Which of the following is a major virulence factor of Cryptococcus species?a.Haemolysinb.Collagenasec.Fimbriaed.Capsule

To determine the major virulence factor of Cryptococcus species, we need to analyze the given options: haemolysin, collagenase, fimbriae, and capsule.

Step 1: Understand the question and options Cryptococcus species are known to cause infections, so we are looking for the factor that contributes to their virulence. The options are haemolysin, collagenase, fimbriae, and capsule.

Step 2: Analyze each option a. Haemolysin: Haemolysin is a protein that can cause the lysis of red blood cells. While it can contribute to virulence in some bacteria, it is not a major virulence factor in Cryptococcus species.

b. Collagenase: Collagenase is an enzyme that breaks down collagen, a major component of connective tissue. While it can be important in tissue invasion by some bacteria, it is not a major virulence factor in Cryptococcus species.

c. Fimbriae: Fimbriae are hair-like structures on the surface of bacteria that can aid in attachment to host cells. While fimbriae can contribute to virulence in some bacteria, they are not a major virulence factor in Cryptococcus species.

d. Capsule: The capsule is a major virulence factor in Cryptococcus species. It is a thick polysaccharide layer that surrounds the fungal cell and helps protect it from the host immune system. The capsule allows Cryptococcus species to evade phagocytosis and establish infection, making it a major virulence factor.

Step 3: Determine the correct answer Based on the analysis, the major virulence factor of Cryptococcus species is the capsule.

Therefore, the correct answer is d. Capsule.