| abstract |
The invention provides an immunoglobulin binding protein derived from an L-protein with improved antibody dissociation rate under acidic conditions, and an affinity support employing this immunoglobulin-binding protein. More specifically, the invention relates to an immunoglobulin binding protein which contains at least one mutant of an immunoglobulin binding domain, and an affinity support containing a solid support bound to that immunoglobulin binding protein. immunoglobulin. This immunoglobulin binding domain mutant has a k-chain immunoglobulin chain binding activity consisting of an amino acid sequence having at least 85% identity to an amino acid sequence represented by one of the SEQ's ID No: 1 to 9, and having a given mutation. |