Cloning and heterologous expression of a novel GH10 xylanase gene from Hypocrea orientalis EU7-22

木聚糖酶是降解半纤维素最主要的酶,对于开发可再生生物能源具有重要的应用价值。分别以东方肉座菌(HyPOCrEA OrIEnTAlIS)Eu7-22的基因组dnA和C dnA为模板,利用染色体步移和PCr技术首次克隆获得该菌gH10家族木聚糖酶Ⅲ的基因(XynⅢ),并对其进行生物信息学分析。结果表明:该基因全长1283 bP(gXynⅢ),含有3个内含子;CdS序列为1044 bP(CXynⅢ),编码347个氨基酸,n端含有一个16 AA的信号肽序列;XynⅢ氨基酸序列与TrICHOdErMA PSEudOkOnIngII的EndOXylAnASE具有较高的同源性。经生物信息学分析,XynⅢ成熟蛋白可能含有18个n-糖基化位点,其理论等电点(P I)为6.14,蛋白质分子质量为36.55 ku,属于亲水性蛋白;SWISS-MOdEl建模预测,XynⅢ成熟蛋白中含有11个α螺旋,其核心结构为8个β折叠片围成一个柱状结构。同时将编码成熟蛋白的基因片段MXynⅢ与P PIC9k质粒连接构建表达载体后转化毕赤酵母,对重组子表达产物进行酶活检测显示该基因能在毕赤酵母中表达有生物活性的XynⅢ并分泌到胞外,发酵液中的木聚糖酶活在诱导培养168 H后可达到127.5 Iu/M l。Endo-1,4-xylanase( E.C.3.2.1.8) is the major enzyme to the conversion of hemicelluloses into xylo-oligosaccharide.In this research,a novel GH10 xylanase Ⅲ( xyn Ⅲ) gene was cloned from Hypocrea orientalis EU7-22 by chromosome walking and PCR.The results showed that the DNA fragment( 1283 bp) encoding xynⅢ( gxynⅢ) contained three introns.The CDS of xynⅢ( cxynⅢ) encoded 331 amino acids of putative mature protein and a 16 aa signal in N terminator.The amino acid sequence of xynⅢ is highly homologous with the endoxylanase of Trichoderma pseudokoningii.The bioinformatics analysis showed that the theoretical isoelectric point and the molecular weight of putative mature protein of XYNⅢ were 6.14 and 36.55 ku,respectively.It is a soluble hydrophilic protein containing 18 N-glycosylation sites.The 3D structure predicted with SWISS-Model showed that XYNⅢ protein contained11 alpha helices and 8 extended strands.A recombinant plasmid p PIC9K-xynⅢ was constructed and then transformed into Pichia pastoris.The transformant identified by PCR was induced to produce XYNⅢ enzyme with 1% methanol.And after 168 hours induced expression,the produced crude enzyme was detected to reach a high enzymatic activity of 127.5 IU / m L.国家自然科学基金(21303142;31170067); 福建省海洋高新产业发展专项项目(闽海洋高新[2014]25号); 厦门市海洋经济发展专项资金项目(14GZP59HJ29

Research Progress of α-Glucuronidase, an Enzyme for Degrading Hemicellulose Side-Chain

半纤维素是自然界中最丰富的可再生资源之一,将半纤维素降解为单糖并转化为燃料或化学品一直是科学界研究的热点。半纤维素是由木糖基主链以及α-葡萄糖醛酸等侧链共同组成的异质多聚体。α-葡萄糖醛酸酶是半纤维素完全降解过程中的关键酶之一,能够水解4-O-甲基葡萄糖醛酸与木糖之间的α-1,2-糖苷键。本文综述了α-葡萄糖醛酸酶的分类、催化机制及晶体结构、酶学性质和基因克隆表达等方面的研究进展,同时对该研究进行了展望。Hemicellulose is one of the most abundant renewable resources in nature.The bioconversion of hemicellulose into biofuels or chemicals is a research hotspot in the world.Hemicellulose consists of a backbone of xylan residues and some branches like glucuronic acid.α-Glucuronidase, which is capable to hydrolysis the α-1,2-glycosidic bond between xylan and glucuronic acid, is one of the key enzyme to degrade hemicellulose completely.The recent research progresses on catalysis mechanism, structure, charaterization, and gene cloning of α-glucuronidase are summarized in this paper.国家自然科学基金(31170067;21303142); 国家重点基础研究发展计划(973计划;2010CB732201); 福建省自然科学基金(2012J05029); 农业部“引进国际先进农业科学技术”项目(2013-Z70

