In another embodiment, the invention features a purified or recombinant polypeptide comprising an amino acid sequence represented by the formula A B, wherein {HEAD ~ A} represents {TAIL ~ all} or the portion of the amino acid sequence designated by residues 24 193 of SEQ ID 
In another embodiment , the invention features a purified or recombinant polypeptide comprising an amino acid sequence represented by the formula A B , wherein { HEAD ~ A } represents { TAIL ~ all } or the portion of the amino acid sequence designated by residues 24 193 of SEQ ID
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH