True about cornebacterium diphtheriae is all except?
Deep invasion is not seen
Eleks test is done for toxigenicity
Metachromatic granules are seen
Toxigenicity is mediated by chromosomal change
Ans. is 'd' i.e., Toxigenicity is mediated by chromosomal change . This has been asked so many times in most of the examinations :? . Toxigenicity of diphtheria is not due to chromosomal change, it is phase mediated. About other options . Diphtheria is a toxemia, the bacilli remain confined to the site of entry, where they multiply and form toxin. . Elek's gel precipitation test is an in vitro test for toxigenicity. . Metachromatic granules (volutin or babes Ernest granules) are seen.