WATER RESEARCH
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2025
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IF 12.4
Junwei Liu,Xinyue Yang,Tao Gao,Yuehan Zhang,Dandan Pan,Jian He,Xiangwei Wu
The widespread use of sulfamethoxazole (SMX) has raised significant concerns regarding environmental residue pollution and the emergence of bacterial antibiotic resistance. Anaerobes play crucial roles in the biogeochemical element cycle and the degradation of organic pollutants; however, the pure-cultured anaerobes involved in SMX anaerobic degradation and their underlying mechanisms remain largely unknown. In this study, a novel anaerobic bacterium, Cupidesulfovibrio sp. strain SA-9, was isolated and characterized for its ability to degrade SMX. Strain SA-9 preferentially utilized lactate or pyruvate as electron donors and sulfate, nitrate, or carbonate as electron acceptors to drive SMX degradation. The degradation T 1/2 values of SMX at concentrations ranging from 10 to 800 μM were between 6.0 and 17.2 d under optimal conditions which included pH 7.0-8.0, 30–37°C, sulfate as the electron acceptor, and pyruvate as the electron donor. Strain SA-9 degraded SMX via isoxazole ring cleavage, acetylation, and hydroxylation, and the ECOSAR-predicted results and bacterial growth inhibition assays indicated that these pathways was detoxifying. Multi-omics analysis and heterologous expression revealed that strain SA-9 degraded SMX via a reductive transformation pathway fueled by electron donors oxidized through the TCA cycle, with electrons transferred through a chain involving flavin-dependent thymidylate synthase (FDTS) and ferredoxin (Fd) to reduce electron acceptors that provide reducing power for SMX degradation. Furthermore, the degradation half-life ( T 1/2 ) values of SMX at 10 and 50 μM were 1.7 and 1.8 d in actual wastewater. Strain SA-9 significantly enhanced SMX removal and mitigated the dissemination risk of ARGs sul1 and sul2 in actual wastewater. This study elucidates the anaerobic microbial resistance mechanism to SMX and highlights the potential of strain SA-9 for the bioremediation of SMX-contaminated water.
研究领域:
环境微生物学
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污染物生物降解
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厌氧代谢
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抗生素抗性基因
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分子生态学
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药物代谢
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水环境修复
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微生物生理学
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高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2022
·Vol. 106
·期 7
·2619-2636
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IF 5.56
Chen Yunni,Xu Chenglong,Yang Huilin,Liu Zhenying,Zhang Zhibin,Yan Riming,Zhu Du
Abstract Perylenequinones (PQ) are natural polyketides used as anti-microbial, -cancers, and -viral photodynamic therapy agents. Herein, the effects of L-arginine (Arg) on PQ biosynthesis of Shiraia sp. Slf14(w) and the underlying molecular mechanism were investigated. The total content of PQ reached 817.64 ± 72.53 mg/L under optimal conditions of Arg addition, indicating a 30.52-fold improvement over controls. Comparative transcriptome analysis demonstrated that Arg supplement promoted PQ precursors biosynthesis of Slf14(w) by upregulating the expression of critical genes associated with the glycolysis pathway, and acetyl-CoA and malonyl-CoA synthesis. By downregulating the expression of genes related to the glyoxylate cycle pathway and succinate dehydrogenase, more acetyl-CoA flow into the formation of PQ. Arg supplement upregulated the putative biosynthetic gene clusters for PQ and activated the transporter proteins (MFS and ABC) for exudation of PQ. Further studies showed that Arg increased the gene transcription levels of nitric oxide synthase (NOS) and nitrate reductase (NR), and activated NOS and NR, thus promoting the formation of nitric oxide (NO). A supplement of NO donor sodium nitroprusside (SNP) also confirmed that NO triggered promoted biosynthesis and efflux of PQ. PQ production stimulated by Arg or/and SNP can be significantly inhibited upon the addition of NO scavenger carboxy-PTIO, NOS inhibitor N ω -nitro-L-arginine, or soluble guanylate cyclase inhibitor NS-2028. These results showed that Arg-derived NO, as a signaling molecule, is involved in the biosynthesis and regulation of PQ in Slf14(W) through the NO-cGMP-PKG signaling pathway. Our results provide a valuable strategy for large-scale PQ production and contribute to further understanding of NO signaling in the fungal metabolite biosynthesis. Key points • PQ production of Shiraia sp. Slf14(w) was significantly improved by L-arginine addition. • Arginine-derived NO was firstly reported to be involved in the biosynthesis and regulation of PQ. • The NO-cGMP-PKG signaling pathway was proposed for the first time to participate in PQ biosynthesis.
