S‑Adenosylmethionine-Dependent Methyltransferase Helps Pichia caribbica Degrade Patulin

Patulin contamination not only is
a menace to human health but
also causes serious environmental problems worldwide due to the synthetic
fungicides that are used to control it. This study focused on investigating
the patulin degradation mechanism in Pichia caribbica at the molecular level. According to the results, P. caribbica (2 × 106 cells/mL) was
able to degrade patulin from 20 μg/mL to an undetectable level
in 72 h. The RNA-seq data showed patulin-induced oxidative stress
and responses in P. caribbica. The
deletion of PcCRG1 led to a significant decrease
in patulin degradation by P. caribbica, whereas the overexpression of PcCRG1 accelerated
the degradation of patulin. The study identified that PcCRG1 protein
had the ability to degrade patulin in vitro. Overall, we demonstrated
that the patulin degradation process in P. caribbica was more than one way; PcCRG1 was an S-adenosylmethionine-dependent
methyltransferase and played an important role in the patulin degradation
process in P. caribbica.

展青霉素（Patulin）污染不仅对人类健康构成威胁，同时由于用于防控该毒素的合成杀菌剂在全球范围内引发了严重的环境问题。本研究聚焦于在分子层面解析卡里比克毕赤酵母（Pichia caribbica）降解展青霉素的机制。研究结果显示，浓度为2×10^6个细胞/毫升的卡里比克毕赤酵母可在72小时内将初始浓度为20 μg/mL的展青霉素降解至无法检出水平。RNA测序（RNA-seq）数据表明，展青霉素可诱导卡里比克毕赤酵母产生氧化应激并触发相应应答反应。敲除PcCRG1基因会显著降低卡里比克毕赤酵母对展青霉素的降解能力，而过表达PcCRG1则可加速展青霉素的降解过程。本研究证实，PcCRG1蛋白在体外具备降解展青霉素的能力。综上，本研究证明卡里比克毕赤酵母降解展青霉素的过程并非单一途径；PcCRG1属于S-腺苷甲硫氨酸依赖性甲基转移酶，在卡里比克毕赤酵母降解展青霉素的过程中发挥了重要作用。