APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
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2022
·Vol. 106
·期 5
·2007-2015
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IF 5.56
Dong Shuang,Fan Donglin,Liu Qian,Meng Yinyin,Liu Xinyu,Yang Sen,Lin Hui,Li Na,Chen Hongge
Abstract Styrene monooxygenases (SMOs) are powerful enzymes for the synthesis of enantiopure epoxides, but these SMOs have narrow substrate spectra, and the residues in controlling enantioselectivity of SMOs remains unclear. A monooxygenase from Herbaspirillum huttiense ( Hh MO) was found to have excellent enantioselectivities and diastereoselectivities in the epoxidation of unconjugated terminal alkenes. Here we found that Hh MO could also transfer styrene into styrene epoxide with 75% ee, and it could also catalyze the epoxidation of styrene derivatives into the corresponding epoxides with enantioselectivities up to 99% ee. Meanwhile, site 199 in the substrate access channel of Hh MO was found to play an important role in the controlling enantioselectivity of the epoxidation. The E199L variant catalyzed the epoxidation of styrene with > 99% ee. The identification of critical residue that affects the enantioselectivity of SMOs would thus be valuable for creating efficient monooxygenases for the preparation of essential enantiopure epoxides. Key points
Bioexpoxidation of both conjugated and unconjugated alkenes by HhMO with excellent enantioselectivities.
Gating residue 199 played an essential role in controlling the enantioselectivity of SMO.
HhMO E199L catalyzed the epoxidation of styrenes with up to > 99% ee.
研究领域:
生物化学
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酶工程
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DOI
PubMed
高影响因子
Microorganisms
·
2019
·Vol. 7
·期 10
·379
·
IF 4.167
Huanhuan Shao,Meiju Chen,Xueting Fei,Ronglin Zhang,Yue Zhong,Weimin Ni,Xiang Tao,XinYi He,Erliang Zhang,Bin Yong,Xuemei Tan
A bacterial strain,Streptomyces albogriseolusLBX-2, was isolated from a soil sample in Chengdu, China.S. albogriseolusLBX-2 is an aerobic and Gram-positive microorganism that is capable of using the polyethylene as the sole carbon source. Results of scanning electron microscopy and tensile tests indicated thatS. albogriseolusLBX-2 could cause the damages to polyethylene (PE). Suspension culture of LBX-2 resulted in the weight loss in the PE powder over a 15-day period. The bacterial growth curve assay clearly demonstrated the utilization of n-hexadecane and n-octadecane for the strain LBX-2. Phylogenetic analysis showed that it was grouped in the same clade asS. albogriseolusbelonging toStreptomyces. The complete genome of strain LBX-2 consists of a chromosome of 7,210,477 bp and a linear plasmid of 336,677 bp. Compared with other strains ofStreptomyces, the genome size ofS. albogriseolusLBX-2 was smaller than the average but its guanine and cytosine content (72.47%) was higher than the others. The Non-Redundant Protein Database (NR), Kyoto Encyclopedia of Genes and Genomes (KEGG), SwissProt, Gene Ontology (GO) and Clusters of Orthologous Groups (COG) annotations provided information on the specific functions of encoded proteins. A total of 21 monooxygenase and 22 dioxygenase genes were found in its genome. Synteny comparison with the genome ofStreptomyces coelicolorA3(2) revealed a low overall genetic diversity between them. This study provides valuable information to reveal the underlying mechanisms on PE degradation byS. albogriseolusLBX-2.Keywords:Streptomyces albogriseolusLBX-2;polyethylene biodegradation;genome;synteny comparison
研究领域:
微生物学
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环境科学
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基因组学
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PubMed
高影响因子
POLYCYCLIC AROMATIC COMPOUNDS
·
2016
·
IF 0.959
Hongyun Nie,Maiqian Nie,Yongzhe Yang,Jing Zhao,Xinyi Zhang,Yutao Guo,Yi Wan,Jing Zi
Characterization of phenol metabolization by P. stutzeri N2 was proposed based on the identification of relevant metabolites and enzyme activities of catechol 1,2-oxygenase and catechol 2,3-dioxygenase. P. stutzeri N2 started to grow on 400 mg l−1 phenol with no obvious lag phase, and then phenol decomposition was rapidly completed within 32 h. Results of enzyme activities, UV spectrums of cultures, and the mass spectrum identification of cis, cis-muconic and 2-HMS, which showed that catechol C12O and C23O were acting simultaneously on the fission of the phenol ring. The existence of P-hydroxybenzoic acid and straight-chain saturated dicarboxylic acids in the culture medium showed that carboxylation and hydrogenation were involved during the phenol degradation. Metabolites containing five or four carbons indicated that catechol and its immediate ring-cleavage intermediates could be furthermore metabolized by P. Stutzeri N2. Therefore, P. stutzeri N2 which could degrade phenol with high efficiency and diverse pathways could have potential applications in the treatment of wastewater containing phenol.
