What genetic pecularity is there in pathogenic/ toxigenic strain of corynebacterium diphtheriae but not in nonpathogenic strain -
Presence of R-factor
Presence of gene
Integrated temperate phage
Presence of MDR gene
Ans. is 'c' i.e., Integrated temperate phage The toxigenicity of the diphtheria bacilli depends on the presence in it of corynephages (tox +). Nontoxigenic strains may be rendered toxigenic by infecting them with beta phage or some other larger phage.This is known as lysogenic conversion or phage conversion.