APPLIED AND ENVIRONMENTAL MICROBIOLOGY
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2015
·Vol. 81
·期 6
·
IF 3.668
Zhoukun Li,Jiale Wu,Biying Zhang,Fei Wang,Xianfeng Ye,Yan Huang,Qiang Huang,Zhongli Cui
A novel α-amylase, AmyM, was purified from the culture supernatant of Corallococcus sp. strain EGB. AmyM is a maltohexaose-forming exoamylase with an apparent molecular mass of 43 kDa. Based on the results of matrix-assisted laser desorption ionization–time of flight mass spectrometry and peptide mass fingerprinting of AmyM and by comparison to the genome sequence of Corallococcus coralloides DSM 2259, the AmyM gene was identified and cloned into Escherichia coli. amyM encodes a secretory amylase with a predicted signal peptide of 23 amino acid residues, which showed no significant identity with known and functionally verified amylases. amyM was expressed in E. coli BL21(DE3) cells with a hexahistidine tag. The signal peptide efficiently induced the secretion of mature AmyM in E. coli. Recombinant AmyM (rAmyM) was purified by Ni-nitrilotriacetic acid (NTA) affinity chromatography, with a specific activity of up to 14,000 U/mg. rAmyM was optimally active at 50°C in Tris-HCl buffer (50 mM; pH 7.0) and stable at temperatures of <50°C. rAmyM was stable over a wide range of pH values (from pH 5.0 to 10.0) and highly tolerant to high concentrations of salts, detergents, and various organic solvents. Its activity toward starch was independent of calcium ions. The Km and V max of recombinant AmyM for soluble starch were 6.61 mg ml−1 and 44,301.5 μmol min−1 mg−1, respectively. End product analysis showed that maltohexaose accounted for 59.4% of the maltooligosaccharides produced. These characteristics indicate that AmyM has great potential in industrial applications.
研究领域:
生物化学
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酶学
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微生物学
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DOI
PubMed
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
·
2015
·Vol. 81
·期 11
·
IF 3.668
Huajun Feng,Xueqin Zhang,Kun Guo,Eleni Vaiopoulou,Dongsheng Shen,Yuyang Long,Jun Yin,Meizhen Wang
Fed batch bioelectrochemical systems (BESs) based on electrical stimulation were used to treat p-fluoronitrobenzene (p-FNB) wastewater at high salinities. At a NaCl concentration of 40 g/liter, p-FNB was removed 100% in 96 h in the BES, whereas in the biotic control (BC) (absence of current), p-FNB removal was only 10%. By increasing NaCl concentrations from 0 g/liter to 40 g/liter, defluorination efficiency decreased around 40% in the BES, and in the BC it was completely ceased. p-FNB was mineralized by 30% in the BES and hardly in the BC. Microorganisms were able to store 3.8 and 0.7 times more K+ and Na+ intracellularly in the BES than in the BC. Following the same trend, the ratio of protein to soluble polysaccharide increased from 3.1 to 7.8 as the NaCl increased from 0 to 40 g/liter. Both trends raise speculation that an electrical stimulation drives microbial preference toward K+ and protein accumulation to tolerate salinity. These findings are in accordance with an enrichment of halophilic organisms in the BES. Halobacterium dominated in the BES by 56.8% at a NaCl concentration of 40 g/liter, while its abundance was found as low as 17.5% in the BC. These findings propose a new method of electrical stimulation to improve microbial salinity resistance.
研究领域:
环境科学
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微生物学
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生物技术
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DOI
PubMed
高影响因子
JOURNAL OF AOAC INTERNATIONAL
·
2019
·Vol. 98
·期 1
·225-229
·
IF 1.201
Zhang Jing,Yong Xiaojing,Zhao Dongyan,Shi Qiuyi
The content of mononuclear Al (Ala%) changed with its determination time (ta) under different dosages of Ferron (7-iodo-8-hydroxyquinoline-5-sulfonic acid, [Ferron]), and the change of Ala% with [Ferron] at different ta was systematically investigated for the firsttime. Thus, the most appropriate ta was found with the optimal [Ferron]. Also, the judgment of the platform (flat or level portion) of the complete reaction on the absorption-time curve determined in the hydroxyl polyaluminum solution by Ferron timed spectrophotometry (Ferron assay) was first digitized. The time point (tb) of complete reaction between the medium polyaluminum (Alb)and Ferron reagent depended on the reaction extent, and time could not be used only to judge. Thus, the tb was accurately determined and reduced
to half of original, which improved the experiment efficiency significantly. The Ferron assay was completely optimized.
