FIG.4.

Southern and Northern hybridization analyses. (a) Southern hybridization analysis of HindIII-digested genomic DNAs of 13 Lactobacillus and 8 Bifidobacterium species with the tuf gene fragment as a probe. Northern hybridization analysis of Lactobacillus RNA and transcription unit mapping of the tuf locus. In panel a, the sizes of hybridizing fragments are shown. The tested strain was the type strain (Table 1). In the top portion of panel b, all predicted open reading frames are indicated and are annotated with their database matches. The positions of the probes used in Northern blot experiments are indicated under the gene map. The transcripts are depicted as arrows; the arrows point to the 3′ end of the mRNA. The length of the arrow is proportional to the length of the mRNA derived from the Northern blots. The estimated sizes of the mRNAs are indicated. Hairpins indicate possible rho-independent terminators. The transcripts are positioned with respect to the gene map. The width of an arrow indicates the relative abundance of the mRNA species. bind., binding. The bottom portion of panel b shows Northern blot hybridization of RNA isolated from lactobacilli with probes corresponding to the open reading frames in the gene map. The sizes calculated for the hybridization signals are provided.