<prompt> Ehrlich phenomenon is seen in:-ProteusMycobacterium TBCorynebacteriumStaphylococcus  <response>: Ehrlich phenomenon is seen in Corynebacterium. Option 1, 2, 4 Proteus, Mycobacterium species and Staphyococcus species: Do not show Ehrlich phenomenon. Proteus shows Dienes phenomenon. Option 3 Difference due to the presence of toxin preparation of varying amounts of toxoid and antitoxin to combine in varying propoions is called Ehrlich phenomenon. Minimum lethal dose MLD of the diphtheria toxin as the least amount of toxin required to kill a guinea pig weighing 250 g within 96 hrs after subcutaneous inoculation. One unit of antitoxin is defined as the smallest amount of antitoxin required to neutralize 100 MLD of toxin. 