APPLIED AND ENVIRONMENTAL MICROBIOLOGY
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2023
·Vol. 89
·期 3
·
IF 4.4
Ling Wang,Xiaowei Wu,Chenghua Gao,Lingrui Wei,Qian Li,Aitao Li
In this study, a new cytochrome P450 enzyme, namely, CYP68J5_Fusarium graminearum (CYP68J5_fg), was identified from Fusarium graminearum via a combination of transcriptome sequencing and heterologous expression in Saccharomyces cerevisiae. The biotransformation of progesterone by whole-cells of S. cerevisiae expressing CYP68J5_fg revealed that the CYP68J5_fg possessed steroidal 12β- and 15α-hydroxylase activities. To the best of our knowledge, this is the first time that a fungal P450 enzyme with 12β-hydroxylase activity has been identified. This advance offers opportunities to boost the efficiency and selectivity of the CYP68J5_fg hydroxylating system and thus shows great potential for further applications of this enzyme for the synthesis of steroid drugs.IMPORTANCE Regioselective and stereoselective hydroxylation is of vital importance in the functionalization of steroids, which remains challenging in organic synthesis. In particular, the C12-hydroxy steroids play a significant role in the synthesis of many important steroidal drugs. In this study, a novel fungal P450 enzyme with 12β-hydroxylation activity was identified, and it shows different substrate specificity and regioselectivity, compared to the bacterial and fungal steroidal hydroxylases that are known to date. This lays the foundation for the creation of effective biocatalysts for the process of 12β-hydroxylation, although further understanding of the molecular structural basis of this fungal P450 is needed to facilitate the engineering of this enzyme for industrial applications.
研究领域:
生物化学
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酶学
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药学
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微生物学
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产品关联
DOI
PubMed
高影响因子
Catalysts
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2016
·Vol. 6
·期 5
·74
·
IF 2.964
Yongli Dong,Xiaoyu Niu,Weina Song,Dong Wang,Liqiang Chen,Fulong Yuan,Yujun Zhu
The vanadium oxide/reduced graphene oxide (VOx/RGO) composites have been prepared by a simple solvothermal method with the assistance of cationic surfactant cetyltrimethylammonium bromide (CTAB). The microstructure and morphology of the resultant VOx/RGO composites have been well characterized. The VOxnanoparticles are highly dispersed on the RGO sheets with a particle size of about 25 nm. When used as hydroxylation catalysts, the VOx/RGO composites are more efficient than individual RGO and vanadium oxide catalysts. The enhanced catalytic performance may be related to not only the well dispersed VOxactive species, but also the hydrophobic surface and huge π-electron system of RGO for the adsorption and activation of benzene. In addition, the effects of calcination conditions on the microstructure and catalytic properties of VOx/RGO composites have also been investigated. The uniform VOxnanoparticles on the separated RGO sheets show highly efficient catalytic performance, while the formation of aggregated HxV2O5and bulk V2O5species along with the destruction of RGO sheets are poor for the hydroxylation of benzene. Up to 17.4% yield of phenol is achieved under the optimized catalytic reaction conditions.Keywords:vanadium oxide;reduced graphene oxide;benzene;hydroxylation;phenol
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
高影响因子
INTERNATIONAL BIODETERIORATION & BIODEGRADATION
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2023
·
IF 4.8
Ni-Hong Yao,Xi Liu,Chenyang Luo,Lei Zou,Jinhua Li,Jing Chen,Dazhong Yan,Hong-Jun Chao
The compound m -cresol ( meta -cresol) is an important representative of alkylphenol pollutants with high toxicity and potential carcinogenicity . The genes and enzymes associated with the m -cresol pathway have not yet been well elucidated. In this study, Comamonas thiooxydans CHJ601 was isolated from industrial wastewater and cultured utilizing m -cresol as the sole source of carbon and energy. m -Cresol catabolism begins with the oxidation of its methyl group in strain CHJ601. Genome sequencing and heterologous expression of key genes revealed its detailed catabolic pathway. m -Cresol methylhydroxylase (MchAB) catalyzed o -cresol ( ortho -cresol), m -cresol, and p -cresol ( para -cresol) in the presence of NADH and FAD. The K m value of m -cresol (48.74 ± 5.02 μM) for MchAB was much lower than that of o -cresol (747.80 ± 53.34 μM) and p -cresol (541.90 ± 41.43 μM). Molecular docking analysis showed that the binding affinities of MchAB against m -cresol with two hydrogen bonds are higher than p -cresol methylhydroxylase with one. The optimal substrate of MchAB was m -cresol, which can be catalyzed into 3-hydroxybenzyl alcohol and then oxidized to 3-hydroxybenzaldehyde. The mchC gene encoded 3-hydroxybenzaldehyde dehydrogenase , which catalyzes the oxidation of 3-hydroxybenzaldehyde to 3-hydroxybenzoate. The results indicated that MchAB and MchC are the first characterized enzymes to catalyze the oxidation of the meta -methyl group of m -cresol in the strain CHJ601.
