葡萄色顶枝瑚菌中矿质元素及氨基酸含量的测定

采用原子吸收分光光度法和FDBN柱前衍生高效液相色谱等方法测定了葡萄色顶枝瑚菌中的矿质元素、氨基酸和蛋白质的含量。矿质元素K、Ca、Mg、Cu、Zn、Fe的含量分别是 :4 2 .5 0 0 0mg/g、0 .90 0 0mg/g、0 .4 1 3 0mg/g、0 .0 1 1 2mg/g、0 .0 64 3mg/g、0 .0 3 1 7mg/g、0 .0 73 7mg/g;蛋白质含量为 2 8.1 7% ;氨基酸总量为 2 2 6.91mg/g,其中七种必需氨基酸含量占氨基酸总量的 4 9.2 5 %     

黑尾近红鲌含肉率及肌肉营养成分分析

测定了长江上游特有鱼类黑尾近红的含肉率及其肌肉生化成分和能值。结果表明 :黑尾近红的含肉率为 70 74 % ;其肌肉生化成分 (鲜重百分比 )水分含量为 80 97%、蛋白质 15 92 %、脂肪 1 11%、灰分 1 0 1%、无氮浸出物 0 99%、比能值 4 37kJ/g及E/P 2 7 4 5kJ/g。肌肉生化成分含量与体长变化无明显关系。肌肉中含有 17种氨基酸 ,总量为 6 9 0 7% (干重百分比 ) ;9种人体必需氨基酸总量是 34 81% ,必需氨基酸占氨基酸总量比例为5 0 39% ;四种鲜味氨基酸含量为 2 6 94 % ;必需氨基酸指数 (EAAI)是 6 3 6 4。缬氨酸 ,苏氨酸和异亮氨酸为限制性氨基酸。     

陕西三种特种稻米氨基酸及品质分析

以陕西洋县产茉莉香米、红香米和绿香粳米等 3种特种稻米为材料 ,分析了氨基酸及其它品质指标。结果表明 ,茉莉香米、红香米和绿香粳米均含有 1 7种氨基酸 ,氨基酸总含量 (mg/ 1 0 0 g)分别为 730 0、72 70、74 90 ;除Trp外 ,7种必需氨基酸占氨基酸总量分别为 34 .6 %、34 .5 %、34 .8% ;Lys含量 (mg/ 1 0 0g)分别为 5 5 0、5 2 0、5 30 ;粗蛋白质含量分别是 9.94 %、9.2 3%、8.5 2 % ;Cu含量 (mg/ 1 0 0g)分别是 0 .6 2、0 .94、0 .79;Zn含量 (mg/ 1 0 0 g)分别是 1 .99、1 .75、2 .0 2 ;Fe含量 (mg/ 1 0 0 g)分别是 1 .5 5、3.70、4 .5 0 ;直链淀粉含量分别是 1 5 .6 %、3.7%、1 5 .1 % ;胶稠度分别是 33mm、4 0 .6mm、78mm ;糊化温度分别是 6 .1级、6 .8级、7级 ;水分含量分别是 1 1 .2 7%、1 1 .5 5 %、1 2 .5 2 %。这 3种特种稻品质较优 ,具有推广价值     

双向凝胶电泳分析小鼠子宫内膜胚泡着床点和着床旁组织蛋白质组

目的 :研究小鼠子宫内膜胚泡着床点和着床旁蛋白质表达图谱及其差异。方法 :用固相pH梯度双向凝胶电泳分离 5d .p .c .(dayspostcoitum)小鼠子宫内膜胚泡着床点和着床旁总蛋白 ,同时分离同龄未交配小鼠子宫内膜总蛋白 ,银染显色 ,PDQuest 2DE软件分析。结果 :图像分析测得三块胶的匹配率达 74 5 %以上 ,在等电点pI 3～ 1 0、分子量 1 4 4～ 75 4kDa范围内分离得未交配小鼠子宫内膜蛋白点大约 81 0个 ,受孕小鼠子宫内膜胚泡着床旁和着床点蛋白质点分别大约为 95 0个和 1 0 4 0个 ,其中至少 90个蛋白点在三种不同的生理状态间有 2倍以上的量变。结论 :在“着床窗口期” ,小鼠子宫内膜特别是着床位点内膜合成更多的蛋白质 ,以适宜胚泡成功地植入。     

