Construction of a recombinant Bacillus subtilis strain expressing SpaA and CbpB of Erysipelothrix rhusiopathiae and evaluation of the strain immunogenicity in a mouse model.
- Author:
Zhonglin CHENG
1
;
Hao HUANG
1
;
Siyi CAO
1
;
Huahui SHI
1
;
Jiye GAO
1
;
Jixiang LI
1
Author Information
- Publication Type:Journal Article
- Keywords: Bacillus subtilis; CbpB; Erysipelothrix rhusiopathiae; SpaA
- MeSH: Animals; Bacillus subtilis/immunology*; Mice; Erysipelothrix/immunology*; Bacterial Proteins/immunology*; Bacterial Vaccines/genetics*; Erysipelothrix Infections/prevention & control*; Immunization; Mice, Inbred BALB C; Plasmids/genetics*; Immunogenicity, Vaccine; Administration, Oral; Antigens, Bacterial
- From: Chinese Journal of Biotechnology 2024;40(12):4521-4532
- CountryChina
- Language:Chinese
- Abstract: To construct a recombinant Bacillus subtilis strain expressing SpaA and CbpB of Erysipelothrix rhusiopathiae for oral administration, we constructed the recombinant plasmid pDG1730-CBJA by fusion PCR and seamless cloning. The plasmid was introduced into B. subtilis KC strain by natural transformation, and the recombinant strain KC-spaA-cbpB was screened out on the plate containing spectinomycin (sper) and confirmed by PCR and starch degradation test. The SpaA and CbpB expressed by KC-spaA-cbpB were detected by Western blotting and indirect immunofluorescence assay, and the genetic stability of the recombinant strain in mice was determined. The plasmid pMAD-∆sper with knockout of sper was constructed and transformed into KC-spaA-cbpB. The sper-deleted mutant strain KC-spaA-cbpB: : ∆sper was screened and identified, and its immunogenicity in a mouse model was evaluated by oral immunization. The results showed that the recombinant strain KC-spaA-cbpB was stable in mice, expressing SpaA on the cell surface and CbpB on the spore surface. KC-spaA-cbpB: : ∆sper expressed SpaA and CbpB. The mice vaccinated with the spores of KC-spaA-cbpB: : ∆sper had higher levels of SpaA and CbpB-specific IgG in the serum that those vaccinated with the wild-type spores 42 days after vaccination by gavage (P < 0.01). The protective rate of mice immunized with the recombinant spores was 67.5%. The results indicated that a recombinant B. subtilis strain expressing SpaA and CbpB of E. rhusiopathiae was successfully constructed, and the recombinant strain laid a foundation for the development of oral live vector vaccines for swine erysipelas.
