| 摘要 |
<p>Molecules comprise (i) a polypeptide (such as calmodulin) which has calcium-dependent binding affinity for ligand and (ii) another polypeptide, the polypeptides preferably being joined by a peptide bond and produced by recombinant expression from a gene fusion. The molecules are useful in detection, immobilisation, targeting and purification, cell-labelling, and band-shift assays for determining binding of a member of a specific binding pair (sbp) for complementary sbp member. For purposes of band-shift assays, polypeptide (i) need not have calcium-dependent binding affinity for a ligand, but should have a dissociation constant for a ligand of 10nM or less, measured at a pH of between 6 and 9 at 20 °C. In an alternative embodiment, a calmodulin-binding polypeptide which is, or is derived from, mastoparan is joined, as polypeptide (i) instead of a binding polypeptide, to the other polypeptide.</p> |