薏苡仁蛋白质组分研究

目的：对药食两用功能的薏苡仁蛋白质四类组分和氨基酸含量进行分析。方法：采用旋光法、索氏提取法、烘干法、马弗炉法分别进行淀粉、粗脂肪、水分和灰分的测定;采用顺序抽提法依次进行清蛋白、球蛋白、醇溶蛋白和谷蛋白的提取,用Brandford和凯式定氮法进行蛋白质含量分析;采用氨基酸分析仪进行氨基酸含量测定。结果：薏苡仁总蛋白含量为14．17％,其中清蛋白、球蛋白、醇溶蛋白和谷蛋白含量分别为0．20、0．88、6．34和5．30mg／100mg鲜重,分别占总蛋白质含量的1．43％、6．20％、44．74％和37．38％;薏苡仁粉经酸水解后共检测到15种氨基酸,除Trp外,人体必需氨基酸和半必需氨基酸均有检测到;各氨基酸含量也存在着差异,含量最高的为Glu（3．59mg／100mg）,含量最低的为Met（0．17mg／100mg）。结论：薏苡仁蛋白中醇溶蛋白和谷蛋白含量较丰富,为今后进一步开发薏苡仁功能食品提供了理论数据。     

黄鳝血清和体表粘液蛋白的比较研究

本文用反相高效液相色谱法测定了黄鳝血清和体表粘液蛋白的氨基酸种类和含量,比较了二者的氨基酸组成变化。结果表明：二者都含有17种氨基酸,血清的氨基酸总量为397．11mg／l00ml,体表粘液蛋白的氨基酸总量为259．29mg／l00m1,血清与粘液蛋白中氨基酸含量差异最大的是蛋氨酸、半胱氨酸。应用SDS—PAGE分析和比较了血清和体表粘液蛋白的分子量大小及特有区带效,黄鳝血清与体表粘液蛋白分子量相同的蛋白区带数为2条,其分子量大小分别为19．5kDa、96．0kDa。其中血清的特有蛋白带为18条,体表粘液的特有蛋白带为8条。此外,对二者的相关性和体表粘液特异性的免疫机制作了探讨。     

胞浆接头蛋白Dok5的表达及生物信息学分析

[目的]构建携带小鼠Dok5基因及其PH、PTB结构域的原核表达载体,并表达对应GST融合蛋白。[方法]从小鼠脑组织提取总RNA,逆转录后经PCR扩增、酶切、连接及转化大肠杆菌DH5α,构建携带Dok5全长(FL)、PTB、PH结构域的原核表达质粒,经酶切及测序鉴定之后,转化大肠杆菌BL21,经IPTG诱导表达蛋白,再利用Glutathion Sepharose 4B亲和层析柱纯化得到融合蛋白,并通过Western Blotting检测其与相应抗体的反应性。利用生物信息学相关软件(ClustalW2、ProtParam、ProtScale、NetPhos 2.0 Server、SOPMA、Swissmodel)预测Dok5蛋白的理化性质和磷酸化位点以及二、三级结构。[结果]构建了小鼠Dok5 FL、PH、PTB的原核表达质粒,并得到了浓度分别为0.3 mg/ml、0.6 mg/mL、1 mg/mL的pGEX 6p-1-Dok5 FL、PH、PTB蛋白,其中Dok5 FL融合蛋白与相应抗体具有良好的反应性。Dok5长度为921 bp,编码306个氨基酸,在人、鼠、猴中高度保守。Dok5相对分子质量为35.453 kDa,理论pI为9.0,包含50个潜在磷酸化位点。[结论]分别得到了63 kDa、39 kDa、37 kDa的Dok5 FL、PH、PTB的GST融合蛋白,预测Dok5是一种亲水性的不稳定蛋白。     

