FIG.1.
Structural organization and gene disruption strategy of conserved ORFs within potential competence loci in the genome of T. thermophilus HB27. Physical map of mutant loci that are involved (A) and not involved (B) in natural transformation. In the restriction maps of gene bank plasmids covering different conserved ORFs of the potential competence loci, only selected restriction sites are shown. The triangle indicating the kat gene denotes the insertion site of the Kmr marker gene. The arrows denote direction of transcription. +, wild-type transformation frequencies; ±, 100-fold-reduced transformation frequencies; −, not transformable. BI, BamHI; BII, BglII; EV, EcoRV; HII, HincII; HIII, HindIII; N, NcoI; P, PstI; XI, XbaI.