PROTEIN EXPRESSION AND PURIFICATION
·
2022
·
IF 2.025
Xiaowen Wang,Sibo Chen,Lin Fan,Hao Liu,Si Chen,Xianfeng Ye,Zhoukun Li,Zhongli Cui,Yan Huang
A new glycoside hydrolase family 2 (GH2) β-galactosidase encoding gene galM was cloned from Microvirga sp. strain MC18 and overexpressed in Escherichia coli . The recombinant β-galactosidase GalM showed optimal activity at pH 7.0 and 50 °C, with a stability at pH 6.0–9.0 and 20–40 °C, which are conditions suitable for the diary environment. The K m and V max values for o-nitrophenyl-β- d -galactopyranoside (oNPG) were 1.30 mmol/L and 15.974 μmol/(min·mg), respectively. GalM showed low product inhibition by galactose with a K i of 73.18 mM and high tolerance for glucose that 86.5% activity retained in the presence of 500 mM glucose. It was also stable and active in 20% of methanol, ethanol and isopropanol. In addition, the enzyme activity of GalM was activated significantly over 0–2 mol/L NaCl (1.6–4.3 fold). These favorable properties make GalM a potential candidate for the industrial application.
研究领域:
生物化学
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酶学
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生物技术
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DOI
PubMed
高影响因子
Frontiers in Microbiology
·
2022
·
IF 6.064
Chen Yan,Zhou Ning,Chen Xueman,Wei Guoguang,Zhang Alei,Chen Kequan,Ouyang Pingkai
In this study, a gene encoding β-N-acetylglucosaminidase, designated NAGaseA, was cloned from Chitinibacter sp. GC72 and subsequently functional expressed in Escherichia coli BL21 (DE3). NAGaseA contains a glycoside hydrolase family 20 catalytic domain that shows low identity with the corresponding domain of the well-characterized NAGases. The recombinant NAGaseA had a molecular mass of 92 kDa. Biochemical characterization of the purified NAGaseA revealed that the optimal reaction condition was at 40°C and pH 6.5, and exhibited great pH stability in the range of pH 6.5–9.5. The Vmax, Km, kcat, and kcat/Km of NAGaseA toward p-nitrophenyl-N-acetyl glucosaminide (pNP-GlcNAc) were 3333.33 μmol min–1 l–1, 39.99 μmol l–1, 4667.07 s–1, and 116.71 ml μmol–1 s–1, respectively. Analysis of the hydrolysis products of N-acetyl chitin oligosaccharides (N-Acetyl COSs) indicated that NAGaseA was capable of converting N-acetyl COSs ((GlcNAc)2–(GlcNAc)6) into GlcNAc with hydrolysis ability order: (GlcNAc)2 > (GlcNAc)3 > (GlcNAc)4 > (GlcNAc)5 > (GlcNAc)6. Moreover, NAGaseA could generate (GlcNAc)3–(GlcNAc)6 from (GlcNAc)2–(GlcNAc)5, respectively. These results showed that NAGaseA is a multifunctional NAGase with transglycosylation activity. In addition, significantly synergistic action was observed between NAGaseA and other sources of chitinases during hydrolysis of colloid chitin. Finally, 0.759, 0.481, and 0.986 g/l of GlcNAc with a purity of 96% were obtained using three different chitinase combinations, which were 1.61-, 2.36-, and 2.69-fold that of the GlcNAc production using the single chitinase. This observation indicated that NAGaseA could be a potential candidate enzyme in commercial GlcNAc production.