研究领域:
微生物学
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生物化学
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药理学
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分子生物学
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真菌代谢
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高影响因子
FOOD CHEMISTRY
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2021
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IF 7.514
Chenlu Zhu,Zebin Liu,Lishi Ren,Siming Jiao,Xuebing Zhang,Qiukuan Wang,Zhimin Li,Yuguang Du,Jian-Jun Li
Endo -fucoidanases are important in structural analysis of fucoidans and preparation of fuco-oligosaccharides. However their enzymological properties and analysis of degradation products are scarcely investigated. Truncated endo - α (1 → 3)-fucoidanase Fda1 (tFda1B from Alteromonas sp. was overexpressed and characterized, showing highest activity at pH 7.0, 35 °C, and 1.0 M NaCl. Its K m and k cat were 3.88 ± 0.81 mg/mL and 0.82 ± 0.17 min −1 . Fe 3+ and Mn 2+ enhanced activity by 100% and 19.5% respectively. Co 2+ and Cu 2+ completely inactivated tFda1B, whereas Ni 2+ , Mg 2+ , Zn 2+ , Pb 2+ , Ca 2+ , Ba 2+ and Li + decreased activity by 58.8%, 56.0%, 50.6%, 47.7%, 28.9%, 15.6% and 37.5%, respectively. Catalytic residues were identified through structure and sequence alignment, and confirmed by mutagenesis. Degradation products of Kjellmaniella crassifolia fucoidan by tFda1B were characterized by LC-ESI-MS/MS, confirming tFda1B belongs to endo -(1 → 3)-fucoidanases, and backbone of K. crassifolia fucoidan is 1 → 3 fucoside linkage. This endo - α (1 → 3)-fucoidanase would be useful for elucidating fucoidan structures, and be used as a food enzyme.
研究领域:
生物化学
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酶学
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海洋生物技术
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分析化学
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PubMed
高影响因子
BIORESOURCE TECHNOLOGY
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2021
·
IF 9.642
Zhendong Bao,Yuanmin Zhu,Yumei Feng,Kai Zhang,Meng Zhang,Zhikuan Wang,Longjiang Yu
Schizochytrium sp. is one of the most promising marine oleaginous microorganisms for industrial production of docosahexaenoic acid (DHA). In this study, the exogenous supplementation of 1 mM sesamol to the fermentation medium effectively prevented the peroxidation of polyunsaturated fatty acids in the fermentation process, which thereby significantly increasing the lipid and DHA yield by 53.52% and 78.30%, respectively. The addition of sesamol also increased the total antioxidant capacity of cells and induce the gene expression of polyketide synthase and antioxidant enzyme system. Moreover, the supply of nicotinamide adenine dinucleotide phosphate was regulated by sesamol by inhibiting the malic enzyme activity and promoting the glucose-6-phosphate dehydrogenase activity. Finally, fed-batch fermentation showed that the addition of sesamol significantly enhanced the DHA yield by 90.76%. This study provides an important reference for enhancing the DHA productivity of Schizochytrium sp. in industrial fermentation.
