JOURNAL OF HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Dong Hui Liang,Yongyou Hu
Little information is available regarding the kinetics, products, and pathways of simultaneous SMX degradation and Cd(II) immobilization from wastewater. In this study, a novel bacterium ( Achromobacter sp. L3) with SMX degradation and Cd(II) immobilization capabilities was isolated. The boundary conditions of SMX degradation were as follows: initial pH 6–8, temperature 25–30 °C, and SMX concentration 10–40 mg/L −1 . The boundary conditions of Cd(II) immobilization were as follows: initial pH 7–9, temperature 25–35 °C, and SMX concentration 10–30 mg/L −1 . The maximum SMX degradation and Cd(II) removal were 91.98% and 100%, respectively. The SMX degradation and Cd(II) immobilization data fitted well with the pseudo-first-order kinetic model, indicating that the two pollutants conform to the same degradation rule. Moreover, the microbial degradation , sediment adsorption, and intermediates identified in the experiments were used to explore the mechanisms of SMX and Cd(II) removal. These results indicate that microbial removal and sediment adsorption play equally important roles in Cd(II) immobilization; however, microbial degradation plays a decisive role in SMX degradation. Furthermore, the relationship between aerobic denitrification, SMX degradation, and Cd(II) immobilization was proposed. These results may provide valuable insights for treatment of wastewater polluted by antibiotics and heavy metals.
研究领域:
环境微生物学
·
废水工程
·
污染控制
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PubMed
高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2013
·Vol. 97
·期 24
·10329-10337
·
IF 3.689
He Yu-Cai,Ma Cui-Luan,Yang Zhen-Xing,Zhou Min,Xing Zhen,Ma Jiang-Tao,Yu Hui-Lei
Enantiopure sulfoxides can be prepared via the asymmetric oxidation of sulfides using sulfide monooxygenases. The n -octane–water biphasic system was chosen for the bio-oxidation of a water-insoluble phenyl methyl sulfide (PMS) by Rhodococcus sp. CCZU10-1. In this n -octane–water system, the optimum reaction conditions were obtained. ( S )-phenyl methyl sulfoxide (( S )-PMSO) with >99.9 % enantiomeric excess formed at 55.3 mM in the n -octane–water biphasic system. Using fed-batch method, a total of 118 mM ( S )-PMSO accumulated in 1-L reaction mixture after the 7th feed, and no ( R )-PMSO and sulfone were detected. Moreover, Rhodococcus sp. CCZU10-1 displayed fairly good activity and enantioselectivity toward other sulfides. In conclusion, Rhodococcus sp. CCZU10-1 is a promising biocatalyst for synthesizing highly optically active sulfoxides.
研究领域:
生物化学
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微生物学
·
有机合成
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PubMed
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2019
·
IF 4.527
Feng Li,Yang Zheng,Jiang Tian,Fei Ge,Xingwang Liu,Yixin Tang,Chuang Feng
This study investigated the effects of Cupriavidus sp. strain Cd02-mediated increase on biosorption and bioprecipitation of Cd 2+ during the 144-h cultivation time as well as evaluated effectivenesses of changing soil pH and bioavailability of cadmium after bioaugmentation of strain Cd02 into Cd-contaminated paddy soil for 15 days. Results showed that strain Cd02-induced pH increase of the culture medium (from 7.40 to 8.68) facilitated biosorption of Cd 2+ on Cd02 cell surface (4.82 mg/mg) and extracellular bioprecipitation in form of cadmium carbonate (3.07 mg/mg). Also, the pH values of Cd-contaminated paddy soil increased by 1.41 units after strain Cd02 was applied for 15 days, which thereby promoted the decrease of exchangeable fraction of Cd 2+ by 6.5% in the tested paddy soil. Meanwhile, strain Cd02 could prosperously live in paddy soils after bioaugmentation. These results suggest that strain Cd02 may be applicable for bioremediation of the heavy metal-contaminated soils by bioaugmentation.
