The invention discloses a recombinant bacillus displaying GCRV VP7 proteins on the surface of
bacillus subtilis GC5 and a preparation method. The preparation method comprises the following steps: (1) obtaining a present
epidemic strain type-II GCRV VP7
nucleotide sequence; (2) separating wide bacillus from the body of a
grass carp, determining the wide bacillus to be
bacillus subtilis, and naming the wide bacillus as
Bacillus subtilis GC5, CCTCC NO: M2014654; (3) constructing a fusion expression recombinant integrated carrier, wherein a vp7 sequence in recombinant plasmids is the
nucleotide sequence shown in SEQ ID No. 1; (4) preparing and authenticating recombinant
bacillus subtilis, CCTCC NO: M2014655; (5) inducing and authenticating the recombinant bacillus displaying VP7 on the surface. The
generation rate of spores is up to 100%, and the recombinant bacillus is simple and convenient to produce, low in cost, and capable of being used as a
feed additive; the recombinant bacillus has an intestinal customization capacity, as well as is beneficial to regulating the intestinal
bacterial colony balances of animals, improving the body
immunocompetence of the animals, and enhancing the
nutrition metabolism functions of the animals. The spores are high in
stress resistance and easy for large-scale production, as well as solve the problem of
instability of GCRV VP7 proteins used as immunizing antigens in extreme environments.