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.