The present invention is directed to a biological conjugate, comprising: (a) a targeting
moiety comprising a polypeptide having an
amino acid sequence comprising the polypeptide sequence of SEQ ID NO:2 and the polypeptide sequence of a selected targeting
protein; and (b) a binding
moiety bound to the targeting
moiety; the biological conjugate having a
covalent bond between the
thiol group of SEQ ID NO:2 and a functional group in the binding moiety. The present invention is directed to a biological conjugate, comprising: (a) a targeting moiety comprising a polypeptide having an
amino acid sequence comprising the polypeptide sequence of SEQ ID NO:2 and the polypeptide sequence of a selected targeting
protein; and (b) a binding moiety that comprises an adapter
protein, the adapter protein having a
thiol group; the biological conjugate having a
disulfide bond between the
thiol group of SEQ ID NO:2 and the
thiol group of the adapter protein. The present invention is also directed to biological sequences employed in the above biological conjugates, as well as pharmaceutical preparations and methods using the above biological conjugates.