单羧酸转运蛋白MpMch2调控紫色红曲霉的性发育及代谢产物的产生

Monocarboxylate transporter MpMch2 regulates the sexual development and metabolite production of Monascus purpureus

摘要:

乳酸、丙酮酸、酮体等单羧酸盐在生物体的代谢活动中发挥重要作用。MpMch2作为单羧酸转运蛋白，主要负责单羧酸盐的跨膜转运，维持葡萄糖代谢平衡等。【目的】在紫色红曲霉中对单羧酸转运蛋白MpMch2进行功能分析。【方法】以紫色红曲霉Mp-21为出发菌株，通过构建敲除载体，利用同源重组的方式将潮霉素基因替换MpMch2得到缺失株∆MpMch2。观察Mp-21和∆MpMch2在不同培养基上菌落形态、显微形态，测定其红曲色素、γ-氨基丁酸产量、分生孢子、子囊孢子产量等；利用RT-qPCR检测分生孢子、γ-氨基酸丁酸相关基因表达量。【结果】在不同培养基上野生型和∆MpMch2在菌落形态上无显著差异，该基因敲除后菌株分生孢子、子囊孢子产量下降，红曲色素、γ-氨基丁酸产量及相关基因表达量下降。【结论】表明MpMch2基因正调控分生孢子和子囊孢子发育及红曲色素、γ-氨基丁酸产量。

Abstract:

Monocarboxylates such as lactate, pyruvate, and ketone bodies play an important role in the metabolic activities of organisms. As a monocarboxylate transporter, MpMch2 is mainly responsible for the transmembrane transport of monocarboxylates and the maintenance of glucose metabolism balance. [Objective] To analyze the functions of MpMch2 in Monascus purpureus. [Methods] The MpMch2 in M. purpureus Mp-21 was replaced with the hygromycin gene by homologous recombination to construct the deletion strain ∆MpMch2. The colony and cell morphology of Mp-21 and ∆MpMch2 on different media was observed, and the yield of monascus pigment, γ-aminobutyric acid, conidia and ascospores were determined. The expression levels of genes related to conidia and γ-aminobutyric acid were determined by RT-qPCR. [Results] There was no significant difference in the colony morphology between the wild type and ∆MpMch2 on different media. After knockout of MpMch2, the yields of conidia, ascospores, Monascus pigments, and γ-aminobutyric acid decreased, and the expression levels of related genes were down-regulated. [Conclusion] MpMch2 positively regulated the development of conidia and ascospores and the production of Monascus pigments and γ-aminobutyric acid.