Mutant polypeptides and uses thereof

A polypeptide comprising an amino acid sequence with at least 90% amino acid sequence homology to SEQ ID NO:

• 1, wherein said amino acid sequence comprises one to five mutations at the following X positions of SEQ ID NO:
• 1:
• R1-95X96R97-98X99R100-122X123R124-186X187R188-203X204R205-211X212R213-272X273X274X275R276-323X324R325-327X328R329-359X360R361-365X366R367-381X382R383-398, wherein:
• X96 is mutated to a different amino acid selected from L and equivalent amino acids;
• X99 is mutated to a different amino acid selected from L and equivalent amino acids;
• X123 is mutated to a different amino acid selected from I and equivalent amino acids;
• X187 is mutated to a different amino acid selected from M and equivalent amino acids;
• X204 is mutated to a different amino acid selected from I and equivalent amino acids;
• X212 is mutated to a different amino acid selected from F, Y, and equivalent amino acids;
• X273 is mutated to a different amino acid selected from C and equivalent amino acids;
• X274 is mutated to a different amino acid selected from F and equivalent amino acids;
• X275 is mutated to a different amino acid selected from I and equivalent amino acids;
• X324 is mutated to a different amino acid selected from L, E, and equivalent amino acids;
• X328 is mutated to a different amino acid selected from V and equivalent amino acids;
• X360 is mutated to a different amino acid selected from Y and equivalent amino acids;
• X366 is mutated to a different amino acid selected from V, C, G, and equivalent amino acids;
• X382 is mutated to a different amino acid selected from W and equivalent amino acids;
• and each R is the same as the corresponding amino acid in SEQ ID NO:
• 1, with or without an N-terminal signal peptide, and with or without an N-terminal methionine.