APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
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2018
·Vol. 103
·期 2
·793-806
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IF 3.34
Yang Haiquan,Hu Jinyuan,Lu Xiao,Wang Fuxiang,Shen Wei,Hu Wei,Wang Lingling,Chen Xianzhong,Liu Long
Most recombinant proteins in Escherichia coli are not efficiently secreted to the extracellular space. Structural stabilisation of the cell wall is essential for extracellular protein production in E. coli , for which D,D-carboxypeptidases are essential. Herein, we perturbed the peptidoglycan structure of the E. coli cell wall by overexpressing D,D-carboxypeptidase genes dacA or dacB , and investigated the effect on extracellular protein production. Overexpression of dacA or dacB promoted the accumulation of intracellular soluble peptidoglycan, altered cell morphology (shape and size) and led to the formation of transparent globular structures in E. coli cells. Compared with controls (CK), extracellular production of recombinant green fluorescent protein (GFP) was increased by 1.7- and 2.3-fold upon overexpression of dacA and dacB , respectively. Similarly, extracellular production of recombinant amylase and α-galactosidase was increased by 4.5- and 2.8-fold, respectively, upon overexpression of dacA , and by 11.9- and 2.5-fold, respectively, upon overexpression of dacB . Overexpression of dacA or dacB enhanced both the outer and inner membrane permeability of E. coli . This cell wall engineering strategy opens up a new direction for enhancing extracellular protein and chemical production in E. coli .
研究领域:
微生物学
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生物技术
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分子生物学
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DOI
PubMed
高影响因子
ACS Applied Electronic Materials
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2022
·
IF 4.494
Zhang Chen,Xiaotian Sun,Zizheng Wang,Yong Zhu,Chuanxiang Cao,Jiadong Zhou,Yanfeng Gao
Porous carbon was fabricated for broadband microwave absorption application, which was obtained from facile KOH activated carbon microspheres prepared from hydrothermal d-fructose. It is found that micropores (diameter < 2 nm) in the porous carbon played an important role in broadband and high microwave absorption properties. The prepared samples can achieve a wide bandwidth (the widest is 7.9 GHz, from 10.1 to 18 GHz), high dielectric loss (−60.0 dB as the best), and low thickness sensitivity (the bandwidth maintains 70% of the maximum within a film thickness fluctuation of up to 1.02 mm). Our findings offered an invaluable insight into designing and synthesizing highly microwave-absorbing materials through the micro/nanostructure.
研究领域:
材料科学
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电磁学
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DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
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2025
·
IF 19
Xinyu Wang,Sichen Huo,Yanjie Chen,Mingyi Wang,Ying Dai,Jinlong Zou
Cobalt atom cluster (Co AC )-based electrocatalysts usually exhibit high activity for oxygen reduction reaction (ORR), but display limited performance in oxygen evolution reaction (OER). To enhance their bifunctional catalytic efficiency, it is crucial to tailor the d -orbital electronic structure of Co AC through orbital coupling effect, optimizing the chemisorption of O-intermediates. Herein, a 3 d -4 d orbital coupling strategy is used to construct a Co AC -molybdenum carbide/nanocarbon cake (Co AC -Mo x C/CC) catalyst with a hollow structure for ORR/OER in zinc-air batteries (ZABs). Experimental and theoretical results confirm that the 4 d transition metal Mo, with fewer d electrons and more unfilled orbitals, interacts strongly with Co sites through d - d coupling, promoting electron enrichment and triggering 3 d -orbital electron delocalization. This process accelerates the rate-limiting steps of *OH desorption for ORR and *OOH formation for OER, leading to an ultra-low potential gap of 0.604 V and improved stability. Notably, the Co AC -Mo x C/CC-based liquid and flexible all-solid-state ZABs exhibit excellent performance with high open-circuit voltages of 1.49 and 1.47 V, and power densities of 146.4 and 103.4 mW cm −2 , respectively, highlighting their potential to replace precious metal catalysts. This study may open new avenues for manipulating the electronic properties of Co AC -based electrocatalysts and boosting activity through the d - d orbital coupling strategy.
