瓦草中三个新环肽

从云南民间中草药瓦草（Ｓｉｌｅｎｅｓｚｅｃｈｕｅｎｓｉｓ）的根中分离鉴定了３个新的环肽,分别命名为瓦草环肽Ａ,Ｂ,Ｃ（ｓｉｌｅｎｉｎｓＡ,Ｂ,Ｃ）用光谱和化学方法确定它们均为环八肽,其结构分别为：ｓｉｌｅｎｉａＡ－ｃｙｃｌｏ－（Ｐｒｏ－Ｌｅｕ－Ｓｅｒ－Ｐｈｅ－Ｐｒｏ－Ｔｙｒ－Ｌｅｕ－Ｖａｌ）,ｓｉｌｅｎｉｎＢ－－ｃｙｃｌｏ－（Ｐｈｅ－Ｌｅｕ－Ａｌａ－Ｐｒｏ－Ｌｅｕ－Ｐｒｏ－Ｐｈｅ－Ｐｒｏ）,ｓｉｌ     

金铁锁根中的环肽成分

从云南民间重要的药用植物金铁锁（Ｐｓａｍｍｏｓｉｌｅｎｅ ｔｕｎｉｃｏｉｄｅｓ Ｗ．Ｃ．Ｗｕ ｅｔ Ｃ．Ｙ．Ｗｕ）的根中分离得到２个新的天然环二肽以及２个新的环八肽：金铁锁环肽Ａ和Ｂ（ｐｓａｍｍｏｓｉｌｅｎｉｎｓ Ａ ａｎｄ Ｂ）。它们的结构经光谱方法鉴定为ｃｙｃｌｏ（－Ａｌａ－Ａｌａ－）,ｃｙｃｌｏ（－Ｖａｌ－Ａｌａ－）,ｃｙｃｌｏ（－Ｐｒｏ１－Ｐｈｅ１－Ｐｒｏ２－Ｐｈｅ２－Ｐｈｅ３－Ａｌａ－ｐ     

千针万线草环肽A的结构修正

从云南民间药物千针万线草（Ｓｔｅｌｌａｒｉａ ｙｕｎｎａｎｅｎｓｉｓ）的根中分离到一新环肽ｓｔｅｌｌａｒｉｎＡ。前报主要利用快速原子轰击质谱确定其结构为ｃｙｃｌｏ（Ｇｌｙ－Ｐｒｏ－Ｐｈｅ－Ｔｙｒ－Ｇｌｙ－Ｇｌｙ－Ｐｒｏ）。最近利用最新二维核磁结合快速原子轰击质谱及酶降解重新考察了其结构,修正为ｃｙｃｌｏ（Ｇｌｙ－Ｐｒｏ－Ｐｈｅ－Ｐｒｏ－Ｇｌｙ－Ｔｙｒ－Ｇｌｙ）。     

3个六肽的胰岛素受体结合和体内生物活性

为了研究胰岛素受体结合部位的结构和功能,设计并用固相方法合成了３个六肽．在浓度大于１×１０３ｎｍｏｌ／Ｌ时,ｃｙｃｌｏ（Ｐｈｅ－Ｐｈｅ－Ｖａｌ－Ｌｅｕ－Ｔｙｒ－Ｇｌｙ）具有明显的胰岛素受体结合活力;Ｈ－Ｐｈｅ－Ｐｈｅ－Ｖａｌ－Ｌｅｕ－Ｔｙｒ－Ｇｌｙ－ＯＨ的这一活力则不明显;而Ｈ－Ｇｌｙ－Ｇｌｕ－Ａｒｇ－Ｇｌｙ－Ｐｈｅ－Ｐｈｅ－ＯＨ则增强胰岛素和其受体的亲和性．然而,它们都没有体内生物活性．这表明：环六肽部分模拟了胰岛素受体结合部位的空间构象;胰岛素受体结合部位的疏水性和其中的Ｂ２３Ｇｌｙ－Ｂ２４Ｐｈｅ－Ｂ２５Ｐｈｅ对胰岛素和其受体的结合起重要作用．     

