Microbiologie médicale et diagnostic

Microbial Amidases and their Industrial Applications: A Review

Abstract

Dina H El-Ghonemy

Among the pediatric cancer in developed countries, acute leukemia ¬constitutes the major part with affecting 30-45 per 1,000,000 children each year. The effect of treatment varies with differences in patients clinical, immunologic and genetic characteristics. Therefore, the search for efficient drugs to solve this problem is being continued worldwide. Although several kinds of treatments are available, enzyme therapy is equally effective. Enzymes have been used as drugs; likewise L-asparaginase and L-glutaminase had received much attention in recent years due to their anticarcinogenic potential. These enzymes constitute one of the most biotechnologically and biomedically important group of therapeutic enzymes accounting for about 40% of the total worldwide enzyme sales. Various sources are found to be good producers of the enzymes: bacteria, fungi along with some of the plant and animal species. Food and Drug Administration and World Health Organization have approved L-asparaginase for the effective treatment of acute lymphoblastic leukemia and lymphsarcoma. L-asparaginase and L-glutaminase break down L-asparagine or L-glutamine into L-aspartic acid or L-glutamic acid, respectively, and ammonia. L-asparagine depletion results in nutritional deprivation, inhibition of protein synthesis, and subsequent apoptotic cell death in lymphoblasts. On the other hand, the ability of L-asparaginase to selectively hydrolyzes L-asparagine into L-aspartateis a potential way to reduce the amount of free L-asparagine in the starting materials of food production, thus reducing the imminent risk of generating a potential carcinogenic and neurotoxic acrylamide that formed from L-asparagine and reducing sugars in carbohydrate-containing foods (such as snacks and biscuits) when they are heated above 120oC. Therefore, the present review is an attempt to compile information on the sources, antino plastic action and industrial application of microbial amidases enzymes.