A boy (age: 71/12 years) with acute lymphoblastic leukaemia developed thrombosis of the sinus sagitalis superior with secondary haemorrhagic infarction while on induction treatment with vincristine, prednisone, and asparaginase. Based on this report, the potential pathogenic mechanisms are discussed with respect to congenital prothrombotic defects as well as to the role of antileukaemic treatme...

Asparaginase catalyses the hydrolysis of the amino acid asparagine to aspartic acid and ammonia. The asparaginase enzyme preparation described in the Novozymes’ dossier is intended for use during food processing to reduce the level of asparagine and thereby to decrease the risk of acrylamide formation. Acrylamide is formed in food from asparagine and reducing sugars when food products are baked...

BACKGROUND Asparaginase is an effective antileukemic agent which is included in most front-line protocols for pediatric acute lymphoblastic leukemia (ALL) worldwide. Since asparaginase is a bacterial protein, it may induce formation of antibodies. The reported frequency of anti-asparaginase antibodies is highly variable: antibodies have been reported in as many as 79% of adults and as many as 7...

A novel fungal gene encoding the Rhizomucor miehei l-asparaginase (RmAsnase) was cloned and expressed in Escherichia coli. Its deduced amino acid sequence shared only 57% identity with the amino acid sequences of other reported l-asparaginases. The purified l-asparaginase homodimer had a molecular mass of 133.7 kDa, a high specific activity of 1,985 U/mg, and very low glutaminase activity. RmAs...

The objective of this study was to isolate halophilic bacteria with the ability to produce intracellular or extracellular L-asparaginase. A total number of 120 halophilic bacteria were isolated from 17 different saline habitats of Iran including salt lakes, wetlands, brine springs and deserts. Among these, 68 were able to grow in the presence of 1.5 M NaCl and 52 demonstrated the ability to gro...

The effect of Escherichia coli L-asparaginase on phytohemagglutinin (PHA)-induced transformation of human lymphocytes was studied. Transformation was remarkably suppressed by the enzyme when it was added to the cul ture not later than 24 hr after its initiation. The effective concentration was more than 0.2 i.u./tube. Guinea pig serum and L-0-aspartohydroxamic acid, an L-asparagine analog, have...

The enzyme asparaginase, which hydrolyses asparagine to aspartic acid, inhibited cell-free protein synthesis by reticulocyte lysates. The inhibition was rapid and complete when sufficient enzyme was added but could be prevented or reversed by the addition of asparagine. The initial effect of asparaginase appears to be a block in polypeptide chain elongation due to asparagine deprivation, but th...

Asparaginases catalyze the hydrolysis of asparagine to aspartic acid and ammonia. Enzymes with asparaginase activity play an important role both in the metabolism of all living organisms as well as in pharmacology. The main goal of this paper is to attempt a classification of all known enzymes with asparaginase activity, based on their amino acid sequences. Some possible phylogenetic consequenc...

Levels of asparaginase activity from developing pea leaves (Pisum sativum) were found to change on a daily basis, increasing during the light period and decreasing in the dark. During extended periods of light, high levels of activity were maintained, while prolonged dark reduced activity to a low value. Half-expanded leaves exhibited the greatest change in activity over the photoperiod. Very y...

A protein-free and normal protein test diet were fed to female C3H/He mice. The protein-free test diet lowered the level of asparagine in the serum of the mice and in the 6C3HED tumor. The effect of asparaginase on the 6C3HED tumor was compared in mice fed the protein-free test diet and those fed the normal protein test diet. A considerable enhancement of the asparaginase activity on the 6C3HED...