Sj. Jordan et al., Use of single-strand conformation polymorphism analysis to examine the variability of the rpoS sequence in environmental isolates of salmonellae, APPL ENVIR, 65(8), 1999, pp. 3582-3587
The natural environment places its resident microflora under stress, which
may often result in adaptation by the microflora in order to increase the p
robability of survival. One such mechanism that has been postulated involve
s rpoS, which encodes a sigma factor that is known to enhance survival upon
exposure to stress. The present work aimed to examine the genetic variabil
ity of rpoS in a selection of Salmonella enterica subspecies environmental
isolates with an automated single-strand conformation polymorphism analysis
technique. The results indicated that sequence variation does occur and th
at these changes are mainly located in two areas: at the center and near th
e end of the coding region. The variability was generally at the single-bas
e level, although one strain (S. arizonae) did demonstrate significant diff
erences in nucleotide sequence.