Ribosomal operons are great tools for microbe community characterization and for microorganisms relationship study, particularly in the case of the acid lactic bacteria. The ribosomal operon of the probiotic strain Lactobacillus delbrueckii UFV H2b20 was partially characterized. A genomic library of this strain was constructed and the clones with partial ribosomal operon were sub-cloned using the shot-gun method for subsequent sequencing with the forward primer. The sequence analysis revealed that the 3' end of the rDNA 16S was following by the short spacer region 1 (16S-23S) and that the 3' end of the rDNA 23S was following by the short spacer region 2 (23S-5S), which preceded the rDNA 5S. In the flanking region of the rDNA 5S gene of this operon rrn, a region encoding six tRNAs was detected.
ribosomal operons; Lactobacillus; tRNA; acid lactic bacteria
