Relationship between E. coli HPF and B. burgdorferi BB0449. (A) E. coli HPF and BB0449 amino acid sequence alignment. Proteins have 26% identity (dark gray) and 46% similarity (light gray). Asterisks indicate amino acids involved in protein-ribosome interaction (23). (B) Genomic contexts of hpf in E. coli genome (strain MG1655, NC_000913.3) and bb0449 in B. burgdorferi genome on the chromosome (strain B31, NC_001318.1). The hpf gene and its homolog, bb0449, are shown in white; the gene for the conserved σ54 alternative sigma factor (rpoN) is in light gray; and other genes are in dark gray. Predicted functions of the gene products are indicated above the gene. LPS, lipopolysaccharide; PTS, phosphotransferase.