Microbiology exam essays BY 221 Microbiology 215 exam #2 chap 7, 11, 12 81-90 essay: 10 points Describe the Kirby Bauer Test? Make sure you describe all the key elements. 1. Using sterile technique, inoculate 3 nutrient agar plates individually with: a. E. coli b. S. aureus c. M. smegmatis 2. Place antibiotic disks evenly spaced on the inoculated agar plates and incubate at 370C for 24-48 hours. 3. Using sterile technique, inoculate 3 nutrient agar plates individually with: a. E. coli 4. Using sterile technique place disk in each of the solutions: a. % ethyl alcohol b. Formaldehyde (Formalin) c. Iodine d. 3% hydrogen peroxide Then place each disk evenly spaced on a labeled nutrient agar plate for each bacterial species (3) and incubate for 24-48 hours at 370C. *This information was taken from our lab books so the credit reference goes to the micro lab book. * Why is this test not applicable to all bacteria types? The KB Test is not applicable on all bacteria types because some bacteria will not grow on solid media or it will Just grow too slowly in relation to the diffusion.
This will ause the antibiotic to reach the edge of the dish before any zone of growth can be reviewed. For some bacteria, the size of the zone of inhibition has not been correlated with therapeutic outcome. “Kirby-Bauer Test for Bacterial Resistance to Particular Antibiotics. ” Kirby-Bauer Test for Bacterial Resistance to Particular Antibiotics. N. p. , n. d. Web. < http://facweb. northseattle. edu/estavney/Bi0260/Lab %20Handouts/8%20KirbyBauerEval. doc>. What alternatives are there to the Kirby Bauer Test? Stokes Method is an alternative to the KB Test.
Lalitha, M. K. , Dr. “Manual on Antimicrobial Susceptibility Testing ” . Manual on Antimicrobial Susceptibility Testing. N. p. , 21 Sept. 2004. Web.. 91-100 essay: 10 points Describe 3 mechanisms of antimicrobial resistance: The three mechanisms of antimicrobial resistance are: inactivation or modification of the antibiotic, alteration in the target site of the antibiotic that reduces its binding capacity and reduced intracellular antibiotic accumulation by decreasing permeability or increasing active efflux of the antibiotic.
Pendland, Susan L. , Pharm. D. “BACTERIAL RESISTANCE. ” BACTERIAL RESISTANCE. N. p. , n. d. web.. Why is the possibility of a plasmid transferring information to another bacteria so important in controlling the spread of resistance? E. g. NDM-I or E. coli spreading in Europe. It helps to make cells resistant and helps make tons of proteins. This can help so antibiotics will target Just the bacteria and not the entire. “Plasmid. ” Plasmid. N. p. , n. d. Web.. 101-110 Bonus: Why are spore strips used to monitor proper autoclaving?
A spore strip is preloaded with a fairly innocuous, but hard-to-kill spore. If your autoclave didn’t kill all those spores, you’ll be able to grow a culture from the spore strip. If nothing grows, your auto-clave did the Job properly. Nyberg, Russ. “Autoclave/Dry Heat Monitoring. ” Autoclave/Dry Heat Monitoring. N. p. , n. d. Web.. Which disinfectant(s) would you use to clean a room contaminated with Clostridium difficile? The most recommended method for sterilization is soap and water since Clostridium difficile cannot be killed with an alcohol based disinfectant.
To sterilize and entire room or area, they recommend using bleach. “Healthcare-associated Infections (HAIs). ” Frequently Asked Questions about Clostridium Difficile for Healthcare Providers. N. p. , 25 Nov. 2010. Web.. Why? Clostridium difficile cannot be killed with alcohol based disinfectants which is why soap/water or bleach are the chosen solutions. “Healthcare-associated Infections (HAIs). ” Frequently Asked Questions about Clostridium Difficile for Healthcare providers. N. p. , 25 NOV. 2010. web..