研究领域:
材料科学
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电化学
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催化科学
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DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2025
·
IF 6.2
Caiyun Li,Dingwei Zheng,Tianle Zhang,Siyuan Qian,Xinyao Liu,Zhengfu Yang,Kean-Jin Lim,Weihong Min,Jianqin Huang,Yiyi Yang,Zhengjia Wang
Cognitive decline associated with aging and neuroinflammation has been linked to gut microbiota dysbiosis and systemic inflammation, potentially mediated through the gut–brain axis. Bioactive peptides have shown potential as therapeutic candidates for neurodegenerative and neuroinflammatory disorders. While the walnut-derived peptide EVSGPGYSPN (EV-10) has demonstrated cognitive benefits, the therapeutic potential of its recombinant form, recombinant walnut-derived peptide (rWDP), expressed and purified from an Escherichia coli system, remains to be fully characterized. In this study, behavioral assessment using the Morris water maze revealed that rWDP significantly improved spatial learning and memory in d-galactose-induced aging mice. rWDP treatment was associated with changes in gut microbiota composition, including an increase in Akkermansia muciniphila and improvements in colon mucosal integrity. Systemic inflammation appeared to be attenuated, with reduced levels of IFN-γ and VCAM-1 and normalization of G-CSF and CXCL1 levels. In the brain, rWDP was associated with reduced microglial activation and preservation of hippocampal neuronal architecture. Notably, decreased p21 expression was observed in the hippocampus and cortex. In vitro, rWDP suppressed LPS-induced nitric oxide production and attenuated the expression of proinflammatory genes in BV2 microglial cells. Metabolomic analysis suggested a restoration of neurotransmitter homeostasis following rWDP treatment, with increased levels of 5-hydroxyindoleacetic acid, kynurenine, and glutathione observed. Overall, rWDP may alleviate cognitive deficits through multifaceted pathways involving the gut–brain axis and immune modulation, warranting further mechanistic investigation.
研究领域:
神经科学
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生物化学
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微生物学
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免疫学
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药理学
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衰老研究
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代谢组学
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产品关联
DOI
PubMed
高影响因子
ANALYTICAL LETTERS
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2024
·
IF 1.6
Jin-Wen Liu,Tingting Chen,Meiqun Cai,Yingfeng Qin,Mei Li
Accurate, rapid, and quantitative detection of D-penicillamine (D-PA) in pharmaceutical formulations is imperative for drug quality and clinical medication guidance. Various colorimetric and fluorescent assays have been constructed for D-PA based on nanomaterials. However, the reliable and rapid detection of D-PA in pharmaceutical formulations remains a challenge because these methods suffer from shortcomings such as time-consuming procedures, poor uniformity, and complicated nanomaterial preparation. In this work, an effective and facile homogeneous dual-mode optical sensing strategy was established based on the strong complexation between D-PA and Cu2+ and catalyzed the oxidation of O-phenylenediamine. This platform displayed a sensitive response to D-PA from 5 to 100 µmol/L, with a detection limits of 0.54 µmol/L (fluorescence) and 0.76 µmol/L (colorimetry). As expected, the method was successfully applied to the determination of D-PA in pharmaceutical formulations with satisfactory results. Overall, this developed strategy provides a facile and rapid dual-mode optical platform for D-PA and has great potential in D-PA-related pharmaceutical quality control.
研究领域:
分析化学
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药学
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DOI
高影响因子
Nature Communications
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2025
·Vol. 16
·期 1
·1-9
·
IF 15.7
Zhang Xiu-Feng,Zhang Shi-Nan,Zhang Zhao,Leng Bing-Liang,Lu Kai-Yuan,Chen Jie-Sheng,Li Xin-Hao
Deuterated organic compounds have gained significant attention due to their diverse applications, including reaction mechanism studies, probes for metabolism and pharmacokinetics, and raw materials for labeled compounds and polymers. Conventional reductive deuteration methods are limited by the high cost of deuterium sources (e.g., D₂ gas) and challenges in product separation and D₂O recycling. Electrochemical deuteration using D₂O is promising, but existing methods still suffer from low Faradaic efficiency (FE) and high separation costs. Herein, we report a deuterium ion diffusion-based all-solid electrolyser, featuring a RuO₂ anode for D + generation from pure D 2 O and a Pd/nitrogen-doped carbon-based liquid diffusion cathode (Pd δ+ /NC LDC) with tunable electron deficiencies Pd δ+ /NC to enhance selective deuteration. This system achieves over 99% selectivity for deuterated benzyl alcohol with a FE of 72%, and demonstrates broad applicability for the deuteration of aldehydes, ketones, imines, and alkenes with high FE and selectivity. Moreover, the Pd δ+ /NC-based electrolyser can achieve ten-gram-scale production of deuterated benzyl alcohol over 500 hours, showcasing its potential for high-throughput, solvent-free deuteration reactions in practical applications.
