ABSTRACT
Organisms belonging to the genus Salmonella are comprised of serologically diverse groups that are characterized by the presence of distinct lipopolysaccharide and flagella antigens upon their surfaces. The type 1 fimbrial antigens of Salmonella serovars are closely related. A closely related fimbrial antigen (or antigens) is also present on the type 1 fimbriae produced by isolates of Citrobacter. However, fimbrial specific antiserum, raised against Salmonella fimbriae, does not react with type 1 fimbriae from other genera of the Enterobacteriaceae. Type 2 fimbriae are found on a minority of Salmonella serovars and are most frequently associated with fimbriate strains of 5. pullorum and S. gallinarum. Type 3 fimbriae mediate the agglutination, in vitro, of erythrocytes that have been treated with tannic acid but do not agglutinate fresh, untreated erythrocytes. Many of the Salmonella serovars produce fimbriae that are implicated in mediating attachment to receptors on eukaryotic cells or extracellular matrices.