Three-Dimensional Fluorescence Technique Coupled with Chemometric Second-Order Calibration Method for Simultaneous Detection of Thiabendazole and Fuberidazole in Red Wine

噻菌灵和麦穗宁是被广泛应用于预防治疗蔬菜水果病害的苯并咪唑类杀菌剂,二者的荧光光谱重叠严重,常规的荧光方法难以实现同时直接定量分析。本文将激发发射三维荧光技术分别与平行因子分析(PArAfAC)算法和交替三线性分解(ATld)算法相结合直接用于定量分析红葡萄酒中噻菌灵和麦穗宁的残留含量。当体系主成分数为3时,ATld和PArAfAC获得预测样品中噻菌灵和麦穗宁的平均回收率分别为(105.8±2.7)%、(102.1±10.1)%和(102.4±7.6)%、(103.1±9.5)%。本方法可简单、快速、经济、同时地分析红葡萄酒中噻菌灵和麦穗宁含量。Thiabendazole(TBZ) and fuberidazole(FBZ) are a class of benzimidazole fungicides and have been widely applied to protect vegetables and fruits.Conventional fl uorescence spectrum analysis method can hardly simultaneously detect TBZ and FBZ due to their serious spectral overlap.The simultaneous determination of TBZ and FBZ in red wine by excitation-emission fluorescence matrices(EEMs) combined with parallel factor analysis(PARAFAC) and alternating tri-linear decomposition(ATLD) was developed in this study.The prediction recoveries of TBZ and FBZ in the prediction set by PARAFAC and ATLD were(105.8±2.7)%,(102.1±10.1)% and(102.4±7.6)%,(103.1±9.5)% respectively,when the principal component number was 3.The method is simple,fast,low-cost,and suitable for the simultaneous determination of TBZ and FBZ in red wine.国家自然科学基金项目(21127005;21375111); 福建省科技重点项目(2009Y0046

Identification and analysis of odor of patients with exterior syndrome based on medical electronic nose

目的:运用自主研发的医用电子鼻探讨表证患者口腔呼气的气味图谱特征及气味识别准确率。方法:选择表证青年患者150例和健康青年人200名,运用基于薄膜型气体传感器阵列技术的医用电子鼻(nAnOfIlM-EnOSE MEdICAl001)采集口腔呼气的气味图谱,以响应曲线的振幅和上升斜率作为曲线特征,分析表证患者及其寒热病性的图谱特征,并进行判别分析。结果:表寒证和表热证患者的气味图谱响应曲线A、b、d、E、g、H的振幅和上升斜率均显著高于健康学生(P<0.01)。表热证患者的气味图谱响应曲线A、b、d、E、H的振幅和上升斜率均显著高于表寒证患者(P<0.05,P<0.01),表热证患者的气味图谱响应曲线g的振幅显著高于表寒证患者(P<0.01)。判别分析显示对健康青年人、表寒证青年患者、表热证青年患者口腔呼气的识别准确率分别为90.5%、86.5%、88.0%,对全部案例的识别准确率为89.1%。结论:表证青年患者口腔呼气的气味较健康青年人浓烈,且表热证青年患者气味变化较表寒证青年患者更明显,本医用电子鼻能够较为敏感和准确地辨识表证青年患者口腔呼气的气味特征及其寒热病性。医用电子鼻技术的发展可为中医嗅诊客观化研究提供手段和方法。Objective: to explore the odor response pattern characteristics of oral breath of patients with exterior syndrome and accuracy rates of odor identiication by medical electronic nose which was independent research and development.Methods: 150 young patients with exterior syndrome and 200 healthy young students were observed.Odor response patterns of oral breath were collected by the electronic nose(Nanoilm-Enose Medical001) based on a ilm of gas sensor array.The amplitude and rising slope of response curves were selected as curve characteristics to analyze pattern characteristics of exterior syndrome including exterior cold syndrome and exterior heat syndrome,and discriminant analysis was done.Results: In odor response patterns of patients with exterior cold syndrome and with exterior heat syndrome,the amplitudes and rising slopes of response curve A,B,D,E,G and H were signiicantly higher than those of healthy students(P<0.01).In odor response patterns of patients with exterior heat syndrome,the amplitudes and rising slopes of response curve A,B,D,E and H were signiicantly higher than those of patients with exterior cold syndrome(P<0.05,P<0.01),and the amplitude of response curve G was signiicantly higher than that of patients with exterior cold syndrome(P<0.01).Discriminant analysis showed that the accuracy rate of oral breath identiication of healthy students,patients with exterior cold syndrome and patients with exterior heat syndrome was 90.5%,86.5% and 88.0% respectively,and the accuracy rate of all cases was 89.1%.Conclusion: The odors of oral breath of patients with exterior syndrome were signiicantly stronger than those of healthy people.The odors of patients with exterior heat syndrome were signiicantly stronger than those of patients with exterior cold syndrome.This medical electronic nose could distinguish odor characteristic of oral breath of patients with exterior syndrome sensitively and accurately;and it could also distinguish odor characteristic of exterior cold syndrome from exterior heat syndrome.The development of medical electronic nose could provide a kind of new means for the study on the objectiication of TCM smelling examination.国家自然科学基金项目(No.30901899); 福建省教育厅A类项目(No.JA09132)~

