Differentiation of Salmonella phase 1 flagellar antigen types by restriction of the amplified fliC gene.

The large antigenic diversity (over 2,300 serotypes) expressed by Salmonella strains can probably be observed at the genetic level. The phase 1 flagellin gene fliC was amplified, and the amplified fragment was cleaved with a mixture of both endonucleases TaqI and ScaI. The restriction patterns observed allowed differentiation of flagellar types b, i, d, j, l,v, and z10. Flagellar group g (g,m, g,p, or g,m,s) could be differentiated from the other flagellar types. Flagellar types r and e,h could not be separated, although they could be distinguished from the other flagellar types studied. Practical applications of flagellar gene restriction are the distinction between serotype Gallinarum-Pullorum, which carries a cryptic gene for flagellar type g,m, and nonmotile Vi-negative variants of serotype Typhi, and the tentative assignation of nonmotile variants of Salmonella serotypes to a flagellar type.