Unlocking fungal quorum sensing: Oxylipins and yeast interactions enhance secondary metabolism in monascus

Abstract

Exploring the symbiotic potential between fungal and yeast species, this study investigates the co-cultivation dynamics of Monascus, a prolific producer of pharmacologically relevant secondary metabolites, and Wickerhamomyce anomalous. The collaborative interaction between these microorganisms catalyzed a substantial elevation in the biosynthesis of secondary metabolites, prominently Monacolin K and natural pigments. Central to our discoveries was the identification and enhanced production of oxylipins (13S-hydroxyoctadecadienoic acid，13S-HODE), putative quorum-sensing molecules, within the co-culture environment. Augmentation with exogenous oxylipins not only boosted Monacolin K production by over half but also mirrored morphological adaptations in Monascus, affecting both spores and mycelial structures. This augmentation was paralleled by a significant upregulation in the transcriptional activity of genes integral to the Monacolin K biosynthetic pathway, as well as genes implicated in pigment and spore formation. Through elucidating the interconnected roles of quorum sensing, G-protein-coupled receptors, and the G-protein-mediate signaling pathway, this study provides a comprehensive view of the molecular underpinnings facilitating these metabolic enhancements. Collectively, our findings illuminate the profound influence of Wickerhamomyces anomalous co-culture on Monascus purpureus, advocating for oxylipins as a pivotal quorum-sensing mechanism driving the observed symbiotic benefits.

Keywords: Monascus purpureus; Oxylipins; Quorum sensing; Secondary metabolites; Wickerhamomyces anomalous.

Graphical abstract

Fig. 1

Effects of different concentrations of W.nomalus C22 on M. purpureus M1 pigment and MK.(A) Red pigment. (B) Orange pigment. (C) Yellow pigment. (D) MK content. Data are expressed as the mean ± SD (n = 3). *p < 0.05 and **p < 0.01, compared to the control. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)

Fig. 2

Effects of different densities of W.omalus C22 on the expression of M. purpureus M1 biosynthetic pigment and MK and spore-forming genes. (A–I) mokA-mokI gene expression level. (J–K) Expression level of Monascus pigment gene. (L–O). Expression levels of morphology-related genes in Monascus spore. *p < 0.05, **p < 0.01, compared with control group. Data are expressed as mean ± SD (n = 3).

Fig. 3

Determination of 13S-HODE in co‐culture M. purpureus M1 and W.nomalus C22 system. (A) TIC of Monascus by HPLC-MS. (B) HPLC-MS analysis of the daughter ions of oxylipin 13S-HODE. (C) HPLC-MS analysis of the parent ion of oxylipin 13S-HODE. *p < 0.05, and **p < 0.01, compared to the control. Data are expressed as the mean ± SD (n = 3).

Fig. 4

Effect of Exogenous Oxylipin on Monascus. (A) Oxylipin 13S-HODE content in control and co‐culture samples (3, 5, 7, 11, and 13 days).(B–C) Effects of different concentrations of 13S-HODE on M. purpureus MK and Gene expression levels. Effects of 13S-HODE on M. purpureus pigment. (D) Red pigment. (E) Orange pigment. (F) Yellow pigment. Data are expressed as the mean ± SD (n = 3). *p < 0.05 and **p < 0.01, compared to the control. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)

Fig. 5

Morphological changes of M. purpureus M1 after being cultured by co-culture and exogenous addition of 13S-HODE. (A)Morphology of M. purpureus M1 at × 100 magnifications by optical microscopy. (B) Morphology of co‐cultured M. purpureus M1 and W.anomalus C22 at 100 magnifications by optical microscopy. (C) Morphology of M. purpureus M1 with 13S-HODE added at × 100 magnification by optical microscopy. Solid red arrows point to monascus spores, hollow arrows point to yeast, and red circles represent conidia. (D) Scanning electron microscope images of the M. purpureus M1 mycelium and spore at 5000 × ,10,000 × . (E) Scanning electron microscope images of the co‐cultured M. purpureus M1 and W.anomalus C22 mycelium and spore at 5000 × ,10,000 × . (F) Scanning electron microscope images of the M. purpureus M1 with 13S-HODE added mycelium and spore at 5000 × ,10,000 × . (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)

Fig. 6

Co-culture with W. nomalus C22 and exogenous addition of oxylipins to cAMP signaling pathway and phosphatidyl inositol pathway of cAMP, PKA, PKC, and PLC. (A–D) Co-culture with W. nomalus C22. (E–H) Exogenous addition of oxylipins. *p < 0.05, **p < 0.01, compared with control group. Data are expressed as mean ± SD (n = 3).

Fig. 7

The result model of the interaction of W. anomalus and M. purpureus co-culture by quorum induction.