研究领域:
微生物学
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生物技术
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生物化学
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高影响因子
Frontiers in Microbiology
·
2026
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IF 5.8
Lin Jiang,Xiaofang Yan,Fang Zhang,Ailing Chen,Yixuan Chen,Yongbiao Zheng,Lingjun Yu
Introduction N -acetylglucosamine (GlcNAc) serves as a signaling molecule that triggers a variety of physiological responses in microorganisms. However, its regulatory roles in metabolite biosynthesis and siderophore production in Lysobacter sp. 3655 remain unclear, especially regarding the quorum sensing (QS) signal 4-hydroxybenzoic acid (4-HBA) and the siderophore lysochelin under iron-deficient conditions. This study aimed to explore the regulatory effects of GlcNAc on metabolite profiles and lysochelin biosynthesis in Lysobacter sp. 3655. Methods Lysobacter sp. 3655 was cultured in oligotrophic medium with GlcNAc induction. The induced differential metabolite was isolated and structurally identified by nuclear magnetic resonance and liquid chromatography-mass spectrometry. Gene deletion mutants of GlcNAc catabolic genes ( nagA , nagE2 ), and L-phenylalanine biosynthesis gene (pheA) were constructed, as well as multiple deletion mutants in the lenB2 (4-HBA biosynthetic gene) mutant background. Growth status and lysochelin yield of these mutants were evaluated under iron-deficient conditions. Exogenous complementation assays were performed using 4-HBA, GlcNAc, p -hydroxybenzaldehyde, cinnamic acid, and p-hydroxycinnamic acid to verify their functional effects. Results GlcNAc specifically induced the production of a unique metabolite in Lysobacter sp. 3655, which was identified as p -hydroxybenzaldehyde. Deletion of nagA , nagE2 , or pheA completely abolished GlcNAc-induced p -hydroxybenzaldehyde biosynthesis. The lenB2 mutant showed significant growth defects and remarkably decreased lysochelin production under iron limitation, while exogenous 4-HBA or GlcNAc restored both phenotypes. Further disruption of nagA , nagE2 , or pheA in the lenB2 mutant eliminated the complementation effect of GlcNAc on lysochelin production. p -hydroxybenzaldehyde restored lysochelin biosynthesis by converting to 4-HBA, and the L-phenylalanine catabolic intermediates cinnamic acid and p-hydroxycinnamic acid also rescued the growth and lysochelin production defects of the lenB2 mutant. Discussion Our results reveal that GlcNAc regulates two metabolic pathways in Lysobacter sp. 3655: it promotes p -hydroxybenzaldehyde production through GlcNAc catabolism and L-phenylalanine metabolism, and restores lysochelin biosynthesis in the QS-deficient lenB2 mutant via either 4-HBA converted from p -hydroxybenzaldehyde or alternative pathways mediated by L-phenylalanine catabolites. These findings uncover a novel regulatory network controlling lysochelin biosynthesis in Lysobacter sp. 3655, providing important references for investigating the biocontrol mechanisms of Lysobacter species.
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ENVIRONMENTAL AND EXPERIMENTAL BOTANY
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2026
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IF 5.1
Bocheng Su,Jianke Huang,Enci Ye,Xiwen Xue,Jindong Zhao,Zi Ye
Glucose increased Chlorella biomass by counteracting Cd inhibition. • Cd 2+ disrupts cell wall degradation and photosynthetic systems. • Glucose co-treatment restored the cell wall degradation and chlorophyll homeostasis. Cadmium (Cd) pollution is a growing environmental challenge worldwide, impairing cellular integrity and transcriptional regulation across species and undermining ecosystem stability. This study investigates the effects of Cd 2 + stress on Chlorella pyrenoidosa in terms of growth, cell division, and photosynthetic function, and evaluates the alleviating role of soluble organic carbon supplementation, using glucose as a representative source. Results indicate that Cd 2+ exposure markedly suppresses algal growth, disrupts photosynthetic systems, reduces chlorophyll content, diminishes key photosynthetic metrics, and interferes with cell wall degradation. Biomass and specific growth rate declined from 0.6 g L −1 and 0.49 d −1 in controls to 0.38 g L −1 and 0.42 d −1 under Cd 2+ stress, but recovered to 0.95 g L −1 and 0.61 d −1 with glucose addition. Glucose supplementation substantially counteracted these inhibitory effects, partially reviving photosynthetic activity through enhanced QA-to-QB electron transfer and stabilization of porphyrin metabolism. Transcriptomic profiling revealed that Cd 2+ downregulated genes involved in cellulose degradation while upregulating those associated with lignin biosynthesis; glucose treatment restored the expression of lignin-related genes to near-control levels. Collectively, our findings demonstrate that glucose alleviates Cd 2+ toxicity in C. pyrenoidosa by restoring photosynthetic competence and cell division capacity, thereby elucidating key metabolic pathways underlying heavy-metal detoxification. Download: Download high-res image (150KB) Download: Download full-size image
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BIOORGANIC CHEMISTRY
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2025
·
IF 4.7
Yin-Yin Wang,Yu-Song Wang,Jun-Jiang Li,Ze-Yi Wan,Hua Zhang
Seven unreported chaetoglobosin-type alkaloids, namely brachaetoglobosin A ( 1 ), chaetochalasins B F ( 2 – 6 ) and armochaeglobine C ( 7 ), together with the formerly described cytoglobosin C ( 8 ) and chaetoglobosin E ( 9 ), were obtained from an endophytic fungus Chaetomium sp. UJN-EF006 isolated from the leaves of Vaccinium bracteatum . Their structures were characterized through various spectral techniques including MS, NMR, X-ray crystallography and electronic circular dichroism. Also, this is only the second record of novel chaetochalasin and armochaeglobine skeletons of the cytochalasin super family, after 27 and 10 years of the first report, respectively. Compound 9 showed significant cytotoxic effect against two human tumor cell lines (MDA-MB231 and A549) and was identified as a new type of ferroptosis inducer (toward A549 cells) that could be used as a molecular tool in future related research.