研究领域:
环境微生物学
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生物化学
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DOI
高影响因子
INTERNATIONAL MICROBIOLOGY
·
2024
·
IF 2.3
Pan Lixu,Yuan Bo,Li Qingqing,Ouyang Ji,Yang Jie,Zhou Yan,Cui Changzheng
Chlorobenzene (CB), extensively used in industrial processes, has emerged as a significant contaminant in soil and groundwater. The eco-friendly and cost-effective microbial remediation has been increasingly favored to address this environmental challenge. In this study, a degrading bacterium was isolated from CB-contaminated soil at a pesticide plant, identified as Pandoraea sp. XJJ-1 (CCTCC M 2021057). This strain completely degraded 100 mg·L −1 CB and showed extensive degradability across a range of pH (5.0–9.0), temperature (10–37 °C), and CB concentrations (100–600 mg·L −1 ). Notably, the degradation efficiency was 85.2% at 15 °C, and the strain could also degrade six other aromatic hydrocarbons, including benzene, toluene, ethylbenzene, and xylene ( o- , m- , p- ). The metabolic pathway of CB was inferred using ultraperformance liquid chromatography, gas chromatography-mass spectrometry, and genomic analysis. In strain XJJ-1, CB was metabolized to o -chlorophenol and 3-chloroxychol by CB monooxygenase, followed by ortho- cleavage by the action of 3-chlorocatechol 1,2-dioxygenase. Moreover, the presence of the chlorobenzene monooxygenation pathway metabolism in strain XJJ-1 is reported for the first time in Pandoraea . As a bacterium with low-temperature resistance and composite pollutant degradation capacity, strain XJJ-1 has the potential application prospects in the in-situ bioremediation of CB-contaminated sites.
研究领域:
环境科学
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微生物学
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生物修复
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生物技术
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DOI
PubMed
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
·
2025
·
IF 3.7
Qian Zhu,Kangning Wei,Kaihua Pan,Gang Hu,Weihao Zhu,Yanni Huang,Changchang Wang,Qian Li,Mingliang Zhang,Jiguo Qiu,Qing Hong
Isoprocarb (IPC), a widely used carbamate insecticide, causes environmental contamination and poses risks to humans and ecosystems. Rhodococcus sp. D-6, capable of utilizing IPC as the sole growth substrate, was isolated by our lab. Strain D-6 initiates IPC degradation through ester bond hydrolysis by the hydrolase IpcH, yielding 2-isopropylphenol (IPP). In this study, the catabolic pathway of IPP in strain D-6 was elucidated, and the ipp gene cluster responsible for its degradation was predicted by transcriptomic analysis. Key genes, including a novel two-component IPP monooxygenase gene ippA1A2 and a 2-isopropylhydroquinone dioxygenase gene ippB, are responsible for the successive conversion of IPP, resulting in the ring cleavage of IPP. IppA1, a group D flavin-dependent monooxygenase, along with its reductase component IppA2, hydroxylates IPP to 2-isopropylhydroquinone using reduced nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) as cofactors. The optimal molar ratio of IppA1 to IppA2 was 3:1. The apparent Km and kcat values of IppA1 for IPP were 60.52 ± 1.27 µM and 70.07 ± 0.85 s−1, respectively. IppB, an extradiol dioxygenase, catalyzes 2-isopropylhydroquinone ring cleavage to generate 2-isopropyl-4-hydroxymuconic semialdehyde. The apparent Km and kcat values of IppB for 2-isopropylhydroquinone were 29.07 ± 1.54 μM and 147.65 ± 1.92 s−1, respectively. This study provides critical insights into the molecular mechanisms of IPP degradation, contributing to a comprehensive understanding of IPC degradation.
