In this study, we employed a combination of genome mining and heteronuclear single quantum coherence (HSQC)-based small molecule accurate recognition technology (SMART) technology to search for fernane-type triterpenoids. Initially, potential endophytic fungi were identified through genome mining. Subsequently, fine fractions containing various fernane-type triterpenoids were selected using HSQC data collection and SMART prediction. These triterpenoids were then obtained through targeted isolation and identification. Finally, their antifungal activity was evaluated. As a result, three fernane-type triterpenoids, including two novel compounds, along with two new sesquiterpenes and four known compounds were isolated from one potential strain, Diaporthe discoidispora. Their structures were elucidated through analysis of high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) and nuclear magnetic resonance (NMR) spectroscopic data. The absolute configurations were determined using single-crystal X-ray diffraction analysis and electron capture detector (ECD) analysis. Compound 3 exhibited moderate antifungal activity against Candida albicans CMCC 98001 and Aspergillus niger.
Triterpenes/isolation & purification* ; Antifungal Agents/isolation & purification* ; Molecular Structure ; Candida albicans/drug effects* ; Ascomycota/genetics* ; Magnetic Resonance Spectroscopy ; Aspergillus niger/drug effects* ; Genome, Fungal ; Microbial Sensitivity Tests

(±)-Talapyrones A-F (1-6), six pairs of dimeric polyketide enantiomers featuring unusual 6/6/6 and 6/6/6/5 ring systems, were isolated from the fungus Talaromyces adpressus. Their structures were determined by spectroscopic analysis and HR-ESI-MS data, and their absolute configurations were elucidated using a modified Mosher's method and electronic circular dichroism (ECD) calculations. (±)-Talapyrones A-F (1-6) possess a 6/6/6 tricyclic skeleton, presumably formed through a Michael addition reaction between one molecule of α-pyrone derivative and one molecule of C₈ poly-β-keto chain. In addition, compounds 2/3 and 4/5 are two pairs of C-18 epimers, respectively. Putative biosynthetic pathways of 1-6 were discussed.
Polyketides/isolation & purification* ; Talaromyces/chemistry* ; Stereoisomerism ; Molecular Structure ; Circular Dichroism ; Pyrones/chemistry*

This study identified six novel azaphilones, isochromophilones G-L (1-6), and three novel biosynthetically related congeners (7-9) from Diaporthe sp. SCSIO 41011. The structures and absolute configurations were elucidated through comprehensive spectroscopic analyses combined with experimental and calculated electronic circular dichroism (ECD) spectra. Significantly, three highly oxygenated azaphilones contain an acetyl group at the terminal chain (4) or linear conjugated polyenoid moieties (5 and 6), which occur infrequently in the azaphilone family. Additionally, several compounds demonstrated inhibition of lipopolysaccharide (LPS)-induced nuclear factor kappa-B (NF-κB) activation in RAW 264.7 macrophages at 20 μmol·L^-1. The novel compound (1) effectively inhibited receptor activator of NF-κB ligand (RANKL)-induced osteoclast differentiation without exhibiting cytotoxicity in bone marrow and RAW 264.7 macrophages, indicating its potential as a promising lead compound for osteolytic disease treatment. This research presents the first documented evidence of azaphilone derivatives as inhibitors of RANKL-induced osteoclastogenesis.
Animals ; Mice ; RANK Ligand/genetics* ; RAW 264.7 Cells ; Osteoclasts/metabolism* ; Benzopyrans/isolation & purification* ; Osteogenesis/drug effects* ; Macrophages/metabolism* ; Molecular Structure ; Pigments, Biological/isolation & purification* ; Ascomycota/chemistry* ; NF-kappa B/genetics* ; Cell Differentiation/drug effects*

Transcriptional regulation based on transcription factors is an effective regulatory method widely used in microbial cell factories. Currently, few naturally transcriptional regulatory elements have been discovered from Saccharomyces cerevisiae and applied. Moreover, the discovered elements cannot meet the demand for specific metabolic regulation of exogenous compounds due to the high background expression or narrow dynamic ranges. There are abundant transcriptional regulatory elements in plants. However, the sequences and functions of most elements have not been fully characterized and optimized. Particularly, the applications of these elements in microbial cell factories are still in the infancy stage. In this study, natural regulatory elements from Medicago truncatula were selected, including the transcription factors MtTASR2 and MtTASR3, along with their associated promoter P_roHMGR1, for functional characterization and engineering modification. We constructed an inducible transcriptional regulation tool and applied it in the regulation of heterologous β-carotene synthesis in S. cerevisiae, which increased the β-carotene production by 7.31 folds compared with the original strain. This study demonstrates that plant-derived transcriptional regulatory elements can be used to regulate the expression of multiple genes in S. cerevisiae, providing new strategies and ideas for the specific regulation and application of these elements in microbial cell factories.
Medicago truncatula/metabolism* ; Saccharomyces cerevisiae/metabolism* ; Transcription Factors/genetics* ; beta Carotene/biosynthesis* ; Promoter Regions, Genetic/genetics* ; Gene Expression Regulation, Plant ; Metabolic Engineering/methods* ; Regulatory Elements, Transcriptional/genetics* ; Plant Proteins/genetics*

