The known organism used in the CAMP test is Streptococcus agalactiae (group B streptococci).
The CAMP test is a diagnostic microbiological procedure used to identify Streptococcus agalactiae. It relies on the synergistic hemolytic activity between the CAMP factor produced by S. agalactiae and the beta-lysin produced by Staphylococcus aureus.
How the CAMP Test Works:
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Staphylococcus aureus is streaked: A strain of Staphylococcus aureus that produces beta-lysin (also known as beta-hemolysin) is streaked down the center of a blood agar plate.
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Streptococcus agalactiae is streaked: The suspected Streptococcus agalactiae isolate is then streaked perpendicularly to the Staphylococcus aureus streak, without touching it.
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Incubation: The plate is incubated at 35-37°C in ambient air or CO2 enriched environment for 18-24 hours.
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Observation: The plate is then examined for enhanced hemolysis (enlarged area of clearing) in the zone where the two streaks meet.
Interpreting the Results:
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Positive CAMP test: A positive result is indicated by a characteristic arrowhead-shaped zone of enhanced hemolysis at the intersection of the two streaks. This indicates that the organism produces CAMP factor and is likely Streptococcus agalactiae.
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Negative CAMP test: A negative result shows no enhanced hemolysis at the intersection of the streaks, suggesting the organism is not Streptococcus agalactiae.
In essence, Streptococcus agalactiae produces the CAMP factor, which enhances the beta-hemolysis produced by Staphylococcus aureus, leading to a distinct and easily observable result.
