Expression and purification method of high-quality 055: B5 serotype LPS

The invention belongs to the field of biochemistry and molecular biology, and discloses a high-quality 055: B5 serotype LPS expression and purification method. Comprising the following steps: directionally transforming a 055: B5 serotype escherichia coli strain, fermenting to generate 055: B5 serotype LPS, purifying to obtain a lipopolysaccharide refined pure solution, and carrying out gradient precipitation to obtain high-quality lipopolysaccharide. The invention establishes a method for obtaining a large amount of high-quality 055: B5 serotype LPS. And a large amount of polysaccharide chain high-quality LPS can be obtained at a time through a gradient precipitation separation method. Through the purification steps mentioned in the patent, the time required for purification is greatly shortened, and the production cost is also greatly reduced. And the 055: B5 serotype LPS with the purity of more than 97% can be efficiently produced in a large scale in a short time. 本发明属于生物化学与分子生物学领域，公开了一种高质量055:B5血清型LPS表达纯化方