Fig 2.

The 5′-noncoding and amino-terminal-coding sequences are conserved among erp operons. (A) Alignment of 5′-noncoding DNAs of 13 representative erp operons. Nucleotides occurring in >50% of all loci are boxed in blue. The ATG initiation codon of the proximal erp gene is on the right. On the far right are indications of whether each operon contains one or two erp open reading frames and the relative sizes of those sequences (S, small-sized erp; M, medium-sized erp; L, large-sized erp). The promoter −10 and −35 sites and the high-affinity binding sites of the regulatory factors BpaB, EbfC, and Bpur are indicated above the alignment (our unpublished results and references 79, 80, 81, and 82). (B) Alignment of 5′ ends of the erp alleles characterized below in Fig. 5A to C. Nucleotides occurring in >50% of all loci are boxed in blue. The green bar above the alignment indicates the codon for the lipid-modified cysteine of the mature lipoprotein. The leader polypeptide is encoded by nucleotides to the left of the cysteine codon, and localization/trafficking signals are encoded by the nucleotides to the right (85). The relative size of each gene is indicated to the left of the alignment.