A novel alkaline stable immunoglobulin binding protein

摘要

The present invention relates to immunoglobulin (Ig) binding proteins comprising at least one Ig binding domain having an amino acid selected from the group consisting of at least 1I, 11A, 11E, 11I, 35R, 35I and 42L. The invention further relates to an affinity matrix comprising an Ig binding protein of the invention. The present invention also relates to the use of said Ig binding protein or affinity matrix for affinity purification of immunoglobulin and to affinity purification methods using the Ig binding protein of the present invention.