Claims for Patent: 7,807,436

Summary for Patent: 7,807,436

Title:	Recombinant host for producing L-asparaginase II
Abstract:	The invention provides a recombinant Escherichia coli host cell for producing an Escherichia coli-asparaginase II enzyme. The host cell includes an Escherichia coli chromosome and at least one copy of a recombinant extrachromosomal vector, wherein the recombinant extrachromosomal vector encodes the L-asparaginase II enzyme, wherein the host cell chromosome also encodes the same L-asparaginase II enzyme, and wherein the host chromosome does not encode any other isoform of L-asparaginase II.
Inventor(s):	Filpula; David Ray (Piscataway, NJ), Wang; Maoliang (East Brunswick, NJ)
Assignee:	Defiante Farmaceutica, S.A. (Funchal-Madeira, PT)
Application Number:	11/759,988
Patent Claims:	1. A recombinant Escherichia coli host cell for producing an Escherichia coli L-asparaginase II enzyme, comprising an Escherichia coli host cell chromosome and at least one copy of a recombinant extrachromosomal vector, wherein the recombinant extrachromosomal vector encodes a subunit of the L-asparaginase II enzyme, wherein the host cell chromosome also encodes the same subunit of the L-asparaginase II enzyme, and wherein the host cell chromosome does not encode any other isoform of L-asparaginase II, wherein the encoded. L-asparaginase II subunit comprises SEQ ID NO: 1; and the recombinant extrachromosomal vector comprises a DNA molecule comprising SEQ ID NO: 2. 2. The recombinant Escherichia coli host cell of claim 1, wherein the extrachromosomal vector is a plasmid. 3. The recombinant Escherichia coli host cell of claim 1 wherein the DNA molecule is operatively connected to a suitable promoter. 4. The recombinant Escherichia coli host cell of claim 3 wherein the promoter is selected from the group consisting of T7, araB, P.sub.R/P.sub.L, phoA, trc, and trp promoters. 5. The recombinant Escherichia coli host cell of claim 3 wherein the recombinant extrachromosomal vector further comprises an operator, ribosome binding site, signal sequence, transcriptional terminator, antibiotic selection marker, origin of replication, and a regulated copy of the repressor. 6. The recombinant Escherichia coli host cell of claim 3 wherein the host cell chromosome comprises a DNA molecule according to SEQ ID NO:3. 7. An isolated nucleic acid molecule encoding an L-asparaginase II enzyme subunit of SEQ ID NO: 1, wherein the isolated nucleic acid molecule comprises a nucleic acid selected from the group consisting of SEQ ID NO: 2 and SEQ ID NO: 3. 8. A recombinant extrachromosomal vector, wherein the recombinant extrachromosomal vector comprises SEQ ID NO: 2, and encodes a subunit of the L-asparaginase II enzyme. 9. The recombinant extrachromosomal vector of claim 8 wherein the vector is a plasmid. 10. The recombinant extrachromosomal vector of claim 8 wherein the vector is plasmid pEN537. 11. An Escherichia coli host cell comprising the plasmid of claim 10, that is designated as EN538 and deposited as ATCC Number PTA 7490. 12. A method of producing a recombinant L-asparaginase II enzyme substantially free of other L-asparaginase II isomers, comprising culturing the host cell of claim 11, and isolating the produced L-asparaginase II enzyme. 13. An isolated DNA molecule encoding a subunit of L-asparaginase II enzyme that comprises SEQ ID NO: 2. 14. The recombinant extrachromosomal vector of claim 8 wherein SEQ ID NO: 2 is operatively connected to a suitable promoter. 15. The recombinant extrachromosomal vector of claim 14 wherein the promoter is selected from the group consisting of T7, araB, P.sub.R/P.sub.L, phoA, trc, and trp promoters.

Details for Patent 7,807,436

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Recordati Rare Diseases, Inc.	ELSPAR	asparaginase	For Injection	101063	01/10/1978		2026-06-30