Antimicrobial Chemotherapy and Laboratory Testing

Flashcards covering the mechanisms of antibiotics, bacterial cell targets, laboratory testing methods like disc diffusion, and clinical measurements of antibiotic efficacy.

Antimicrobial chemotherapy

Using drugs to kill bacteria or stop them growing inside the human body.

Cell wall

A structure present in bacterial cells but absent in human cells, targeted by antibiotics like Penicillin to make bacteria burst and die.

70S ribosomes

Specific protein-making structures found in bacterial cells that antibiotics target to block protein synthesis.

Penicillin

An example of an antibiotic that stops the bacterial cell wall from forming.

Protein synthesis inhibition

A mechanism where antibiotics like Tetracycline or Streptomycin block bacterial ribosomes, preventing the bacteria from living or dividing.

DNA replication and transcription inhibition

A mechanism where antibiotics like Ciprofloxacin or Rifampicin block the bacterial ability to copy DNA, preventing reproduction.

Tetracycline

An antibiotic that blocks bacterial ribosomes to inhibit protein synthesis.

Streptomycin

An antibiotic that blocks bacterial ribosomes to inhibit protein synthesis.

Ciprofloxacin

An antibiotic that blocks DNA replication and transcription inside bacteria.

Rifampicin

An antibiotic that blocks DNA replication and transcription inside bacteria.

Disc diffusion (Dunker test)

A laboratory procedure where paper discs soaked with antibiotics are placed on an agar plate to determine which drug works against a specific bacterium.

Agar

A jelly-like substance used in the laboratory as food for bacteria to grow on plates.

Bacterial lawn

A layer formed when a patient's bacteria are spread all over an agar plate for testing.

Zone of inhibition

A clear circle appearing around an antibiotic disc on an agar plate indicating that the antibiotic is effective at stopping bacterial growth.

Resistant bacteria

Bacteria that grow right up to an antibiotic disc in a lab test, indicating the drug does not work against them.

Incubation temperature

The laboratory temperature used to grow bacteria on agar plates, which is $37\,\text{°C}$.

MIC (Minimum Inhibitory Concentration)

The lowest amount of antibiotic needed to stop bacterial growth in a laboratory setting.

MBC (Minimum Bactericidal Concentration)

The lowest amount of an antibiotic that actually kills the bacteria.

Bactericidal

A type of antibiotic that kills bacteria directly; useful when the patient's immune system is weak.

Bacteriostatic

A type of antibiotic that stops bacterial growth so that the human immune system can clear the infection.