Wickerhamomyces ciferrii (W.c), an unconventional heterothallic yeast species, is renowned for its high production of tetraacetyl phytosphingosine (TAPS). Due to its excellent performance in TAPS production, this study aimed to construct a genetic operating system of W.c to enhance the production of TAPS and to screen high-yielding strains by mutagenesis and genetic engineering, thus laying the foundation for further development of industrial production of sphingolipid metabolites. In this study, we selected two autonomous replication elements (CEN, 2μ) and mined 11 endogenous promoter elements to establish a genetic operating system in W. ciferrii. The overexpression of Syr2 and Lcb2 in the sphingolipid metabolism pathway significantly increased the production of TAPS. Meanwhile, we established a method for the identification of haploid mating types of W. ciferrii by combining RT-PCR and flow cytometry. Five strains of W. ciferrii with different mating types constructed from the standard diploid W. ciferrii ATCC 14091 were screened out. A-type haploid W.c 140 showcased the highest production of TAPS with a yield of 4.74 mg/g and a titer of 32.61 mg/L. Mutant strains W.c 140-A9 and W.c 140-A11 were induced by atmospheric pressure room temperature plasma mutagenesis. The recombinant strains W.c 140 OELcb2 and W.c 140 OESyr2 with overexpression were constructed with the genetic operating system established in this study. The TAPS yields of the mutant strains increased by 61.39% and 67.09%, respectively, compared with that of starting strain W.c 140. The recombinant strains cultured in the LCBNB medium achieved yields of 10.60 mg/g and 12.14 mg/g, respectively, representing 2.24 and 2.56 times of that in strain W.c 140. Moreover, the yields of the two recombinant strains were significantly higher than that of the diploid strain ATCC 14091. The genetic operating system and the haploid strain W.c 140 established in this study provide a basis for the subsequent establishment of genetic engineering tools for W. ciferrii.
Sphingosine/genetics* ; Saccharomycetales/metabolism* ; Genetic Engineering/methods* ; Promoter Regions, Genetic ; Metabolic Engineering/methods* ; Fungal Proteins/genetics*

To prepare antibodies that specifically recognize the conserved domain in the large extracellular loop of the CD63 protein, we expressed anti-CD63 single-chain variable fragment (scFv) antibody in Pichia pastoris in a secreted form. The purified expression product was found to bind specifically with CD63 protein and recognize CD63 on the surface of SK-MEL-28 cells. The variable region of the anti-CD63 monoclonal antibody in an anti-CD63-positive cell line was sequenced. The anti-CD63 scFv consisted of a variable heavy chain and a variable light chain linked by a flexible peptide was then designed. After codon optimization, the gene was synthesized and cloned into the expression plasmid pPICZα-A. The SacI-linearized plasmid was electroporated into P. pastoris X33, and 1% methanol were used to induce the expression of scFv. The fermentation supernatant was purified by Ni column. Anti-CD63 scFv was identified by SDS-PAGE and Western blotting, and its biological activities were analyzed by immunoblotting, immunofluorescence, cell-based ELISA, and flow cytometry. A P. pastoris strain capable of expressing and secreting anti-CD63 scFv was successfully obtained. The antibody had a molecular weight of approximately 30 kDa and specifically recognized CD63 protein. The expression of anti-CD63 scFv in P. pastoris paves the way for the production of anti-CD63 antibodies on a large-scale, which is undoubtedly an economical and effective way of antibody acquisition.
Single-Chain Antibodies/immunology* ; Humans ; Tetraspanin 30/immunology* ; Recombinant Proteins/immunology* ; Pichia/genetics* ; Saccharomycetales/metabolism*

