Lecture Notes on the Staphylococci

The Staphylococci are gram (+) cocci which appear to be arranged in clusters. These organisms are salt tolerant and catalase positive.

Three species are important in humans as part of the normal flora and as pathogens.:


Questions for Thought..........

  1. Why is Mannitol Salt Agar considered to be both a selective and a differential medium?
  2. What is the biochemistry of the color change that occurs with Staphylococcus aureus on MSA?
  3. What does the coagulase test measure?
  4. How might coagulase be important to Staphylococcus aureus?
  5. What is serum? What is plasma? Which is used in the coagulase test?