Agarose gel electrophoresis of amplified 16S rDNA of L. helveticus strains digested with restriction endonuclease EcoRI. Lane 2, undigested 16S rDNA of L. helveticus ATCC 15009T; lane 3, EcoRI-digested 16S rDNA of L. helveticus ATCC 15009T; lane 4, ATCC 10386 undigested 16S rDNA; lane 5, ATCC 10386 digested 16S rDNA; lane 6, Lh33 undigested 16S rDNA; lane 7, Lh33 digested 16S rDNA; lane 9, Lh8 undigested 16S rDNA; lane 10, Lh8 digested 16S rDNA; lane 11, Lh45 undigested 16S rDNA; lane 12, Lh45 digested 16S rDNA; lane 13, Lh40 undigested 16S rDNA; lane 14, Lh40 digested 16S rDNA; lanes 1, 8, and 15, DNA molecular size markers (1-kb plus DNA ladder; Life Technologies Italia).