Function of a methyl-accepting chemotaxis protein Tlp1 in Azorhizobium caulinodans ORS571

【目的】考察茎瘤固氮根瘤菌中趋化基因簇上游的受体蛋白Tlp1编码基因的突变表型,初步探究其功能机理。【方法】利用同源重组和三亲本接合转移的方法构建突变株,在TY培养基中测定生长情况,半固体平板法观察趋化圈,刚果红固体培养基观察胞外多糖和次生代谢产物的分泌,乙炔还原法测定菌株的固氮酶活性。【结果】与野生型菌株相比,tlp1突变株的生长速率没有影响。在以甘油为碳源的L3半固体平板上突变株的趋化圈变小,其回补菌株能部分回补趋化能力。突变株的胞外多糖分泌与野生型没有区别,但其次生代谢产物黑色素出现的时间比野生型稍早。在固氮酶活性测定中,发现突变株酶活性明显比野生型降低,回补菌株能够部分回补。【结论】茎..

山东花生根瘤菌遗传多样性及高效共生固氮菌株的筛选

山东省是我国花生种植和生产的主要地区，其花生根瘤菌遗传多样性和高效共生菌株种质资源较为丰富。为揭示山东省花生根瘤菌种群结构和遗传多样性，本研究从山东省10个县市采集新鲜的花生根瘤分离出根瘤菌，对菌株的16S rRNA基因、持家基因（recA、atpD、glnII）序列进行系统发育分析以确定根瘤菌的系统发育地位，同时对共生基因nifH、nodC序列进行系统发育分析，并通过温室盆栽接种实验筛选高效共生固氮根瘤菌菌株。 从10个县市采样点共分离到345株花生根瘤菌菌株，通过持家基因recA序列分析选定22株代表菌株。对代表菌株的16S rRNA基因与持家基因MLSA系统发育分析表明，所分离到的菌株分布于Bradyrhizobium的B. liaoningense和B. yuanmingense、B. arachidis和一个潜在新种群。共生基因nifH和结瘤基因nodC系统发育分析表明固氮基因和结瘤基因高度保守，系统发育关系较近，但与16S rRNA、持家基因系统发育存在较大差异，表明花生根瘤菌种群之间存在共生基因的横向转移。温室盆栽实验表明代表菌株均能与花生有效结瘤固氮，高效固氮菌株YIC61059在大田小区实验中能够对花生起到显著的促生增产作用。 根瘤菌与土壤因子相关性分析表明：有效氮、全氮和有机质是影响山东省花生根瘤菌种群分布的主要因素。低磷、高氮的土壤有利于B. liaoningense的分布，高水平的全氮和有机质有利于B. yuanmingense的分布，高磷和低碱的土壤对潜在新种群影响较大。 综上所述，山东省花生根瘤菌具有丰富的遗传多样性和种质资源。该地区的花生根瘤菌具有较好的结瘤和共生固氮能力，pH、速效磷和速效钾是影响山东省花生根瘤菌分布的主要因素，本研究筛选出的高效共生固氮花生根瘤菌YIC61059促生增产效果明显，具有良好的应用前景。 &nbsp;</div