研究领域:
分析化学
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环境科学
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DOI
PubMed
高影响因子
JOURNAL OF AOAC INTERNATIONAL
·
2019
·Vol. 98
·期 2
·422-430
·
IF 1.201
Zong Yingying,Lin Jia,Xu Hua,Jia Zhihui,Yang Xiupei,Choi Martin M F
A novel isocratic RP–HPLC method with UV photodiode array detection for the determination of seven organic acids in vinegar samples was developed and optimized. Samples were analyzed on a C18 (150 × 4.6 mm id, 5 μm) analytical column. Methanol–0.010 M sodium dihydrogen phosphate buffer adjusted with H3PO4 to pH 2.80 (2 + 98, v/v), was used as the mobile phase. The column oven temperature was optimized at 23.0°C, the flow rate was 0.80 mL/min, and the detection wavelength was 210 nm. Matrix-matched calibration curves were prepared for all analytes, and the correlation coefficients were greater than 0.99. LOD and LOQ ranged from 0.10 to 10.0 and 0.30 to 30.0 μg/mL, respectively. The results for interday and intraday precision and accuracy fell within the ranges specified. Vinegar samples were quantified by the standard addition method. The main advantages of this method are its selectivity, which is one of themain weaknesses of most methods when determining organic acids in complex matrixes, and its simplicity since little sample preparation is needed. Moreover,it is safe and inexpensive with low organic solvent usage.
研究领域:
食品科学
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分析化学
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DOI
PubMed
高影响因子
Translational Andrology and Urology
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2023
·
IF 2
Tianqin Deng,Xuemei Li,Bing Yao
Background In the pathological study of necrozoospermia—a form of sperm mortality—the underlying metabolic mechanism remains unclear. Thus, the aim of this study was to characterize metabolic alterations in the seminal plasma of necrozoospermic patients and to provide insights into the etiology of the disease. Methods Seminal plasma samples were collected from patients diagnosed with necrozoospermia (n=28) as well as normozoospermia (n=37). The samples were analyzed using nontargeted metabolomics based on liquid chromatography-mass spectrometry (LC-MS). The raw data were subjected to multivariate analysis to identify metabolites correlated with necrozoospermia. Differential metabolites were subjected to pathway analysis using MetaboAnalyst. Results The results of the metabolomic analysis showed that there were 194 differential metabolites between the two groups; 129 metabolites were upregulated and 65 metabolites were downregulated. Among the differential metabolites, the top ten differential metabolites were choline, benzaldehyde, pyrazinamide, 5-aminoimidazole-4-carboxamide, and dihydrothymine. The following differential metabolite pathways were identified, and the top five metabolite pathways were arachidonic acid metabolism, steroid hormone biosynthesis, alanine aspartate and glutamate metabolism, bile secretion, and prostate cancer. Conclusions The elevation of choline and 2-hydroxyglutarate levels in seminal plasma was an important finding, and the results also indicate that abnormalities in arachidonic acid metabolism and glutamate metabolism were an underlying pathological mechanism of necrozoospermia.
研究领域:
生殖医学
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代谢组学
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DOI
PubMed
高影响因子
JOURNAL OF MEDICINAL CHEMISTRY
·
2023
·
IF 7.3
Zhiyuan Cheng,Yijie Wang,Yao Zhang,Chan Zhang,Mengru Wang,Wei Wang,Jiacheng He,Yang Wang,Hankun Zhang,Qiansen Zhang,Chunyong Ding,Deyan Wu,Linlin Yang,Mingyao Liu,Weiqiang Lu
Nowadays, small-molecule drugs have become an indispensable part of tumor immunotherapy. Accumulating evidence has indicated that specifically blocking PGE2/EP4 signaling to induce robust antitumor immune response represents an attractive immunotherapy strategy. Herein, a 2H-indazole-3-carboxamide containing compound 1 was identified as a EP4 antagonist hit by screening our in-house small-molecule library. Systematic structure–activity relationship exploration leads to the discovery of compound 14, which displayed single-nanomolar EP4 antagonistic activity in a panel of cell functional assays, high subtype selectivity, and favorable drug-like profiles. Moreover, compound 14 profoundly inhibited the up-regulation of multiple immunosuppression-related genes in macrophages. Oral administration of compound 14, either as monotherapy or in combination with an anti-PD-1 antibody, significantly impaired tumor growth via enhancing cytotoxic CD8+ T cell-mediated antitumor immunity in a syngeneic colon cancer model. Thus, these results demonstrate the potential of compound 14 as a candidate for developing novel EP4 antagonists for tumor immunotherapy.
