Figure 2
Phenotypic characterization of Salmonella Choleraesuis strains rSC0016. A Phenotype of ΔPcrp527::TT araC PBAD crp. Strain rSC0016 with the ΔPcrp527::TT araC PBAD crp mutation were grown on MacConkey maltose agar with and without 0.2% arabinose. B Phenotype of Δpmi mutation. LPS profiles of Δpmi mutant strains rSC0016 in NB grown with or without 0.2% mannose. Lanes: 1, wild-type C78-3; 2, rSC0016 with mannose; 3, rSC0016 without mannose. C Regulated decreased synthesis of LacI and regulated delayed synthesis of SaoA proteins in rSC0016(pS-SaoA) containing ΔrelA::araC PBAD lacI TT mutation. Strain rSC0016(pS-SaoA) were grown in NB with arabinose and mannose (Lane 1) and then diluted 1:10 into fresh NB without arabinose and mannose until OD600 to 0.8. The process was repeated for four times (Lane 2–5); each lane was loaded around 2.5 × 107 CFU bacteria. Synthesis of LacI and SaoA were detected by Western blot using correspondent antiserum. M: protein marker. D Phenotype of ΔasdA mutation. Growth curves of rSC0016 in LB with and without DAP. Growth was monitored by measuring OD600 at the indicated time intervals. E Synthesis of SaoA in Salmonella Choleraesuis vector rSC0011, rSC0016 and rSC0018. An equal amount of cells was subjected to SDS-PAGE analysis. Immunoblot was detected with SaoA—specific polyclonal antibody. Densitometry ratio was quantified using Image J software. M: protein Marker; 1: rSC0011(pS-SaoA); 2: rSC0016(pS-SaoA); 3: rSC0018(pS-SaoA); 4: rSC0011(pYA3493); 5: rSC0016(pYA3493); 6: rSC0018(pYA3493); GroEL was used as a control.