研究领域:
真菌学
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天然产物化学
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药理学
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PubMed
高影响因子
iScience
·
2025
·Vol. 28
·期 12
·
IF 4.1
Yao Di,Wenfei Luan,Lihua Sun,Jing Qi,Hongmei Xia,Fan Li,Niu Zhai
Poly(ε-caprolactone) (PCL) is a widely used synthetic polymer with significant commercial applications, and its degradation and synthesis have become the focus of considerable research. In this study, we purified a PCL-degrading enzyme, PCLase0801, produced by Pseudomonas sp. DS0801. The enzyme was purified to homogeneity and had a molecular weight of 30.4 kDa. It exhibited optimal activity at 40°C and pH 8.0, hydrolyzing PCL into monomers, dimers, and trimers. The enzyme was identified as a lipase and showed good tolerance to organic solvents. Additionally, PCLase0801 catalyzed the ring-opening polymerization of ε-caprolactone, producing PCL with a molecular weight of 6050 g/mol and favorable structural properties. This work provides new insights into the potential applications of PCL-degrading enzymes in PCL treatment and biosynthesis.
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JOURNAL OF HAZARDOUS MATERIALS
·
2025
·
IF 11.3
Lan Qiu,Xiaoyuan Guo,Hojae Shim,Tianwei Hao,Zhiwei Liang,Shanquan Wang,Zhenmei Lu,Qihong Lu,Zhili He
The polychlorinated aromatic antimicrobial agent triclosan (TCS) is widely used to indiscriminately and rapidly kill microorganisms. The global use of TCS has led to widespread environmental contamination, posing significant threats to ecosystem and human health. Here we reported a newly isolated Pseudomonas sp. W03 for degrading TCS metabolically at concentrations up to 10 mg/L. This strain exhibited optimal degradation activity at 30°C and pH 7.0, and retained substantial activity at pH 4.0, although it was sensitive to alkaline conditions. Genomic analysis of strain W03 revealed a circular chromosome comprising 6075,907 bp with a GC content of 65.08 %. A novel TCS degradation pathway, involving dechlorination, oxidation, ether bond fission, and reoxidation processes, was identified. Also, the study mapped the global distribution of analogous Pseudomonas using 16S rRNA gene sequences, revealing their widespread presence in diverse aquatic environments, with a significant abundance in wastewater systems. These findings indicated that these bacteria play a critical ecological role in both natural and engineered environments, particularly in the degradation of organic pollutants. This study enhances our understanding of microbial degradation of emerging contaminants and presents a promising candidate for bioremediation strategies aimed at mitigating TCS-related water pollution.
研究领域:
微生物学
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环境科学
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生态学
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高影响因子
Journal of Water Process Engineering
·
2025
·
IF 6.7
Mi Feng,Junjie Zhao,Yanqin Lu,Xuan Luo,Xinghui Feng,Yao Huang,Zijun Chen,Dongxia Fu,Jianhua Chen
Streptomyces sp. FW-32, an actinobacterial strain capable of degrading 3,6-dibromocarbazole (3,6-DBCZ), was isolated from polluted soils. >85 % of 3,6-DBCZ was degraded within 5 d under optimal conditions (glucose concentration of 5 g/L, pH of 7, initial 3,6-DBCZ concentration of 1 mg/L, temperature of 35 °C). The biodegradation of 3,6-DBCZ followed the first-order kinetic model with the degradation rate constant of 0.01713 h −1 . Biodegradation pathways of 3,6-DBCZ by Streptomyces sp. FW-32 were proposed, including debromination, oxidation, and aromatic ring cleavage. The intracellular enzymes of Streptomyces sp. FW-32, such as cytochrome P450, played an important role in 3,6-DBCZ biodegradation. In the earlier stage of 3,6-DBCZ biodegradation (1–2 d), the activities of SOD and CAT were enhanced by 3,6-DBCZ (≤10 mg/L), but 10 mg/L of 3,6-DBCZ inhibited the activities of these two antioxidant enzymes at the later period (4–6 days). Cell viability of strain FW-32 was stimulated by 3,6-DBCZ at 1 mg/L in the first two days of treatment, but it was suppressed by 10 mg/L of 3,6-DBCZ after 3 days of exposure. Strain FW-32 was able to efficiently degrade 3,6-DBCZ and its key intermediate carbazole in real river water. The results of this study illuminated the mechanism of 3,6-DBCZ biodegradation by a newly isolated strain FW-32 and indicated that strain FW-32 might be suitable for the elimination of 3,6-DBCZ from contaminated water. Overall, these findings were significant for developing microbial remediation to control 3,6-DBCZ pollution in water environments.