研究领域:
环境微生物学
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分子生物学
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生物化学
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DOI
高影响因子
ACS Applied Nano Materials
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2024
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IF 5.3
Jianshuai Mu,Aizhu Peng,Xinran Wang,Jin Wang,Zengjiao Hong,Danna Guo,Shulai Lei,Jiajun Wang,En-Cui Yang
Designing low-cost and environmentally friendly oxygen evolution reaction (OER) electrocatalysts to enhance the electrocatalytic water decomposition to produce hydrogen still faces great challenges. In this work, a feasible strategy for metallic/nonmetallic elements co-doping to boost the OER catalytic properties of iron oxyhydroxide is proposed. A series of S and Cr co-doped iron oxyhydroxides nanoarrays loaded on nickel foam (Sx,Cr-FeOOH/NF) were prepared by an electrodeposition–hydrothermal method. The optimized S0.1,Cr-FeOOH/NF exhibits a superior electrocatalytic OER performance with low overpotential (235 mV at 100 mA cm–2), highly outperforming commercial RuO2. Meanwhile, the overpotential of S0.1,Cr-FeOOH/NF increases by only 4 mV after 70 h of stability testing at 100 mA cm–2, demonstrating its durability. The nanoarray with ultrathin nanosheets of S0.1,Cr-FeOOH/NF regulated by S and Cr co-doping can offer abundant active sites and also facilitate mass transportation. The density functional theory (DFT) calculation results show that S and Cr co-doping modifies the electronic structure of S0.1,Cr-FeOOH/NF, which thus optimizes the adsorption energy toward the OER intermediates, promotes the transformation of *O to *OOH (rate-determining step), and thus accelerates the OER kinetics.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
RSC Advances
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2021
·Vol. 11
·期 57
·36166-36173
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IF 3.361
Lixiao Han,Cong Peng,Jinming Huang,Shengyao Wang,Xiaohu Zhang,Hao Chen,Yi Yang
Planting highly efficient and low-cost Ni-based noble-metal-free active sites on semiconductors is of great significance in the field of photocatalysis. Herein, taking wide visible-light-responsive 2D C3N5 as a model semiconductor, an impressive near-zero-cost 2D S-doped nickel hydroxide (S–Ni(OH)2) is grown on C3N5 ultrafast within 30 min under ambient conditions by facile reaction between extremely low-cost Ni(NO3)2 and Na2S in aqueous solution. The fabricated 2D S–Ni(OH)2–C3N5 hybrid exhibits enhanced photocatalytic performance for both H2 production from water and NO removal for air purification. The H2 production rate on S–Ni(OH)2–C3N5 is ∼7 times higher than that of Ni(OH)2–C3N5 and even slightly higher than that of Pt–C3N5, demonstrating its potential as a candidate for noble metal catalysts like Pt. In particular, an apparent quantum yield (AQY) value of 30.9% at 420 nm for H2 production is reached on 1.0 wt% S–Ni(OH)2–C3N5 due to quick internal charge transfer efficiency. In addition, ∼42% of NO can be purified in a continuous flow reaction system. This work affords a cost-efficient strategy to steer the photocatalytic property of Ni-based catalysts.
