Frontiers in Chemistry
·
2022
·
IF 5.545
Fan Zhang,Changqing Mao,Siyu Cao,Runchi Zhang,Yi Guo,Guifang Chen,Chang Feng
Bio-nanomicelles based on biomaterials such as nucleic acids, peptides, glycans, and lipids have developed rapidly in the field of bioanalysis. Although DNA and peptides have unique advantages, unfortunately, there are few bio-nanomicelles integrating DNA with peptides. Here, we designed a peptide-DNA hybrid bio-nanomicelle for the activity detection of caspase-3. The detection mechanism is based on caspase-3 specific recognition and cleavage of peptide substrates, which owns high sensitivity and selectivity. Under optimal conditions, the detection of caspase-3 activity can be achieved using our designed bio-nanomicelles and the detection limit is 0.72 nM. Furthermore, the proposed method was also successfully applied for the detection of caspase-3 in cell lysate samples after apoptosis-inducing.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Molecular Catalysis
·
2022
·
IF 5.089
Yajiao Zhang,Minjie Liu,Huijing Wang,Juan Lin,Fener Chen
Non-catalytic sites are commonly present in many enzymes, but how to classify and modulate such sites for activity improvement is not well-explored. Herein a non-catalytic cavity in the 3-ketosteroid-Δ 1 -dehydrogenase (Δ 1 -KstD) from Mycobacterium smegmatis ( Ms KstD1), which could competitively bind to substrate to form non-catalytic complex, was predicted next to substrate tunnel by the CAVER/molecular dynamics. Based on that, a rational design was performed by Focused Site-directed Iterative Saturation Mutagenesis (FSISM) for blocking the non-catalytic cavity to enhance substrate enter active site to improve the Δ 1 -dehydrogenation activity of Ms KstD1. We obtained the best quadruple mutant (H132M\L113F\V419W\M51L) with 10-fold higher specific activity toward hydrocortisone than that of wild type enzyme. The Δ 1 -dehydrogenation space time yield toward hydrocortisone reached 36.0 g/L/h to produce prednisolone. This work displays how to combine focused mutagenesis with computational analysis to effectively identify and modify non-catalytic cavity to enhance enzyme activity for efficient production of Δ 1 -3-ketosteroid.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2022
·
IF 8.91
Kaidi Hu,Jianlong Li,Tianye Zhao,Qiao Zhou,Qin Li,Xinjie Hu,Guoquan Han,Shuhong Li,Likou Zou,Shuliang Liu
As a major intermediate metabolite of synthetic pyrethroids , the occurrence of 3-phenoxybenzoic acid hinders the decomposition of the parent pesticide and poses uncertain risks to environmental ecology and living organisms. Strain Aspergillus oryzae M-4 was previously reported to degrade 3-PBA and several substances were identified as downstream transformation products (TPs). But the mechanism underlying the cleavage of ether bond remains largely unclear. Here, we attempted to address such concern through identifying the peripheral TPs and analyzing transcriptomics, coupled with serial batch degradation experiments. Analysis results of chromatographic/mass spectrometry suggested that 3-PBA underwent twice hydroxylation , to yield mono- and dihydroxylated 3-PBA successively. In parallel, a mutual transformation between 3-PBA and 3-phenoxybenzyl alcohol (3-PBOH) also existed. The proposal of peripheral pathway represents an important advance towards fully understanding the whole 3-PBA metabolism in M-4. A specific altered metabolization was found for the first time, that is, resting cells of M-4 skipped the reduction step and initiate hydroxylation directly, by comparison with growing cells. Transcriptome analysis indicated that 3-PBA induced the up-regulation of genes related to energy investment, oxidative stress response, membrane transport and DNA repair. In-depth functional interpretation of differential expression genes suggested that the generation 3-PBOH and hydroxylated 3-PBA may be due to the participation of flavin-dependent monooxygenases (FMOs) and cytochrome P450 (CYP450), respectively. This study provides new insight to reveal the biodegradation mechanism of 3-PBA by A . oryzae M-4.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2022
·Vol. 33
·期 29
·23116-23127
·
IF 2.779
Zhang Yu,Xiao Lei,Peng Sen,Li Qiang,Yi Tulin,Liu Weichun,Sun Yuxin
Ba[(Zn 1- x Mg x ) 1/3 Nb 2/3 ]O 3 ( x = 0 ~ 0.9) ceramics were prepared by the traditional solid-phase reaction sintering method. In this paper, the effects of MgO doping on the shrinkage, density, phase composition, crystal structure, microstructure, and microwave dielectric properties of Ba(Zn 1/3 Nb 2/3 )O 3 (BZN) ceramics were investigated. The phase constituents, crystal structure, and microstructure of the ceramics were studied by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscope (SEM), and energy dispersive spectrometer (EDS). The results showed that Ba(Zn 1/3 Nb 2/3 )O 3 as the main phase, and the secondary phase Ba 5 Nb 4 O 15 was detected with high MgO content ( x > 0.3). However, the appearance of secondary Ba 5 Nb 4 O 15 directly led to the deterioration of the microwave dielectric properties of the samples. Ba[(Zn 1– x Mg x ) 1/3 Nb 2/3 ]O 3 ( x = 0.3) ceramics sintered at 1500 °C for 4 h possessed superior dielectric properties: ε r = 36.31, Q × f = 111,326 GHz, τ f = + 12.1 ppm/°C. Such the ceramics could be used to make dielectric resonators and stable oscillators.
