Pectin-rich biomass, derived from fruit and citrus processing waste, presents a promising yet underutilized resource for sustainable biofuel and biochemical production. Its low lignin content and high concentrations of fermentable sugars, including D-galacturonic acid, L-arabinose, and D-xylose, make it an attractive feedstock. Unlike lignocellulosic biomass, pectin-rich hydrolysates require milder pretreatment, improving sugar recovery efficiency. However, industrial strains such as Saccharomyces cerevisiae exhibit strong glucose preference, limiting the efficient co-fermentation of mixed sugars. While prior reviews have broadly addressed lignocellulosic biomass utilization, this mini-review uniquely centers on the specific metabolic challenges and opportunities associated with pectin-rich feedstocks. In addition to incorporating established strategies for the co-utilization of cellobiose and xylose, we highlight recent advances that allow S. cerevisiae to metabolize carbon sources specifically from pectin-rich biomass, such as L-arabinose and D-galacturonic acid—monomers not prevalent in traditional lignocellulosic biomass. By integrating discussions on sugar transport engineering, redox balancing, and pathway optimization, this review offers a comprehensive framework to overcome glucose repression and support efficient co-fermentation of carbon sources from conventional and pectin-rich biomass. Drawing on these advances, we outline practical strategies to enhance fermentation performance and expand the valorization of food processing residues in biomanufacturing.

Condensin plays a central role in mitotic chromosome organization and segregation by mediating long-range chromatin interactions. However, the extent to which cellular metabolic status influences condensin function remains unclear. To gain insights into the relationship of metal ion homeostasis and the function of condensin, we conducted genome-wide chromatin immunoprecipitation sequencing (ChIP-seq) using Schizosaccharomyces pombe under iron- or zinc-deficient conditions. Under iron- or zinc-deficient conditions, ChIP-seq results revealed a selective reduction in condensin binding at high-affinity target loci, particularly genes regulated by Ace2 and Ams2, while cohesin binding remained largely unaffected. Hi-C analysis showed that iron depletion weakened chromatin interactions at these condensin targets and centromeres, without disrupting global genome architecture. DNA fluorescence in situ hybridization (FISH) confirmed that iron deficiency impaired long-range associations between centromeres and Ace2 target loci at the single-cell level. Notably, iron deficiency led to chromosome segregation defects during mitosis, suggesting that diminished condensin occupancy compromised genome stability. These changes occurred without significant alterations in condensin protein levels or global transcription, indicating a direct effect of metal ion availability on condensin activity. Collectively, our findings revealed a previously unrecognized regulatory axis in which cellular metal ion homeostasis modulated condensin-dependent chromatin organization and mitotic chromosome segregation, offering new insights into the integration of metabolic state with genome maintenance.

The oral administration of synthetic drugs can effectively reduce blood lipid levels, but adverse reactions may occur. Because of this, the hypolipidemic ability of natural products has been increasingly investigated. We evaluate the safety and hypolipidemic characteristics of a water-soluble blue pigment extracted using HPD-400 resin from the fungus Quambalaria cyanescens. Hypolipidemic ability was examined by constructing a hyperlipidemia model with different doses of blue pigment (50, 100, and 200 mg/kg. mouse body weight) for 28 d. Blue pigment purity increased from 20.32% to 70.70% following treatment with HPD-400 resin. Acute toxicity tests revealed blue pigment sourced from Q. cyanescens to have no toxic effects on mouse body weight, mortality, or behavioral characteristics. Subacute toxicity tests revealed no significant differences in food intake, body weight, or organ weights between treatment groups and controls. Histopathological examination of the liver and kidney tissues of mice administered blue pigment were normal, and serum enzyme activities and blood constituents were also within normal ranges. Blue pigment can significantly reduce the weight of mice, reduce liver and kidney damage and fat accumulation. It can also reduce total cholesterol, triglyceride and low density lipoprotein cholesterol in serum and liver tissue, and increase the level of high density lipoprotein cholesterol. Reduce the levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, creatinine, urea and uric acid in serum. Increase the activities of total superoxide dismutase, glutathione peroxidase and catalase in serum and liver tissue, reduce the content of malondialdehyde, and up-regulate liver lipase and lipoprotein lipase. Our work proves that blue pigment is nontoxic, has the function of reducing blood lipid, and can alleviate obesity-related symptoms by regulating lipid metabolism and oxidative stress.

