Patent ID: 8778659

Claim:
A method of reducing glycosylation of insulin precursor or its analogs, wherein its analogs retain a biological property of insulin, represented by formula I X-B-Y-A wherein, X is a leader peptide sequence comprising at least one amino acid, B is the amino acid sequence of the B chain of the insulin molecule or analogs, Y is a linker peptide comprising at least one amino acid, A is the amino acid sequence of the A chain of the insulin molecule or analogs, and the A and B chain can be modified by amino acid substitution, deletion and/or additions; produced from a methylotrophic yeast enabled through inactivation of at least one of the genes selected from the group comprising PMT1 and PMT5 having a nucleotide sequence represented by SEQ ID Nos. 1 and 4 respectively, said sequences encode for the protein mannosyl transferase or a functional part thereof.