The invention relates to a preparation method for oral recombinant nutritive polypeptide supplementing
human body essential amino acids, and belongs to the technical field of recombination
fusion protein medicines. The preparation method comprises integrating a nutritive polypeptide
gene np bringing with an enterokinase
label into a pJS700 vector, then using a
spore capsid protein gene cotC as a
molecular vector and constructing fusion expression integrated type recombinant
plasmid, then performing conversion on
bacillus subtilis by using the fusion expression integrated type recombinant
plasmid, so as to enable the exogenous
gene to be integrated into
amylase gene in
chromosome, and screening out a recombinant
bacillus subtilis strain containing fusion expression cotC-NP, and displaying the nutritive polypeptide on the
spore surface by inducing the recombinant
bacterial strain. The constructed recombinant
spore with the enterokinase-labeled nutritive polypeptide displayed on the surface can be directly orally taken by animals or people and be freely digested and absorbed in intestinal tracts, becomes a novel oral sport
nutrition health product, and possesses wide application value. The limit that BCAA comes from
chemical synthesis extraction is overcome, and also the
disadvantage that separation purification is complex when the nutritive polypeptide is produced through recombination
fermentation is overcome.