Polyphasic taxonomic characterization of Lactobacillus rossiae isolates from Belgian and Italian sourdoughs reveals intraspecific heterogeneity.
(GTG)5-PCR fingerprinting and pheS sequence analysis of 18 Lactobacillus rossiae isolates, mainly originating from Belgian and Italian artisan sourdoughs, revealed intraspecies grouping as evidenced by the delineation of three and two subgroups, respectively. On the other hand, 16S rRNA and rpoA gene sequence analysis and DNA-DNA hybridizations supported the accommodation of all isolates in a single species. No correlation between genetic and phenotypic heterogeneity was observed. Collectively, these data do not warrant taxonomic division of L. rossiae. On the other hand, the considerable differences in intraspecies sequence variation of L. rossiae isolates displayed by the pheS (9.8%) and rpoA (1.1%) genes highlight that the discriminatory power of housekeeping genes as alternative genomic markers for the 16S rRNA gene in the identification of Lactobacillus species may significantly differ from gene to gene. In conclusion, this study has demonstrated that a polyphasic approach remains highly useful for identification of isolates belonging to genotypically heterogeneous species such as L. rossiae.
Scheirlinck
Ilse
I
Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, K.L. Ledeganckstraat 35, 9000 Ghent, Belgium. Ilse.Scheirlinck@ugent.be
Van der Meulen
Roel
R
Vrancken
Gino
G
De Vuyst
Luc
L
Settanni
Luca
L
Vandamme
Peter
P
Huys
Geert
G
D015373:Bacterial Typing Techniques; D001530:Belgium; D001939:Bread / Q000382:microbiology*; D016172:DNA Fingerprinting / Q000379:methods; D004269:DNA, Bacterial / Q000032:analysis; D004275:DNA, Ribosomal / Q000032:analysis; D012321:DNA-Directed RNA Polymerases / Q000235:genetics; D007558:Italy; D007778:Lactobacillus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D010641:Phenotype; D010652:Phenylalanine-tRNA Ligase / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013045:Species Specificity
D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D012321:DNA-Directed RNA Polymerases; C113275:RNA polymerase alpha subunit; D010652:Phenylalanine-tRNA Ligase