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期刊论文 5

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2020 2

2019 1

2017 1

2013 1

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微生物代谢 1

甘油 1

生物修复 1

生物表面活性剂 1

生物转化 1

生物降解 1

鼠李糖脂 1

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Biosorption and biotransformation of crystal violet by

Tao PAN, Suizhou REN, Jun GUO, Meiying XU, Guoping SUN

《环境科学与工程前沿（英文）》 2013年 第7卷 第2期   页码 185-190 doi: 10.1007/s11783-012-0435-6

摘要： DN322p, an offspring of DN322, has the capacity to adsorb and decolorize triphenylmethane dyes in wastewater simultaneously. As a common triphenylmethane dye, crystal violet (CV) was chosen to test the decolorization characteristics of DN322p. Within 0.5 h, the strain DN322p adsorbed a large amount of CV, producing a deep-colored cell pellet and colorless supernatant. The colors of the cell pellet and supernatant lightened over time. The supernatant and dichloromethane extract of the cell pellet both showed conspicuous CV and leuco CV (LCV) characteristic absorbance peaks at 590 nm and 260 nm, respectively, in the UV-vis spectral analysis. This finding indicated that the DN322p cells can adsorb the two dyes. A 99% (w/w) decolorization rate was achieved within 2.5 h with shaking at 30°C for 50 mg CV·L . High Performance Liquid Chromatography (HPLC) analysis of the dichloromethane extract of the supernatant and cell pellet confirmed that CV was mainly converted into its leuco form. Dead cells had a similar adsorption capacity with living cells. About 90% of CV in the dye solution (50 mg·L ) was removed by autoclaved cells with an optical delnsity at 600 nm (OD ) above 1.0.

关键词： crystal violet     decolorization     biosorption     biotransformation     Aeromonas hydrophila DN322p    

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Microbial mediated arsenic biotransformation in wetlands

Si-Yu Zhang, Paul N. Williams, Jinming Luo, Yong-Guan Zhu

《环境科学与工程前沿（英文）》 2017年 第11卷 第1期 doi: 10.1007/s11783-017-0893-y

摘要： Distribution and behavior of arsenic in wetland are summarized. Macro-scale and micro-scale processes in wetland are reviewed. Microbes act as the switch in determining wetland as a source or sink of arsenic. Environmental factors affecting arsenic microbial biotransformation are summarized. Arsenic (As) is a pervasive environmental toxin and carcinogenic metalloid. It ranks at the top of the US priority List of Hazardous Substances and causes worldwide human health problems. Wetlands, including natural and artificial ecosystems (i.e. paddy soils) are highly susceptible to As enrichment; acting not only as repositories for water but a host of other elemental/chemical moieties. While macro-scale processes (physical and geological) supply As to wetlands, it is the micro-scale biogeochemistry that regulates the fluxes of As and other trace elements from the semi-terrestrial to neighboring plant/aquatic/atmospheric compartments. Among these fine-scale events, microbial mediated As biotransformations contribute most to the element’s changing forms, acting as the ‘switch’ in defining a wetland as either a source or sink of As. Much of our understanding of these important microbial catalyzed reactions follows relatively recent scientific discoveries. Here we document some of these key advances, with focuses on the implications that wetlands and their microbial mediated transformation pathways have on the global As cycle, the chemistries of microbial mediated As oxidation, reduction and methylation, and future research priorities areas.

关键词： Arsenic     Wetland     Microbes     Switch    

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A newly defined dioxygenase system from Mycobacterium vanbaalenii PYR-1 endowed with an enhanced activity of dihydroxylation of high-molecular-weight polyaromatic hydrocarbons

Yiquan Wu, Ying Xu, Ningyi Zhou

《环境科学与工程前沿（英文）》 2020年 第14卷 第1期 doi: 10.1007/s11783-019-1193-5

摘要： • Mycobacterium vanbaalenii PYR-1 utilizes PAHs at different rates. • Both NidA3B3 and FNidA3B3 catalyze high-molecular-weight PAHs dihydroxylation. • NidA3B3 shows an enhanced activity with an endogenous electron transport chain. • FNidA3B3 has an enhanced activity by 50% approximately compared with NidA3B3. • FNidA3B3/NidA3B3 and NidAB in the same strain come from different ancestors. NidA3B3 is a terminal dioxygenase whose favorable substrates are high-molecular-weight polyaromatic hydrocarbons (PAHs) from Mycobacterium vanbaalenii PYR-1, a powerful PAHs degradation strain. NidA3B3 was reported to incorporate a dioxygen into the benzene ring of PAHs when equipped with an exogenous electron transport chain components PhdCD from Nocardioides sp. strain KP7 by biotransformation, but this enzyme system was not particularly efficient. In this study, strain PYR-1 was confirmed to utilize four different PAHs at different growth rates. When PhtAcAd, an endogenous electron transport chain of a phthalate dioxygenase system, was substituted for PhdCD to couple with NidA3B3, the specific activity to convert phenanthrene by strain BL21(DE3) [pNidA3B3-PhAcAd] was 0.15±0.03 U/mg, but the specific activity of strain BL21(DE3) [pNidA3B3-PhdCD] was only 0.025±0.006 U/mg. In addition, FNidA3, encoded by a newly defined ORF, has a prolonged 19-amino acid sequence at the N-terminal compared with NidA3. FNidA3B3 increased the activity by 50% approximately than NidA3B3 when using PhtAcAd. Components of the electron transport chain PhtAc and PhtAd were purified and characterized. The Km, kcat, kcat/Km values of the PhtAd were 123±26.9 M, 503±49.9 min−1, 4.1 M−1·min−1, respectively. And the Km, kcat, kcat/Km values of the ferredoxin PhtAc were 52.5±9.7 M, 3.8±0.19 min−1 and 0.07 M−1·min−1, respectively. Basing on the phylogenetic analysis, NidA3/FNidA3 were far from its isoenzyme NidA from the same strain. Combining their primary differences of transcriptional pattern in vivo, it indicated that the functionally similar Rieske dioxygenases NidA3B3/FNidA3B3 and NidAB might originate from different ancestors.

