FIG 1.

Schematic of the upstream regions of the glmS and nagB genes (A) and alignment of sequences of NagR from S. mutans and YvoA/NagR from B. subtilis (B). (A) The locations of the predicted promoter elements are underlined and labeled as −35, −10, and +1 (transcription initiation site), and the start codon of each gene is represented by an arrow. The putative binding sites (dre1 and dre2) (see Table S2 in the supplemental material for the consensus sequence) for NagR are shown in boxes and labeled, with engineered modifications described below in italics. Also delineated are deletions and insertions introduced to alter the phasing of the dre sites. (B) Underlined are sites of mutations engineered in the DNA-binding domain (aa 2 to 69) near the N terminus of NagR and random mutations isolated in the putative effector-binding domain (aa 88 to 226) near the C terminus.