Ehrlichia chaffeensis 28 kDa outer membrane protein multigene family

DNA encoding one or more P28 proteins from Ehrlichia chaffeensis, wherein said proteins have amino acid sequences selected from the group consisting of SEQ ID NO:

• 2, SEQ ID NO:
• 3, SEQ ID NO:
• 4, SEQ ID NO:
• 5, SEQ ID NO:
• 6, SEQ ID NO:
• 7, SEQ ID NO:
• 8, SEQ ID NO:
• 9, SEQ ID NO:
• 10, SEQ ID NO:
• 11, SEQ ID NO:
• 12, SEQ ID NO:
• 13, SEQ ID NO:
• 20, and SEQ ID NO:
• 21, wherein said DNA is selected from the group consisting of:
• (a) isolated DNA which encodes said P28 proteins;
• (b) isolated DNA which hybridizes to isolated DNA of (a) above under high stringency conditions consisting of hybridization a t 42° C. in the presence of about 50% formamide, a first wash at 65° C. with 2×SSC containing 1% SDS and a second wash at 65° C. with 0.1×SSC, and which encodes said P28 proteins;
• and
• (c) isolated DNA differing from the isolated DNAs of (a) and (b) above in codon sequence due to the degeneracy of the genetic code, and which encodes said P28 proteins.