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Life-Basel
·
2026
·Vol. 16
·期 2
·
IF 3.9
Xinyuan Wei,Haoyu Wang,Rui Li,Shengmin Liu,Hongyan Zuo,Qing Hu,Xuliang Zhuang,Zhihui Bai
Petroleum contamination poses a serious threat to human health and ecosystems worldwide, and microbially driven natural attenuation is an effective approach for accelerating hydrocarbon removal. Species of the genusRhodococcusare recognized for their ability to degrade long chain petroleum hydrocarbons. However, their physiological traits and degradation mechanisms under alkaline conditions remain insufficiently understood. In this study, soil samples were collected from the Dagang oilfield in Tianjin, China, andRhodococcussp. A17 was isolated as an active indigenous strain for genomic and physiological characterization under high pH petroleum degradation conditions. The results showed that strain A17 grew optimally at 30 °C, pH 9.0, and 2% salinity. Petroleum hydrocarbon degradation reached 67.8% within 72 h, with a degradation half life of 34.2 h. Genome sequencing identified 18 oxygenase related genes involved in alkane degradation, includingalkB, cytochrome P450 monooxygenases, and the long chain alkane monooxygenaseladA, together with four antibiotic resistance genes. Metabolite analysis suggested that alkane degradation might proceed via terminal and subterminal oxidation pathways. Overall, these findings indicate thatRhodococcussp. A17 exhibits multiple adaptive traits that support its potential application in the bioremediation of petroleum contaminated alkaline environments.
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ENVIRONMENTAL RESEARCH
·
2023
·
IF 8.3
Ni-Hong Yao,Ya-Nan Du,Jia-Xi Xiong,Ying Xiao,Hang-Hang He,Ze-Feng Xie,Duo Huang,Qi Song,Jing Chen,Dazhong Yan,Hong-Jun Chao
The compound 3,5-xylenol is an essential precursor used in pesticides and industrial intermediate in the disinfectants and preservatives industry. Its widespread application makes it an important source of pollution. Microbial bioremediation is more environmentally friendly than the physicochemical treatment process for removing alkylphenols from a polluted environment. However, the 3,5-xylenol-degrading bacteria is unavailable, and its degradation mechanism remains unclear. Here, a 3,5-xylenol-metabolizing bacterial strain, designated Rhodococcus sp. CHJ602, was isolated using 3,5-xylenol as the sole source of carbon and energy from a wastewater treatment factory. Results showed that strain CHJ602 maintained a high 3,5-xylenol-degrading performance under the conditions of 30.15 °C and pH 7.37. The pathway involved in 3,5-xylenol degradation by strain CHJ602 must be induced by 3,5-xylenol. Based on the identification of intermediate metabolites and enzyme activities , this bacterium could oxidize 3,5-xylenol by a novel metabolic pathway. One methyl oxidation converted 3,5-xylenol to 3-hydroxymethyl-5-methylphenol, 3-hydroxy-5-methyl benzaldehyde, and 3-hydroxy-5-methylbenzoate. After that, another methyl oxidation is converted to 5-hydroxyisophthalicate, which is metabolized by the protocatechuate pathway. It is catalyzed by a series of enzymes in strain CHJ602. In addition, toxicity bioassay result indicates that 3,5-xylenol is toxic to zebrafish and Rhodococcus sp. CHJ602 could eliminate 3,5-xylenol in water to protect zebrafish from its toxicity. The results provide insights into the bioremediation of wastewater contaminated 3,5-xylenol.
研究领域:
环境科学
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微生物学
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高影响因子
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