Question

Some pathogenic microorganisms encode proteins, such as the

Staphylococcus Protein A, that bind to immunoglobulin constant region domains with
high affinity. These microbial proteins provide a benefit to the microorganism by:

A. Preventing antibodies bound to the microbe from binding to Fc receptors on phagocytes
B. Blocking the binding of anti-microbial antibodies to the pathogen surface
C. Cleaving the antibody into fragments that separate the antigen-binding region from the effector function
D. Inducing aggregation of the anti-microbial antibodies by multivalent binding to the
pathogen-derived protein
E. Preventing the antibody from neutralizing the pathogen

Answer 1

Staphylococcus Protein A aids the pathogen by disrupting the normal function of antibodies, specifically by preventing the antibody-Fc receptor interaction that leads to phagocytosis by immune cells.

Step-by-step explanation:

The coorect option : b

Antibodies serve important roles in the immune response, including opsonization which enhances phagocytosis by providing a binding site for phagocytes, and initiating the complement cascade leading to pathogen destruction. The high-affinity binding of bacterial proteins, such as Staphylococcus Protein A, to the antibody's constant region (Fc region) interferes with these immune processes.

It prevents the opsonized antibodies from engaging Fc receptors on phagocytes, which is crucial for the initiation of phagocytosis. This mechanism allows the pathogen to circumvent immune system detection and clearance, thereby assisting in the survival and spread of the microorganism within the host.Blocking the binding of anti-microbial antibodies to the pathogen surface. By doing so, the pathogenic microorganism can avoid detection and destruction by the immune system.