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Purification and Characterization of a New Heme-Binding （HBP59） from the Mutant Strain DJ35 of Azotobacter vinelandii

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Journal of Integrative Plant Biology 2007年第3期49卷 336-342页

作者： Shao-Min Bian huang-ping wang Hui-Na Zhou Ying Zhao Jian-Feng Zhao Ju-Fu huang Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Bioengineering College Fujian Normal University Fuzhou 350007 China Graduate School the Chinese Academy of Sciences Beijing 100039 China

A new protein, an approximately 59-kDa monomer containing iron atoms, was first isolated from the mutant strain DJ35 of Azotobacter vinelandii Llpmann. After analysis by matrix-assisted laser desorptlon ionization time-of-flight mass spectrometry, the protein was Identified as the product of a predicted gene. Thus, the protein was tentatively called HBP59. Its absorption spectra （ABS） In the reduced state exhibited three peaks at 421,517, and 556 nm and the maximal peak was shifted from 421 to 413 nm after exposure of HBP59 to air. The Soret circular dichrolsm （CD） spectrum of HBP59 In the reduced state displayed four positive peaks at 364, 382, 406, and 418 nm and two negative peaks at 398 and 433 nm; the △ε （CD extinction coefficient） values of these peaks were found to be 0.92, 0.58, 0.87, 0.72, -0.65 and -1.12 L/mol per cm, respectively. Titration with heme showed that the protein has 0.1 heme molecules/protein molecule. After HBP59 had fully Interacted with heme, Its maximal ABS value and Soret CD Intensity were increased by approximately 10-fold compared with values before Interaction. Therefore, It seems that one molecule of HBP59 can be interacted with only one heme. These results indicate that HBP59 contains heme with low spin and may be Involved In heme utilization or adhesion.

关键词： absorption spectra Azotobacter vinelandii characterization by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) circular dichroism spectra and titration heme-binding protein (HBP59) mutant strain DJ35 purification

Identification of Contaminations Hiding Beneath the α- and β-Subunits of Partially Purified Nitrogenase MoFe Protein on the Sodium Dodecyl Sulfate Gel

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Journal of Integrative Plant Biology 2005年第11期47卷 1364-1371页

作者： Hui-Na ZHOU Ying ZHAO Shao-Min BIAN Jian-Feng ZHAO Fei REN huang-ping wang Ju-Fu huang Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China China Agricultural University Beijing 100094 China Fujian Normal University Fuzhou 350007 China

To identify the unknown proteins that would contaminate the α- and β-subunits of nitrogenase MoFe protein on sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE）, the partially purified MoFe protein （Avl） preparation was obtained from Azotobacter vinelandii Lipmann OP by chroma- tography on DEAE-cellulose （DE52） and Sephacryl S-200 columns and analyzed by PAGE and matrix- assisted laser desorption/ionization time-of-flight （MALDI-TOF） mass spectrometry. The Av 1 preparation was shown to have two main bands at the position of the α- and β-subunits of crystalline Avl on the SDS gel. However, on the anoxic native PAGE, in addition to the Avl band, the preparation was shown to have three other main bands that migrated slower than Av 1. Of these three main bands, the protein with the fastest migration was identified as bacterioferritin elsewhere. The proteins on the other two bands, termed Upper and Middle, were suggested to be two different homopolymers with the same apparent subunit electrophoretic mobilities as the α- and β-subunits of Avl, respectively. By analysis of MALDI-TOF mass spectrometry, the Upper was identified as GroEL, which belongs to the heat shock protein 60 family, and the Middle was identified as glucose-6-phosphate isomerase （PGI）. In our preparation, anoxic native electrophoresis indicated that GroEL was composed of 14 identical subunits and that PGI was composed of 10 identical subunits. This is the first report of PGI, with so many subunits. The contaminating proteins in the Av 1 preparation, mainly GroEL and PGI, could be totally or partially removed from Av 1 if the shoulders and center of the elution peak were collected separately from the Sephacryl S-200 column and the center fraction was purified further by Q-Sepharose developed with an NaC1 concentration gradient. Thus, Avl with more than 90% purity was obtained. Obviously, this modified method is useful for the purification of mutant MoFe proteins with a high purity.

关键词： Azotobacter vinelandii chaperonin GroEL glucose-6-phosphate isomerase nitrogenase Av 1.

