Method of constructing a recombinant Bacillus subtilis that can produce specific-molecular-weight hyaluronic acids

摘要

The present invention relates to the field of biotechnology engineering. It provides a method of constructing a recombinant Bacillus subtilis that can produce specific-molecular-weight hyaluronic acids. By integranted expression of hasA from Streptococcus zooepidemicus and overexpression of genes of HA synthetic pathway, tuaD, glmU and glmS, high yield HA production was achieved in the recombinant strain. Additionally, introduction and functional expression of the leech hyaluronidase in the recombinant strain substantially increased the yield of HA to 19.38 g·L−1. Moreover, HAs with a broad range of molecular weights (103 Da to 106 MDa) were efficiently produced by controlling the expression level of hyaluronidase using RBS mutants with different translational strengths. The method of the present invention can be used to produce low molecular weight HAs at large scale in industrial applications.

主权项

1. A recombinant B. subtilis that can produce specific-molecular-weight hyaluronic acid (HA), wherein a HA biosynthetic pathway coupled with a secretory expression system of hyaluronidase is constructed in said recombinant B. subtilis; and wherein the secretory expression level of said hyaluronidase is regulated by ribosome binding sites with different translational strengths so as to produce said specific-molecular-weight HA.