研究领域:
环境微生物学
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生物降解
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分子生物学
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生物化学
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基因组学
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农药代谢
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PubMed
高影响因子
Molecular Catalysis
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2022
·
IF 5.089
Shiyu Wei,Guochao Xu,Jieyu Zhou,Ye Ni
Baeyer-Villiger monooxygenases are recognized as valuable tools for biooxidative synthesis of chiral sulfoxides. In this work, a novel HAPMO ortholog from Pseudomonas fluorescens (HAPMO Pf ) was identified by genome mining. Evolutionary relationship and sequence analysis revealed that HAPMO Pf belongs to the family of typical type I BVMOs. HAPMO Pf has a low K M value (0.025 mM) toward 4-hydroxyacetophenone, and a half-life of 24 h at 30 °C and pH 9.0. HAPMO Pf exhibited distinct activity toward aromatic ketones as well as various thioethers, such as methyl phenyl sulfide and bromo‑methyl phenyl sulfide. The highest activities of HAPMO Pf was 1.47 U·mg −1 toward 4-hydroxyacetophenone among tested ketone and thioether substrates. Furthermore, over 95% enantioselectivity was determined toward methyl phenyl sulfides with ortho, meta, and para -substituents (Cl, Br, CHO, NH 2 ). Therefore, HAPMO Pf is a promising biocatalyst for the synthesis of aromatic esters and chiral sulfoxides.
研究领域:
生物化学
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生物催化
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酶学
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DOI
高影响因子
BIODEGRADATION
·
2015
·Vol. 26
·期 3
·197-210
·
IF 2.336
Wang Hong-Wei,Zhang Wei,Su Chun-Lun,Zhu Hong,Dai Chuan-Chao
Phytoestrogens are plant-derived hormonally-active compounds known to cause varied reproductive, immunosuppressive and behavioral effects in vertebrates. In this study, biodegradation of luteolin, a common phytoestrogen, was investigated during incubation with endophytic fungus Phomopsis liquidambari . The optimum concentration of luteolin as sole carbon source supplied in culture was 200 mg L −1 , which allowed 97 and 99 % degradation of luteolin by P. liquidambari in liquid culture and soil conditions, respectively. The investigation of the fungal metabolic pathway showed that luteolin was first decomposed to caffeic acid and phloroglucinol. These intermediate products were degraded to protocatechuic acid and hydroxyquinol, respectively, and then rings were opened by ring-cleavage dioxygenases. Two novel genes encoding the protocatechuate 3,4-dioxygenase and hydroxyquinol 1,2-dioxygenase were successfully cloned. Reverse-transcription quantitative polymerase chain reaction demonstrated that expression levels of mRNA of these two genes increased significantly after P. liquidambari was induced by the intermediate products caffeic acid and phloroglucinol, respectively. These results revealed that P. liquidambari can biodegrade luteolin efficiently and could potentially be used to bioremediate phytoestrogen contamination.
