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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.

Energy absorption behaviors of a novel buffer lander-leg with Yoshimura core

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Chinese Journal of Aeronautics 2024年第4期37卷 333-342页

作者： Yan XU He huang Chao ZHANG Rongji fu School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical UniversityXi’an 710072China

In the current soft-landing system,the lander-leg and the buffer are two independent parts which may cause weight *** traditional mechanical buffers also have their own shortcomings such as small buffer stroke and being non-reusable.A Novel Buffer Lander-leg with Yoshimura core (NBLY) is proposed in this paper,inspired by the Buckling Restrained Brace(BRB).The design details of NBLY and parameter definitions of the core are *** finite element analysis modes have been employed to analyze the nonlinear mechanical behaviors of NBLY subjected to the cyclic *** with four different core styles of hexagon,octagon,dodecagon and hexadecagon are analyzed and *** restraining ratio and cumulative dissipation energy ratio have been obtained to evaluate the energy absorption *** results show that the origami pattern has significant influences on the deformation ductility,plastic energy absorbing and axial load transferring to the *** NBLY with octagon core has outstanding properties,especially the hysteretic energy dissipation and enhancement of compression *** interaction mechanism between the core and encasing member constrains the deformation extensions and contributes to the frictional energy dissipation of the *** paper provides a new conceptual design of buffer lander-leg for soft-landing *** can realize the reuse function as a buffer lander-leg with better loading-bearing and energy absorption behaviors.

关键词： Lander-leg structure Origami Energy absorption Cyclic loading Finite element analysis

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Strip method to construct a two-dimensional quasilattice witheight-fold symmetry

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Chinese Physics B 2024年第9期33卷 462-465页

作者： Weishen huang Xiujun fu School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

Based on the substitution rule and symmetry, we propose a method to generate an octagonal quasilattice consisting ofsquare and rhombus tiles. Local configurations and Ammann lines are used to guide the growth of the tiles in a quasiperiodicorder. The structure obtained is a perfect eight-fold symmetric quasilattice, which is confirmed by the radial distributionfunction and the diffraction pattern.

关键词： quasicrystals eight-fold symmetry Ammann–Beenker tiling

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Genetic mapping of plasma proteome on brain structure

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Journal of Genetics and Genomics 2024年第7期51卷 774-777页

作者： Shengyi Ma Fengzhe Xu Yuanqing fu ju-Sheng Zheng fudan University Shanghai 200433China School of Life Sciences Westlake UniversityHangzhouZhejiang 310030China Westlake Center for Intelligent Proteomics Westlake Laboratory of Life Sciences and BiomedicineHangzhouZhejiang 310030China

The emergence of high-throughput techniques for proteomics measurement has led to an increasing number of proteogenomic studies that aim to reveal protein quantitative trait loci(pQTL)based on large cohorts(Suhre et a... 详细信息

关键词： mapping structure throughput

Multiple regulatory roles of the transfer RNA-derived small RNAs in cancers

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Genes & Diseases 2024年第2期11卷 597-613页

作者： Yu Zhang Xinliang Gu Yang Li Yuejiao huang Shaoqing ju Medical School of Nantong University Nantong UniversityNantongJiangsu 226001China Department of Laboratory Medicine Affiliated Hospital of Nantong UniversityNantongJiangsu 226001China Research Center of Clinical Medicine Affiliated Hospital of Nantong UniversityNantongJiangsu 226001China Department of Medical Oncology Affiliated Hospital of Nantong UniversityNantongJiangsu 226001China

With the development of sequencing technology,transfer RNA(tRNA)-derived small RNAs(tsRNAs)have received extensive attention as a new type of small noncoding *** on the differences in the cleavage sites of nucleases on tRNAs,tsRNAs can be divided into two categories,tRNA halves(tiRNAs)and tRNA-derived fragments(tRFs),each with specific subcellular ***,the biogenesis of tsRNAs is tissue-specific and can be regulated by tRNA *** this review,we first elaborated on the classification and biogenesis of *** summarizing the latest mechanisms of tsRNAs,including transcriptional gene silencing,post-transcriptional gene silencing,nascent RNA silencing,translation regulation,rRNA regulation,and reverse transcription regulation,we explored the representative biological functions of tsRNAs in ***,this review summarized the clinical value of tsRNAs in cancers,thus providing theoretical support for their potential as novel biomarkers and therapeutic targets.

