Patent ID: 11969512
Assignee: SANYO CHEMICAL INDUSTRIES, LTD.
Field: Biotechnology (Chemistry)
Classification: CPC A  C | IPC A  C

Claim 0:
1. A method for producing a protein composition containing a protein (A), a radical scavenger (RS), and at least one hydrogen-bond-formable compound (HC) selected from the group consisting of amino acids, peptides, and proteins other than the protein (A),
the method comprising:
a sterilization step of radiosterilizing a freeze-dried and unsterilized protein composition,
wherein the unsterilized protein composition contains the protein (A), the radical scavenger (RS), and the hydrogen-bond-formable compound (HC),
the protein (A) contains at least one functional group selected from the group consisting of sulfide, amide, hydroxyl, amino, and carboxyl groups,
the hydrogen-bond-formable compound (HC) contains at least one functional group selected from the group consisting of sulfide, amide, hydroxyl, amino, and carboxyl groups,
the at least one functional group in the protein (A) is capable of binding to the at least one functional group in the hydrogen-bond-formable compound (HC) via a hydrogen bond,
the unsterilized protein composition has a water content of 0 to 30% by weight based on the weight of the unsterilized protein composition,
a weight ratio of the radical scavenger (RS) to the protein (A) in the unsterilized protein composition is 0.01 to 1.0,
a molar ratio of a total molar number of functional groups in the hydrogen-bond-formable compound (HC) to a total molar number of functional groups in the protein (A) in the unsterilized protein composition is 0.05 to 0.50,
the method further comprises a freeze-drying step performed before the sterilization step,
in the freeze-drying step, a water solution containing the protein (A), the radical scavenger (RS), and the hydrogen-bond-formable compound (HC) is freeze-dried to the unsterilized protein composition, and
the protein (A) is SELP 8K containing an amino acid sequence represented by SEQ ID NO: 22.