Immobilization of microbial cells containing NAD-kinase

Abstract
Microbial cells having NAD‐kinase activity, Brevibacterium ammoniagenes, were immobilized by the radiation‐copolymerization method under low temperature with the activity recovery of more than 80%. Compared to the native microbial cells the immobilized cells were more stable against heat and pH change. The immobilized cells were subjected to the 5 hr reaction repeatedly 20 times without any activity loss.