STREPTOCOCCUS DIFFICILE IS A NONHEMOLYTIC GROUP-B, TYPE IB STREPTOCOCCUS

Whole-cell protein electrophoretic analysis of the type strain of Stre ptococcus difficile (LMG 15799) revealed that this organism was indist inguishable from Streptococcus agalactiae strains, Although LMG 15799( T) (T = type strain) was originally described as serologically untypea ble, we found that this strain was a group B streptococcus belonging t o the capsular polysaccharide antigen type Ib group. The biochemical r eactivity of S. difficile, which differed from the biochemical reactiv ity of typical S. agalactiae strains mainly by being less versatile, i s similar to the biochemical reactivity of other group B, type Ib stre ptococci isolated from poikilothermic animals, such as fish and frogs.