Phosphodeoxyribomutase from Escherichia coli

Phosphodeoxyribomutase has been purified 67‐fold from a thymine starved dra − thy − mutant of Escherichia coli K12. The ratio of activities towards Rib‐1‐ P and dRib‐1‐ P did not change during the purification procedure, indicating that the same protein catalyzes the reaction with both substrates. The activity was dependent on the addition of Mn ++ , Co ++ or Ni ++ ions. Activity was stimulated 10‐fold by addition of ribo‐ or deoxyribose‐1,5‐diphosphate; the addition of glucose‐1,6‐diphosphate enhanced the activity 3‐fold. A molecular weight of 32000 ± 3000 was estimated by gel‐filtration.