ASPG and acute lymphoblastic leukemia: The L-asparaginases of Erwinia chrysanthemi and E. coli have been employed for many years as effective drugs in the treatment of acute lymphoblastic leukaemia and leukaemia lymphosarcoma [7], but their therapeutic response rarely occurs without some evidence of toxicity [8], suggesting the need to discover new L-asparaginases that are serologically different but have similar therapeutic effects.