✓ 已验证
产品关联
DOI
高影响因子
WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY
·
2022
·Vol. 38
·期 8
·1-11
·
IF 4.253
Xue Kai,Liu Chun-Li,Yang Yankun,Liu Xiuxia,Zhan Jinling,Bai Zhonghu
d -allulose is a rare low-calorie sugar that has many fundamental biological functions. d -allulose 3-epimerase from Agrobacterium tumefaciens (AT-DAEase) catalyzes the conversion of d -fructose to d -allulose. The enzyme has attracted considerable attention because of its mild catalytic properties. However, the bioconversion efficiency and reusability of AT-DAEase limit its industrial application. Magnetic metal–organic frameworks (MOFs) have uniform pore sizes and large surface areas and can facilitate mass transport and enhance the capacity for enzyme immobilization. Here, we successfully encapsulated cobalt-type AT-DAEase into the cobalt-based magnetic MOF ZIF-67@Fe 3 O 4 using a self-assembly strategy. We confirmed the immobilization of enzyme AT-DAEase and characterized the enzymatic properties of the MOF-immobilized AT-DAEase@ZIF-67@Fe 3 O 4 . The AT-DAEase@ZIF-67@Fe 3 O 4 nanoparticles had higher catalytic activity (65.1 U mg −1 ) and bioconversion ratio (38.1%) than the free AT-DAEase. The optimal conditions for maximum enzyme activity of the AT-DAEase@ZIF-67@Fe 3 O 4 nanoparticles were 55 °C and pH 8.0, which were significantly higher than those of the free AT-DAEase (50 °C and pH 7.5). The AT-DAEase@ZIF-67@Fe 3 O 4 nanoparticles displayed significantly improved thermal stability and excellent recycling performance, with 80% retention of enzyme activity at a temperature range of 45–70 °C and > 45% of its initial activity after eight cycles of enzyme use. The AT-DAEase@ZIF-67@Fe 3 O 4 nanoparticles have great potential for large-scale industrial preparation of d -allulose by immobilizing cobalt-type AT-DAEase into magnetic MOF ZIF-67@Fe 3 O 4 .
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2022
·Vol. 169
·期 8
·087517
·
IF 4.386
Shengnan Li,Xinhao Li,Liping Cao,Chaoxian Wang,Jintao Liang,Zhide Zhou,Guiyin Li
Glypican-3 (GPC3) is a serum marker for hepatocellular carcinoma (HCC) and has excellent specificity and sensitivity. Herein, the construction of an electrochemical aptasensor based on reduced graphene oxide-carboxymethyl chitosan-hemin-palladium nanoparticles (RGO-CMCS-Hemin/Pd NPs) and GPC3 aptamer (GPC3apt) has the function of GPC3 identification and analysis. RGO-CMCS-Hemin/Pd NPs has excellent biocompatibility, large specific surface area and good electrical conductivity, which is not only used as advanced sensing materials to modify the electrode surface to reduce the resistance and increase the signal amplitude, but also used as an electroactive substance to provide electrical signals. GPC3apt as a biometric element makes the aptasensor has good specificity and sensitivity. The GPC3apt can combine with GPC3 and form GPC3-aptamer conjugation, which increases the electron transfer impedance and changes the electrical signal. Under the optimum conditions, the aptasensor had a good linear relationship with the GPC3 concentration in the range of 1.0–100.0 ng ml−1 with R2 of 0.9573. The lower limit of detection was 1.0 ng ml−1. When the aptasensor was applied to GPC3 detection in human serum samples, the recovery was 93.73%–118.83%. In addition, the GPC3 aptasensor has excellent specificity, reproducibility and stability, which is anticipated to be applied for the clinical detection of GPC3.