研究领域:
生物化学
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酶学
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生物技术
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DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2022
·
IF 10.753
Qilu Cheng,Linna Du,Ligen Xu,Yuhua Zhao,Junwei Ma,Hui Lin
Nonylphenol (NP) toxicity limits the improvements in its algal remediation efficiency. This study comprehensively investigated the performance and mechanism of NaHCO 3 -driving effects on NP-exposed algae. The results showed that NaHCO 3 enhanced algal resistance to NP and the corresponding EC 50 values increased 1.31–4.25 times. Further, the toxicological effects of NP reduced with increasing pyrenoid volume and chlorophyll and carotenoids production, and decreasing cellular damage degree. Moreover, the concentration of extracellular polymeric substances was enhanced and more NP adsorption sites were formed. Consistently, RNA-seq demonstrated significant expression alterations in genes related to energy metabolism, cellular synthesis, photosynthesis, and carbon fixation. Besides, NP biodegradation rate was increased by 15.2 % and 11.1 % in the 1, and 4 mg/L NP treatments, respectively. Identification of degradation intermediates and their toxicity via Ecological Structure Activity Relationship program showed that NaHCO 3 accelerated sequential α-C removal from NP in algae with faster generation of less toxic metabolites, namely, 4-ethylphenol, 4-cresol and 4-hydroxybenzoic acid. This study provides new insights into the role of NaHCO 3 in toxicity alleviation and metabolism enhancement of NP in algae and can assist NP bioremediation efforts in aquatic environment.
研究领域:
环境科学
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水生毒理学
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生物修复
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Fermentation-Basel
·
2021
·Vol. 7
·期 4
·309
·
IF 3.975
Yiming Sun,Xiaowei Lin,Shaodong Zhu,Jianmeng Chen,Yi He,Yao Shi,Hua Liu,Lei Qin
The biotrickling filter (BTF) treatment is an effective way of dealing with air pollution caused by volatile organic compounds (VOCs). However, this approach is typically used for single VOCs treatment but not for the mixtures of VOC and volatile organic sulfur compounds (VOSCs), even if they are often encountered in industrial applications. Therefore, we investigated the performance of BTF for single and ternary mixture gas of dimethyl sulfide (DMS), propanethiol, and toluene, respectively. Results showed that the co-treatment enhanced the removal efficiency of toluene, but not of dimethyl sulfide or propanethiol. Maximum removal rates (rmax) of DMS, propanethiol and toluene were calculated to be 256.41 g·m−3·h−1, 204.08 g·m−3·h−1and 90.91 g·m−3·h−1, respectively. For a gas mixture of these three constituents,rmaxwas measured to be 114.94 g·m−3·h−1, 104.17 g·m−3·h−1and 99.01 g·m−3·h−1, separately. Illumina MiSeq sequencing analysis further indicated that Proteobacteria and Bacteroidetes were the major bacterial groups in BTF packing materials. A shift of bacterial community structure was observed during the biodegradation process.Keywords:biotrickling filter;decomposition;dimethyl sulfide;pollution;propanethiol;toluene
研究领域:
环境工程
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微生物学
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空气污染控制
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DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2024
·
IF 9.7
Yizhen Zhang,Yu-Cai He,Cuiluan Ma
Lignin is a plentiful and readily accessible renewable resource. Vanillylamine is a crucial raw material used to synthesize pharmaceuticals and high-value furan compounds that can be acquired by aminating lignin-derived vanillin (Van). However, effectually achieving the biocatalytic synthesis of vanillylamine has remained challenging. In this study, a dimethyl sulfoxide (DMSO)-H 2 O (1:9, vol/vol) bioreaction medium was constructed, and a recombinant E. coli ATA1012 carrying ω-transaminase from Caulobacter sp. D5 was used as the ω-transaminase biocatalyst to acquire the effectual biocatalytic synthesis of vanillylamine. Under optimized bioreaction conditions (37 ℃ and pH 7.5) by supplementary of isopropylamine (IPA) (Van/IPA = 1:5, mol/mol), 80–100 mM Van could be effectually converted by ATA1012 whole cells in DMSO-H 2 O (1:9, vol/vol) within 12 h, yielding 91.2 %–95.4 % vanillylamine, with >99 % selectivity. An efficient amination process was developed using ATA1012 with superior transaminase catalytic activity and substrate tolerance to effectively convert Van to vanillylamine in a DMSO-H 2 O medium.
