METHODS FOR THE PRODUCTION OF 3-O-DEACTIVATED-4'-MONOPHOSPHORYL LIPID A (3D-MLA)

摘要

Herein is disclosed a method for producing lipopolysaccharide (LPS), comprising: (a) growing a culture of a deep rough mutant bacterial strain in a medium; (b) maintaining the culture in stationary phase for at least about 5 hr; (c) harvesting cells from the culture; and (d) extracting LPS from the cells. The method allows for the production of an LPS which can be used to produce a 3-O-deacylated monophosphoryl lipid A (3D-MLA) having at least about 20 mol% of the hexaacyl congener group. Also herein is disclosed a method of extracting lipopolysaccharide (LPS) from a culture of deep rough mutant bacterial strain cells, comprising: (a) extracting the cells with a solution consisting essentially of at least about 75 wt% of an aliphatic alcohol having from 1 to 4 carbon atoms and the balance water, thereby producing cells with reduced phospholipid content; and (b) extracting the cells with reduced phospholipid content with a solution comprising chloroform and methanol, thereby yielding a solution of LPS in chloroform and methanol (CM). This method provides LPS solutions in CM that have reduced phospholipid content and are produced by relatively simple and inexpensive process steps.