DIAGNOSTIC POTENTIAL OF SEFA DNA PROBES TO SALMONELLA-ENTERITIDIS ANDCERTAIN OTHER O-SEROGROUP D1 SALMONELLA SEROVARS

Salmonella enteritidis thin fimbriae, SEF14, were found to be restrict ed to S. dublin and the predominantly poultry-associated members of th e Salmonella O-serogroup D1, S. enteritidis, S. berta, S. gallinarum a nd S. pullorum, when tested by Western and ELISA analyses from among 9 0 Salmonella isolates of 42 serovars, as well as from members of sever al related genera of the Enterobacteriaceae. These five serovars and a single isolate of S. typhi (D1) were also detected by hybridization o f genomic DNA from 732 Salmonella isolates of 117 serogroups to gene p robes derived from the S. enteritidis sefA (fimbrin gene), sefB (chape rone) or sefC (outer membrane protein) genes encoding proteins involve d in SEF14 biosynthesis. None of 250 Enterobacteriaceae or 27 other eu bacterial isolates tested hybridized to the sef probes. The sefA, sefB and sefC genes were amplified from these six Salmonella serovars by P CR using primer pairs designed from sefA, sefB or sefC of S. enteritid is. DNA sequencing of sefA genes from these five serovars indicated li mited sequence variability among sefA genes and recognition of individ ual base pairs which could potentially differentiate certain strains o f S. enteritidis, S. dublin and S. gallinarum. (C) 1996 Academic Press Limited