Chapter 14: Controlling Microbes in the Body

Waksman

Antibiotics from Streptomyces

Fleming

Discovered penicillin

Domagk

Discovered sulfanilamide

Ehrlich

Used arsenic compounds as “magic bullets”

Compare natural, semisynthetic, and synthetic antibiotics

Natural: Soil, bacteria

Semisynthetic: Natural but modified (chemical)

Synthetic: Made from chemical

Explain selective toxicity. Why are there more antibiotics effective in killing bacteria than eukaryotic pathogens and viruses?

More targets for bacteria because they are Prokaryotic organisms; Eukaryotic pathogens share many metabolic enzymes and cell structures with humans; virus are more simple particles and don’t have many targets

Describe 6 mechanisms of action for antibiotics and majorr drugs in the category

-Inhibit protein synthesis:

-Inhibit metabolic pathways:

-Inhibits DNA function/synthesis:

-Inhibit cell wall synthesis:

-Inhibit membrane synthesis, components

Never

Let

Monkeys

Eat

Bananas

Neutrophils (60-70%)

Lymphocytes (20-40%)

Monocytes (3-10%)

Eosinophils (1-4%)

Basophils (1%)

The ideal antibiotic should be

One that targets specific organism, effective, safe, does not lead resistance

Compare narrow-spectrum to broad-spectrum antibiotics Is there a disadvantage to using a broad-spectrum antibiotic?

-Oral: took antibiotic by mouth and went through the digestive system (takes awhile)

-IM (intramuscular): Had it in the arm and it got absorbed in the muscle then into the bloodway (2nd to fast reaction)

-IV (intravenous): Straight in the vein(fastest process)

3 examples of how the use of antibiotics causes a patient harmful side effect

1. Kill good bacteria (microbiota)

2. Pregnant woman can’t take it

How can microbes become resistant to antibiotics?

-Mutate target enzyme

-Block entrance

-Secretes the antibiotic

-Inactivate the antibiotic

How can we slow down the development of antibiotic resistance? List 5 mechanisms of resistance

Using antibiotics less frequently; use only four bacterial infections