Serum albumin-binding fibronectin type III domains
Fibronectin type III domains (FN3) that specifically bind to serum albumin, related polynucleotides capable of encoding serum albumin-specific FN3 domains, cells expressing the FN3 domains, as well as associated vectors, detectably labeled FN3 domains and FN3 domains fused to a heterologous moiety are useful in extending the half-life of molecules in diagnostic and therapeutic applications.
1. A protein comprising an amino acid sequence that is at least 90% identical to the amino acid sequence of SEQ ID NO: 51 or an amino acid sequence having 1, 2, 3, 4, 5, 6, 7, or 8 substitutions as compared to the amino acid sequence of SEQ ID NO: 51.
2. The protein of claim 1 , wherein the protein comprises an amino acid sequence that is at least 90% identical to the amino acid sequence of SEQ ID NO: 51.
3. The protein of claim 1 , wherein the protein is at least 95%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 51.
4. The protein of claim 1 , wherein the protein comprises an amino acid sequence that has 1, 2, 3, 4, 5, 6, 7, or 8 substitutions when compared to the amino acid sequence of SEQ ID NO: 51.
5. A pharmaceutical composition comprising the protein of claim 1 and a pharmaceutically acceptable carrier.
6. A kit comprising the protein of claim 1 .
7. A molecule comprising a first domain and a second domain, wherein the first domain comprises the protein of claim 1 and the second domain is a molecule that binds to a target protein other than human serum albumin.
8. The protein of claim 1 , wherein the protein is at least 95% identical to the amino acid sequence of SEQ ID NO: 51.
9. The protein of claim 1 , wherein the protein is at least 97% identical to the amino acid sequence of SEQ ID NO: 51.
10. The protein of claim 1 , wherein the protein is at least 98% identical to the amino acid sequence of SEQ ID NO: 51.
11. The protein of claim 1 , wherein the protein is at least 99% identical to the amino acid sequence of SEQ ID NO: 51.
12. The protein of claim 1 , wherein the protein comprises the amino acid sequence of SEQ ID NO: 51.
13. A method of detecting the presence of human serum albumin in a biological sample comprising contacting the biological sample with the protein of claim 1 and determining the binding of the biological sample to the protein.
14. A protein comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 51-53.
15. A protein comprising the amino acid sequence of SEQ ID NO: 52.
16. A protein comprising the amino acid sequence of SEQ ID NO: 53.