Patent ID: 8268598

Claim:
An isolated nucleic acid molecule comprising a nucleotide sequence encoding a Euglena gracilis delta-5 desaturase mutant polypeptide, wherein the mutant polypeptide comprises an amino acid sequence that has at least 95% amino acid sequence identity with the amino acid sequence of SEQ ID NO:8, wherein the amino acid sequence of the mutant polypeptide has Gly or His at the position corresponding to amino acid 34 of SEQ ID NO:8, and wherein said mutant polypeptide has delta-5 desaturase enzymatic activity and has a dihomo-γ-linolenic acid to arachidonic acid conversion efficiency that is greater than the dihomo-γ-linolenic acid to arachidonic acid conversion efficiency of a wildtype Euglena gracilis delta-5 desaturase polypeptide having the heme-binding motif as set forth as SEQ ID NO:180 (HPGG).