Muteins of apolipoprotein D
A method for generating a mutein of human apolipoprotein D having detectable affinity to a given non-natural ligand of apolipoprotein D is disclosed, which comprises the steps of: (a) subjecting the apolipoprotein D to mutagenesis at the sequence positions 34 to 38, 60, 62 to 66, 68, 89 to 93, 115, 117 to 121, and 123 resulting in a plurality of muteins of apolipoprotein D; and (b) enriching resulting muteins having binding affinity for a given ligand from the plurality of muteins by selection, and/or isolating said mutein. Muteins of apolipoprotein D obtainable by this method are also disclosed.
1. A method for generating a mutein of human apolipoprotein D having detectable affinity to a given non-natural ligand of apolipoprotein D, comprising:
subjecting apolipoprotein D to mutagenesis at positions 34 to 38, 60, 62 to 66, 68, 89 to 93, 115, 117 to 121, and 123 of SEQ ID NO.: 22, resulting in a plurality of muteins of apolipoprotein D; and
selecting and/or isolating any resulting muteins having binding affinity for a given ligand from the plurality of muteins.
2. A method according to claim 1 , wherein said selecting comprises:
providing as given ligand a compound which is selected from the group consisting of a chemical compound in free or conjugated form that exhibits features of an immunological hapten, a peptide, a protein or another macromolecule,
contacting the plurality of muteins with said ligand in order to allow formation of complexes between said ligand and muteins having binding affinity for said ligand, and
removing muteins having no or no substantial binding affinity.
3. A method according to claim 1 , wherein the ligand is a protein.
4. A method according to claim 1 , wherein the selecting is carried out under competitive conditions.
5. A method according to claim 1 , wherein a nucleic acid coding for the plurality of muteins of apolipoprotein D, which nucleic acid results from mutagenesis, is operably fused at the 3′ end with a gene coding for the coat protein pIII of a filamentous bacteriophage of the M13-family or for a fragment of this coat protein, in order to select at least one mutein for the binding of the given ligand.