✓ 已验证
产品关联
DOI
高影响因子
Microbiology Spectrum
·
2022
·
IF 9.043
Lujun Yin,Ping-Ping Zhang,Wei Wang,Shi Tang,Shi-Ming Deng,Ai-Qun Jia
Serratia marcescens (S. marcescens) is an environmental bacterium that causes infections with high morbidity and mortality. Notably, infections caused by multidrug-resistant S. marcescens have become a global public health issue. Therefore, the discovery of promising compounds to reduce the virulence of pathogens and restore antibiotic activity against multidrug-resistant bacteria is critical. Quorum sensing (QS) regulates virulence factors and biofilm formation of microorganisms to increase their pathogenicity and is, therefore, an important factor in the formation of multidrug resistance. In this study, we found that 3-phenylpropan-1-amine (3-PPA) inhibited S. marcescens NJ01 biofilm formation and virulence factors, including prodigiosin, protease, lipase, hemolysin, and swimming. The combination of 3-PPA (50.0 μg/mL) and ofloxacin (0.2 μg/mL) enhanced S. marcescens NJ01 sensitivity to ofloxacin. Based on crystalline violet staining, scanning electron microscopy (SEM), and confocal laser scanning microscopy (CLSM), 3-PPA (50.0 μg/mL) reduced S. marcescens NJ01 biofilm formation by 48%. Quantitative real-time PCR (qRT-PCR) showed that 3-PPA regulated the expression of virulence- and biofilm-related genes fimA, fimC, bsmB, pigP, flhC, flhD, and sodB. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) indicated that 3-PPA affected intracellular metabolites of S. marcescens NJ01, leading to reduce metabolic activity. These results suggested that 3-PPA inhibits the pathogenicity of S. marcescens NJ01 by occluding QS. Thus, 3-PPA is feasible as an ofloxacin adjuvant to overcome multidrug-resistant S. marcescens and improve the treatment of intractable infections.IMPORTANCE Multidrug-resistant bacteria have become a major threat to global public health, leading to increased morbidity, mortality, and health care costs. Bacterial virulence factors and biofilms, which are regulated by quorum sensing (QS), are the primary causes of multidrug resistance. In this study, 3-PPA reduced virulence factors and eliminated biofilm formation by inhibiting QS in S. marcescens NJ01 bacteria, without affecting bacterial growth, thus restoring sensitivity to ofloxacin. Thus, the discovery of compounds that can restore antibiotic activity against bacteria is a promising strategy to mitigate multidrug resistance in pathogens.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CRYSTENGCOMM
·
2022
·Vol. 24
·期 17
·3217-3229
·
IF 3.756
Yang Tao,Xiaoting Liu,Yunping Zhoujin,Panpan Zhou,Sean Parkin,Tonglei Li,Ju Guo,Faquan Yu,Sihui Long
To probe the effect of substitution on the benzoic acid ring on the polymorphism of phenylaminobenzoic acids, five 3-methyl-2-(phenylamino)benzoic acids (MPABAs) were synthesized. A preliminary polymorph screen led to one form for compounds 1–4 and three forms and a solvate (5-I, 5-II, 5-III, and 5-S) for compound 5. This observation is similar to that of the structurally related compounds with no substitution on the benzoic acid ring. All crystal forms were characterized by single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), and FT-IR spectroscopy. The polymorphs of compound 5 were investigated in detail experimentally and theoretically. A conformational scan provided insight into the origin of polymorphism of 5. NBO calculations confirmed the composition and nature of the sigma bond character of the two N–C bonds in 5. Hirshfeld analysis accounted for the major intermolecular interactions contributing to the overall stability of the crystals. It is clear that conformational flexibility alone doesn't lead to polymorphism, and substitution position and pattern are the real determinant of polymorphism in the investigated compounds.