研究领域:
环境微生物学
·
土壤学
·
生物修复
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PubMed
高影响因子
CHEMISTRY & BIODIVERSITY
·
2021
·Vol. 18
·期 7
·e2100229
·
IF 2.408
Wenjuan Ding,Fangfang Wang,Qingwen Li,Yaxin Xue,Zhitong Dong,Danmei Tian,Mei Chen,Youwei Zhang,Kui Hong,Jinshan Tang
Marine derived fungus has gained increasing ground in the discovery of novel lead compounds with potent biological activities including anti-inflammation. Here, we first report the characterization of one new sorbicillinoid ( 1 ) and fourteen known compounds ( 2 – 15 ) from the ethyl acetate (AcOEt) extract of a cultured mangrove derived fungus Penicillium sp. DM815 by UV, IR, HR ESI-Q-TOF MS, and NMR spectra. We then evaluated the anti-inflammatory effects of eleven sorbicillinoids ( 1 – 11 ) using cultured macrophage RAW264.7 cells. The results show that compound 9 , and to a lesser degree compound 5 , significantly inhibited the Gram-negative bacteria lipopolysaccharide (LPS)-induced upregulation of the inducible nitric oxide synthase (iNOS). Consistently, compounds 5 and 9 significantly reduced the level of nitric oxide (NO), the product of iNOS, induced by LPS. We further show that these two compounds dose-dependently inhibited LPS-triggered iNOS expression and NO production, but had no effect on proliferation of RAW264.7 cells in the presence of LPS. In conclusion, our study identifies novel and known sorbicillinoids as potent anti-inflammatory agents, holding the promise of developing novel anti-inflammation treatment in the future.
研究领域:
药理学
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微生物学
·
化学
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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
·
生物化学
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PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2023
·
IF 9.8
Zhen Rong,Zhi-Hao Ding,Yue-Hong Wu,Xue-Wei Xu
Low-density polyethylene (LDPE), which accounts for 20% of the global plastic production, is discharged in great quantities into the ocean, threatening marine life and ecosystems. Marine microorganisms have previously been reported to degrade LDPE plastics; however, the exploration of strains and enzymes that degrade LDPE is still limited. Here, an LDPE-degrading bacterium was isolated from seawater of the Changjiang Estuary, China and identified as Rhodococcus sp. C-2, the relative abundance of which was dramatically enhanced during PE-degrading microbial enrichment. The strain C-2 exhibited the degradation of LDPE films, leading to their morphological deterioration, reduced hydrophobicity and tensile strength, weight loss, as well as the formation of oxygen-containing functional groups in short-chain products. Sixteen bacterial enzymes potentially involved in LDPE degradation were screened using genomic, transcriptomic, and degradation product analyses. Thereinto, the glutathione peroxidase GPx with exposed active sites catalyzed the LDPE depolymerization with the cooperation of its dissociated superoxide anion radicals. Furthermore, an LDPE degradation model involving multiple enzymes was proposed. The present study identifies a novel PE-degrading enzyme (PEase) for polyethylene bioremediation and promotes the understanding of LDPE degradation.
研究领域:
环境科学
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微生物学
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生物技术
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材料科学
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高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2014
·Vol. 172
·期 5
·2540-2551
·
IF 1.687
Jia Dongxu,Yang Yu,Peng Zhengcong,Zhang Dongxu,Li Jianghua,Liu Long,Du Guocheng,Chen Jian
Poly(vinyl alcohol) dehydrogenase (PVADH, EC 1.1.99.23) is an enzyme which has potential application in textile industry to degrade the poly(vinyl alcohol) (PVA) in waste water. Previously, a 1,965-bp fragment encoding a PVADH from Sphingopyxis sp. 113P3 was synthesized based on the replacement of the rare codons in Escherichia coli ( E. coli ). In this work, the deduced mature PVADH ( mPVADH ) gene of 1,887 bp was amplified by polymerase chain reaction (PCR) and inserted into the site between Nco I and Hin dIII in pET-32a(+). The constructed recombinant plasmid was transformed into E. coli Rosetta (DE3). In shake flask, the fusion protein of thioredoxin (Trx)-mPVADH was expressed precisely; however, Trx-mPVADH was found to accumulate mainly as inclusion bodies. After isolating, dissolving in buffer containing urea, purification, dialysis renaturation, and digesting with recombinant enterokinase/His (rEK/His), the bioactive mPVADH fragments were obtained with protein concentration of 0.56 g/L and enzymatic activity of 194 U/mL. The K
m and V
max values for PVA 1799 were 2.33 mg/mL and 15.7 nmol/(min·mg protein), respectively. 1 H-NMR and infrared (IR) spectrum demonstrated that its biological function was oxidizing hydroxyl groups of PVA 1799 to form diketone, and PVA 1799 could be degraded completely by successive treatment with mPVADH and oxidized PVA hydrolase (OPH).