研究领域:
生物技术
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生物化学
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有机化学
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药学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Kang Zhichao,Wang Tianye,Han Xuerong,Wang Chenxu,Zhang Shaoqing,Yu Hongwen
Corn planting is often associated with serious atrazine pollution and excessive corn straw amounts, causing severe threats to environmental and ecological security, as well as to green agricultural development. In this context, a Paenarthrobacter sp. KN0901 strain was applied to simultaneously remove atrazine and straw at low temperatures. The results of whole genome sequencing indicated that KN0901 encoded over nine straw biodegradation-related enzymes. In addition, 100% and 27.3% of atrazine and straw were simultaneously degraded by KN0901 following an incubation period of seven days at 15ºC and 180 rpm in darkness. The KN0901 strain maintained high atrazine and straw biodegradation rates under temperature and pH ranges of 4-25ºC and 5-9, respectively. The simultaneous atrazine and corn straw additions improved the microbial growth and biodegradation rates by increasing the functional gene expression level, cell viability, inner membrane permeability, and extracellular polymeric substance contents of KN0901. The hydroponic experiment results demonstrated the capability of the KN0901 strain to mitigate the toxicity of atrazine to soybeans in four days under the presence of corn straw. The present study provides a new perspective on the development of bioremediation approaches and their application to restore atrazine-polluted cornfields with large straw quantities, particularly in cold areas.
研究领域:
环境科学
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微生物学
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农业科学
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生物技术
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DOI
PubMed
高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2015
·Vol. 99
·期 11
·4629-4643
·
IF 3.337
Zhang Yan,Shi Junling,Gao Zhenhong,Yangwu Ruiming,Jiang Huanshi,Che Jinxin,Liu Yanlin
Phomopsis sp. XP-8 is an endophytic fungus that has the ability to produce pinoresinol diglucoside (PDG) in vitro and thus has potential application for the biosynthesis of PDG independent of plants. When cultivated in mung bean medium, PDG production was significantly improved and pinoresinol monoglucoside (PMG) and pinoresinol (Pin) were also found in the culture medium. In this experiment, starch, protein, and polysaccharides were isolated from mung beans and separately used as the sole substrate in order to explore the mechanism of fermentation and identify the major substrates that attributed to the biotransformation of PDG, PMG, and Pin. The production of PDG, PMG, and Pin was monitored using high-performance liquid chromatography (HPLC) and confirmed using HPLC-MS. Activities of related enzymes, including phenylalanine ammonia-lyase (PAL), trans-cinnamate 4-hydroxylase (C4H), and 4-coumarate-CoA ligase (4CL) were analyzed and tracked during the cultivation. The reaction system contained the compounds isolated from mung bean in the designed amount. Accumulation of phenylalanine, cinnamic acid, p-coumaric acid, PDG, PMG, and Pin and the activities of PAL, C4H, and 4CL were measured during the bioconversion. PMG was found only when mung bean polysaccharide was analyzed, while production of PDG and Pin were found when both polysaccharide and starch were analyzed. After examining the monosaccharide composition of the mung bean polysaccharide and the effect of the different monosaccharides had on the production of PMG, PDG, and Pin, galactose in mung bean polysaccharide proved to be the major factor that stimulates the production of PMG.
研究领域:
微生物学
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生物化学
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天然产物化学
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DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2019
·
IF 5.589
Zeyu Wang,Cong Chen,Huan Liu,Dzmitry Hrynshpan,Tatsiana Savitskaya,Jianmeng Chen,Jun Chen
The microbial reduction of nitrate in the presence of nanoscale zero-valent iron (nZVI) was evaluated to assess the feasibility of employing nZVI for biological denitrification treatment. The effect of modified nZVI on the growth, metabolism, and denitrification performance of Alcaligenes sp. TB under aerobic conditions was studied. Results showed that Alcaligenes sp. TB with nZVI/Pd had 31.5% increase in nitrate removal and 18.1% decrease in nitrite accumulation within 28 h. nZVI/Pd exhibited less inhibition on the cell growth (OD 600 = 0.725), NADH/NAD + ratio (86% of control), and electron transfer system activity (68.5% of control). In addition, nZVI/Pd decreased the membrane fluidity by increasing the trans/cis isomerization ratio (317.7% of control) to enhance the resistance of nZVI. This study underlines the effects of nZVI/Pd on membrane susceptibility via membrane fatty acid transformation during denitrification and suggests the influence of engineered nanomaterials on denitrification.
