FIG. 5.

Purification of ribulose 5-phosphate reductase (ribotol 5-phosphate dehydrogenase) and CDP-ribitol pyrophosphorylase by chromatography on DEAE-Sepharose (A) and Blue-Sepharose (B). (A) A bacterial extract containing about 300 mg of protein was loaded onto the DEAE-Sepharose column, which was developed with a linear KCl gradient. (B) Fractions 26 to 32 of the DEAE-Sepharose column were loaded onto a Blue-Sepharose column; proteins were eluted with a stepwise NaCl gradient. Ribulose 5-phosphate (5-P) reductase (⧫) was measured in the presence of 50 μM CTP. CDP-ribitol pyrophosphorylase (PPase) (■), ribose 5-phosphate isomerase (▵), and the protein concentration (○) were also measured.