Recombinant P. multocida proteins tested as vaccine candidates in chickens.

a- Gene numbers are from the Pm70 strain [28] homolog of the X-73 genes amplified and cloned.b- Expression vectors: pBAD-DEST49, a Gateway® destination vector that features a thioredoxin fusion tag; pDEST-41BA a modified Gateway-adapted expression vector containing a NusA solubility tag [20] (originally derived from pLIC-NusA [48]); pDEST-17, a Gateway® destination vector for production of tagless native protein.c- I = insoluble; S = soluble protein.d- SignalP server signal peptide prediction. In general PCR primers were designed so as to amplify the gene region encoding the mature length protein, excluding the signal sequence, except where a signal sequence could not be predicted; in this case the primers were designed to encompass the entire gene.e- immunogenic reaction against the recombinant protein.f- serum reacted with a protein of appropriate size in a whole cell lysate derived from P. multocida grown in vitro at 37°C.g- positive (X-73 whole killed cells) and negative controls used in the vaccine trial.h- Due to its large size, PM0714 was purified in three overlapping sub-fragments spanning the entire protein.