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
·
2022
·Vol. 12
·期 3
·304
·
IF 4.501
Xinxing Gao,Qianqian Pei,Nianqing Zhu,Yi Mou,Jilei Liang,Xin Zhang,Shoushuai Feng
(S)-N-Boc-3-hydroxypiperidine is an important intermediate of the anticancer drug ibrutinib and is mainly synthesized by the asymmetric reduction catalyzed by ketoreductase coupled with glucose dehydrogenase at present. In this study, the coexpression recombinant strainsE. coli/pET28-K-rbs-G with single promoter andE. coli/pETDuet-K-G with double promoters were first constructed for the coexpression of ketoreductase and glucose dehydrogenase in the same cell. Then, the catalytic efficiency ofE. coli/pET28-K-rbs-G for synthesizing (S)-N-Boc-3-hydroxypiperidine was found to be higher than that ofE. coli/pETDuet-K-G due to the more balanced activity ratio and higher catalytic activity. On this basis, the catalytic conditions ofE. coli/pET28-K-rbs-G were further optimized, and finally both the conversion of the reaction and the optical purity of the product were higher than 99%. In the end, the cell-free extract was proved to be a better catalyst than the whole cell with the improved catalytic efficiency of different recombinant strains. This study developed a better coexpression strategy for ketoreductase and glucose dehydrogenase by investigating the effect of activity ratios and forms of the biocatalysts on the catalytic efficiency deeply, which provided a research basis for the efficient synthesis of chiral compounds.Keywords:(S)-N-Boc-3-hydroxypiperidine;coexpression strategy;activity ratio;ketoreductase;glucose dehydrogenase
✓ 已验证
产品关联
DOI
高影响因子
Journal of Advanced Dielectrics
·
2022
·
IF 0
Chuan Chen,Yan Wang,Jiajiu Li,Chaofeng Wu,Guanrong Yang
A series of (100 − x ) Pb(Mg 1 / 3 Nb 2 / 3 ) O 3 − x PbTiO 3 (PMN − x PT, x = 24, 25, 26) ceramics were prepared by solid-state reaction technique using MgNb 2 O 6 precursor. The results of the detailed characterizations reveal that the content of PT has negligible influence on the grain size, and all samples possess the perovskite structure. As the PT content increases, the samples changed from the normal ferroelectric phase to the ergodic relaxor state at room temperature. As a result, PMN– x PT ceramics are endowed with electro-strain of 0.08% at a relatively low electric field of 2 kV/mm, and effective piezoelectric coefficient of 320 pm/V was obtained. Simultaneously, the PMN– x PT ceramics have exceptional pyroelectric performance, exhibiting a high pyroelectric coefficient p ∼ 5.5 – 6.3 × 10 − 8 C⋅cm − 2 ⋅K − 1 . This study demonstrates the great potential of PMN– x PT for piezoelectric and pyroelectric device applications.
✓ 已验证
产品关联
DOI
Advanced Energy Materials
·
2022
·Vol. 12
·期 14
·2103666
·
IF 29.698
Yuchen Li,Qikai Li,Xinbo Zhang,Biao Deng,Chenggong Han,Weishu Liu
Ionic thermoelectric (i-TE) cells, using ions as energy carriers, have the advantage of achieving a high voltage of 1−5 V at approximately ambient temperature, showing a promise as a technology for powering Internet-of-Things (IoT) sensors. However, the low output power of i-TE cells restricts their applications. Here, a 3D hierarchical structure electrode is designed to enlarge the electroactive surface area, significantly increasing the thermogalvanic reaction sites and decreasing the interface charge transfer resistance. The quasi-solid-state gelatin-KCl-FeCN 4–/3– i-TE cells achieve a record instantaneous output power density (8.9 mW m –2 K –2 ) and an ultrahigh 2 h output energy density ( E 2h ) (80 J m –2 ) under an optimal temperature range. An average E 2h value of 59.4 J m –2 is obtained over the course of a week of operation. A wearable device consisting of 24 i-TE cells can generate a high voltage of 2.8 V and an instantaneous output power of 68 µW by harvesting body heat. A simple and easy-to-operate electrode optimization strategy is provided here to increase the long-term output power performance of i-TE cells. This work represents a promising approach to develop reliable and green power sources for IoT sensors near room temperature.
✓ 已验证
产品关联
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2021
·
IF 4.098
Huixue Wang,Jinya Liu,Wei Chen,Jintong Na,Yong Huang,Guiyin Li
Glypican-3 (GPC3), a heparin sulfate proteoglycan, is a potential diagnostic and therapeutic target for hepatocellular carcinoma. In this paper, a novel fluorescent aptasensor for GPC3 detection is constructed via [email protected] quantum dots–labeled GPC3 aptamer ( [email protected] Apt ) as a fluorescence probe. First, [email protected] is screened out with higher fluorescence intensity, which emits bright blue fluorescence under ultraviolet light. Then, the fluorescence-labeled [email protected] Apt probe is formed by the combination of amination GPC3 Apt and [email protected] using EDC/NHS coupled reaction. Under hydrogen bond and π-π interaction/stacking, the fluorescence of [email protected] Apt could be quenched by reductive graphene oxide (RGO) with the help of the photoinduced electron transfer and the fluorescence resonance energy transfer mechanism. In the presence of GPC3, the [email protected] Apt specifically recognizes and binds to GPC3, giving rise to the change of secondary structure of GPC3 Apt to form the GPC3/GPC3 Apt [email protected] complex, which would lead to the disintegration of the [email protected] Apt -RGO compound. Therefore, the energy transfer process is blocked and the fluorescence intensity is restored, enabling a highly sensitive response to GPC3. When the concentration of GPC3 is from 5.0 ng/mL to 150.0 ng/mL, the fluorescence recovery rate is well linearly related to GPC3 concentration with the limit of detection of 2.395 ng/mL (S/N = 3). This strategy shows recoveries from 98.31% to 101.89% in human serum samples and provides simple, fast and cheap analysis of GPC3, which suggests that it has great potential applications in clinical diagnosis for hepatocellular carcinoma.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）