The Peroxisomal Catalase Gene in the Methylotrophic Yeast<i>Pichia methanolica</i>

Abstract

In this paper, we describe the CTA1 gene, which encodes a peroxisomal catalase in the methylotrophic yeast Pichia methanolica. The P. methanolica CTA1 gene (PmCTA1) comprises a 1,530-bp open reading frame corresponding to a protein of 510 amino acid residues, and its deduced amino acid sequence shows high similarity to those of Cta1ps from other methylotrophic yeasts (about 79%). Expression of PmCTA1 in a peroxisomal catalase-depleted (Cbcta1Delta) Candida boidinii strain restored the methylotrophic growth of the host strain, while the expression of PmCTA1-DeltaSRL, which lacks peroxisome targeting signal type 1, did not. In P. methanolica, expression of PmCTA1 was induced when cells were grown on peroxisome-inducing carbon sources, viz., methanol, oleate, and D-alanine. Taken together, these results indicate that PmCTA1 encodes a functional peroxisomal catalase in P. methanolica.