研究领域:
环境科学
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微生物学
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分子生物学
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DOI
PubMed
高影响因子
ENVIRONMENTAL MICROBIOLOGY
·
2021
·Vol. 23
·期 5
·2550-2563
·
IF 5.491
Shunyao Li,Kai Sun,Xin Yan,Chao Lu,Michael Gatheru Waigi,Juan Liu,Wanting Ling
Summary Novosphingobium sp. ES2-1 is an efficient 17 β -estradiol (E2)-degrading bacterium, which can convert E2 to estrone (E1), then to 4-hydroxyestrone (4-OH-E1) for subsequent oxidative cracking. In this study, the molecular bases for this process were elucidated. Two novel monooxygenase systems EstP and EstO were shown to catalyse the oxygenation of E1 and 4-OH-E1, respectively. EstP was a three-component cytochrome P450 monooxygenase system consisting of EstP1 (P450 monooxygenase), EstP2 (ferredoxin) and EstP3 (ferredoxin reductase). Ultraperformance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) analysis revealed that EstP catalysed the 4-hydroxylation of E1 to produce 4-OH-E1. The resultant 4-OH-E1 was further oxidized by a two-component monooxygenase system EstO consisting of EstO1 (flavin-dependent monooxygenases) and EstO2 (flavin reductase). UPLC-HRMS combined with 1 H-nuclear magnetic resonance analysis demonstrated that EstO catalysed the breakage of C9-C10 to yield a ring B-cleavage product. In addition, the oxygenase component genes estP1 and estO1 exhibited contrary inductive behaviours when exposed to different steroids, suggesting that EstP1-mediated 4-hydroxylation was E2-specific, whereas EstO1-mediated monooxygenation might be involved in the degradation of testosterone, androstenedione, progesterone and pregnenolone. This also implied that the mechanisms of the catabolism of different steroids by the same microorganism might be partially interlinked.
研究领域:
微生物学
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环境科学
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生物化学
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高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2020
·
IF 9.038
Yunli Liu,Haiyang Hu,Giulio Zanaroli,Ping Xu,Hongzhi Tang
Polycyclic aromatic hydrocarbons (PAHs) and heterocyclic derivatives are organic pollutants that pose a serious health risk to human beings. In this study, a newly isolated Pseudomonas brassicacearum strain MPDS could effectively degrade PAHs and heterocyclic derivatives, including naphthalene , fluorene, dibenzofuran (DBF) and dibenzothiophene (DBT). Notably, strain MPDS is able to degrade fluorene, DBF and DBT uniquely via a lateral dioxygenation pathway, while most reported strains degrade fluorene, DBF and DBT via an angular dioxygenation pathway or co-metabolize them via a lateral dioxygenation pathway. Strain MPDS completely degraded 50 mg naphthalene (in 50 mL medium) in 84 h, and OD 600 reached 1.0–1.1; while, it stabilized at OD 600 0.5–0.6 with 5 mg fluorene or DBF or DBT. Meanwhile, 65.7% DBF and 32.1% DBT were degraded in 96 h, and 40.3% fluorene was degraded in 72 h, respectively. Through genomic and transcriptomic analyses, and comparative genomic analysis with another DBF degradation strain, relevant gene clusters were predicted, and a naphthalene-degrading gene cluster was identified. This study provides understanding of degradation of PAHs and their heterocyclic derivatives, as well as new insights into the lateral dioxygenation pathway of relevant contaminants.
研究领域:
环境微生物学
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生物修复
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基因组学
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DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2021
·
IF 9.381
Lei Ma,Zhiying Liu,Zhijian Kong,Mengmeng Wang,Tuo Li,Han Zhu,Qun Wan,Dongyang Liu,Qirong Shen
Lytic polysaccharide monooxygenases (LPMOs) are attracting much attention for their potential application in biodegradation. However, there are limited studies on the characterization of the AA11 family. Here, a novel AA11 family protein, Tg AA11, from Trichoderma guizhouense NJAU 4742 was characterized, and the isothermal titration calorimetry (ITC) analysis results showed that it exhibited tight binding capacity for copper ions with a K d value of 4.83 ± 0.79 μM. The MALDI-TOF-MS analysis results indicated that Tg AA11 could act on β-chitin to form C1 oxidation products, and some deacetylated chitooligosaccharides. In addition, the degradation of α-chitin and β-chitin by a chitinolytic enzyme Sg -chi was substantially increased in the presence of Tg AA11 by 39.9 % and 288.2 %, respectively. Furthermore, the active site residues predicted showed that His61 and Tyr142 might be critical for the active site residues of the Tg AA11 protein. This study will contribute to the understanding of the function of AA11 LPMOs in the degradation of chitin.