DOCUMENT IMAGE BINARISATION BASED ON BACKGROUND ESTIMATION AND EDGE DETECTION

为提高文档图像在对比度低、光照不均、大块噪声等复杂图像背景下二值化效果,提出一种背景估计与边缘检测相结合的图像二值化方法.该方法先利用Sauvola算法有效地估计图像的背景,并在此基础上,结合改进的Canny算法获取边缘变化信息,利用基于局部阈值的策略进行二值化.实验结果表明,该算法取得了较好的二值化效果,在开放的DIBC0 2011数据集上测试,其性能与Otsu、Niblack、Sauvola经典方法相比有大幅提高,其F值比ICDAR2011二值化竞赛中第一名的算法略有提高.To enhance the binarisation effect of image documents in complex image background of low contrast,uneven illumination and bulk noise, etc.,we present an image binarisation method combining the background estimation and edge detection. Firstly, Sauvola' s algorithm is used in the method to estimate image background effectively. On this basis, the improved Canny edge detection algorithm is combined to get edge variation information. At last the local threshold-based policy is employed for binarisation. Experimental results demonstrate that the algorithm achieves better binarisation effect,test is carried out on open Document Image Binarisation Contest (DIBCO) 2011 dataset, the performance of the proposed method has promising improvement than classic methods of Otsu,s, Niblack, s and Sauvola's, its F value is slightly higher than that of the No. 1 algorithm in ICDAR2011 binarisation contest

Research on Image Remap Algorithm Optimization Based on OpenCL

图像重映射(Remap)算法是典型的图像变化算法。在图像放缩、扭曲、旋转等领域有着广泛的应用。随着图片规模和分辨率的不断提高，对图形映射算法的性能提出了越来越高的要求。本文在充分考虑不同GPU平台硬件体系结构差异的基础上，系统研究了在OpenCL框架下图像映射(Remap)算法在不同GPU平台上的高效实现方式。并从片外内存访存优化，向量化计算，减少动态指令等多个优化角度考察了不同优化方法在不同GPU平台上对性能的影响，提出了在不同GPU平台间实现性能移植的可能性。实验结果表明，优化后的算法在不考虑数据传输时间的前提下，在AMD HD5850 GPU上相对于CPU版本取得114.3~491.5倍的加速比，相对于CUDA版本(现有GPU算法的实现)得到1.01~1.86的加速比，在NIVIDIA C2050 GPU上相对CPU版本取得100.7~369.8倍的加速比，相对于CUDA版本得到0.95~1.58的加速比。有效验证了本文提出的优化方法的有效性和性能可移植性。 As a typical algorithm for image transformation, remap algorithm is widely used in image zooming, warping, rotating and some others. With continuous increase of image’s scale and resolution, higher performance of graphic mapping algorithm has been more and more demanded. Taking full account of the differences of the hardware architectures on different GPU platforms, it is systematically studied in this paper that how remap algorithm based on OpenCL can run effectively on different GPU platforms. By applying memory access optimization of global memory, vectorization calculation, reducing judgments branch and some other optimization methods, we investigated the effects of different optimization on different platforms and suggested the possibility of realizing cross-platform portability. Experimental results showed that without counting the data transfer time, the speedup-ratio is 114.3~491.5 times for AMD HD5850 GPU to CPU version, and 1.01~1.86 times to CUDA version (with present GPU algorithm), and for NIVIDIA C2050 GPU, the speedup-ratio is 100.7~369.8 times to CPU and 0.95~1.58 times to CUDA. These well proved the validity and portability of the optimization methods proposed in this paper

周盘式制动器热-应力耦合特性的分析探究

以东风Q/ZEZPSCZ02—2018型周盘式制动器为研究对象，探究该款新型制动器的热-应力耦合，分析了其安全性能。基于SolidWorks建立的三维模型，借助有限元分析软件Ansys Workbench，对周盘式制动器建立热-应力耦合；设置汽车持续制动和颠簸路段制动的工况条件，分析其等效弹性应变、应力和温升情况，探究其之间的映射关系；通过模型仿真，得到温度云图、应力云图和等效弹性应变云图。经分析可知，温度上升趋势先急后缓，最大应力和等效弹性应变均位于内蹄双凸轮处；通过台架实验数据对比发现，结果在误差所允许的范围内。为后续的工程设计、散热机理研究、检测维修提供了参考依据