FIG. 1. Representation of the 5' region of the secondary structure
of 16S rRNA (0, 5' terminus). Conserved areas are drawn in
bold lines, and areas that vary in sequence and size are drawn in thin
lines (broken lines, structure found only in a few organisms) (10).
This part of the 16S rRNA contains the variable regions Vl, V2, and
V3. The location and direction of the PCR primers used in this study
are marked by arrows.