• BMB Reports
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• v.42 no.5
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• pp.281-285
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• 2009

Peroxisomes play an important role in cellular defense systems and generate secondary messengers for cellular communication. Saccharomyces cerevisiae containing oleate-induced peroxisomes were subjected to buffer-soluble extraction and two chromatographic procedures, and a protein with antifungal activity was isolated. The results of MALDI-TOF analysis identified the isolated protein as peroxisomal 3-ketoacyl-CoA thiolase (ScFox3). Purified yeast ScFox3 exhibited thiolase activity that catalyzed the thiolytic cleavage of 3-ketoacyl-CoA to acetyl-CoA and acyl-CoA. ScFox3 protein inhibited various pathogenic fungal strains, with the exception of Aspergillus flavus. Using ScFox3-GFP and PTS2 signal-truncated ScFox3M-GFP, we showed that only ScFox3-GFP, with an intact PTS2 peroxisome signal sequence, was able to translocate into peroxisomes. Yeast ScFox3 is a natural antifungal agent found in peroxisomes.

• Journal of Life Science
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• v.24 no.10
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• pp.1055-1062
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• 2014

We investigated the expression of cucumber genes involved in lipid mobilization and metabolism during cotyledon development to compare gene activity and to study the direction of carbon (acetyl unit) transport between glyoxysomes and mitochondria. The core metabolic pathway involving 10 genes was examined in four intracellular compartments: glyoxysomes (peroxisomes), mitochondria, chloroplasts, and cytosol. Additionally, we tested the early germination response of dark-grown seedlings and the immediate light response for a further 3 days. According to the reverse transcription polymerase chain reaction (RT-PCR), 3-L-ketoacyl-CoA thiolase 2 (Thio2), isocitrate lyase (ICL), and malate synthase (MS), the genes involved in storage lipid mobilization showed a similar and consistent pattern of gene expression in seedling development. Furthermore, coordinate expression of the A BOUT DE SOUFFLE (BOU) gene with ICL and MS during seedling emergence pointed to a possible secondary route of acetyl unit (acetyl-CoA) transport between peroxisomes and mitochondria in cucumber. The expression of the BOU gene was light dependent, as shown by BOU activity in Arabidopsis, suggesting that the dark condition also results in weak membrane biogenesis. In addition, several genes were active throughout the development of the green cotyledon, even during senescence. In conclusion, this study summarizes oil-seed germination and gene expression during cucumber cotyledon development and proposes an additional route for acetyl unit transport.