?

Answer 4

kill bacteria

Question 5

Bacteriostatic

Answer 5

slow/inhibit bacterial growth

Question 6

What is the role of DNA gyrase/ topoisomerase-IV in bacteria? what happens if we inhibit this process?

Answer 6

DNA Gyrase unwinds supercoiled DNA. Topoisomerase IV can cut DNA to separate paternal strands from daughter strands. They are both involved in DNA replication and inhibits them is lethal. fluroquinolones use this function.

Question 7

Where does folic acid in humans cells come from?

Answer 7

diet-food

Question 8

where do bacteria get folic acid?

Answer 8

they make it as a cofactor to be used in DNA precursor synthesis

Question 9

What 2 enzyme are critical in the synthesis of folic acid in bacterial cells?

Answer 9

Dihydropteroate synthase and dihydrofolate reductase (DHFR)

Question 10

What drug class inhibits dihydropteroate synthase ?

Answer 10

Sulfa drugs

Question 11

What drug inhibits bacterial DHFR?

Answer 11

Trimethoprim

Question 12

Which drugs target the 30S ribosomal unit?

Answer 12

Aminoglycosides!!!!!! and tetracyclines

Question 13

Which drug targets the 50S ribosomal unit?

Answer 13

Macrolides

Question 14

what genes and resistance mechanisms do MRSA vs MSSA have?

Answer 14

MSSA-beta-lactamase
MRSA- mecA gene