FIG. 1.
Alignment of the E. coli minimal oriC with the corresponding region from V. cholerae chromosome I. The AT-rich sequence and the three 13-mer repeats L, M, and R found in E. coli (5) are indicated above the alignment. The 6-mer (A/T)GATCT boxes (80) are underlined. Other DnaA binding sites, i.e., R-boxes (53), I-boxes (52), and τ-boxes (61), are shown as boxed regions. Dam methylation sites (GATC) are shaded gray. The experimentally defined binding sites for integration host factor (IHF) (22) and factor for inversion stimulation (FIS) (65) in E. coli are indicated, and bases that match the consensus sequence are in boldface type. The single base difference between oriCIVc and oriCIVc* (see Materials and Methods) in the minimal origin region is shown below the two sequences. A gap introduced to maximize alignment of the two sequences is indicated by a dash in the sequence. Nucleotides that are identical in the two sequences are indicated by an asterisk below the two sequences.