厚颌鲂含肉率及生化成分的分析

研究了长江上游特有鱼类厚颌鲂的含肉率及其肌肉生化成分和能值。结果表明 :厚颌鲂的含肉率为72 72 % ;其肌肉生化成分 (鲜重百分比 ) :水分含量为 79 2 6%、蛋白质 16 82 %、脂肪 2 10 %、灰分 1 0 8%、无氮浸出物 0 73 %、比能值 4 93KJ/g及E/P2 9 3 3KJ/g。肌肉生化成分含量与体长变化无明显关系。经单因素方差分析 5— 6月份样品与 10月份样品在脂肪和无氮浸出物含量上有显著差异 (P <0 0 5)。肌肉中含有 17种氨基酸 ,总量为69 54% (干重百分比 ) ;9种人体必需氨基酸总量是 3 3 0 7% ,占氨基酸总量比例为 47 55% ;必需氨基酸指数 (EAAI)是 61 75。缬氨酸和异亮氨酸为限制性氨基酸 ;四种鲜味氨基酸含量为 5 85% (鲜重百分比 )。     

油松、白皮松和青杄花粉营养成分的研究

通过对我国有巨大生产量和应用潜力的油松、白皮松和青木千花粉的 1 8种氨基酸、蛋白质、维生素A、维生素E、维生素C、磷脂、葡萄糖氧化酶等重要营养成分含量的测定 ,发现这三种花粉的以上成分含量都很高。其中青木千花粉的维生素A含量达 70 641 .6IU/ 1 0 0g ,氨基酸总量达 2 4 .443mg/ 1 0 0mg。从营养的角度来看 ,青木千花粉是较优秀的花粉。     

土壤砷污染对蔬菜砷含量及食用安全性的影响

对湖南郴州砷污染区的土壤和蔬菜砷含量进行了研究 ,结果表明该地区土壤含砷量为 19.5～ 2 37.2 mg/ kg、平均为 6 3.9mg/ kg、中值为 4 7.8mg/ kg,比全国平均土壤含砷量 (9.2 m g/ kg)高 2～ 2 5倍 ;蔬菜可食部分砷含量范围为 0 .0 4～ 2 .6 4 m g/ kg、平均为 0 .74 mg/ kg、中值为 0 .5 4 mg/ kg,5 4 %的蔬菜可食部分含砷量超过了《蔬菜卫生标准》规定的最大允许量 (MPC≥ 0 .5mg/ kg) ;菠菜 ,茼蒿和生菜可食部分超标比较严重 ,最大砷含量超出 MPC 5倍左右。     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Entwicklungsgeschichte und Ultrastruktur von Pollenkitt und Exine bei nahe verwandten entomophilen und anemophilen Angiospermensippen derAlismataceae,Liliaceae, Juncaceae,Cyperaceae, Poaceae undAraceae

Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.

     

Identification and Characterization of the First Equine Parainfluenza Virus 5

正Dear Editor,Parainfluenza virus 5 (PIV5), known as canine parainfluenza virus in the veterinary field, is a negative-sense,nonsegmented, single-stranded RNA virus belonging to the Paramyxoviridae family (Chen 2018). The virus was first reported in primary monkey kidney cells in 1954 (Hsiung1972), then it has been frequently discovered in various     

Pathogenic Characterization and Full Length Genome Sequence of a Reassortant Infectious Bursal Disease Virus Newly Isolated in Pakistan

<正>Dear Editor,Infectious bursal disease (IBD) is one of the most important diseases of the poultry. The IBD virus (IBDV), a nonenveloped virus belonging to the Birnaviridae family with a genome consisting of two segments of double-stranded RNA (segments A and B), targets B lymphocytes of bursa of Fabricious leading to immunosuppression. In Pakistan,poultry farming is the second biggest industry and IBD is the second biggest disease threating the poultry sector.However, there is limited genome information of IBDV