研究领域:
有机化学
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药物化学
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合成化学
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DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2024
·
IF 8
Qianxi Zhou,Hao Zhang,Tianyu Zeng,Jiahua Yang,Qizhi Liang,Hai Shi,Yongmei Yin,Genxi Li
The dynamic variation of D-amino acids (D-AAs) in human saliva has great potential as the indicator for individual physiological states and disease progression; however, enantiospecific profiling of D-AAs is a great challenge. In this work, a nanoreactor based on mesoporous hydrogen-bonded organic framework (MHOF) has been fabricated for the enantiospecific profiling of D-AAs. The nanoreactor is prepared by using MHOFs as the scaffold to organize the biocatalytic cascade of D-AA oxidase (DAAO) and horseradish peroxidase (HRP). In the meanwhile, the large, stable, and robust transport channels of MHOFs allow the unimpeded transport of the involved biocatalytic substrates. Once D-AA substrates efficiently transport into MHOFs, the chromogenic reactions of 3,3′,5,5′-tetramethylbenzidine (TMB) and H 2 O 2 can be activated. So, using this MHOF nanoreactor, enantiospecific and visual detection of D-AAs can be achieved. Moreover, the stable nanoreactor can be operated in complex solution and utilized for the profiling of D-AA levels in saliva samples collected from gastric cancer patients, suggesting that D-AAs may be a powerful fingerprint for the diagnosis of gastric cancer. Therefore, the fabricated MHOF-based nanoreactor may provide an emerging tool for the enantiospecific profiling of D-AAs and supports the D-AA fingerprint as the indicator of gastric cancer diagnosis.
研究领域:
医学
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生物化学
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材料科学
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DOI
高影响因子
BMC MICROBIOLOGY
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2024
·Vol. 24
·期 1
·1-12
·
IF 4
Liu Xiaoju,Xiong Yanpeng,Peng Renhai,Zhang Yufang,Cai Shuyu,Deng Qiwen,Yu Zhijian,Wen Zewen,Chen Zhong,Hou Tieying
Multi-drug-resistant Staphylococcus aureus infections necessitate novel antibiotic development. D-3263, a transient receptor potential melastatin member 8 (TRPM8) agonist, has potential antineoplastic properties. Here, we reported the antibacterial and antibiofilm activities of D-3263. Minimum inhibitory concentrations (MICs) against S. aureus , Enterococcus faecalis and E. faecium were ≤ 50 µM. D-3263 exhibited bactericidal effects against clinical methicillin-resistant S. aureus (MRSA) and E. faecalis strains at 4× MIC. Subinhibitory D-3263 concentrations effectively inhibited S. aureus and E. faecalis biofilms, with higher concentrations also clearing mature biofilms. Proteomic analysis revealed differential expression of 29 proteins under 1/2 × MIC D-3263, influencing amino acid biosynthesis and carbohydrate metabolism. Additionally, D-3263 enhanced membrane permeability of S. aureus and E. faecalis . Bacterial membrane phospholipids phosphatidylethanolamine (PE), phosphatidylglycerol (PG), and cardiolipin (CL) dose-dependently increased D-3263 MICs. Overall, our data suggested that D-3263 exhibited potent antibacterial and antibiofilm activities against S. aureus by targeting the cell membrane.
研究领域:
微生物学
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药理学
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感染病学
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产品关联
DOI
PubMed
高影响因子
Food & Function
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2022
·Vol. 13
·期 14
·7507-7519
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IF 6.317
Meng Ru,Wanwan Wang,Zhenya Zhai,Ruxia Wang,Yumeng Li,Jiang Liang,Damini Kothari,Kaimin Niu,Xin Wu
The nicotinamide adenine dinucleotide (NAD+) level shows a temporal decrease during the aging process, which has been deemed as an aging hallmark. Nicotinamide mononucleotide (NMN), a key NAD+ precursor, shows the potential to retard the age-associated functional decline in organs. In the current study, to explore whether NMN has an impact on the intestine during the aging process, the effects of NMN supplementation on the intestinal morphology, microbiota, and NAD+ content, as well as its anti-inflammatory, anti-oxidative and barrier functions were investigated in aging mice and D-galactose (D-gal) induced senescent IPEC-J2 cells. The results showed that 4 months of NMN administration had little impact on the colonic microbiota and NAD+ content in aging mice, while it significantly increased the jejunal NAD+ content and improved the jejunal structure including increasing the villus length and shortening the crypt. Moreover, NMN supplementation significantly up-regulated the mRNA expression of SIRT3, SIRT6, nuclear factor E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), the catalytic subunit of glutamate-cysteine ligase (GCLC), superoxide dismutase 2 (SOD2), occludin, and claudin-1, but down-regulated the mRNA expression of tumor necrosis factor alpha (TNF-α). Specifically, in the D-gal induced senescent IPEC-J2 cells, 500 μM NMN restored the increased mRNA expression of interleukin 6 (IL6ST), IL-1A, nuclear factor (NF-κB1), and claudin-1 to normal levels to some extent. Furthermore, NMN treatment significantly affected the mRNA expression of antioxidant enzymes including NQO1, GCLC, SOD 2 and 3, and GSH-PX1, 3 and 4. In addition, 200 μM NMN enhanced the cell viability and total antioxidant capacity and lowered the reactive oxygen species level of senescent IPEC-J2 cells. Notably, NMN restored the down-regulated protein expression of occludin and claudin-1 induced by D-gal. The above data demonstrated the potential of NMN in ameliorating the structural and functional decline in the intestine during aging.
