Applied Biochemistry and Biotechnology

, Volume 110, Issue 1, pp 11–21 | Cite as

l-Asparaginase release from Escherichia coli cells with aqueous two-phase micellar systems



A method was proposed to release and separate l-asparaginase (EC from Escherichia coli ATCC 11303 cells with aqueous two-phase micellar systems. The systems were composed of K2HPO4 and Triton X-100. The method combines enzyme release with enzyme purification. The influence of Triton X-100 concentration, K2HPO4 concentration, and pH on the release and partition of l-asparaginase was investigated. Experimental results showed that E. coli cells treated with 9.4% (w/v) K2HPO4 and 15% (w/v) Triton X-100 at 25°C for 15–20 h released nearly 80% of the enzyme. Most of the released enzyme was partitioned to the bottom phase (phosphate-rich phase). The effects of Triton X-100 concentration, K2HPO4 concentration, and pH on cloud point were also studied. Electron micrography indicated that the chemical treatment altered the inner structure of E. coli cells significantly.

Index Entries

l-Asparaginase enzyme release Escherichia coli aqueous two-phase micellar system dipotassium hydrogen phosphate Triton X-100 


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Copyright information

© Humana Press Inc. 2003

Authors and Affiliations

  1. 1.School of PharmacyShanghai Jiao Tong UniversityShanghaiP. R. China

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