Opportunistic fungal pathogens, responsible for over 300 million severe cases and 1.5 million deaths annually, pose a serious global health threat, especially in immunocompromised individuals. Among these, Candida albicans is a major cause of both superficial and invasive infections, which can progress to systemic candidiasis. One of the critical factors in C. albicans pathogenicity is the yeast-to-hyphal transition, which enables biofilm formation and promotes tissue invasion through the secretion of candidalysin, a cytolytic peptide toxin encoded by the ECE1 gene. In this study, metabolites produced by Streptomyces ambofaciens CJD34, isolated from soil samples, were screened for antifungal activity. Methoxy-apo-enterobactin (compound 1) was identified as a potential inhibitor of C. albicans virulence. Treatment with compound 1 significantly suppressed ECE1 expression and candidalysin production. In a murine subcutaneous infection model, topical application of compound 1 reduced subcutaneous colonization by C. albicans. Molecular docking analysis suggested that the inhibition of ECE1 expression was not mediated by direct binding to known upstream transcription factors, indicating an indirect mechanism of action. Collectively, these findings highlight compound 1 as a promising antivirulence agent targeting candidalysin-mediated pathogenicity in C. albicans.

Yeast prion [PSI+], an amyloid form of the translation termination factor Sup35p/eRF3, causes translational stop codon readthrough by sequestering functional Sup35p. This unique phenotype may be analyzed via [PSI+]−suppressible nonsense alleles, and has greatly contributed to the advancement in yeast prion research. For comparing canonical reporters, like chromosomal ade1−14 or ade2−1, and plasmid-borne ura3−14, the de novo generation and characteristics of [PSI+] was investigated across common yeast laboratory strains (BY4741, 74D−694, and 779−6A). The results showed significant variability in [PSI+] induction frequency among strains. [PSI+] was successfully induced in BY4741 and frequently in 74D−694 (via Ade⁺ selection), but not in 779−6A. Notably, [PSI+] clones, even from identical genetic backgrounds, displayed vastly different nonsense suppression phenotypes depending on the reporter allele used; resulting in diverse growth patterns and suppression levels. Quantitative analyses revealed that prion seed counts fluctuated significantly based on the detection allele and observed phenotype. Furthermore, Sup35p aggregate visualization revealed distinct structural patterns between BY4741 and 74D−694, indicating strain-specific differences. Transferring [PIN+] prion variants from different strains into a common [psi−][pin−] background yielded similar [PSI+] inducibility and seed numbers, suggesting that the observed phenotypic and quantitative diversities of [PSI+] prions stem primarily from the interplay between the specific reporter detection system and the host strain's genetic background rather than solely from inherent differences in the initial [PIN+] prion or fundamental changes in the [PSI+] protein itself. This study underscores the crucial need to consider both the detection methodology and host genetic context for accurate prion variant characterization.

Candida albicans (C. albicans) is a common opportunistic fungal pathogen that can cause infections ranging from superficial to severe systemic diseases. This study investigates the antifungal effects of metformin on C. albicans and explores its underlying mechanisms. Growth inhibition was assessed via XTT assays, and hyphal formation and morphological changes were observed by light microscope and scanning electron microscopy (SEM). Mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) levels were measured with JC-1 and DCFH-DA probes, respectively. Gene expression related to ROS and autophagy was quantified by RT-qPCR, and autophagosomes were visualized using transmission electron microscopy (TEM). Metformin significantly inhibited C. albicans growth and hyphal formation, altered cell morphology, reduced MMP, and increased ROS levels. It activated autophagy in planktonic C. albicans but suppressed it in biofilm forms. Additionally, metformin exhibited synergistic effects with amphotericin B against planktonic C. albicans and with caspofungin against biofilms. The findings suggest that metformin exerts antifungal activity by modulating MMP, ROS levels, and autophagy-related pathways, and enhances the efficacy of specific antifungal drugs.

Akkermansia muciniphila (AKK, A. muciniphila) fortifies the intestinal barrier, inhibits the colonization of pathogenic bacteria, and protects the host’s health. Nevertheless, the existing literature offers inadequate evidence to ascertain whether A. muciniphila can effectively treat Candida albicans (C. albicans) infections in vitro, and the underlying mechanisms remain ambiguous. This study, animal models were established through gavage with clinical isolates of C. albicans to induce gastrointestinal tract colonization and subsequent translocation infection. The models were subsequently administered A. muciniphila. We examined the analysis of 16S rRNA gene sequencing, metabolomics of colonic contents, and transcriptomics of colonic tissue. The intestinal barrier, inflammatory responses, and immune cell infiltration are analyzed. This study revealed that A. muciniphila markedly mitigated C. albicans translocation infection and modified the intestinal microbial community structure and metabolic attributes in model mice. After administering A. muciniphila to the translocation infection group, there was a notable increase in the prevalence of bacteria that produce short-chain fatty acids, including Eubacterium_F. Moreover, there was a significant increase in the levels of specific pathogens, including Faecalibaculum, Turicibacter, and Turicimonas. The study demonstrated that A. muciniphila treatment can improve the composition of intestinal microbiota and metabolites, augment the tight junctions of colonic tissue and diminish systemic inflammatory response. This presents an innovative therapeutic approach for the potential treatment of intestinal C. albicans infection using A. muciniphila.

