Kauffmann (1947) has reviewed the extensive work of himself and several colleagues on the serology of the Escherichia coli group. According to this report, cultures from pathologic and normal sources could be typed serologically by a system patterned after that used with the genus Salmonella. Three kinds of antigens were used: the usual H and O antigens, and K antigens, which were either thermolabile (L and B) or thermostable (A) envelope or capsular substances.
This work is important in that it helps to clarify the serological picture of a puzzling group of organisms. It will be especially valuable from the phylogenetic point of view when it has been extended to show the interrelationships of Escherichia coli with other genera and species of the Enterobacteriaceae.
Kauffmann experienced great difficulty in determining the H antigens of the coli-group because of inability to obtain actively motile cultures. Only by use of U-tubes with 0.1 per cent agar were suitable antigens secured.