Patent ID: 9617550
Date: 2017-04-11
CPC Classifications: C12N,C12Y

Claim:
1. An engineered stable strain of Pichia pastoris , comprising: a mutant OCH1 allele which is transcribed into a mRNA encoding for a mutant OCH1 protein, wherein said mutant OCH1 protein comprises a catalytic domain that is at least 95% identical to the amino acids corresponding to residues 45-404 of the amino acid sequence of SEQ ID NO: 2 and retains at least 90% of the α-1,6-mannosyltransferase activity of the wild type OCH1 protein comprising the amino acid sequence of SEQ ID NO: 2, wherein said mutant OCH1 protein lacks an N-terminal sequence for targeting said mutant OCH1 protein to the Golgi apparatus and lacks a membrane anchor domain at the N-terminal region of said mutant OCH1 protein, and wherein said engineered stable strain produces at least 90% homogeneous N-glycans.