研究领域:
老年学
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分子生物学
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药理学
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细胞生物学
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产品关联
DOI
PubMed
高影响因子
Foods
·
2022
·Vol. 11
·期 20
·3225
·
IF 5.561
Xinrui Tang,Yingfeng An,Muhammad Waheed Iqbal,Hongri Cong,Guoyan Zhang,Yufei Zhang,Yuvaraj Ravikumar,Hossain M. Zabed,Mei Zhao,Haixing Zhou,Xianghui Qi
D-allulose is a natural rare sugar with important physiological properties that is used in food, health care items, and even the pharmaceutical industry. In the current study, a novel D-allulose 3-epimerase gene (Bp-DAE) from the probiotic strainBlautia producawas discovered for the production and characterization of an enzyme known as Bp-DAE that can epimerize D-fructose into D-allulose. Bp-DAE was strictly dependent on metals (Mn2+and Co2+), and the addition of 1 mM of Mn2+could enhance the half-life of Bp-DAE at 55 °C from 60 to 180 min. It exhibited optimal activity in a pH of 8 and 55 °C, and theKmvalues of Bp-DAE for the different substrates D-fructose and D-allulose were 235.7 and 150.7 mM, respectively. Bp-DAE was used for the transformation from 500 g/L D-fructose to 150 g/L D-allulose and exhibited a 30% of conversion yield during biotransformation. Furthermore, it was possible to employ the food-grade microbial speciesBacillus subtilisfor the production of D-allulose using a technique of whole-cell catalysis to circumvent the laborious process of enzyme purification and to obtain a more stable biocatalyst. This method also yields a 30% conversion yield.Keywords:D-allulose 3-epimerase;D-allulose;Blautia produca;probiotics;biochemical characterization;biotransformation
研究领域:
生物化学
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生物技术
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食品科学
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药学
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DOI
PubMed
高影响因子
ENGINEERING IN LIFE SCIENCES
·
2019
·Vol. 19
·期 4
·270-278
·
IF 1.936
Jinyuan Hu,Xiao Lu,Haokun Wang,Fuxiang Wang,Yuan Zhao,Wei Shen,Haiquan Yang,Xianzhong Chen
d -Alanyl- d -alanine carboxypeptidase DacC is important for synthesis and stabilization of the peptidoglycan layer of Escherichia coli . In this work, dacC of E . coli BL21 (DE3) was successfully deleted, and the effects of this deletion on extracellular protein production in E . coli were investigated. The extracellular activities and fluorescence value of recombinant amylase, green fluorescent protein, and α-galactosidase of the deletion mutants were increased by 82.3, 29.1, and 37.7%, respectively, compared with that of control cells. The outer membrane permeability and intracellular soluble peptidoglycan accumulation of deletion mutant were also enhanced compared with those of control cells, respectively. Based on fluorescence-assisted cell sorting analyses, we found that the morphology of the E. coli deletion mutant cells was altered compared with that of control cells. Local transparent bulges in the poles of the E . coli mutant with deletion of the dacC gene were found by transmission electron microscopy analysis. These bulges in the poles could explain the improvement in the production of extracellular protein by the E. coli mutant with deletion of the dacC gene. These findings provide important insights into the extracellular production of proteins using E . coli as microbial cell factories.
研究领域:
微生物学
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生物技术
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分子生物学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2013
·
IF 1.684
Wenbiao Zhi,Yonghong Hu,Wenge Yang,Yumei Kai,Zheng Cao
The solubility of d -sorbitol was measured in methanol, ethanol, n-propanol, n-butanol, THF, acetone, ethyl acetate and acetonitrile at temperatures ranging from 278.15 to 333.15 K under atmospheric pressure by gravimetric method. The solubility data were correlated with modified Apelblat equation and λh equation which showed that the solubility of d -sorbitol in these organic solvents increased with increasing temperature. The thermodynamic properties of the dissolution process, including enthalpy, entropy and Gibbs energy , were calculated by means of van't Hoff analysis and Gibbs equation. According to the experimental results, ethanol showed to be a relatively better solvent in crystallization process of d -sorbitol.
研究领域:
物理化学
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化工
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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）