Multivalent heteromultimer scaffold design and constructs

A method of preparing self-assembling polypeptides from an albumin comprising:

• segmenting said albumin at one or more segmentation sites to obtain at least two albumin segments that self-assemble to form a quasi-native albumin structure, the method comprising the steps of
• a) selecting at least one loop of an albumin that has a high solvent accessible surface area and limited contact with the rest of the structure of said albumin, and
• b) introducing one segmentation site deleting zero to three amino acid residues at the segmentation site per selected loop to obtain at least two albumin segments having a complementary interface between the at least two albumin segments, wherein the interface is apolar, extensive and interdigitate.

A heteromultimer comprising:

• a first polypeptide construct comprising (i) a first transporter polypeptide comprising a first segment of albumin, and
• a second polypeptide construct comprising (iii) a second transporter polypeptide comprising a second segment of albumin,
• wherein a) said first segment of albumin and said second segment of albumin are obtained by segmentation of an albumin polypeptide at a segmentation site to delete zero to 3 amino acid residues at the segmentation site, b) said first transporter polypeptide and said second transporter polypeptide are different from each other, and c) said first transporter polypeptide and said second transporter polypeptide self-assemble to form a quasi-native structure of albumin.