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Methanol Independent Expression by Pichia Pastoris Employing De-repression Technologies
Published on: January 23, 2019
Molecular characterization of the Tim9 homologue from the methylotrophic yeast Pichia methanolica
Yoshimi Matsufuji1, Tomoyuki Nakagawa, Takashi Ito
1Department of Food Science and Technology, Faculty of Bioindustry, Tokyo University of Agriculture, 196 Yasaka, Abashiri, Hokkaido 099-2493, Japan.
Abstract:
In this paper we describe molecular characterization of the TIM9 gene encoding the essential mitochondrial inner-membrane protein in the methylotrophic yeast Pichia methanolica. PmTIM9 contains two exons corresponding to a gene product of 89 amino acid residues and a 140 bp intron. The deduced amino acid sequence exhibited high identity to those of other yeast Tim9ps, and possessed two CX(3)C motifs that contained two cysteine residues conserved among small Tim family proteins. Moreover, PmTIM9 had the ability to partially suppress the temperature sensitivity of Saccharomyces cerevisiae strain tim9-3, suggesting that PmTIM9 is a functional homologue of the ScTIM9 gene.
Insights
We characterized the TIM9 gene in Pichia methanolica, identifying a protein essential for mitochondrial inner membranes. This yeast TIM9 protein is functionally similar to its counterpart in Saccharomyces cerevisiae.
Area of Science:
- Molecular biology
- Yeast genetics
- Mitochondrial biogenesis
Background:
- The TIM9 gene encodes an essential protein of the mitochondrial inner membrane.
- Understanding TIM9 function is crucial for mitochondrial biogenesis and cellular respiration.
Purpose of the Study:
- To perform molecular characterization of the TIM9 gene in Pichia methanolica.
- To investigate the functional conservation of PmTIM9 in yeast.
Main Methods:
- Gene sequencing and analysis of Pichia methanolica.
- Amino acid sequence comparison with other yeast Tim9 proteins.
- Functional complementation assay in Saccharomyces cerevisiae.
Main Results:
- The Pichia methanolica TIM9 (PmTIM9) gene consists of two exons and a 140 bp intron.
- The deduced PmTIM9 protein (89 amino acids) shares high identity with other yeast Tim9 proteins and contains conserved CX(3)C motifs.
- PmTIM9 partially suppressed the temperature-sensitive phenotype of Saccharomyces cerevisiae tim9-3.
Conclusions:
- PmTIM9 is an essential mitochondrial inner-membrane protein in Pichia methanolica.
- PmTIM9 is a functional homologue of Saccharomyces cerevisiae TIM9, indicating conserved function across yeast species.