研究领域:
肿瘤学
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免疫学
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药理学
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DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 114
·94091-94098
·
IF 3.84
Fei Liu,Junwu Zhang,Jinggang Wang,Haining Na,Jin Zhu
Thermal and tensile properties of thermoplastic elastomers (e.g. poly(butylene terephthalate)-b-poly(tetramethylene glycol) (PBT–PTMG)) are usually tuned by changing the composition of hard and soft segment parts. Simply increasing the amount of soft segment results in a lower melting temperature and better elastic properties, but the thermal stability and tensile properties are inevitably sacrificed. In this work, by incorporation of an aliphatic ring structure (i.e. 1,4-cyclohexanedicarboxylic acid) (CHDA) to partially replace the aromatic ring (i.e. terephthalic acid) in PBT-PTMG, the properties of the material can be tuned in such a way that the melting temperature decreases, while the thermal stability, tensile and elastic properties are not compromised. Moreover, manipulation of the stereo-chemistry of the CHDA unit discloses the “elastic” nature of the non-planar ring structure. Samples with a greater amount of cis-CHDA tend to have better tensile and elastic properties compared with their trans-CHDA counterparts.
研究领域:
材料科学
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聚合物化学
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DOI
高影响因子
Metabolites
·
2023
·Vol. 13
·期 1
·90
·
IF 4.1
Zhihong Yue,Lin Pei,Guangyan Meng,Aimin Zhang,Meng Li,Mei Jia,Hui Wang,Linlin Cao
Type 2 diabetes mellitus (T2DM) has been recognized as one of the most important and independent risk factors for hepatocellular cancer (HCC). However, there is still a lack of ideal tumor markers for HCC detection in the T2DM population. Serum lipids have been revealed as potential tumor markers for HCC. In this study, our objective was to develop a novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to detect several lipids including 8,15-dihydroxy-5,9,11,13-eicosatetraenoic acid (8,15-DiHETE), hexadecanedioic acid (HDA), 15-keto-13,14-dihydroprostaglandin A2 (DHK-PGA2), ricinoleic acid (RCL), octadecanedioic acid (OA) and 16-hydroxy hexadecanoic acid (16OHHA) in serum and explore their diagnostic potential for T2DM-positive [T2DM(+)] HCC. A robust LC-MS/MS method was established for the measurement of 8,15-DiHETE, HDA, DHK-PGA2, RCL, OA, and 16OHHA. The methodology validation was conducted, and the results suggested the reliability of this LC-MS/MS method for targeted lipids. Several serum lipids, including 8,15-DiHETE, HDA, DHK-PGA2, and OA were increased in T2DM(+) HCC patients. A biomarker signature that incorporated HDA, DHK-PGA2, and AFP was established and showed good diagnostic potential for T2DM(+) HCC, and the area under the ROC curve (AUC) was 0.87 for diagnosing T2DM(+) HCC from T2DM individuals. Additionally, the biomarker signature diagnosed small-size (AUC = 0.88) and early-stage (AUC = 0.79) tumors with high efficacy. Moreover, the biomarker signature could differentiate T2DM(+) HCC from other T2DM(+) tumors, including pancreatic, gastric and colorectal cancer (AUC = 0.88) as well. Inconclusion,our study develops a novel tool for early diagnosis of T2DM(+) HCC in T2DM patients.Keywords:hepatocellular cancer;serum lipids;type 2 diabetes mellitus;hexadecanedioic acid;15-keto-13,14-dihydroprostaglandin A2;biomarker signature
研究领域:
医学
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肿瘤学
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代谢组学
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DOI
PubMed
高影响因子
INORGANIC CHEMISTRY
·
2020
·
IF 4.825
Wan Jiang,Yuyuan Bai,Qinzhen Li,Xiean Yao,Hui Zhang,Yongbo Song,Xiangming Meng,Haizhu Yu,Manzhou Zhu
An understanding of the response of nanomaterials to specific environmental parameters is an essential prerequisite for their practical use, especially in living systems. Herein, we disclose the preparation of a water-soluble nanocluster Au16(SR)12 (SR denotes deprotonated captopril) and its characterization by a combination of theoretical (e.g., density functional theory calculations) and experimental (UV–vis, electrospray ionization mass spectrometry, etc.) methods. Interestingly, Au16(SR)12 was found to convert to Au18(SR)14 under acidic conditions, while the reverse conversion from Au18(SR)14 to Au16(SR)12 occurred upon the addition of base. A mechanistic investigation determined this pH regulation to originate from the distinct steric and electrostatic properties of these two clusters. This study is the first to report the susceptibility of Au18(SR)14 and Au16(SR)12 to pH, and the distinct pH stability unambiguously reveals the importance of size-tracking of nanomaterials in living systems for future clinical applications.
