AMR Flashcards
Describe Agar diffusion assay
- Spread plate with lawn of test strain.
- Place antibiotic discs on lawn.
- Incubate overnight.
- Examine plate for zones of inhibition.
What are the two methods for AMR?
Agar diffusion assay and broth dilution assay.
What are antibiotics?
variety of substances derived from microorganisms that control the growth or kill bacteria.
What are synthetic antibiotics?
Chemically related to natural antibiotics, also produced to control the growth of or kill bacteria.
Describe broth dilution assay.
Broth in test tubes with different antibiotic concentrations. Inoculate all tubes with bacteria and incubate overnight = growth. MICR is seen where no bacteria growth. MBC is seen when test tube contents places on petri dish and incubated overnight.
3 types of classes of antibiotics
broad-spectrum, bactericidal/bacteriostatic, against gram+ and gram-.
3 examples of bactericidal antibiotics?
Penicillin G, Ampicillin, Amoxicillin.
What is Penicillin G?
becta-lactam antibiotic, inhibits cell wall synthesis, against Gram+.
2 examples of bacteriostatic?
tetracycline and chloramphenicol.
What does tetracycline do and what bacteria is it against?
Binds to 16s rRNA - inhibits action of prokaryotic 30s ribosome.
Against Gram- and Gram+.
Example of bactericidal/bacteriostatic?
Gentamicin binds to 30s ribosomal subunit. Against mostly Gram-.
How is Ampicillin different to Penicillin G?
By 1 amino group. Better penetration of Gram- cell wall.
What is Amoxicillin against?
Gram+ and some Gram-
What is ampicllin against?
Gram+ and some Gram-
What is Penicillin G against?
Gram+.
