Method of producing a capsular polysaccharide having a pneumococcal serotype

摘要

A method of producing a capsular polysaccharide having a pneumococcal serotype, the method comprising: (a) culturing bacterial cells that produce a pneumococcal serotype while the pH of a culture broth in the range of 7.0 to 9.4 is maintained ; (B) end of the culture of step (a) at a time between when the absorbance of the culture broth remains constant and when the absorbance begins to decrease; (C) performing an additional crop from the culture broth of step (b) without pH adjustment until the pH of the culture broth reached a pH of 5.5 or lower; (D) adding a lysing agent to the culture broth obtained from step (c) to lyse the cells, precipitating the proteins and removing the precipitated proteins and cell debris to obtain a clarified cell lysate; and (e) isolating and purifying the capsular polysaccharide from the lysate obtained from step (d), where a pH adjuster is not used for protein precipitation.