Project description:Candida glabrata is a human-associated opportunistic fungal pathogen. It shares its niche with Lactobacillus spp. in the gastrointestinal and vaginal tract. In fact, Lactobacillus species are thought to competitively prevent Candida overgrowth. We investigated the molecular aspects of this antifungal effect by analyzing the interaction of C. glabrata strains with Limosilactobacillus fermentum. From a collection of clinical C. glabrata isolates, we identified strains with different sensitivities to L. fermentum in coculture. We analyzed the variation of their expression pattern to isolate the specific response to L. fermentum. C. glabrata-L. fermentum coculture induced genes associated with ergosterol biosynthesis, weak acid stress, and drug/chemical stress. L. fermentum coculture depleted C. glabrata ergosterol. The reduction of ergosterol was dependent on the Lactobacillus species, even in coculture with different Candida species. We found a similar ergosterol-depleting effect with other lactobacillus strains (Lactobacillus crispatus and Lactobacillus rhamosus) on Candida albicans, Candida tropicalis, and Candida krusei. The addition of ergosterol improved C. glabrata growth in the coculture. Blocking ergosterol synthesis with fluconazole increased the susceptibility against L. fermentum, which was again mitigated by the addition of ergosterol. In accordance, a C. glabrata Derg11 mutant, defective in ergosterol biosynthesis, was highly sensitive to L. fermentum. In conclusion, our analysis indicates an unexpected direct function of ergosterol for C. glabrata proliferation in coculture with L. fermentum.
Project description:Paper mulberry as a valuable woody species has a well chilling tolerance. In this study, phosphoproteomic analysis in combination with physiological measurement and mRNA quantification were employed to explore the molecular mechanism of chilling (4 °C) tolerance in paper mulberry. After chilling for 6 hours, there were 427 significant changed phosphoproteins detected in paper mulberry seedlings without obvious physiological injury. When obvious physiological injury occurred after chilling for 48 hours, a total of 611 phosphoproteins were found significantly change at phosphorylation level. According to 9 phosphorylation motifs extracted by Motif-X analysis, MAPKs, CDPKs, CDKs and CKs were considered as the primary upstream protein kinases. Results of GO analysis showed that phosphoproteins were mainly responsible for signal transduction, protein modification and translation during chilling. Additionally, transport and cellular component organization were respectively enriched after chilling for 6 and 48 hours. Based on the analysis of protein-protein interaction network, a protein kinases and phosphatases hub protein was thought as the key of phosphorylation regulation, which probably modulates cross-talk between Ca2+, BR, ABA and ethylene mediated signaling pathways. Together with results, we concluded a schematic chilling tolerance mechanism at phosphorylation level.