PfhB2 of strain P1059 has been shown to play an important role in either colonization or invasion in the turkey model [34]. Also, vaccination with recombinant P1059 PfhB2 peptides cross protected turkeys against an X73 challenge [35]. PfhB2 was present in strain Pm70, P1059, and X73, but was only 90% similar in the latter two as compared to Pm70. Overall, the presence of unique genes/systems related to metabolism and adhesion could provide strains such as P1059 with additional tools for increased fitness leading to higher virulence.

Figure 3 Dendrogram depicting amino #find more randurls[1|1|,|CHEM1|]# acid sequence similarities between the filamentous heagglutinins of Pasteurella multocida . Evolutionary history was inferred using the Maximum Likelihood method based on the JTT matrix-based model. The tree is drawn to scale, and 500 bootstrap iterations were performed. A total of 1,479 positions were used in the final dataset. The analyses were conducted in MEGA [Tamura et al. 2007]. Proteins from P. dagmatis were included for comparative purposes. Of the 127 unique proteins identified in strain X73

were five genes for a galactitol-specific phosphotransferase Selleckchem INCB018424 and utilization system (00310 to 00316), only present in strain X73; three genes for a TRAP dicarboxylate transporter system (01441 to 01443), also present in strain 36950; and six genes for a novel simple sugar D-allose transport and utilization systems (00951 to 00956), only present in strain X73. Such systems could again provide additional means of energy production in a resource-limited environment. Known virulence factors and antigens Comparisons were performed for several known virulence factors and outer membrane proteins that are important for P. multocida pathogenesis, functionality, and vaccine development [52].

These comparisons revealed some noteworthy aspects relative to their presence and evolution in P. multocida. For example, the hemoglobin receptors hgbA and hgbB were present in all sequenced P. multocida genomes, but are significantly different HSP90 in their amino acid similarities (Table 3). HgbA and HgbB have been shown to exhibit hemoglobin binding properties [53, 54]. Their incomplete distribution reported in previous studies could be attributed to genetic variation rather than complete absence of these genes [55]. The outer membrane porins ompH1 and ompH2 were also present in all sequenced strains, with ompH2 more highly conserved than ompH1 with respect to amino acid similarity. Furthermore, a third outer membrane porin ompH3 was present in all sequenced strains except strain X73, but was highly conserved within these strains. The ptfA gene, encoding a type 4 fimbrial subunit, was highly conserved in all sequenced strains, as was comE encoding a fibronectin-binding protein. The pfhB1 gene, encoding a filamentous hemagglutinin protein, was present in strains Pm70, P1059, X73, and 3480. PfhB1 was highly conserved among these strains.