What quality control organism would test Staphylococcus aureus negative for motility testing? What test methodology determines Nitrate Reduction whether an organism can reduce nitrite? True or True Microorganisms capable of reducing nitrite to nitrogen will not turn a color and will produce gas in the nitrate reduction (nitrate to nitrite) test. What are the limitations of nitrate Zinc dust is added if broth does not reduction? become red or no gas is observed. What quality control organism would test Proteus mirabilis (colorless, gas) positive for nitrate reduction? What quality control organism would test Acinetobacter baumanii (red, no gas) negative for nitrate reduction? True or False: True In order to determine optochin susceptibility, a Taxo P disk is placed on an inoculated blood agar plate, incubated, and observed for zone of inhibition. For optochin susceptibility, what size of any zone mm ≥14 the zone of inhibition is considered susceptible (sensitive)? What are limitations of optochin Any zone less than 14 mm is susceptibility? questionable. What quality control organism would test Streptococcus pneumoniae positive for optochin susceptibility? (susceptible) What quality control organism would test S. pyogenes (resistant) negative for optochin susceptibility? What test methodology determines the Oxidase Test presence of cytochrome oxidase activity for oxidase-negative enteric bacteria from other gram-negative rods? The oxidase test determines the presence purple of cytochrome oxidase using dihydrochloride to indophenol, resulting in what color end product? What are the limitations of the oxidase Nickel-base alloy wires that contain test? chromium and iron may cause a false-positive result. What quality control organism test Pseudomonas aeruginosa positive for oxidase test? What quality control organism would test Escherichia coli negative for oxidase test?
What quality control organism would test negative for motility testing? Staphylococcus aureus What test methodology determines whether an organism can reduce nitrite? Nitrate Reduction True or Microorganisms capable of reducing nitrite to nitrogen will not turn a color and will produce gas in the nitrate reduction (nitrate to nitrite) test. True What are the limitations of nitrate reduction? Zinc dust is added if broth does not become red or no gas is observed. What quality control organism would test positive for nitrate reduction? Proteus mirabilis (colorless, gas) What quality control organism would test negative for nitrate reduction? Acinetobacter baumanii (red, no gas) True or False: In order to determine optochin susceptibility, a Taxo P disk is placed on an inoculated blood agar plate, incubated, and observed for zone of inhibition. True For optochin susceptibility, what size of the zone of inhibition is considered susceptible (sensitive)? any zone ≥14 mm What are limitations of optochin susceptibility? Any zone less than 14 mm is questionable. What quality control organism would test positive for optochin susceptibility? Streptococcus pneumoniae (susceptible) What quality control organism would test negative for optochin susceptibility? S. pyogenes (resistant) What test methodology determines the presence of cytochrome oxidase activity for oxidase-negative enteric bacteria from other gram-negative rods? Oxidase Test The oxidase test determines the presence of cytochrome oxidase using dihydrochloride to indophenol, resulting in what color end product? purple What are the limitations of the oxidase test? Nickel-base alloy wires that contain chromium and iron may cause a false-positive result. What quality control organism test positive for oxidase test? Pseudomonas aeruginosa What quality control organism would test negative for oxidase test? Escherichia coli