研究领域:
材料科学
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环境科学
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化学
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DOI
PubMed
高影响因子
DRUG METABOLISM AND DISPOSITION
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2024
·Vol. 52
·期 11
·1234-1243
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IF 4.4
Yutong Wang,Yixuan Wang,YiTing Hu,QingLiang Wu,Lanlan Gui,Wushuang Zeng,Qi Chen,Tingting Yu,Xinjie Zhang,Ke Lan
Sterol 12α-hydroxylase (CYP8B1) is the unique P450 enzyme with sterol 12-oxidation activity, playing an exclusive role in 12α-hydroxylating intermediates along the bile acid (BA) synthesis pathway. Despite the long history of BA metabolism studies, it is unclear whether CYP8B1 catalyzes 12α-hydroxylation of C27 BAs, the key intermediates shuttling between mitochondria and peroxisomes. This work provides robust in vitro evidence that both microsomal and recombinant CYP8B1 enzymes catalyze the 12α-hydroxylation of dihydroxycoprostanic acid (DHCA) into trihydroxycoprostanic acid (THCA). On the one hand, DHCA 12α-hydroxylation reactivity is conservatively detected in liver microsomes of both human and preclinical animals. The reactivity of human tissue fractions conforms well with the selectivity of CYP8B1 mRNA expression, while the contribution of P450 enzymes other than CYP8B1 is excluded by reaction phenotyping in commercial recombinant enzymes. On the other hand, we prepared functional recombinant human CYP8B1 proteins according to a recently published protocol. Titration of the purified CYP8B1 proteins with either C4 (7α-hydroxy-4-cholesten-3-one) or DHCA yields expected blue shifts of the heme Soret peak (type I binding). The recombinant CYP8B1 proteins efficiently catalyze 12α-hydroxylation of both DHCA and C4, with substrate concentration occupying half of the binding sites of 3.0 and 1.9 μM and kcat of 3.2 and 2.6 minutes−1, respectively. In summary, the confirmed role of CYP8B1 in 12α-hydroxylation of C27 BAs has furnished the forgotten passageway in the BA synthesis pathway. The present finding might have opened a new window to consider the biology of CYP8B1 in glucolipid metabolism and to evaluate CYP8B1 inhibition as a therapeutic approach of crucial interest for metabolic diseases.
研究领域:
生物化学
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分子生物学
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药理学
✓ 已验证
DOI
PubMed
高影响因子
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
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2025
·
IF 4.6
Ze-Feng Xu,Chuan-Wu Chen,Ya-Nan Jing,Da-Qiang Liu,Lei-Lei Li,Xing-Liang Yin
Iron(III) oxyhydroxide (FeOOH) is a highly promising non-precious metal oxygen evolution reaction (OER) catalyst due to its abundance, cost-effectiveness, and favorable electrochemical characteristics. Nevertheless, its low electrical conductivity and sluggish OER kinetics pose significant challenges for practical applications. OER typically occurs through the adsorbed evolution mechanism (AEM), involving multiple proton-coupled electron transfer steps with higher theoretical overpotential requirements. In contrast, the lattice oxygen mechanism (LOM) facilitates oxygen generation through direct coupling of the O−O bond, potentially circumventing the thermodynamic constraints inherent in AEM. In this study, an effective ion exchange between small-sized anions with large dipole moments and chloride ions residing within the tunnels of β-FeOOH was successfully achieved through phase-induced oxygen defect engineering. The experimental findings demonstrate that the synthesized α/β-FeOOH with high-density oxygen vacancy (O V ) exhibits enhanced lattice oxygen redox reactivity, expedited OER kinetics, and reduced thermodynamic barriers. Those improvements are ascribed to the activation of lattice oxygen within FeOOH, which has triggered a transition in its OER mechanism from AEM to LOM. Further investigations suggest that elevated reaction temperatures, within an appropriate range, foster ion exchange in β-FeOOH channels and actively encourage the creation of O V in FeOOH. That dynamic behavior transition of FeOOH enables it to overcome the inherent thermodynamic limitations of the AEM, resulting in a remarkable enhancement of its intrinsic OER activity. Remarkably, this improvement is achieved without relying on additional co-catalysts, which is expected to promote the understanding of intrinsic kinetic alterations in FeOOH electrocatalysts.