A thermophilic strain of Paecilomyces variotii (MR1), capable of surviving temperatures above 40°C, was isolated from a paper mill and investigated as a host for heterologous protein production. To prevent environmental dissemination of spores, UV mutagenesis was employed to create a conidia-deficient strain, UM7. This strain underwent gene editing using Cas9-gRNA ribonucleoprotein (RNP) with HR donor DNA fragments, incorporating promoter sequences amplified from the genomic DNA of P. variotii (P_H4, P_P2, P_S8, P_tub, P_tef1, and P_gpdA), along with a signal sequence-tagged eGFP, flanked by 5’-upstream (336 bp) and 3’-downstream (363 bp) regions of pyrG. Co-transformation of HR donor DNA with RNP into protoplasts yielded 48 mutant pyrG transformants capable of surviving in the presence of 5-fluoroorotic acid (5-FOA). Sequence analysis identified 16 of the 48 pyrG-disrupted mutants carrying complete HR donor DNAs with the six different promoter sequences, indicating successful homology-directed repair (HDR). Evaluation of promoter strength revealed that P_gpdA was the most effective for intracellular GFP production; however, it resulted in negligible extracellular GFP signal under all promoter conditions. A newly edited strain with an HDR integration module connecting P_gpdA directly to eGFP, without the signal sequence, exhibited enhanced GFP expression in both mycelial cells and culture broth, suggesting that the signal peptide negatively affect protein expression and secretion. This work represents the first successful RNP-mediated gene editing in P. variotii, contributing to the application of this thermophilic fungus in protein production.

Microbial biosynthesis using yeast species offers numerous advantages to produce industrially relevant biofuels and biochemicals. Conventional metabolic engineering approaches in yeast focus on biosynthetic pathways in the cytoplasm, but these approaches are disturbed by various undesired factors including metabolic crosstalk, competing pathways and insufficient precursors. Given that eukaryotic cells contain subcellular organelles with distinct physicochemical properties, an emerging strategy to overcome cytosolic pathway engineering bottlenecks is through repurposing these organelles as specialized microbial cell factories for enhanced production of valuable chemicals. Here, we review recent progress and significant outcomes of harnessing organelle engineering for biofuels and biochemicals production in both conventional and non-conventional yeasts. We highlight key engineering strategies for the compartmentalization of biosynthetic pathways within specific organelles such as mitochondria, peroxisomes, and endoplasmic reticulum; involved in engineering of signal peptide, cofactor and energy enhancement, organelle biogenesis and dual subcellular engineering. Finally, we discuss the potential and challenges of organelle engineering for future studies and propose an automated pipeline to fully exploit this approach.

The increasing environmental concerns regarding conventional plastics have led to a growing demand for sustainable alternatives, such as biodegradable plastics. Yeast cell factories, specifically Saccharomyces cerevisiae and Yarrowia lipolytica, have emerged as promising platforms for bioplastic production due to their scalability, robustness, and ease of manipulation. This review highlights synthetic biology approaches aimed at developing yeast cell factories to produce key biodegradable plastics, including polylactic acid (PLA), polyhydroxyalkanoates (PHAs), and poly (butylene adipate-co-terephthalate) (PBAT). We explore recent advancements in engineered yeast strains that utilize various synthetic biology strategies, such as the incorporation of new genetic elements at the gene, pathway, and cellular system levels. The combined efforts of metabolic engineering, protein engineering, and adaptive evolution have enhanced strain efficiency and maximized product yields. Additionally, this review addresses the importance of integrating computational tools and machine learning into the Design-Build-Test-Learn cycle for strain development. This integration aims to facilitate strain development while minimizing effort and maximizing performance. However, challenges remain in improving strain robustness and scaling up industrial production processes. By combining advanced synthetic biology techniques with computational approaches, yeast cell factories hold significant potential for the sustainable and scalable production of bioplastics, thus contributing to a greener bioeconomy.