The Kirby-Bauer Test

Since bacterium vary in size, structure, shape, and susceptibility to antibiotics, antimicrobial chemicals protest in their forte and spectrum of activity. Scientists and doctors need a look to in effect identify types of pathogens in patients, so they could administer a do drugs that would specifically target the organisms. Kirby-Bauer test, in addition know as the disk-diffusion method, is the or so widely used way of testing antimicrobial substances. The effectiveness of a certain chem differentapeutical element is determined by the size of a geographical order of prohibition era on an inoculated nutrient agar plate. A zone of inhibition is the argona where a get across paper disk wet with an antimicrobial agent dictated on the agar uprise inhibits growth of inoculated microorganisms. Based on the size of a zone of inhibition and the relation to a specific chemotherapeutic agent used, organisms are classified as sensitive, intermediate, or resistant. We will name o ut which chemotherapeutic agents are most effective against which organisms. My sign hypothesis was that gibibyte-positive bacteria such as staph aureus would be susceptible to many an(prenominal) chemical agents used in the lab, since they lack an outer tissue point that protects the peptidoglycan mobile phone wall. Whereas gram-negative bacteria such as Escherichia coli or Pseudomonas aeruginosa would be more than resistant than gram-positive bacteria because they have an outer cellphone membrane. However, I also hypothesized that polymyxin B might not be as effective to gram positive S.aureus as other chemical agents, because since this agent was typically to bind to Lipid A in the outer cell membrane of gram-negative bacteria, polymyxin B would not be up to(p) to penetrate the thick peptidoglycan layer of S. aureus. Also, we will be competent to infer the gram defacement of my conclaves unknown organism base on the relationship amidst its sensitivity to other known organisms sensitivities to different antimicrobial agents.\nOur group obtained four small...