研究领域:
材料科学
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电化学
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能源科学
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产品关联
DOI
高影响因子
Frontiers in Microbiology
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2018
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IF 4.019
Chen Xin,Tang Hongzhi,Liu Yongdi,Xu Ping,Xue Yong,Lin Kuangfei,Cui Changzheng
3-Hydroxybenzoate 6-hydroxylase, an NADH-dependent flavoprotein, can convert 3-hydroxybenzoate which is an important intermediate in the biodegradation of many aromatic hydrocarbons. 3-Hydroxybenzoate is metabolized by entering the TCA cycle through the gentisate pathway. We found a putative 3HB6H gene from a cluster that potentially encodes for gentisic acid degradation from a halophilic Martelella sp. strain AD-3. The corresponding protein was expressed with an N-terminal His-tag and purified by Ni2+-nitrilotriacetic acid affinity chromatography. The protein showed an overexpressed band of about 46 kDa by SDS–PAGE, and it was also proven that the enzyme contains FAD by absorption spectroscopy and HPLC analysis. The optimal activity of 3HB6H from strain AD-3 was observed in phosphate buffer (pH 8.0) at 37∘C without salinity (NaCl) and metal salts. The Km values of 3-hydroxybenzoate 6-hydroxylase were determined to be 72.6 ± 10.1 μM and 104.1 ± 18.2 μM for 400 μM NADH and 3-hydroxybenzoate, respectively. Site-directed mutagenesis showed that residues 305, 306 and 308 are important for FAD binding. In addition, we found that Tyr221 and Gln305 of 3HB6H from strain AD-3 are involved in substrate binding.
研究领域:
微生物学
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酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry B
·
2023
·Vol. 11
·期 47
·11235-11250
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IF 7
Chan Chen,Haisheng Ren,Weikang Tang,Mengqi Han,Qinfei Chen,Hong Zhou,Jiadong Chen,Yuyue Gao,Wenbin Liu
L-3,4-Dihydroxyphenylalanine (L-DOPA) is widely used in Parkinson's disease treatment and is therefore in high demand. Development of an efficient method for the production of L-DOPA is urgently required. Nanozymes emulating tyrosine hydroxylase have attracted enormous attention for biomimetic synthesis of L-DOPA, but suffered from heterogeneity. Herein, a spherical porous iron–nitrogen–carbon nanozyme was developed for production of L-DOPA. Tannic acid chelated with ferrous ions to form a tannin-iron coordination framework as a carbon precursor. Iron and nitrogen co-doped carbon nanospheres were assembled via an evaporation-induced self-assembly process using urea as a nitrogen source, F127 as a soft template, and formaldehyde as a crosslinker. The nanozyme was obtained after carbonization and acid etching. The nanozyme possessed a dispersive iron atom anchored in the Fe–N coordination structure as an active site to mimic the active center of tyrosine hydroxylase. The material showed spherical morphology, uniform size, high specific surface area, a mesoporous structure and easy magnetic separation. The structural properties could promote the density and accessibility of active sites and facilitate mass transport and electron transfer. The nanozyme exhibited high activity to catalyze the hydroxylation of tyrosine to L-DOPA as tyrosine hydroxylase in the presence of ascorbic acid and hydrogen peroxide. The titer of DOPA reached 1.2 mM. The nanozyme showed good reusability and comparable enzyme kinetics to tyrosine hydroxylase with a Michaelis–Menten constant of 2.3 mM. The major active species was the hydroxyl radical. Biomimetic simulation of tyrosine hydroxylase using a nanozyme with a fine structure provided a new route for the efficient production of L-DOPA.
