Chapter 31 : An Ordered Collection of Bacillus subtilis DNA Segments in Yeast Artificial Chromosomes

Figure 1

The ordered YAC clones containing B. subtilis DNA. The segments carried in individual YAC clones are represented by horizontal lines. They are placed according to their relationships with the neighboring clones and the B. subtilis genes they contain, but the extent of overlap between the segments has not been determined. YAC accession numbers are also mentioned. B. subtilis genes which hybridized with the corresponding YACs are indicated. Genetic position (in degrees) is given for dnaG, add, ctaD, spoOB, sdh, and gnt loci. Stars indicate markers which were identified in YAC clones by transformation of B. subtilis mutants. Filled and open circles represent left and right ends of inserts, respectively, which were (i) successfully isolated and (ii) shown to hybridize with the overlapping insert (except for inserts bordering the gaps). We failed to isolate one end of the insert carried on YAC 12-5 (carrying the thyA gene), possibly because of their toxicity for E. coli and aberrant amplification in vitro. One end of the insert from YAC 15-37 (close to terC), signalled by a vertical line, hybridized with the insert carried by YAC 15-634 (close to dal), which shows that it is composed of nonadjacent B. subtilis DNA segments. However, the neighboring clone, YAC 15-10, is likely to contain the segment adjacent to thyA. The positions of four gaps present in the collection are indicated by vertical arrows and letters G1 to G4. The numbers in parentheses refer to gap size.