The 110Â kDa glutathione transferase of Yarrowia lipolytica is encoded by a homologue of the TEF3 gene from Saccharomyces cerevisiae: Cloning, expression, and homology modeling of the recombinant protein

The TEF4 gene of the non-saccharomyces yeast Yarrowia lipolytica encodes an EF1Bγ protein with structural similarity to the glutathione transferases (GSTs). This 1203 bp gene was cloned, over-expressed in Escherichia coli, and the recombinant protein characterized. DNA sequencing of the cloned gene agreed with the recently completed Y. lipolytica genome and showed 100% identity to a previously reported 30-residue N-terminal sequence for a 110 kDa Y. lipolytica GST, except that it encoded two additional N-terminal residues (N-Met-Ser-). The recombinant protein (subunit Mr 52 kDa) was found not to possess GST activity with 1-chloro-2,4-dinitrobenzene. Partial tryptic digestion released two fragments of Mr 22 and 18 kDa, which we interpret as N- and C-terminal domains. Homology modeling confirmed that the N-terminal domain of Y. lipolytica TEF4 encodes a GST-like protein.