title: 16S-23S rDNA intergenic spacer region polymorphism of Lactococcus garvieae, Lactococcus raffinolactis and Lactococcus lactis as revealed by PCR and nucleotide sequence analysis.
abstract: The intergenic spacer region (ISR) between the 16S and 23S rRNA genes was tested as a tool for differentiating lactococci commonly isolated in a dairy environment. 17 reference strains, representing 11 different species belonging to the genera Lactococcus, Streptococcus, Lactobacillus, Enterococcus and Leuconostoc, and 127 wild streptococcal strains isolated during the whole fermentation process of "Fior di Latte" cheese were analyzed. After 16S-23S rDNA ISR amplification by PCR, species or genus-specific patterns were obtained for most of the reference strains tested. Moreover, results obtained after nucleotide analysis show that the 16S-23S rDNA ISR sequences vary greatly, in size and sequence, among Lactococcus garvieae, Lactococcus raffinolactis, Lactococcus lactis as well as other streptococci from dairy environments. Because of the high degree of inter-specific polymorphism observed, 16S-23S rDNA ISR can be considered a good potential target for selecting species-specific molecular assays, such as PCR primer or probes, for a rapid and extremely reliable differentiation of dairy lactococcal isolates.
authors.affiliation: Dipartimento di Scienza degli Alimenti, Sezione di Microbiologia Agraria, Alimentare ed Ambientale e di Igiene, Università degli Studi di Napoli Federico II, Portici, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Blaiotta
authors.forename: Olimpia
authors.initials: O
authors.lastname: Pepe
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Mauriello
authors.forename: Francesco
authors.initials: F
authors.lastname: Villani
authors.forename: Rosamaria
authors.initials: R
authors.lastname: Andolfi
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Moschetti
mesh_terms: D001483:Base Sequence; D021901:DNA, Intergenic / Q000235:genetics; D004275:DNA, Ribosomal / Q000032:analysis; D005798:Genes, Bacterial; D017045:Lactococcus / Q000145:classification* / Q000235:genetics*; D013294:Lactococcus lactis / Q000235:genetics; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D012338:RNA, Ribosomal, 23S / Q000235:genetics*; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid
chemical_list: D021901:DNA, Intergenic; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D012338:RNA, Ribosomal, 23S