The present invention relates to the technical field of a method for preparing a recombinant
botulinum toxin type A, and particularly relates to a
botulinum toxin type A obtained by means of
gene recombination technology, the
amino acid sequence of which is identical to the sequence of
botulinum toxin type A prepared by means of extraction and purification from a wild
Clostridium botulinum strain. Provided is a single-chain
protein of
botulinum toxin type A, sequentially comprising: a light chain of
botulinum toxin type A or a modified light chain of
botulinum toxin type A, a linking region, and a
heavy chain of botulinum
toxin type A. The single-chain
protein is subjected to
fermentation, crude purification,
enzyme digestion, and fine purification to obtain high-quality recombinant botulinum
toxin type A. The present invention can solve the existing problems of complex process, long period, high
safety risk and the like in the preparation of botulinum
toxin type A by using wild
Clostridium botulinum strains, and also solve the existing problem that the
amino acid sequence of botulinum toxin type A prepared by means of
gene recombination technology cannot be identical to that of botulinum toxin type A prepared by wild
Clostridium botulinum strains.