HIGH MOLECULAR WEIGHT .GAMMA.-POLY(GLUTAMIC ACID)

摘要

High molecular weight .gamma.-PGA is provided. The .gamma.-PGA is separated from cells of the .gamma.-PGA producing cell culture after first adjusting the pH of the cell-culture to a pH of less than about 3. Also, the viscosity of a .gamma.-PGA solution is increased by removing metal ions with a chelator. In addition, .gamma.-PGA is fractionated directly from a cell culture, such that the fractionated .gamma.-PGA has low polydispersity. Purified .gamma.-PGA is produced having a molecular weight of at least 2.5 x 106.