研究领域:
纳米材料
·
生物化学
·
理论计算
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DOI
PubMed
高影响因子
CARBOHYDRATE RESEARCH
·
2025
·
IF 2.5
Wei Wang,Jiarong Zhu,Yizhou Wang,Liangkun Long,Qunying Lin,Jing Wang,Shaojun Ding
Two new ɑ -galactosidases PpAgl27B and PpAgl27C from Penicillium parvum 4–14 were functionally investigated in this study. Based on the analysis of catalytic domain and phylogenetic tree, PpAgl27B (435 aa) and PpAgl27C (543 aa) belong to glycoside hydrolase (GH) 27 family. After expression in Pichia pastoris , the recombinant PpAgl27B and PpAgl27C showed the highest activities at pH 3.5 and 65 °C, or 4.0 and 45 °C, respectively. Using p -nitrophenyl- α - d -galactopyranoside ( p NPGal) as substrate, the Michaelis constant were 0.90 mM for PpAgl27B and 2.54 mM for PpAgl27C. PpAgl27C had a low catalytic activity toward p NPGal and negligible activities on various natural substrates. Differently, PpAgl27B efficiently released galactose from the artificial substrate, raffinose family oligosaccharides, or galactomannans. Hydrolysis of corn bran arabinoxylan (CBAX) 1 or 2 were conducted by PpAgl27B alone or in combination with the enzyme blend E_CBAX1. PpAgl27B released a small amount of galactose (1.7–3.0 mg/g) from the both substrates. Compared with the individual enzymes, the liberations of galactose, xylose and arabinose from the substrates were significantly enhanced by combing PpAgl27B and E_CBAX1. The degrees of synergy of the enzyme combination for the saccharification of CBAX1 or CBAX2 were 1.20 and 1.13, respectively. PpAgl27B showed promising potential for the valorization of galactose-rich feedstocks as well as CBAX.
研究领域:
生物化学
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酶工程
·
微生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2022
·
IF 3.119
Yang Li,Kejia Liu,Long Meng,Yong Wang
The solubility of methyl 1,2,4-triazole-3-carboxylate in 14 solvents (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, isobutyl alcohol, acetonitrile, acetone, 2-pentanone, 3-pentanone, 4-methyl-2-pentanone, cyclopentanone, cyclohexanone, tetrahydrofuran) in the range from 278.15 to 318.15 K and at atmospheric pressure was measured in this study. The solubility of methyl 1,2,4-triazole-3-carboxylate in all solvents increases with the increasing temperature. The solubility of methyl 1,2,4-triazole-3-carboxylate in the solvents except for methanol and cyclohexanone does not show much difference, and is significantly smaller than that in methanol and cyclohexanone. The solubility of methyl 1,2,4-triazole-3-carboxylate is not strictly related to polarity of the solvents as it is to the existence of other factors. The solubility of methyl 1,2,4-triazole-3-carboxylate was correlated by the λh equation, modified Apelblat model, and Yaws model. The Yaws model is the best one among the three models with average relative deviation (ARD) and average root-mean-square deviation (104(RMSD)) of 1.18% and 0.364. The work in this study provides important solubility data for purification and synthesis of methyl 1,2,4-triazole-3-carboxylate.
研究领域:
化学工程
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物理化学
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DOI
高影响因子
Food Analytical Methods
·
2023
·Vol. 16
·期 3
·633-649
·
IF 2.9
Li Fan,Wang Zhanhua,Zhu Bingqi,Xu Xiaoying,Liu Zhu
Anesthetics are widely applied in cultivation and transportation of aquatic products to reduce the metabolism of fish and avoid some stress reactions. The overdose of using anesthetics or the occurrence of their residues in the aquatic products may negatively affect human health after consumption. A rapid screening procedure and a new analytical method for the simultaneous determination of 14 anesthetics was established in this study. The compounds were extracted from fish and shrimp matrices by sodium acetate buffer solution, cleaned up via solid-phase extraction, and then were analyzed using an ultrahigh-performance liquid chromatography system coupled with a tandem quadrupole-time-of-flight mass spectrometer (UPLC-Q-TOF–MS) in a positive-ion mode. Methodological verification analyses, including linearity, precision, recovery, limit of detection (LOD), and limit of quantification (LOQ), were conducted to validate the method. The correlation coefficient of the calibration curves of each anesthetic exceeded 0.99. The average recoveries of this analysis method varied from 72.36 to 111.27% with relative standard deviations less than 5%. The detection limit of anesthetics reached 0.3–0.7 μg/kg. Agilent Mass Hunter Personal Compound Database Library (PCDL) Manager was used to establish a database of 14 anesthetics and 8 isotope internal standards, which enabled a quick screening and analysis without standard substances. The results of the spiked blank samples demonstrated reliability of the screening method with mass deviations less than 5 ppm and the scores determined by relative molecular mass, retention time, isotope ratio, and distribution all greater than 85. In addition, according to the fragmentation information of mass spectrometry, the fragmentation rules of some anesthetics were summarized. This method was validated with reliable results in quantitative and qualitative analysis and could be used as regulatory measures for anesthetics in aquatic products.
研究领域:
食品安全
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分析化学
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环境科学
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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）