Receptor Binding Polypeptides

Abstract

Isolated polypeptides containing fragments of SARS CoV S protein and functional equivalents thereof. Also disclosed are isolated nucleic acids encoding the polypeptides, related expression vectors, related host cells, related antibodies, and related compositions. Methods of producing the polypeptide, diagnosing infection with a coronavirus, and identifying a test compound for treating infection with a coronavirus are also disclosed.

1 - 11 . (canceled) 
     
     
         12 . An isolated nucleic acid comprising a sequence encoding a polypeptide or a complement thereof, wherein the polypeptide comprises SEQ ID NO: 4 or an immunogenic fragment thereof, and the immunogenic fragment is at least 10 amino acid residues in length. 
     
     
         13 . The nucleic acid of  claim 12 , wherein the sequence contains SEQ ID NO: 3, 5, 6, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, or 27; or encodes one of the peptide sequences listed in Table 2. 
     
     
         14 . The nucleic acid of  claim 13 , wherein the sequence contains SEQ ID NO: 23 or 25. 
     
     
         15 . An expression vector comprising a nucleic acid of  claim 12 . 
     
     
         16 . A host cell comprising a nucleic acid of  claim 12 . 
     
     
         17 . A method of producing a polypeptide, comprising culturing the host cell of  claim 16  in a medium under conditions permitting expression of a polypeptide encoded by the nucleic acid, and purifying the polypeptide from the cultured cell or the medium of the cell, wherein the polypeptide comprises SEQ ID NO: 4 or an immunogenic fragment thereof, and the immunogenic fragment is at least 10 amino acid residues in length. 
     
     
         18 . (canceled) 
     
     
         19 . A method of generating an antibody against a polypeptide, the method comprising administering to a non-human animal a polypeptide or a nucleic acid encoding the polypeptide, wherein the polypeptide comprises SEQ ID NO: 4 or an immunogenic fragment thereof, and the immunogenic fragment is at least 10 amino acid residues in length. 
     
     
         20 . A method of inducing an immune response in a subject against a coronavirus, the method comprising administering to the subject a polypeptide or a nucleic acid encoding the polypeptide, wherein the polypeptide comprises SEQ ID NO: 4 or an immunogenic fragment thereof, and the immunogenic fragment is at least 10 amino acid residues in length. 
     
     
         21 - 24 . (canceled) 
     
     
         25 . A method of treating an infection with a coronavirus, the method comprising administering to a subject in need thereof an effective amount of a polypeptide, wherein the polypeptide comprises SEQ ID NO: 4 or an immunogenic fragment thereof, and the immunogenic fragment is at least 10 amino acid residues in length. 
     
     
         26 - 29 . (canceled)