关键词： Biogenesis Biological function Cancer Mechanism Therapeutic strategy tsRNAs

Synthesis,structure,and luminescence properties of melilite Dy^(3+):Lu_(x)CaLa_(0.98-x)Ga_(3)O_(7) phosphors for use in yellow light-emitting devices

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Journal of Rare Earths 2024年第8期42卷 1489-1495,I0003页

作者： Yunyun Liu Chuanxin huang Meng Wang Xihu Wang Yan Wang ju Gao School of Opto-Electronic Engineering Zaozhuang UniversityZaozhuang277160China Key Laboratory of functional Materials and Devices for Informatics of Anhui Educational Institutions Department of PhysicsFuyang Normal UniversityFuyang236037China Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002.China

Dy^(3+) and Lu^(3+) co-doped CaLaGa_(3)O_(7) phosphors were prepared via high-temperature solid-phase *** electronic structures of LuxCaLa_(0.98-x)Ga_(3)O_(7) were investigated by the first-principles *** influence of Lu^(3+) on yellow light emission was studied using X-ray diffraction(XRD)and photoluminescence(PL) *** XRD results indicate that compared to Dy^(3+):CaLaGa_(3)O_(7),the cell parameters of Dy^(3+):LuCaLaGa_(3)O_(7) tend to decrease,which is due to the smaller radius of Lu^(3+).When pumped by blue GaN laser diode(LD),the emission peaks of phosphors with different Lu^(3+)doping concentrations in the visible region are similar,with the strongest peak at 574 nm in the yellow light region,which is sensitive to human *** optimal doping concentration of Lu^(3+) is confirmed to be1 at%,when all emission spectra and measured fluorescence lifetimes are taken into ***,the optimal phosphor composition Dy^(3+):Lu_(x)CaLa_(0.98-x)Ga_(3)O_(7)(x=0.01) has an internal quantum efficiency(IQE) of 46.94% and an external quantum efficiency(EQE) of 15.19%.Most notably,the prepared phosphor demonstrates excellent thermal stability and a high activation energy(0.203 eV).In addition,the International Illumination Commission color coordinates of the Dy^(3+):LuxCaLa_(0.98-x)Ga_(3)O_(7) phosphors are in the yellow light *** above analysis indicates that the Dy^(3+):LuxCaLa_(0.98-x)Ga_(3)O_(7)(x=0.001)phosphor has promising application prospects in yellow light-emitting devices.

关键词： Dy^(3+):Lu_(x)CaLa_(0.98-x)Ga_(3)O_(7)phosphors Yellow emission Structure characteristics Luminescent properties Rare earths

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Solar fuel production through concentrating light irradiation

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Green Energy & Environment 2024年第10期9卷 1550-1580页

作者： Yiwei fu Yi Wang Jie huang Kejian Lu Maochang Liu International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow Xi'an Jiaotong University Suzhou Academy of Xi'an Jiaotong University

The climate crisis necessitates the development of non-fossil energy sources. Harnessing solar energy for fuel production shows promise and offers the potential to utilize existing energy infrastructure. However, solar fuel production is in its early stages of development, constrained by low conversion efficiency and challenges in scaling up production. Concentrated solar energy(CSE) technology has matured alongside the rapid growth of solar thermal power plants. This review provides an overview of current CSE methods and solar fuel production, analyzes their integration compatibility, and delves into the theoretical mechanisms by which CSE impacts solar energy conversion efficiency and product selectivity in the context of photo-electrochemistry, thermochemistry, and photo-thermal co-catalysis for solar fuel production. The review also summarizes approaches to studying the photoelectric and photothermal effects of CSE. Lastly, it explores emerging novel CSE technology methods in the field of solar fuel production.

关键词： Concentrated solar energy Solar fuel Photo-electrochemistry Thermochemistry Photo-thermal co-catalysis