研究领域:
环境微生物学
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生物技术
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水处理
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产品关联
DOI
PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2019
·Vol. 190
·期 3
·826-838
·
IF 2.14
Liu Hang,Zhou Min,Ju Xin,Shu Hang,Hu Cuiying,Li Liangzhi
β-Glucosidase (BG) hydrolyzes cellobiose into glucose, and is a vital step in converting ionic liquids (ILs)-pretreated biomass to sustainable biofuels. The inactivation mechanism of BG from Paenibacillus sp. LLZ1 induced by microcrystalline cellulose was explored in various concentrations of ILs, composed of [Emim] + cation and [DEP] − , [OAc] − , [Br] − , [Cl] − , and [BF 4 ] − anions. The FTIR analysis of inactivated BG indicated that the ILs altered its β-sheet content. Moreover, circular dichroism spectroscopy (CD) suggested that the α-helix content decreased, while the β-sheet content increased with the presence of ILs in general. Interestingly, the secondary structure of BG had almost no change after [Emim]DEP treatment, while ionic liquid [Emim]BF 4 treatment caused the irreversible denaturation of BG. Eventually, by adding 0.4 mM of Aerosol OT surfactant, the BG activity was increased by 20.1% in the presence of 25% [Emim]DEP, and the corresponding glucose yield from hydrolysis of cellobiose was increased by 23.9%.
研究领域:
生物化学
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生物技术
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酶学
·
可持续能源
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DOI
PubMed
高影响因子
Microbial Biotechnology
·
2024
·Vol. 17
·期 2
·e14415
·
IF 4.8
Zhikuan Wang,Hailiang Qiu,Yulong Chen,Xuemin Chen,Chunhua Fu,Longjiang Yu
Green manufacture of steroid precursors from diosgenin by microbial replacing multistep chemical synthesis has been elusive. It is currently limited by the lack of strain and degradation mechanisms. Here, we demonstrated the feasibility of this process using a novel strain Mycolicibacterium sp. HK-90 with efficiency in diosgenin degradation. Diosgenin degradation by strain HK-90 involves the selective removal of 5,6-spiroketal structure, followed by the oxygenolytic cleavage of steroid nuclei. Bioinformatic analyses revealed the presence of two complete steroid catabolic gene clusters, SCG-1 and SCG-2, in the genome of strain HK-90. SCG-1 cluster was found to be involved in classic phytosterols or cholesterol catabolic pathway through the deletion of key kstD1 gene, which promoted the mutant m-∆kstD1 converting phytosterols to intermediate 9α-hydroxyandrostenedione (9-OHAD). Most impressively, global transcriptomics and characterization of key genes suggested SCG-2 as a potential gene cluster encoding diosgenin degradation. The gene inactivation of kstD2 in SCG-2 resulted in the conversion of diosgenin to 9-OHAD and 9,16-dihydroxy-pregn-4-ene-3,20-dione (9,16-(OH) 2 -PG) in mutant m-ΔkstD2 . Moreover, the engineered strain mHust-ΔkstD1,2,3 with a triple deletion of kstDs was constructed, which can stably accumulate 9-OHAD by metabolizing phytosterols, and accumulate 9-OHAD and 9,16-(OH) 2 -PG from diosgenin. Diosgenin catabolism in strain mHust-ΔkstD1,2,3 was revealed as a progression through diosgenone, 9,16-(OH) 2 -PG, and 9-OHAD to 9α-hydroxytestosterone (9-OHTS). So far, this work is the first report on genetically engineered strain metabolizing diosgenin to produce 21-carbon and 19-carbon steroids. This study presents a promising biosynthetic platform for the green production of steroid precursors, and provide insights into the complex biochemical mechanism of diosgenin catabolism.
