Numbers of protein homologs conserved among representative Ehrlichia spp. A Venn diagram was constructed showing the comparison of conserved and unique genes between Ehrlichia spp. as determined by reciprocal Blastp algorithm using an E-value of < 1e-10. Numbers within the intersections of different circles indicate protein homologs conserved within 2, 3, or 4 organisms. Species indicated in the diagram are abbreviated as follows: EHF a, Ehrlichia sp. HF; ECH b, E. chaffeensis Arkansas; EMU c, E. muris subsp. muris AS145; EmCRT d, E. muris subsp. eauclairensis Wisconsin.