Antimicrobial Drugs

These flashcards cover key concepts, definitions, and significant historical events related to antimicrobial drugs as presented in the lecture notes.

What is chemotherapy in the context of antimicrobial drugs?

The use of drugs to treat a disease.

What are antimicrobial drugs?

Substances that interfere with the growth of microbes within a host.

What is an antibiotic?

A substance produced by a microbe that, in small amounts, inhibits another microbe.

What does selective toxicity refer to?

A drug that kills harmful microbes without damaging the host.

Who discovered penicillin, and when?

Fleming discovered penicillin in 1928.

What was the significance of the clinical trials performed by Howard Florey and Ernst Chain in 1940?

They conducted the first clinical trials of penicillin.

What type of bacteria does bacitracin target?

It is a narrow spectrum antibiotic against Gram-positive bacteria.

What is the classification of antibiotics based on their spectrum of activity?

Broad-spectrum antibiotics affect a wide range of bacteria.

What are bactericidal antibiotics?

Antibiotics that kill microbes directly.

What role does chloramphenicol play in antibiotics?

It binds to the 50S subunit and inhibits peptide bond formation.

What is a polyene antifungal drug mentioned in the notes?

Amphotericin B.

What is the mechanism of action for sulfonamides?

They inhibit folic acid synthesis, which is needed for nucleotide synthesis.

What is the minimal inhibitory concentration (MIC)?

The lowest antibiotic concentration that prevents visible bacterial growth.

What does synergism between two drugs mean?

The combined effect of two drugs is greater than the effect of either alone.

What is the potential issue with antibiotic misuse?

It can select for resistance mutants.

What are aminoglycosides?

A class of broad-spectrum antibiotics that change the shape of the 30S subunit.

What unique action does the drug isoniazid have?

It inhibits mycolic acid synthesis.

What do antiviral drugs like acyclovir resemble in structure?

They resemble guanine-containing nucleosides.

What is the mode of action for the drug rifampin?

It inhibits mRNA synthesis.

What can cause a superinfection during antibiotic treatment?

The death of competing bacteria allows members of normal flora to overgrow.

What do resistance genes often rely on for transfer between bacteria?

They are often on plasmids or transposons.

What is the primary purpose of the Disk-Diffusion Test?

To determine the susceptibility of bacteria to antibiotics.