Ch. 14 controlling microbes in body

Antibiotics from streptomyces

Waksman

Discover penicillin

Fleming

Discovered sulfanilamide

Domagk

Used arsenic compounds as "magic bullets”

Ehrlich

Natural antibiotic

Natural, bacteria, soil

Semisynthetic antibiotic

Antibiotics that have been isolated as natural products and then chemically modified

Synthetic antibiotic

Lab made

Selective toxicity

To kill or inhibit the growth of microbial targets without harming the patient

Why are there more antibiotics effective in killing bacteria than eukaryotic pathogens and viruses?

Bacteria have more unique targets for selective toxicity

6 mechanisms of action for antibiotics and major drugs in the category

Inhibits cell wall ( peptidoglycan )

Inhibits biosynthesis of proteins ( ribosomes )

Disrupt membranes ( plasma membranes )

Inhibit nucleic acid synthesis ( RNA/DNA )

Antimetabolites ( enzymes )

Myocobacterial adenosine triphosphate (ATP) synthase inhibitor (RNA/DNA)

Ideal antibiotic

One that targets specific organisms, effective, safe, and doesn’t lead to resistance

Narrow-spectrum

Target’s specific set of bacteria ( G+, G- )

Broad - spectrum

Targets a wide variety of bacteria

Is there a disadvantage using a broad-spectrum antibiotic?

Can lead to super infection

Positive/negative attributes of tropical antibiotics

Only on surface

Allergenic reaction

Positive/negative attributes of oral antibiotics

Conveniently taken at home

Slowest

Positive/negative attributes of intramuscular antibiotics

Second fastest

Positive/negative attributes of intravenous antibiotics

Fastes

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

Kills good bacteria ( microbiota )

Causes teeth to turn brown

Could cause secondary opportunistic infection

5 mechanisms of resistance

Mutate target enzyme

Block entrance

Secrete antibiotic

Inactivate antibiotic

How can we slow down the development of antibiotic resistance?

Using antibiotics less frequently, use only for bacterial infection