Activation In Vitro of Mutant MoFe Proteins from Azotobacter vinelandii by Reconstituent Solutions

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Journal of Integrative Plant Biology 2006年第5期48卷 567-572页

作者： huang-ping wang Ying Zhao Shao-Min Bian Hui-Na Zhou Zhi-Gang Zhang Jin-Mao Zhu Ju-Fu huang Bioengineering College Fujian Normal University Fuzhou 350007 China Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China College of Life Sciences Northwest University Xi＇an 710069 China

nifB-MoFe protein （nifB-Av1）, AnifE MoFe protein （△nifE Av1） and AnifZ MoFe protein （△nifZ Av1） were obtained by chromatography on DE52, Sephacryl S-300 and Q-Sepharose columns from nifB point-mutated, nifE deleted and nifZ deleted mutant stains （UW45, DJ35 and DJ194） of Azotobacter vinelandii Llpmann, respectively. When complemented with nltrogenase Fe protein （Av2）, AnifZ Av1 had partial activity and both nifB-Avl and △nifE Av1 had hardly any activity, but could be obviously activated by FeMoco extracted from wild-type MoFe protein （OP Av1） or △nifZ Av1. After being Incubated with excess O-phenanthrollne （O-phen） for 150 mln at 30 ℃ and subjected to chromatography on a Sephadex G-25 column In an Ar atmosphere, nifB- Av1C, △nifE Av1C and △nifZ Av1C were obtained, respectively. Based on a calculation of Fe atoms In the Ophen-Fe compound with ε 512nm = 11 100, lost Fe atoms of nifB-Av1, △nifE Av1 and △nifZ Av1 were estimated to be 1.35, 2.89 and 8.44 per molecule of protein, respectively. As a result of the Fe loss, △nifZ Av1 loses Its original activity. In the presence of both MgATP and Av2, these Fe-loslng proteins, but not the original proteins untreated with O-phen, could be significantly activated by reconstltuent solution （RS） composed of dlthlothreltol, ferric homocltrate, Na2S and Na2MoO4, or K2CrO4, or KMnO4. But In the absence of MgATP or Av2, the activation did not occur, with the exception that △nifZ AvlC was partially activated, and the activity was only 17%. These findings Indicate that：（I） △nifZ Avl with half P-cluster content Is somewhat different from FeMoco-deflclent nifB-Avl and ,△nifE Av1 with respect to protein conformation either before or after treatment with O-phen; （11） full activation of these proteins with RS requires pretreatment with O-phen and the simultaneous presence of MgATP and Av2.

关键词： activation in vitro by reconstituent solutions Azotobacter vinelandii mutant MoFe protein nifB^-,△nifE and △nifZ mutants.

CRYSTAL AND MOLECULAR STRUCTURE OF β-（Et4N）3 [Fe3（SPh）3Br3C13]

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Chinese Journal of Structural Chemistry 1985年第1期 72-74页

作者： huang Liangren Liu ping wang LinglingFujian Institute of Research on the Structure of Matter, Academia Sinica

Introduction. Previously, we have reported the compound α-（Et4N）3[Fe3（SPh）3-Br3Cl3]（Ⅰ）1with C2symmetry. An isomer（Ⅱ） of this compound, which has D3dsymmetry, is reported in this paper. Brow-green crystals ... 详细信息

关键词： Fe3 SPh Et4N CRYSTAL AND MOLECULAR STRUCTURE OF Br

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小春花醋酸乙酯部位的化学成分研究

中草药 2017年第5期48卷 884-887页

作者：羊波韩冰黄萍王鹏浙江省立同德医院浙江杭州310000 浙江中医药大学浙江杭州310000 浙江省肿瘤医院浙江杭州310000 浙江省金华市人民医院浙江金华321000

目的研究小春花(阴地蕨Botrychium ternatum的全草)醋酸乙酯部位的化学成分。方法利用反相硅胶柱色谱法、Sephadex LH-20凝胶柱色谱法等方法分离纯化,通过理化性质和波谱数据鉴定化合物的结构。结果从小春花的醋酸乙酯部位分离得到10个... 详细信息

目的研究小春花(阴地蕨Botrychium ternatum的全草)醋酸乙酯部位的化学成分。方法利用反相硅胶柱色谱法、Sephadex LH-20凝胶柱色谱法等方法分离纯化,通过理化性质和波谱数据鉴定化合物的结构。结果从小春花的醋酸乙酯部位分离得到10个化合物,分别鉴定为卫矛醇(1)、30-nor-21β-hopan-22-one(2)、山柰酚-7-O-α-L-鼠李糖苷(3)、槲皮素-3-O-α-L-吡喃鼠李糖苷(4)、槲皮素-7-O-β-D-葡萄糖苷(5)、山柰酚-3-O-α-L-鼠李糖苷(6)、槲皮素-3-α-L-鼠李糖-7-O-α-D-葡萄糖苷(7)、山柰酚-3,7-O-α-L-二鼠李糖苷(8)、12-二十三酮(9)、β-胡萝卜苷(10)。结论化合物1、3~7和9为首次从阴地蕨属植物中分离得到,化合物2、10为首次从小春花中分离得到。

关键词：小春花阴地蕨属卫矛醇山柰酚-7-O-α-L-鼠李糖苷 12-二十三酮

矩形窄缝通道低压低流速流动不稳定起始点实验研究

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原子能科学技术 2016年第11期50卷 1998-2002页