研究领域:
生物化学
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材料科学
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医学
✓ 已验证
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
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2020
·
IF 6.215
Ran Duan,Yejun Li,Shen Gong,Yonggang Tong,Zhou Li,Weihong Qi
The development of industrial application of water splitting demands simple and effective methods for the preparation of highly efficient electrocatalysts that are inexpensive and robust. Herein, we report a simple activation method to decorate 3D cobalt iron oxyhydroxide (CoFe-OOH) nanosheets on Co 2 P nanoparticles with Ni foams (NF) as substrates. The synthesized catalysts exhibit excellent activity for electrochemical oxygen evolution reaction due to the hierarchical heterostructures and synergistic effects of CoFe-OOH and Co 2 P. The as-prepared catalysts require a low overpotential of 199 mV to deliver 30 mA cm −2 in oxygen evolution reaction in 1 M KOH with a small Tafel slope of 39 mV dec −1 , indicating favorable kinetics during electrolysis. The synthesized catalysts are further used as cathode and anode for overall water splitting, which only requires a cell voltage of 1.60 V at a current density of 30 mA cm −2 . This work provides new insights on the preparation of efficient electrocatalysts for overall water splitting, which may have the potentials for industrial water electrolysis.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
·
2019
·Vol. 85
·期 23
·
IF 4.077
Bingbing Ma,Qianwen Wang,Haruo Ikeda,Chunfang Zhang,Lian-Hua Xu
Our previous study showed that CYP105D7, a substrate-promiscuous P450, catalyzes the hydroxylation of 1-deoxypentalenic acid, diclofenac, naringenin, and compactin. In this study, 14 steroid compounds were screened using recombinant Escherichia coli cells harboring genes encoding CYP105D7 and redox partners (Pdx/Pdr, RhFRED, and FdxH/FprD), and the screening identified steroid A-ring 2β- and D-ring 16β-hydroxylation activity. Wild-type CYP105D7 was able to catalyze the hydroxylation of five steroids (testosterone, progesterone, 4-androstene-3,17-dione, adrenosterone, and cortisone) with low (<10%) conversion rates. Structure-guided site-directed mutagenesis of arginine residues around the substrate entrance and active site showed that the R70A and R190A single mutants and an R70A/R190A double mutant exhibited greatly enhanced conversion rates for steroid hydroxylation. For the conversion of testosterone in particular, the R70A/R190A mutant's kcat/Km values increased 1.35-fold and the in vivo conversion rates increased significantly by almost 9-fold with high regio- and stereoselectivity. Molecular docking analysis revealed that when Arg70 and Arg190 were replaced with alanine, the volume of the substrate access and binding pocket increased 1.08-fold, which might facilitate improvement of the hydroxylation efficiency of steroids.IMPORTANCE Cytochrome P450 monooxygenases (P450s) are able to introduce oxygen atoms into nonreactive hydrocarbon compounds under mild conditions, thereby offering significant advantages compared to chemical catalysts. Promiscuous P450s with broad substrate specificity and reaction diversity have significant potential for applications in various fields, including synthetic biology. The study of the function, molecular mechanisms, and rational engineering of substrate-promiscuous P450s from microbial sources is important to fulfill this potential. Here, we present a microbial substrate-promiscuous P450, CYP105D7, which can catalyze hydroxylation of steroids. The loss of the bulky side chains of Arg70 and Arg190 in the active site and substrate entrance resulted in an up to 9-fold increase in the substrate conversion rate. These findings will support future rational and semirational engineering of P450s for applications as biocatalysts.
研究领域:
生物化学
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合成生物学
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酶工程
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2022
·Vol. 38
·期 6
·1532-1541
·
IF 2.726
Zhang Tianran,Yu Huacheng,Wang Wenkai,Bai Pu,Jin Keyan,Zhang Jia-Nan,Yan Wenfu
It is highly desired yet challenged to find an adsorbent with low cost and excellent performance in the removal of organic dyes from aqueous solution. Here we reported that a layered cationic aluminum oxyhydroxide material hydrothermally synthesized from the low-cost source materials of AlCl 3 ·6H 2 O, CaO and H 2 O, known as JU-111, can meet such criterion in removing methyl orange(MO) and Congo red(CR). JU-111 shows fast adsorption kinetics[especially for CR(15 s)] and high adsorption capacity(MO: >1000 mg/g; CR: >2900 mg/g), surpassing most of the reported adsorbents. Comprehensive characterizations of the adsorption process of MO and CR revealed that both adsorptions were achieved via the anion exchange process. The characteristics of extremely low cost and excellent performance render JU-111 great potential in the practical applications in the removal of anionic dyes.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）