Exam 3 (Ch. 10, 13, & 14) - Mja

Question 1

Where did the antibiotics Penicillin originate from?

Answer 1

a mold

Question 2

Who discovered the first anti-microbial drug?

Answer 2

Paul Ehrlich and Sahachiro Hato
-Salvarsan, an aresenic compound to treat syphilis, which was a big problem in the early 1900s

Question 3

What is Therapeutic index

Answer 3

the range of therapeutic dose to toxic dose.
(a high TI because it has a larger wiggle room for dosage)

Question 4

What are sulfa drugs?

Answer 4

-1932 in Germany, the red dye prontosil was found to inhibit growth of S. aureus in animals.
-didn’t work on cultures
-sulfanilamide is the breakdown product and is the active form

Question 5

what anti-bacterial enzyme did Alexander Fleming discover in tears and saliva?

Answer 5

Lysozyme

Question 6

Why would bacteria make antibiotics?

Answer 6

They use it as a defensive mechanism to compete with other bacteria to prevent growth of them.

Question 7

What specific antibiotics inhibit cell wall synthesis?

Answer 7

Penicillin, cephalosporin, vancomycin

Question 8

What specific antibiotic disrupts cell membrane function?

Answer 8

polymyxin

Question 9

What specific antibiotic inhibits translation?

Answer 9

tetracycline, erythromycin, streptomycin, chloramphenicol.

Question 10

What specific antibiotic inhibits metabolism?

Answer 10

sulfonilamide

Question 11

what specific antibiotic inhibits transcription?

Answer 11

rifamycin

Question 12

What specific antibiotic inhibits DNA replication?

Answer 12

quinolones

Question 13

What do B-lactam drug do?

Answer 13

they are bactericidal against a variety of bacteria; inhibit penicillin-binding proteins. Resistance is due to synthesis of B-lactamases, decreased affinity of penicillin-binding proteins, or decreased uptake.

Question 14

what are the characteristics of natural penicillin?

Answer 14

They are active against Gram-positive and a few gram-negative bacteria.

Question 15

What are the characteristics of penicillinase-resistant?

Answer 15

They are similar to natural penicillin, but resistant to inactivation by the penicillinase of staphylococcus.

Question 16

What are the characteristics broad-spectrum penicillin?

Answer 16

They are more active against gram-negative organisms

Question 17

What are the characteristics of extended-spectrum?

Answer 17

They have increased activity against gram-negative rods, including pseudomonas species.

Question 18

What mechanism do B-lactam drugs do to interfere with the bacteria?

Answer 18

Interfere with the formation of the peptide side chains between adjacent strands of peptidoglycan by inhibiting penicillin-binding proteins.

Question 19

What mechanisms do vancomycin do to bacteria?

Answer 19

vancomycin binds to the amino acid side chains of NAM molecules interfering with peptidoglycan synthesis.

Question 20

list three ways antibiotics affect ribosomes:

Answer 20

a.) some aminoglycosides (streptomycin) cause change in the 30S shape, so mRNA is misread
b.) tetracyclines and some aminoglycosides block docking site of tRNA
c.) chloramphenicol blocks peptide bond formation
d.) lincosamides or macrolides bind to 50S subunits, blocking proper mRNA movement through ribosomes. Synthesis stops.
e.) antisense nucleic acid (double stranded RNA)
f.) blocks binding site of ribsomes binding together.

Question 21

What specific action does sulfa drugs do on amino acid synthesis?

Answer 21

sulfa drugs block the enzyme the transition of precursor #1 and precursor #2

Question 22

What specific action does trimethoprim do to block production of amino acids?

Answer 22

Trimethoprim blocks the transition of Dihydrofolate to tetrahydrofolate.

Question 23

What are the considerations when prescribing an antibiotic?

Answer 23

-spectrum of action (is broad-spectrum always better?)
-effectiveness

Question 24

What are the routes of Administration?

Answer 24

Topical, oral, Intramuscular, IV.

Question 25

When do we use the most unnecessary antibiotics?

Answer 25

Ear infections

Question 26

what are mechanisms of antibiotic resistance?

Answer 26

-Production of enzymes that inactivate the drug (B-lactamase)
-altered porins (chromosomal mutation)
-altered target molecules (chromosomal)
-changing metabolic activity-producing more of an enzyme or not using a pathway (chromosomal)
-efflux pumps (R plasmids)
-biofilms-slower MR and diffusion of drug
-producing a protein that protects DNA from the drug (M tuberculosis a protein to protect DNA gyrase from fluoroquinolones.

Question 27

What are ways to prevent development of resistance?

Answer 27

1.) Maintain high enough concentration of drug for sufficient time in patient.
2.) Drug cocktails-different targets OR synergism
3.) Don’t use antibiotics for non-bacterial infections
4.) Limit use of certain antibiotics to “save” them for MDR strains.

Question 28

what are the five core actions from CDC reports.

Answer 28

Prevent infection and prevent spread of resistance. Tracking resistant bacteria. Improving the use of today’s antibiotics. Ivest in development of vaccines, therapeutics, and diagnostics. Improve sanitation and access to safe water (keep antibiotics out of environment)

Question 29

Explain some characteristics of anti-viral drugs.

Answer 29

More difficult to achieve selective toxicity. More difficult to test. many are specific for certain viruses, but often difficult to test for the infecting virus.

Question 30

What are the covid drugs and what are the mechanisms of them?

Answer 30

Remdesivir-RNA-dependent RNA polymerase inhibitor.
Paxlovid-Nirmatrelvir (protease inhibitor) + ritonavir (cytochrome P450 inhibitor)
Molnupiravir-RNA nucleoside that causes mutations in RNA viruses

Question 31

What bacterial cell structures would you target for ABX development?

Answer 31

ETC, well wall, ribosome, cell membrane

Question 32

what does Beta lactamase do?

Answer 32

Beta lactamase is secreted from the bacterial cell cleaves the antibiotic molecule and renders it in active

Question 33

what are 3 mechanisms of resistance

Answer 33

1.) Mutation can alter the receptor that transports the drug, so that the drug cannot enter the cell
2.) Some drugs block the usual metabolic pathways, the cell can use an alternative pathway
3.) The cell can create a pump that pumps the drug out of the cell

Question 34

What is the infectious process?

Answer 34

Attachment, Penetration, Uncoating, Biosynthesis, Maturation, Release

Question 35

What are three ways animal viruses enter the cell?

Answer 35

1.) Direct Penetration
2.) Membrane Fusion
3.) Endocytosis

Question 36

Name three DNA viruses and three RNA viruses.

Answer 36

Herpes, pox, parvo = DNA
corona, retro, arena = RNA

Question 37

How do DNA viruses and retroviruses get their genome to the nucleus

Answer 37

This happens during mitosis when host DNA replicates and nuclear membrane dissolves

Question 38

Tell me about antibiotic threats CDC reports

Answer 38

2.8 million people get antibiotic infections each year. Chlostridiodes difficile infections caused by antibiotics are very popular (223,900 hospitalized

Question 39

What are the top 5 biggest antibiotic resistance threats?

Answer 39

Carbapenem-resistant Acinetobacter, Candida auris, carbapenem-resistant Enterbacteriaceae, C-diff, Drug-resistant Neisseria gonorrhea