L-Asparaginase Lab Report

Introduction:

L-Asparaginase (L-asparagine amido-hydrolase; EC 3.5.1.1), belongs to the amidohydrolase family. It catalyzes the breakdown of L-asparagine to ammonia and L-aspartic acid. The ammonia produced can be quantified using a gas analyzer with ammonia sensing electrodes (Fraticelli and Meyerhoff, 1983) or the ammonia can be combined with α-ketogluterate to form L-glutamic acid using glutamate dehydrogenase. This reaction is marked with a decline in the NADH concentrationand is detected as a loss of absorbance at 340 nm. Thus the activity of L-Asparaginase can be determined and expressed as ASNU unites where one ASNU is defined as "The amount of L-Asparaginase that produces 1 micromole ammonia per minute under the conditions of the assay (pH=7±0.05;temperature= 37.0 ±0.5 ºC) (Pronk et al., 2008).

L-Asparaginase has two broad applications, one of which is in the food industry (WHO, 2008) where L-Asparaginase is used in the production of dough based products, such as cookies, and high starch containing products such as potato chips and french fries. This is done to reduce acrylamide formation which takes place at elevated temperatures of

A number of bacteria produce L-asparaginase, but not all of these enzymes have anti-tumour properties. The variation in anti-tumor activity has been related to the affinity of the enzyme for its substrate and the clearance rate of the particular type of enzymes. Commercially used enzymes are obtained from E. coli and Erwinia carotovora (Marlborough et al., 1975). ELSPAR, ONCASPAR,

ERWINASE & KIDROLASE are the brand names of L-asparaginase which are used as medicines. It is also used in the food industry as a mean to reduce the formation of acrylamide from the baked product under the brand name of "Acrylaway and Preventase” (Halliday, 2008). Lasparaginase is used for lowering the acrylamide level by hydrolysing the free asparagine