Claims for Patent: 4,729,957

Summary for Patent: 4,729,957

Title:	Process for manufacture of L-asparaginase from erwinia chrysanthemi
Abstract:	A process for the recovery and purification of L-asparaginase from Erwinia chrysanthemi is disclosed. The process involves the preparation of cellular acetone powder extract followed by either an ion exchange and affinity chromatography purification steps or by affinity chromatography alone. The column eluent is then dialyzed to produce substantially pure L-asparaginase.
Inventor(s):	Lee; Shwu-Maan (Frederick, MD), Ross; John T. (Myersville, MD), Wroble; Marie H. (Mt. Airy, MD)
Assignee:	The United States of America as represented by the Department of Health (Washington, DC)
Application Number:	06/916,796
Patent Claims:	1. A process for purifying L-asparaginase from Erwina comprising the steps of: (1). Harvesting cells from both; (2). Permealizing the Erwina by mixing with acetone and passing acetone/cell mixture through a filter press at least once; (3). Rinsing the acetone/cell cake with buffer in the neutral pH range (pH 6.5-7.5) to remove acetone; (4). Rinsing cells with buffer in alkaline range; (5). Pass cells from step 4 through a cell press to extract the enzyme; (6). Clarify the enzyme containing fluid obtained in step 5 by in-line passage through filter bag loaded with Cell Debris Remover; (7). Purifying the enzyme on an affinity chromatography column. 2. A process of claim 1 wherein the organism used is Erwina Chrysanthemi. 3. A process of claim 1 wherein step 2 is performed twice. 4. A process of claim 1 wherein the chromatography column is an ion-exchange column. 5. A process of claim 1 wherein the column is an affinity bead column. 6. A process of claim 5 wherein the heads are sepharose Fast Flow beads. 7. A process of claim 1 wherein the buffer of step 4 is 10 mM borate at pH 9.5.

Details for Patent 4,729,957

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Recordati Rare Diseases, Inc.	ELSPAR	asparaginase	For Injection	101063	01/10/1978		2005-03-08