研究领域:
生物技术
·
酶学
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环境生物技术
·
蛋白质工程
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高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2025
·
IF 11.3
Guoqiang Zhao,Wenjing Chen,Rongrong Zhang,Rui Zhang,Bo Jiang,Ruyan Hou,Xing Huang
Cypermethrin, a common pyrethroid insecticide, raises significant ecological concerns due to its widespread use. In this study, a highly efficient cypermethrin-degrading strain, Rhodococcus sp. H-3, was isolated. The strain was capable of degrading 30 mg/L cypermethrin at the rate of 83.48 % within 7 days and it could hydrolyze cypermethrin into 3-phenoxybenzoic acid (3-PBA) and permethric acid (DCVA). A novel cypermethrin degradation gene, cymE1 , was identified in strain H-3 through genome analysis, and its highest level of amino acid sequence similarity observed was 33.50 % in the Swiss-Prot database. The functional strain, SCK6-E, which could secrete CymE1, was successfully constructed by using double-exchange strategies. Strain SCK6-E could be applied for the removal of cypermethrin residues from tea plant leaves with a removal rate of 57.83 % within 2 h. Furthermore, strain H-3 demonstrated the capability to remediate cypermethrin-contaminated soil, exhibiting a degradation rate of 65.80 % over 10 days. The results of the 16S rRNA high-throughput sequencing indicated that strain H-3 was conducive to the restoration of the diversity and richness of the bacterial community in the soil. This study provides novel strain and gene resources for researching the degradation mechanism of pyrethroids, and offers valuable insights for developing effective pesticide residue remediation strategies.
研究领域:
环境微生物学
·
生物修复
·
基因组学
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分子生物学
·
农业科学
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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
·
微生物学
·
生物修复
·
生物技术
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PubMed
高影响因子
WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY
·
2024
·Vol. 40
·期 6
·1-13
·
IF 4
Zhao Siji,Yin Ruya,Zhang Mengwei,Zhai Ziqi,Shen Zhen,Mou Yan,Xu Dan,Zhou Ligang,Lai Daowan
The endophytic fungus Berkleasmium sp. Dzf12 that was isolated from Dioscorea zingiberensis , is a proficient producer of palmarumycins, which are intriguing polyketides of the spirobisnaphthalene class. These compounds displayed a wide range of bioactivities, including antibacterial, antifungal, and cytotoxic activities. However, conventional genetic manipulation of Berkleasmium sp. Dzf12 is difficult and inefficient, partially due to the slow-growing, non-sporulating, and highly pigmented behavior of this fungus. Herein, we developed a CRISPR/Cas9 system suitable for gene editing in Berkleasmium sp. Dzf12. The protoplast preparation was optimized, and the expression of Cas9 in Berkleasmium sp. Dzf12 was validated. To assess the gene disruption efficiency, a putative 1, 3, 6, 8-tetrahydroxynaphthalene synthase encoding gene, bdpks , involved in 1,8-dihydroxynaphthalene (DHN)-melanin biosynthesis, was selected as the target for gene disruption. Various endogenous sgRNA promoters were tested, and different strategies to express sgRNA were compared, resulting in the construction of an optimal system using the U6 snRNA-1 promoter as the sgRNA promoter. Successful disruption of bdpks led to a complete abolishment of the production of spirobisnaphthalenes and melanin. This work establishes a useful gene targeting disruption system for exploration of gene functions in Berkleasmium sp. Dzf12, and also provides an example for developing an efficient CRISPR/Cas9 system to the fungi that are difficult to manipulate using conventional genetic tools.
研究领域:
分子生物学
·
真菌遗传学
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生物技术
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植物化学
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DOI
PubMed
高影响因子
JOURNAL OF APPLIED PHYCOLOGY
·
2023
·
IF 3.3
Tang Tiancheng,Li Chen,Zhu Benwei,Yao Zhong
Ulvan lyase is a useful tool which can degrade ulvan into oligosaccharides with a range of biological activities. In this study, the ulvan lyase ULA-3 from Alteromonas sp. 76–1, which was a 1467-bp encoded 489-amino acid residue protein, has been cloned, heterologously expressed and biochemically characterized. ULA-3 showed the maximum activity at 45 ˚C and pH 9.0. The K m is 1.879 mg mL −1 and V max is 2.597 µmol min −1 mL −1 . Its enzyme activity was outstanding at 11.754 U mg −1 . Moreover, its metal ion stability is exceptionally good and most metal ions at a concentration of 1 mM have no inhibitory effect on its activity. It can endolytically degrade ulvan into oligosaccharides with a degree of polymerization (Dp) of 2–4 and with unsaturated double bond through the β -elimination reaction, which mainly cleaves the glycosidic bond between rhamnose and uronic acids. All in all, our study has increased the ulvan lyase database and offers the opportunity to fully utilize ulvan, a green biomass resource from marine algae.
研究领域:
生物化学
·
生物技术
·
海洋生物学
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DOI
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
·
生物降解
·
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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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）