作者：王俊峰黄彦平王艳林中国核动力研究设计院中核核反应堆热工水力技术重点实验室四川成都610041

针对截面为40mm×3mm的竖直矩形窄缝通道,在低压低流速条件下,对其流动不稳定起始点(OFI)进行了可视化实验研究。观察到了OFI出现时通道内对应的汽泡以及流型分布等微观特征;基于可视化观察结果,定性分析了OFI出现的内在机理;获得了主... 详细信息

针对截面为40mm×3mm的竖直矩形窄缝通道,在低压低流速条件下,对其流动不稳定起始点(OFI)进行了可视化实验研究。观察到了OFI出现时通道内对应的汽泡以及流型分布等微观特征;基于可视化观察结果,定性分析了OFI出现的内在机理;获得了主要热工水力参数对OFI的影响规律;采用本实验获得的数据,对现有的OFI预测关系式进行了定量评价。结果表明:以饱和点参数为变量得到的关系式基本都能与本实验数据较好地吻合。

关键词：矩形窄缝通道流动不稳定起始点低压低流速可视化

Quickly obtaining densely dispersed coherent particles in steel matrix and its related mechanical property

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 111-118页

作者： Xiaoxiao wang Qingsong huang School of Chemical Engineering Sichuan UniversityChengdu 610065China

Densely distributed coherent nanoparticles(DCN)in steel matrix can enhance the work-hardening ability and ductility of steel *** the routes to this end can be generally classified into the liquid-solid route and the solid-solid ***,the formation of DCN structures in steel requires long processes and complex *** far,obtaining steel with coherent particle enhancement in a short time remains a bottleneck,and some necessary steps remain ***,we show a high-efficiency liquid-phase refining process reinforced by a dynamic magnetic ***-Y-Mn-O particles had an average size of around(3.53±1.21)nm and can be obtained in just around 180 *** small nanoparticles were coherent with the matrix,implying no accumulated dislocations between the particles and the steel *** findings have a potential application for improving material machining capacity,creep resistance,and radiation resistance.

关键词： ferritic steels coherent particles microstructure compression test work hardening

A promising approach for quantifying focal stroke modeling and assessing stroke progression:optical resolution photoacoustic microscopy photothrombosis

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Neural Regeneration Research 2025年第7期20卷 2029-2037页

作者： Xiao Liang Xingping Quan Xiaorui Geng Yujing huang Yonghua Zhao Lei Xi Zhen Yuan ping wang Bin Liu Faculty of Health Sciences University of MacaoMacao Special Administrative RegionChina Center for Cognitive and Brain Sciences University of MacaoMacao Special Administrative RegionChina Department of Biomedical Engineering Southern University of Science and TechnologyShenzhenGuangdong ProvinceChina State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipaMacao Special Administrative RegionChina Department of Emergency Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral ***,these methods often require complex systems and the effect of age on cerebral embolism has not been adequately studied,although ischemic stroke is strongly *** this study,we propose an optical-resolution photoacoustic microscopy-based visualized photothrombosis methodology to create and monitor ischemic stroke in mice simultaneously using a 532 nm pulsed *** observed the molding process in mice of different ages and presented age-dependent vascular embolism ***,we integrated optical coherence tomography angiography to investigate age-associated trends in cerebrovascular variability following a *** imaging data and quantitative analyses underscore the differential cerebrovascular responses to stroke in mice of different ages,thereby highlighting the technique's potential for evaluating cerebrovascular health and unraveling age-related mechanisms involved in ischemic strokes.

关键词： age-dependent cerebral cortex ischemic stroke mouse model optical coherence tomography angiography photoacoustic microscopy photothrombosis vascular imaging

SYNTHESIS AND STRUCTURE OF[Et4N]3[FE3（SPh）3Br3Cl3]

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Chinese Journal of Structural Chemistry 1984年第2期 135-137页

作者： Liu ping huang Liangren wang Lingling Kang Beisheng and Lu JiaxiFujian Institute of Research on the Structure of Matter, Academia Sinica

The title compound was synthesized and its structure solved. The formula is [Et4N]3[Fe3(SPh)3Br3Cl3]. M=1231.95, monoclinic, space group C2/c, a=24.569(4), b=13.504(2), c=18.348.(3)A, β=110.78(1)°, V=5691(3)A3, Z=4, Dm= 1.41, Dc=1.44-g/cm3. The flat structure of the anion has. a planar [Fe3S3] ring and three phenyl groups. Statistical distribution of chlorine and bromine atoms on two sides of the [Fe3S3] plane results in a C2 symmetry of the anion.

关键词： 110 FE3 SPh SYNTHESIS AND STRUCTURE OF[Et4N Th Br Cl