研究领域:
生物技术
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微生物学
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生物化学
·
药学
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL RESEARCH
·
2023
·
IF 8.3
Tengfei Liu,Lixiao Ning,Chengyu Mei,Shuang Li,Lianbao Zheng,Pei Qiao,Haixia Wang,Tong Hu,Weihong Zhong
Dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), butyl benzyl phthalate (BBP), bis(2-ethylhexyl) phthalate (DEHP), and di-n-octyl phthalate (DOP) are hazardous chemicals listed as priority pollutants that disrupt endocrine systems. According to available reports, these six priority phthalate esters (PAEs) are considered the most polluting; however, no studies have been conducted on the efficient remediation of these PAEs. We therefore designed and constructed a synthetic bacterial consortium capable of the simultaneous and efficient degradation of six priority PAEs in minimal inorganic salt medium (MSM) and soil. The consortium comprised Glutamicibacter sp. ZJUTW, which demonstrates priority for degrading short-chain PAEs; Cupriavidus sp. LH1, which degrades phthalic acid (PA) and protocatechuic acid (PCA), intermediates of the PAE biodegradation process; and Gordonia sp. GZ-YC7, which efficiently degrades long-chain priority PAEs, including DEHP and DOP. In MSM containing the six mixed PAEs (250 mg/L each), the ZJUTW + YC + LH1 consortium completely degraded the four short-chain PAEs within 48 h, and DEHP (100%) and DOP (62.5%) within 72 h. In soil containing the six mixed PAEs (DMP, DEP, BBP, and DOP, 400 mg/kg each; DBP and DEHP, 500 mg/kg, each), the ZJUTW + YC + LH1 consortium completely degraded DMP, DEP, BBP, and DBP within 6 days, and 70.84% of DEHP and 66.24% of DOP within 2 weeks. The consortium efficiently degraded the six mixed PAEs in both MSM and soil. We thus believe that this synthetic microbial consortium is a strong candidate for the bioremediation of environments contaminated with mixed PAE pollutants.
研究领域:
环境科学
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微生物学
·
生物技术
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产品关联
DOI
PubMed
高影响因子
Arabian Journal of Chemistry
·
2022
·
IF 6.212
Xiaohong Yu,Mian Wang,Yiwen Zhang,Xiaochen Liu,Xiaoyang Zhang,Jinbin Liu,Dujun Wang,Wenbin Jin,Yongmei Lyu
The green and high-value recycling of shrimp shell and straw remains a worldwide problem. This study aimed to investigate the potential utilization of a fermentation broth (FB) which contains shrimp shell and straw as a new source for preparation of biodegradable films. Aureobasidium pullulans and Photobacterium sp. LYM-1 were used in the fermentation. The cellulase activity was 115.92 U/mL and chitinase activity was 17.89 U/mL in FB. The polysaccharides concentration in FB was 1.05 mg/mL after 7 days of fermentation. An eco-friendly PVA-reinforced FB biodegradable film (FBBF) was successfully prepared and the effect of different plasticizers and surfactants on the mechanical, structural, and impermeability properties of the film was determined. The formation of new bonds between PVA and FB was proved by FTIR spectroscopy. The FBBF containing 0.25 % ( w/v ) glycerol and 0.01 % ( v/v ) tween-20 showed better strength properties. Elongation and water-swelling properties were highly improved by adding 0.2 % ( m/v ) citric acid. According to FE-SEM images, the smooth and tight surface of citric acid added FBBF was observed. Interestingly, the FBBF film showed good heat/moisture capacity, antifungal, and degradation properties. This report reveals a new green, and high-value recycling of straw and shrimp shell by the co-fermentation with A. pullulans and Photobacterium sp. LYM-1. It is also a novel way for the preparation of biodegradable film.
研究领域:
生物技术
·
环境科学
·
材料科学
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微生物学
·
废物管理
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）