Biosynthetic proline/alanine random coil polypeptides and their uses

A nucleic acid molecule encoding a drug conjugate, the drug conjugate comprising

• (i) a random coil polypeptide consisting of proline and alanine amino acid residues, wherein the random coil consists of at least 150 proline (Pro) and alanine (Ala) amino acid residues;
• and
• (ii) a biologically active protein or a polypeptide with biological activity.

A method for the preparation of a random coil polypeptide

• consisting of proline and alanine amino acid residues, wherein the random coil consists of at least 150 proline (Pro) and alanine (Ala) amino acid residues, and wherein the random coil polypeptide is conjugated to
• a drug selected from the group consisting of (a) a biologically active protein or a polypeptide with biological activity and (b) a small molecule drug,
• said method comprising culturing a host cell comprising a nucleic acid molecule encoding the random coil polypeptide or a vector comprising the nucleic acid, and isolating said random coil polypeptide from the culture or from said cell.

A method for the production of a protein conjugate comprising:

• (i) a random coil polypeptide consisting of proline and alanine amino acid residues, wherein the random coil consists of at least 150 proline (Pro) and alanine (Ala) amino acid residues, and
• (ii) a biologically active protein or a polypeptide with biological activity,
• said method comprising cultivating a host cell comprising a nucleic acid molecule encoding the protein conjugate or a vector comprising the nucleic acid, and isolating the protein conjugate from the culture or from the host cell.