An Organism Differing from Shigella boydii 13 Only in Its Ability to Produce Gas from Glucose

It is generally accepted that, except for two biotypes of Shigella flexneri 6 (the Manchester and Newcastle biotypes), all members of the genus Shigella are anaerogenic. Two bacterial isolates are described which have O antigens identical to those of S. boydii 13 and which cannot be distinguished biochemically from typical strains of that biotype except by their ability to produce gas from glucose and other fermentable substances. The relationship between these strains and the typical S. boydii 13 is analogous to that between strains of the Manchester biotype and the typical S. flexneri 6.