关键词： Biodegradation     polyaromatic hydrocarbons     biotransformation     ring-hydroxylating dioxygenase system    

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甘油诱导的鼠李糖脂增强伯克霍尔德菌属C3中二苯并噻吩的生物降解 Article

Camila A. Ortega Ramirez, Abraham Kwan, Qing X. Li

《工程（英文）》 2020年 第6卷 第5期   页码 533-540 doi: 10.1016/j.eng.2020.01.006

摘要：

在高度城市化的地区，人为活动造成的污染损害了土地的完整性，减少了农业耕作的土壤利用率。二苯并噻吩（DBT）是一种城市地区常见的杂环芳香烃，常被用作污染物微生物转化研究的模型化合物。人体接触的可能性及其健康风险使DBT成为一种令人担忧的化学品，因此，需要对DBT进行环境管理。利用甘油刺激伯克霍尔德菌属C3（Burkholderia sp. C3），降解其中的DBT，内容涉及以下方面：①DBT的生物降解动力学；②细菌生长；③鼠李糖脂（RL）的生物合成；④RL分泌。在甘油与DBT最佳摩尔比的情况下，实验第1天，DBT的生物降解速率常数与单独使用DBT培养基相比提高了18倍，DBT的生物降解率提高了25％~30%。这种增长变化与细菌生长加快和RL生物合成反应的增强有关。蛋白质组学研究揭示了参与RL生物合成作用的上级和主要阶段的酶类。在增添了甘油和DBT的培养基中鉴定出了鼠李糖脂的同系物：Rha-C10-C10、Rha-Rha-C10-C10、Rha-Rha-C10-C12和Rha-Rha-C12-C12，然而，在不含甘油或添加了RL抑制剂的培养物中只鉴定出Rha-C12-C12。研究表明，甘油通过促进RL的合成和细菌的生长来促进DBT的生物降解。根据这些结果，值得进一步研究甘油对环境生物的刺激作用，以促进生物修复技术的发展和提高农业土壤的有效性。

关键词： 生物降解     生物修复     生物表面活性剂     生物转化     甘油     微生物代谢     鼠李糖脂    

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Construction of a CaHPO4-PGUS1 hybrid nanoflower through protein-inorganic self-assembly, and its application in glycyrrhetinic acid 3-O-mono-β-D-glucuronide preparation

Tian Jiang, Yuhui Hou, Tengjiang Zhang, Xudong Feng, Chun Li

《化学科学与工程前沿（英文）》 2019年 第13卷 第3期   页码 554-562 doi: 10.1007/s11705-019-1834-z

摘要： Glycyrrhetinic acid 3- -mono- -D-glucuronide (GAMG), an important pharmaceutical intermediate and functional sweetener, has broad applications in the food and medical industries. A green and cost-effective method for its preparation is highly desired. Using site-directed mutagenesis, we previously obtained a variant of -glucuronidase from Li-3 (PGUS1), which can specifically transform glycyrrhizin (GL) into GAMG. In this study, a facile method was established to prepare a CaHPO -PGUS1 hybrid nanoflower for enzyme immobilization, based on protein-inorganic hybrid self-assembly. Under optimal conditions, 1.2 mg of a CaHPO -PGUS1 hybrid nanoflower precipitate with 71.2% immobilization efficiency, 35.60 mg∙g loading capacity, and 118% relative activity was obtained. Confocal laser scanning microscope and scanning electron microscope results showed that the enzyme was encapsulated in the CaHPO -PGUS1 hybrid nanoflower. Moreover, the thermostability of the CaHPO -PGUS1 hybrid nanoflower at 55°C was improved, and its half-life increased by 1.3 folds. Additionally, the CaHPO -PGUS1 hybrid nanoflower was used for the preparation of GAMG through GL hydrolysis, with the conversion rate of 92% in 8 h, and after eight consecutive runs, it had 60% of its original activity.

关键词： β-glucuronidase     enzyme-inorganic hybrid nanoflower     biotransformation     glycyrrhizin     glycyrrtinic acid 3-O-mono-β-D-glucuronide    

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标题 作者 时间 类型 操作

Biosorption and biotransformation of crystal violet by

Tao PAN, Suizhou REN, Jun GUO, Meiying XU, Guoping SUN

期刊论文

Microbial mediated arsenic biotransformation in wetlands

Si-Yu Zhang, Paul N. Williams, Jinming Luo, Yong-Guan Zhu

期刊论文

A newly defined dioxygenase system from Mycobacterium vanbaalenii PYR-1 endowed with an enhanced activity of dihydroxylation of high-molecular-weight polyaromatic hydrocarbons

Yiquan Wu, Ying Xu, Ningyi Zhou

期刊论文

甘油诱导的鼠李糖脂增强伯克霍尔德菌属C3中二苯并噻吩的生物降解

Camila A. Ortega Ramirez, Abraham Kwan, Qing X. Li

期刊论文

Construction of a CaHPO4-PGUS1 hybrid nanoflower through protein-inorganic self-assembly, and its application in glycyrrhetinic acid 3-O-mono-β-D-glucuronide preparation

Tian Jiang, Yuhui Hou, Tengjiang Zhang, Xudong Feng, Chun Li

期刊论文