Serologic relationship of fimbriae among Enterobacteriaceae.

The existence of serological relationship of fimbriae among serotypes of the same genus and among genera of Enterobacteriaceae was determined by agglutination and absorption procedures. It was found that fimbriae of different serotypes of the same genus and among the genera a) Escherichia, Shigella and Klebsiella, and b) Salmonella, Arizona and Citrobacter were more or less antigentically related. No relationship was found among fimbriae of the Edwardsiella, Enterobacter, Hafnia, Serratia, Proteus and Providencia. It was also found that in Klebsiella, MS and MR fimbriae differed antigenically. On the basis of the results obtained nine antigentically distinct types of fimbriae were distinguished.