JOURNAL OF HAZARDOUS MATERIALS
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2025
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IF 11.3
Wenxue Jiang,Miao Wu,Zhou Gong,Linhua Han,Xiaoqi Cheng,Xiaoqin Tang,Xiaolong Yu,Xu Dong,Yibin Cheng,Lixin Ma,Qiong Xing
Industrial derived aromatic hydrocarbons are persistent environmental pollutants due to their chemical stability, posing both ecological and health risks. Rieske-type aromatic dioxygenases (RDOs), known for their role in dihydroxylation of aromatic rings, play a pivotal role in microbial consumption and degradation of such compounds. While the industrial application of these enzymes has been impeded by their instability and low biodegradation rate. In this study, we focused on optimization and application of the Rieske-type dioxygenase HcaEF from Escherichia coli ( E. coli ) K-12, which initializes the degradation of 3-phenylpropionic acid (3-PP) and cinnamic acid (CI). Using cryo-electron microscopy (cryo-EM), we determined the high-resolution structures of the apo-form and 3-PP bound form of HcaEF, revealing key insights into substrate specificity and thermal stability. Leveraging these structural insights, we engineered a Q73I variant of HcaEF. Upon introduction of this mutation, the turnover rate increased from 29.6% to 43.8%, showing ~50% improvement. Overexpression of this variant in E. coli K-12 significantly enhanced the strain’s ability to utilize 3-PP, demonstrating the potential for microbial engineering in environmental bioremediation and industrial applications. Our findings not only deepen the understanding of substrate recognition in RDOs, but also pave the way for developing high-efficiency enzymes for aromatic compound bio-utilization.
研究领域:
环境微生物学
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酶工程
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生物化学
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产品关联
DOI
PubMed
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
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2022
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IF 3.705
Hong-Ru Zhao,Bing-Mei Su,Yi-Bing Shi,Juan Lin
Ethyl 3-hydroxy-3-phenylpropionate (EHPP), ( R )-EHPP or ( S )-EHPP, is an important chiral intermediate for pharmaceuticals. Its synthesis from ethyl benzoyl acetate (EBA) by alcohol dehydrogenase is regarded as a green method. However, scarcely any alcohol dehydrogenase has been reported competent in asymmetric synthesis of chiral EHPP at high EBA loading. Present study developed two robust and efficient bio-catalysts Mu-S2 and Mu-R4 for preparation of ( S )-EHPP and ( R )-EHPP respectively by rational design of alcohol dehydrogenase PcSDR from Pedobacter chitinilyticus based on molecular dynamics (MD) simulation analysis. BtGDH, a glucose dehydrogenase from Bacillus toyonensis catalyzing the oxidation of glucose for cofactor regeneration, was co-expressed with the screened mutants to form enzyme systems Mu-S2-BtGDH and Mu-R4-BtGDH. After reaction condition optimization, Mu-S2-BtGDH and Mu-R4-BtGDH were efficient in the synthesis of ( S )-EHPP (94% conv. and 99% e.e.) and ( R )-EHPP (99% conv. and 98% e.e. ) respectively in 100 mL scale under 500 mM of EBA loading in 10 h following a substrate continuous feeding mode. After purifying, the isolated yield for each EHPP enantiomer is > 93%. This work not only provides potential biocatalysts for the industrial production of ( R )-EHPP and ( S )-EHPP, but also enriches the constructure-function relationship of alcohol dehydrogenases.
研究领域:
生物化学
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酶工程
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药物化学
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产品关联
DOI
PubMed
高影响因子
PHYTOMEDICINE
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2025
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IF 8.3
Linlin Ding,Qingjie Li,Kaige Qi,Yonghui Chen,Na Hu,Sangyu Hu,Tianqi Fang,Shuang Guan,Jianfeng Wang,Jiazhang Qiu,Xuming Deng,Lei Xu
Background Salmonella pullorum ( S. pullorum ) is an enteric pathogen that impairs growth performance, leading to substantial economic losses. Evidence demonstrates that the natural flavonoid phloretin can modulate intestinal microbiota functionality, and which underpins its therapeutic efficacy in ameliorating gastrointestinal disorders. However, the protective effects of phloretin against S. pullorum infections and underlying mechanisms remain unelucidated. Purpose This study aimed to elucidate the protective effects and mechanisms of phloretin in improving defense against S. pullorum infection by modulating gut microbiota in chicks. Methods H&E staining, RT-qPCR and ELISA assays were used to assess the protective potentials of phloretin in S. pullorum -infected chicks. Then, 16S rRNA gene sequencing and untargeted metabolomics were employed to identify key microbiota and metabolites regulating the intestinal microenvironment. Moreover, fecal microbiota transplantation (FMT) and dietary metabolite supplementation were conducted to reshape the gut microbiota, elucidate the interaction between the microbiota and S. pullorum infection. Results Phloretin treatment alleviated intestinal injury and enhanced growth performance in S. pullorum -infected chicks via improved intestinal barrier integrity, suppression of inflammatory responses, and restructuring of gut microbial composition. Additionally, these beneficial effects were also observed following FMT from phloretin-treated donors. Subsequent microbial and untargeted metabolomic analysis revealed that phloretin significantly enriched abundance of the functional bacterium Faecalibacterium , and the microbiota-derived phenylalanine metabolites 3-phenylpropionic acid (3-PPA). Importantly, 3-PPA supplementation attenuates S. pullorum -induced intestinal barrier damaged and inflammation in chicks through modulation of the AhR/IL-22/STAT-3 signalling axis. Conclusion These findings provide new insights into the therapeutic potentials of phloretin for S. pullorum -infected chicks.
研究领域:
微生物学
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免疫学
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分子生物学
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兽医学
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代谢组学
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药理学
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DOI
PubMed
高影响因子
Fungal Biology
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2023
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IF 2.5
Jiaxin Liu,Canying Li,Chenyang Zhang,Rui Huang,Linhong Qu,Yonghong Ge
Black spot rot caused by Alternaria alternata is one of the major postharvest disease of apple fruit during logistic. This study evaluated in vitro inhibitory effect of 2-hydroxy-3-phenylpropanoic acid (PLA) at various concentrations on A. alternata and the possible mechanisms involved in its action. Results showed that different concentrations of PLA inhibited conidia germination and mycelial growth of A. alternata in vitro, and 1.0 g L −1 was the lowest effective concentration to suppress A. alternata growth. Moreover, PLA significantly reduced relative conductivity and increased malondialdehyde and soluble protein contents. PLA also increased H 2 O 2 and dehydroascorbic acid contents, but reduced ascorbic acid content. Additionally, PLA treatment inhibited catalase , ascorbate peroxidase , monodehydroascorbate acid reductase, dehydroascorbic acid reductase and glutathione reductase activities, whereas promoted superoxide dismutase activity. All these findings suggest that the possible mechanisms involved in the inhibitory effect of PLA on A. alternata included damaging the cell membrane integrity to cause electrolyte leakage and destroying reactive oxygen species balance.
研究领域:
植物病理学
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微生物学
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采后生理学
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产品关联
DOI
PubMed
高影响因子
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