Clostridium butyricum engineering strain for treating colorectal cancer and application thereof

Abstract

To solve the technical problem of efficient expression of CLMP protein in tumors in the prior art, the application initiatively provides Clostridium butyricum engineering strains. The engineering strains take Clostridium butyricum ATCC19398 as a chassis strain and comprise a recombinant expression vector for expressing CLMP protein. The inventors have unexpectedly found that the Clostridium butyricum as a chassis strain can realize the expression of CLMP in tumor cells, fundamentally solving the technical problem of decreased expression of CLMP protein in colorectal cancer, and having important significance for the treatment of colorectal cancer. On this basis, the inventors realize the enrichment of Clostridium butyricum in tumors by knocking out purM, a gene related to purine synthesis in the Clostridium butyricum; further, by knocking out the protease gene lon, the expression amount of CLMP protein is significantly increased while meeting the precise positioning for tumors, thereby further improving the inhibition effect on tumors. Furthermore, the engineering strains can significantly inhibit the growth of tumors in a mouse model and have good safety, providing a new idea for the treatment of colorectal cancer and having important practical application value.

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