True statements about Pneumococcus are all except?
High-Yield Explanation
Ans. is 'd' i.e., The virulence of pneumococci is dependent only on the production of the capsular polysaccharide . Pneumolysin is a thiol-activated toxin, exes a variety of effects on ciliary cells and PMNs and also activates the classic complement pathway by direct binding of CI q. . Autolysin may contribute to the pathogenesis of pneumococcal disease by lysing bacteria. . Anti capsular antibody provides the best specific protection against pneumococcal infection i.e. anticapsular antibodies are serotype specific. . The virulence of Pneumococci is dependent not only on the production of the capsular polysaccharide but also on the production of pneumolysin, IgA, Protease. Remember ? . The most impoant antigen of the pneumococcus is the type specific capsular polysaccharide. . This polysaccharide is also called as 'specific soluble substance (S.S.S.)'. Pneumococci are classified into types based on the antigenic nature of the capsular polysaccharide. . Type 3 is most virulent. Quellung reaction - In the presence of homologous antiserum, the capsule becomes apparently swollen, sharply delineated and refractile.