Chap 24 - Antimicrobials

Question 1

Who originated the concept of selective toxicity?

Answer 1

Ehrlich originated the concept of selective toxicity.

Question 2

What is selective toxicity?

Answer 2

The selective toxicity of antibiotics means that they must be highly effective against the microbe but have minimal or no toxicity to humans. “Harm the pathogen / not the host.”

Question 3

Penicillium kills what kind of bacteria

Answer 3

Penicillium mold produces a substance that kills gram-positive bacteria.

Question 4

What kind of “agents” are made in a pharmaceutical lab?

Answer 4

Synthetic Agents

Question 5

These are products of or derived from the metabolism of living microorganisms?

Answer 5

Antibiotics

Question 6

These are a new generation antimicrobials which are chemically modified antibiotics?

Answer 6

Semisynthetic drugs

Question 7

_____is a dose of a drug is the concentration causing harm to the host.

Answer 7

Toxic Dose

Question 8

______is referred to as the concentration eliminating pathogens in the host.

Answer 8

Therapeutic Dose

Question 9

The toxic and therapeutic doses are used to formulate the ________.

Answer 9

Chemotherapeutic Index (Toxic / Therapeutic)

Question 10

Drugs have a range of pathogens on which they will work, this is referred to as the ______.

Answer 10

Antimicrobial spectrum.

Question 11

Synthetic Antibacterial Agents do what?

Answer 11

Inhibit DNA Synthesis and Cell Wall Formation

Question 12

What are characteristics of Sulfanilamides?

Answer 12

1. Target specific metabolic reactions. 2. Out compete essential folic acid components for binding sites in a bacterial enzyme. 3. Prevent nucleic acid synthesis and DNA replication.

Question 13

Sulfanilamides are categorized as what kind of antibacterial agents?

Answer 13

Synthetic Agents

Question 14

What are three common Synthetic Agents?

Answer 14

Sulfanilamides, Isoniazid, Quinolones.

Question 15

Quinolones does what?

Answer 15

Blocks DNA synthesis in bacteria.

Question 16

Isoniazid do what?

Answer 16

Interferes with cell wall synthesis in species of Mycobacterium by inhibiting the production of mycolic acid

Question 17

Beta-Lactam Antibiotics do what?

Answer 17

Beta-Lactam Antibiotics Inhibit Bacterial Cell Wall Synthesis

Question 18

How does Penicillin work?

Answer 18

Active against many gram-positive and some gram-negative bacteria. Interfere with cell wall synthesis in rapidly growing cells, causing the cell to burst.

Question 19

Penicillin-resistant species produce _______ that inactivate penicillin?

Answer 19

Beta-lactamases

Question 20

Name two broad spectrum beta-lactams

Answer 20

Ampicillin and Amoxacillin

Question 21

What are broader spectrum semi-synthetic penicillins alternatives to penicillin?

Answer 21

Cephalosporins

Question 22

What are monobactams active against?

Answer 22

Aerobic, gram-negative rods.

Question 23

What is vancomycin effective against? And what are the side effects?

Answer 23

Gram-positive bacteria such as staphyococci. Side effects include damage to ears and kidneys.

Question 24

Polypeptide antibiotics affect what?

Answer 24

The Cell membrane

Question 25

Name two polypeptide antibiotics

Answer 25

Bacitracin, and Polymyxin

Question 26

Which polypeptide antibiotic is only used topically because it is toxic?

Answer 26

Bacitracin

Question 27

Tetracyclines are broad spectrum antibiotics that | target the attachment of ______.

Answer 27

tRNA to the 30S subunit.

Question 28

What antibiotic causes "Gray baby" syndrome?

Answer 28

Chloramphenicol

Question 29

Chloramphenicol is reserved for serious infections such as _______.

Answer 29

Meningitis, cholera, typhoid and typhus fevers, and rocky mountain spotted fevers.

Question 30

Rifampin inhibits synthesis of what?

Answer 30

Nucleic Acid

Question 31

Rifampin interferes with what?

Answer 31

RNA Synthesis

Question 32

True or False - MRSA is a gram-positive bacteria?

Answer 32

True

Question 33

What semisynthetic drug used against penicillin-resistant bacteria?

Answer 33

Clindamycin

Question 34

List the ways antibiotic resistance can develop.

Answer 34

1. Mutations 2. Horizontal Gene Transfer (T/T/C) 3. Altering metabolic pathways 4. Inactivating antibiotics 5. Reducing membrane permeability 6. modifying the drug targets.

Question 35

A polyene used to treat Candida infections

Answer 35

Nystatin

Question 36

Initial quartet of wonder drugs are:

Answer 36

Penicillin, streptomycin, chloramphenicol, and tetracycline.