abstract |
(57) Abstract: A lysine B containing substantially no impurities is provided. A recombinant ricin B containing no castor cell material, which is produced by E. coli or yeast cells transformed with a DNA encoding ricin B, and a method for producing the same. Provided. This method comprises the steps of (a) culturing E. coli or yeast cells transformed with an expression vector containing a DNA encoding ricin B, and (b) recovering ricin B from the resulting culture solution. Including steps. |