Patent ID: 8674073
Filing Date: 2014-03-18
Classification: B01D,B01J,C07K

Abstract:
1. An immunoglobulin-binding protein, comprising: a variant of the amino acid sequence of SEQ ID NO: 1 representing a modified C-domain of (a) the lysine residue of position 35 of SEQ ID NO: 1 or SEQ ID NO: 2 is substituted with an arginine residue; or (b) the lysine residues of positions 4, 7, and 35 of SEQ ID NO: 1 or SEQ ID NO: 2 are substituted with amino acids other than a lysine residue; or (c) one or more of amino acid residues of positions 40, 43, 46, 53, 54, and 56 of SEQ ID NO: 1 or SEQ ID NO: 2 are substituted with lysine residues, in addition to said modification (b); (d) in addition to the changes set forth as (a)-(c) above, the immunoglobulin-binding protein optionally comprises a substitution of the aspartic acid residue at position 37 of SEQ ID NO:1 or SEQ ID NO:2 with an amino acid residue other than aspartic acid; wherein said immunoglobulin-binding protein has an improved orientation for maintaining affinity for an immunoglobulin in immobilization of the protein on an insoluble carrier via amino groups of the protein as compared to a molecule which does not have said modifications (a)-(d).