The enterotoxigenic Escherichia coli (ETEC) infection is a major factor restricting the development of animal husbandry. However, the abuse of antibiotics will lead to the antibiotic residues and emergence of antibiotic-resistant bacteria. The existing vaccines face challenges in stimulating intestinal immunity, demonstrating limited prevention effects. Therefore, it is indispensable to develop a new vaccine that is safe and suitable as a feed additive to activate intestinal immunity. This study constructed yeast-cell microcapsules (YCM) carrying the DNA vaccine against ETEC by genetic engineering. Furthermore, animal experiments were carried out to explore the regulatory effects of feeding YCM on the intestinal immune system and intestinal microbiota. Saccharomyces cerevisiae was selected as the oral delivery vehicle (microcapsules) of the DNA vaccine. The codon-optimized nucleic acid sequence of K88, the main antigen of mammal-derived ETEC, was synthesized, and the yeast shuttle vector containing the corresponding DNA vaccine expression cassette was constructed by DNA recombination. The recombinant strain of YCM was prepared by transforming JMY1. Additionally, the characteristics of the YCM strain and its feasibility as an oral vaccine were comprehensively evaluated by the fluorescence reporter assay, gastrointestinal fluid tolerance assay, intestinal epithelial cell adhesion assay, intestinal retention assessment, antiserum detection, and intestinal microbiota detection. The experimental results showed that the DNA vaccine expression cassette was expressed in mammals, and the recombinant strain of YCM could tolerate up to 8 hours of gastrointestinal fluid digestion and had good adhesion to intestinal epithelial cells. The results of mouse feeding experiments indicated that the recombinant strain of YCM could stay in the intestinal tract for at least two weeks, and the DNA vaccine expression cassette carried by YCM entered the intestinal immune system and triggered an immune response to induce the production of specific antibodies. Moreover, feeding YCM recombinant bacteria also improved the abundance of gut microbiota in mice, demonstrating a positive effect in regulating intestinal flora. In summary, we prepared the recombinant strain of YCM carrying the DNA vaccine against ETEC and comprehensively evaluated its characteristics and feasibility as an oral vaccine. Feeding the recombinant YCM could induce specific immune responses and regulate intestinal microbiota. The findings provide a reference for the immunoprevention of ETEC-related animal diseases.
Animals ; Enterotoxigenic Escherichia coli/genetics* ; Saccharomyces cerevisiae/metabolism* ; Vaccines, DNA/genetics* ; Mice ; Escherichia coli Infections/immunology* ; Escherichia coli Vaccines/genetics* ; Capsules ; Mice, Inbred BALB C ; Female

To construct stress-responsive promoters, we mined the transcriptome data of the industrial strain A223 under stress. The transcription factor CIN5 showed significantly increased expression under stress but exhibited limited resistance. Further analysis of CIN5-interacting genes revealed that the binding motif "TTACGTAATC" (named CIN5BS) of CIN5 displayed transcription-enhancing activity. Four artificially enhanced promoters TCIN5B(3-6) were created by insertion of CIN5BS as a cis-element into different sites of the promoter TEF1, achieving 15.25-fold transcriptional enhancement. Five cis-elements (CIN5B4-1-CIN5B4-5) were designed through G+C content optimization, generating five stronger artificially enhanced promoters (TCIN5B4-1-TCIN5B4-5). For example, TCIN5B4-1 demonstrated 4.71 times higher transcriptional activity than the control at 37 ℃. This study established a technical framework of transcription factor mining-cis-element design-promoter reconstruction, providing a reference strategy for yeast cell factories to stably produce natural compounds under high-temperature stress conditions.
Promoter Regions, Genetic/genetics* ; Transcription Factors/genetics* ; Saccharomyces cerevisiae/metabolism* ; Stress, Physiological/genetics* ; Saccharomyces cerevisiae Proteins/genetics*

Triterpenoids in cosmetic raw materials have attracted much attention due to their various skin-care effects such as anti-inflammatory, antioxidant, and moisturizing properties, showing broad application prospects. However, the conventional methods such as chemical synthesis and plant extraction for obtaining triterpenoid have problems like poor sustainability, which limit their application in large-scale production. In recent years, with the development of synthetic biology and metabolic engineering, yeast synthesis of compounds has provided a green and sustainable alternative for the production of triterpenoids. This article reviews the research progress in the synthesis of triterpenoids and their derivatives in the cosmetic field and elaborates on the two main synthesis pathways (mevalonate and methylerythritol phosphate pathways) and their advantages and limitations in different microbial hosts. In addition, this article introduces the current status of the synthesis of triterpenoids and their derivatives in yeast, discusses the current strategies for increasing the yield, and looks ahead to the future development directions, aiming to promote the applications of triterpenoids in the cosmetic field.
Triterpenes/metabolism* ; Cosmetics/chemistry* ; Metabolic Engineering/methods* ; Saccharomyces cerevisiae/genetics* ; Synthetic Biology

Sesquiterpenes are natural terpenes containing 15 carbon atoms. They are widely used in the perfume, pharmaceutical, and biofuel industries due to their remarkable biological activities. The traditional production of sesquiterpenes relies on chemical synthesis or plant extraction, which has the disadvantages of low yields and waste of resources. The construction of microbial cell factories for the efficient synthesis of sesquiterpenes by means of synthetic biology provides a new option. In recent years, with the development of metabolic engineering and synthetic biology, the heterologous synthesis of a variety of sesquiterpenes has been successfully achieved by metabolic engineering of the oleaginous yeast, Yarrowia lipolytica. In this paper, we review the research progress in the heterologous synthesis of different sesquiterpenes by Y. lipolytica, discuss the synthetic biology strategies commonly used in this field, and make an outlook on the research directions and engineering approaches to further enhance the sesquiterpene yield in this host. This paper provides a reference for strategies such as synergistic optimization of synthetic biology and metabolic engineering, enhanced precursors, and opens up new directions for the application of synthetic biology in green chemistry and sustainable production.
Yarrowia/genetics* ; Sesquiterpenes/metabolism* ; Metabolic Engineering/methods* ; Synthetic Biology/methods*