研究领域:
微生物学
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生物化学
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PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2020
·
IF 4.192
Yidong Zhou,Zhijian Ke,Hangting Ye,Mengting Hong,Yifei Xu,Mingliang Zhang,Wankui Jiang,Qing Hong
Carbaryl is a widely used carbamate pesticide in agriculture. The strain Rhizobium sp. X9 possesses the typical carbaryl degradation pathway in which carbaryl is mineralized via 1-naphthol, salicylate, and gentisate. In this study, we cloned a carbaryl hydrolase gene cehA and a novel two-component 1-naphthol hydroxylase gene cehC1C2. CehA mediates carbaryl hydrolysis to 1-naphthol and CehC1, an FMNH2 or FADH2-dependent monooxygenase belonging to the HpaB superfamily, and hydroxylates 1-naphthol in the presence of reduced nicotinamide-adenine dinucleotide (FMN)/flavin adenine dinucleotide (FAD), and the reductase CehC2. CehC1 has the highest amino acid similarity (58%) with the oxygenase component of a two-component 4-nitrophenol 2-monooxygenase, while CehC2 has the highest amino acid similarity (46%) with its reductase component. CehC1C2 could utilize both FAD and FMN as the cofactor during the hydroxylation, although higher catalytic activity was observed with FAD as the cofactor. The optimal molar ratio of CehC1 to CehC2 was 2:1. The Km and Kcat/Km values of CehC1 for 1-naphthol were 74.71 ± 16.07 μM and (8.29 ± 2.44) × 10–4 s–1·μM–1, respectively. Moreover, the enzyme activities and substrate spectrum between CehC1C2 and previously reported 1-naphthol hydroxylase McbC were compared. The results suggested that McbC had a higher 1-naphthol hydroxylation activity, while CehC1C2 had a broader substrate spectrum.
研究领域:
环境微生物学
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生物化学
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农药生物降解
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PubMed
高影响因子
TOXICOLOGY AND APPLIED PHARMACOLOGY
·
2025
·
IF 3.4
Xuemin Xian,Xin Zhao,Xingchen Zhou,Hanfang Liu,Changxi Li,Xinquan Wu,Yuhang Chen,Keyue Ye,Hongwei Yang,Mingxi Li,Jianyun Yan,Xiuli Zhang
Vascular calcification (VC) is a common complication of chronic kidney disease (CKD), with oxidative stress identified as a key contributor to VC progression. Honokiol (HKL), a biphenolic compound derived from plants, has been found to be effective in treating various models of cardiovascular disease through the mitigation of oxidative stress. However, its effects on VC remain unexplored. To elucidate the effects of HKL on VC, a CKD rat model, a vitamin D 3 -overload-induced mouse model of vascular calcification, and a high-phosphate-induced human vascular smooth muscle cell (VSMC) calcification model were established. Calcification levels were assessed using Alizarin Red staining, calcium quantification, and Western blotting of osteogenic markers. Oxidative stress was assessed by measuring reactive oxygen species. Furthermore, transcriptome sequencing was employed to identify molecules and pathways affected by HKL. HKL was found to significantly reduce calcification in both in vivo and in vitro models. It also mitigated oxidative stress induced by high phosphate in human VSMCs. Mechanistically, HKL upregulated heme oxygenase-1 (HMOX-1), thereby inhibiting oxidative stress and reducing calcification. Pharmacological inhibition of HMOX-1 counteracted the protective effect of HKL on vascular calcification. In summary, the findings suggest that HKL ameliorates VC by upregulating HMOX-1 and decreasing oxidative stress.
研究领域:
医学
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药理学
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PubMed
高影响因子
危险品化学品经营许可证（带存储）