INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2025
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IF 8.5
Feiyun Liu,Lingyan Guo,Yiqing Luo,Jingyi Li,Yao Zhou,Jing Wang,Xiaofei Huang,Xinyu Tan,Mingxin Fu,Bingzi Yu,Yan Gao,Renning Liu,Naoki Takaya,Shengmin Zhou
Ap-1-like transcription factors play a crucial role in regulating antioxidant gene expression and protecting cells from oxidative stress. Extensive research on redox regulation in Saccharomyces cerevisiae and Schizosaccharomyces pombe has revealed notable differences in their mechanisms. However, it remains unclear whether filamentous fungi share similarities with either yeast system or employ a distinct signaling strategy. To address this, we investigated the redox signal relay in Aspergillus nidulans , focusing on how peroxiredoxin PrxA and thioredoxin TrxA modulate the activity of the Ap-1-like transcription factor NapA. We demonstrate that PrxA is essential for NapA activation, transmitting the H₂O₂ signal through a disulfide bond between its peroxidatic and resolving cysteines to NapA's Cys558, which subsequently forms an intramolecular disulfide bond with Cys404. Furthermore, we reveal that TrxA, rather than Txl1, is responsible for reducing and inactivating NapA by direct interaction in both the cytoplasm and nucleus, utilizing its own catalytic cysteine residues. These findings establish a mechanistic framework for NapA activation and reduction, providing new insights into oxidative stress responses in filamentous fungi and their divergence from yeast systems.
研究领域:
分子生物学
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真菌学
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细胞信号传导
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DOI
PubMed
高影响因子
Microbiology Spectrum
·
2021
·Vol. 9
·期 3
·
IF 7.171
Alia Rizvi Syeda Kazim,Yuting Jiang,Shengnan Li,Xiaoxiao He
α-Glucan is a major cell wall component and a virulence and adhesion factor for fungal cells. However, the biosynthetic pathway of α-glucan was still unclear. α-Glucan was shown to be composed mainly of 1,3-glycosidically linked glucose, with trace amounts of 1,4-glycosidically linked glucose. Besides the α-glucan synthetases, amylase-like proteins were also important for α-glucan synthesis. In our previous work, we showed that Aspergillus nidulans AmyG was an intracellular protein and was crucial for the proper formation of α-glucan. In the present study, we expressed and purified AmyG in an Escherichia coli system. Enzymatic characterization found that AmyG mainly functioned as an α-amylase that degraded starch into maltose. AmyG also showed weak glucanotransferase activity. Most intriguingly, supplementation with maltose in shaken liquid medium could restore the α-glucan content and the phenotypic defect of a ΔamyG strain. These data suggested that AmyG functions mainly as an intracellular α-amylase to provide maltose during α-glucan synthesis in A. nidulans.IMPORTANCE Short α-1,4-glucan was suggested as the primer structure for α-glucan synthesis. However, the exact structure and its source remain elusive. AmyG was essential to promote α-glucan synthesis and had a major impact on the structure of α-glucan in the cell wall. Data presented here revealed that AmyG belongs to the GH13_5 family and showed strong amylase function, digesting starch into maltose. Supplementation with maltose efficiently rescued the phenotypic defect and α-glucan deficiency in an ΔamyG strain but not in an ΔagsB strain. These results provide the first piece of evidence for the primer structure of α-glucan in fungal cells, although it might be specific to A. nidulans.
研究领域:
微生物学
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分子生物学
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真菌遗传学
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细胞壁生物学
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产品关联
DOI
PubMed
高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2021
·Vol. 105
·期 16
·6333-6343
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IF 4.813
Wang Wei,An Chunyan,Yao Yongpeng,Meng Xiangxi,Gao Shu-Shan
The industrially important meta -cresol ( m -cresol, 3-methylphenol) is mainly produced from fossil resources by chemical methods. The microbial production of m -cresol was rarely investigated. Herein, we constructed a platform for the overproduction of m -cresol in a modified fungus Aspergillus nidulans FGSC no. A1145 ∆ST∆EM , which gave a gram-level titer using starch as carbon resource. For the biosynthesis of m -cresol, the 6-methyl salicylic acid synthase (MSAS)-encoding gene patK and 6-methyl salicylic acid decarboxylase-encoding gene patG from A. clavatus were co-expressed in the host A. nidulans . Multiple strategies, including promotor engineering, gene multiplication, and fed-batch fermentation, were applied to raise the production of m -cresol, which resulted in the titers of 1.29 g/L in shaking flasks and 2.03 g/L in fed-batch culture. The chassis cell A. nidulans A1145 ∆ST∆EM was proved to possess better tolerance to m -cresol than yeast, as it could grow in the liquid medium containing up to 2.5 g/L of m -cresol. These results showed that A. nidulans has great potential to be further engineered for industrial production of m -cresol.
Key points
• m-Cresol was de novo biosynthesized by a fungal chassis cell Aspergillus nidulans.
• Promoter engineering and gene multiplication implemented the fine-tuned genes expression.
• The titer of m-cresol reached 2.03 g/L via fed-batch culture.
Graphical abstract
研究领域:
生物技术
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微生物工程
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代谢工程
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yuan Tian,Qing Xu,Ning Wang,Yanling Li,Wenyu Yang,Fei Huang,Qing Hao,Liping Zhao,Zhiruo Zhang,Fengchun Zhao,Fanglong Zhao
The intricate regulatory networks in filamentous fungi severely constrain the production of high-value natural products. Here, we developed an efficient CRISPR-dCas9-SunTag activation system to overcome transcriptional repression in Aspergillus nidulans . Through systematic optimization of GCN4 repeat numbers and implementation of P2A-mediated dCas9-SunTag/GCN4-VP64 tandem expression, this platform showed 20-fold higher activation efficiency compared to dCas9-VPR system. When deployed to regulate the emodin biosynthetic pathway, multiplexed sgRNA targeting enabled coordinated upregulation of three key biosynthetic genes mdpF , mdpG , and mdpH . This precise regulation approach minimized byproduct accumulation while boosting emodin titer to 101 mg/L, achieving 71 % higher production than the natural transcription factor overexpression. Furthermore, this optimized CRISPRa system demonstrated consistent stability during liquid fermentation in 1 L bioreactors (emodin 1.3 g/L) and solid-state fermentation (emodin 1.5 mg/g cell dry weight), highlighting its potential for scalable fungal metabolic engineering. This study establishes a modular and precise genetic toolkit for reprogramming fungal secondary metabolism, offering broad potential for the engineered biosynthesis of high-value compounds.
研究领域:
分子生物学
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基因工程
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合成生物学
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真菌生物技术
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天然产物生物合成
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）