16S–23S rRNA intergenic spacer region sequence variation in Streptococcus thermophilus and related dairy streptococci and development of a multiplex ITS-SSCP analysis for their identification
The 16S–23S rRNA internal transcribed spacer (ITS) region of several Streptococcus thermophilus strains and some related dairy streptococci, S. macedonicus, S. salivarius and S. bovis, was analysed by sequence analysis. All the Streptococcus species were easily discriminated on the basis of sequence variations principally located upstream and downstream of the region encompassing the double-stranded processing sites and the tRNAAla gene. Comparison between tRNAAla gene sequences highlighted a high level of sequence conservation among the Streptococcus species investigated despite their belonging to separated phylogenetic clusters, i.e. the S. salivarius and S. bovis rRNA groups. A low but significant degree of variability was detected among the S. thermophilus strains, allowing the identification of four different ITS sequences. Similarity analysis of the ITS sequences showed that the Streptococcus species were clustered in two main branches, one containing S. macedonicus and S. bovis strains, and one containing S. thermophilus and S. salivarius strains. With the aim of developing a rapid tool for the identification of the dairy streptococci species a multiplex ITS-SSCP analysis of two discrete regions within the ITS locus was carried out.
AndrighettoC.,
BorneyF.,
BarmazA.,
StefanonB.,
LombardiA.2002; Genetic diversity of Streptococcus thermophilus strains isolated from Italian traditional cheeses. Int Dairy J 12:141–144
DaffonchioD.,
CherifA.,
BorinS.2000; Homoduplex and heteroduplex polymorphisms of the amplified ribosomal 16S-23S internal transcribed spacers describe genetic relationships in the “ Bacillus cereus group”. Appl Environ Microbiol 66:5460–5468
FarrowJ. A. E.,
KruzeJ.,
PhillipsB. A.,
BramleyA. J.,
CollinsM. D.1984; Taxonomic studies on Streptococcus bovis and Streptococcus equinus : description of Streptococcus alactolyticus sp.nov. and Streptococcus saccharolyticus sp. nov. Syst Appl Microbiol 5:467–482
MaesN.,
De GheldreY.,
De RyckR.,
VaneechoutteM.,
MeugnierH.,
EtienneJ.,
StruelensM. J.1997; Rapid and accurate identification of Staphylococcus species by tRNA intergenic spacer length polymorphism analysis. J Clin Microbiol 35:2477–2481
ManachiniP. L.,
FlintS. H.,
WardL. J. H.,
KellyW.,
FortinaM. G.,
PariniC.,
MoraD.2002; Comparison between Streptococcus macedonicus and S. waius strains and reclassification of Streptococcus waius (Flint et al ., 1999) as Streptococcus macedonicus (Tsakalidu et al ., 1998). Int J Syst Evol Microbiol 52:945–951
MoraD.,
FortinaM. G.,
NicastroG.,
PariniC.,
ManachiniP. L.1997; Genotypic characterization of thermophilic bacilli: a study on a new soil isolates and several reference strains. Res Microbiol 149:711–722
PoyartC.,
QuesneG.,
Trieu-CoutP.2002; Taxonomic dissection of the Streptococcus bovis group by sequencing the manganese-dependent superoxide dismutase gene ( sodA ) sequences: reclassification of ‘ Streptococcus infantarius subsp. coli ’ as Streptococcus lutetiensis sp. nov. and of Streptococcus bovis biotype II.2 as Streptococcus pasteurianus sp. nov. Int J Syst Evol Microbiol 52:1247–1255
Tilsala-TimisjärviA.,
AlatossavaT.1997; Development of oligonucleotide primers from the 16S-23S rRNA intergenic sequences for identifying different dairy and probiotic lactic acid bacteria by PCR. Int J Food Microbiol 35:49–56
TsakalidouE.,
ZoidouE.,
PotB.,
WassillL.,
LudwigW.,
DevriesL. A.,
KalantzopoulosG.,
SchleiferK. H.,
KerstersK.1998; Identification of streptococci from Greek Kasseri cheese and description of Streptococcus macedonicus sp. nov. Int J Syst Bacteriol 48:519–527
VaneechoutteM.,
RossauR.,
De VosP.7 other authors1992; Rapid identification of bacteria of the Comamonadaceae with amplified ribosomal DNA-restriction analysis (ARDRA). FEMS Microbiol Lett 93:227–234
16S–23S rRNA intergenic spacer region sequence variation in Streptococcus thermophilus and related dairy streptococci and development of a multiplex ITS-SSCP analysis for their identification