Purity: > 95% by SDS - PAGE Format: Liquid. In 20mM Tris-HCl buffer(pH 8.0) containing 10% glycerol, 2mM DTT.. AnsA is the cytoplasmic asparaginase from Escherichia coli involved in intracellular asparagine utilization. Escherichia coli possesse two l-asparaginases: the cytoplasmic type I form (ansA) and the periplasmic type II form (ansB). AnsA (Type I asparaginase) is constitutively expressed and required for the growth of the bacteria on asparagine as the sole nitrogen source. Recombinant E.coli ansA protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.