凤眼莲根分泌物氨基酸组分对根际肠杆菌属F_2细菌的趋化作用

凤眼莲（Ｅｉｃｈｈｏｒｎｉａｃｒａｓｓｉｐｅｓ）的根分泌物中含有Ｍｅｔ等多种氨基酸,其中Ｍｅｔ、ＧＡＢＡ、Ｇｌｙ、Ａｌａ、Ａｓｐ、Ｓｅｒ、Ｖａｌ和Ｌｅｕ（１０－７～１０－２ｍｏｌ·Ｌ－１）均对凤眼莲的根际肠杆菌属Ｆ２（Ｅｎｔｅｒｏｂａｃｔｅｒｓｐ．Ｆ２）细菌有强烈的正趋化作用;Ｇｌｕ、Ｔｈｒ和Ｈｉｓ（１０－７～１０－３ｍｏｌ·Ｌ－１）也对该菌有一定的正趋化作用;而Ｌｙｓ、Ｃｙｓ、Ａｒｇ、Ｔｙｒ、Ｐｒｏ、Ａｓｎ、Ｇｌｎ、Ｉｌｅ、Ｐｈｅ和Ｔｙｐ则对该菌表现出一定的负趋化作用．对细菌的正趋化作用存在一个趋化物的最适浓度范围．具有正趋化作用的氨基酸在凤眼莲根际的浓度都较高,而具有负趋化作用的浓度则较低,这正是凤眼莲与该根际细菌结合为根际微生态系统的原因之一．     

Na2CO3胁迫对星星草幼苗游离氨基酸含量的影响

对Ｎａ２ＣＯ３胁迫下星星草幼苗游离氨基酸含量的研究结果表明,星星草幼苗游离氨基酸总含量随盐浓度的增加而增加。各组分中Ａｌａ、Ｃｙｓ、Ｇｌｙ、ｌｅｕ、Ｍｅｔ、Ｐｒｏ、Ｐｈｅ、Ｖａｌ的含量随着Ｎａ２ＣＯ３浓度的增加而增加,其中Ａｌａ、Ｃｙｓ、Ｇｌｙ、ｌｅｕ、Ｍｅｔ、Ｐｒｏ与Ｎａ２ＣＯ３浓度呈极显正相关关系。Ｎａ２ＣＯ３胁迫下星星草幼苗体内氨累积,同时Ａｓｐ－ＮＨ２的含量明显增加,有效降低氨对幼苗的毒     

从织锦芋螺中克隆α芋螺毒素序列

为了从我国南海产织锦芋螺（Ｃｏｎｕｓｔｅｘｔｉｌｅ）中分离新的毒素序列并研究其应用价值,进行了织锦芋螺毒素基因的分离工作．从织锦芋螺毒管中提取ｍＲＮＡ,以Ａ族芋螺毒素的信号肽编码部分和３′端非翻译部分的保守序列为引物,通过ＲＴ－ＰＣＲ扩增和序列分析方法获得新的芋螺毒素序列．结果得到两种不同的α芋螺毒素序列,两者都属于α４／７亚型芋螺毒素,预测其成熟肽序列分别为Ｐｒｏ－Ｇｌｕ－Ｃｙｓ－Ｃｙｓ－Ｓｅｒ－Ａｓｐ－Ｐｒｏ－Ａｒｇ－Ｃｙｓ－Ａｓｎ－Ｓｅｒ－Ｓｅｒ－Ｈｉｓ－Ｐｒｏ－Ｇｌｕ－Ｌｅｕ－Ｃｙｓ－Ｇｌｙ（Ｃ端Ｇｌｙ可能被酰胺化）和Ｐｒｏ－Ｇｌｕ－Ｃｙｓ－Ｃｙｓ－Ｓｅｒ－Ｈｉｓ－Ｐｒｏ－Ａｌａ－Ｃｙｓ－Ａｓｎ－Ｖａｌ－Ａｓｐ－Ｈｉｓ－Ｐｒｏ－Ｇｌｕ－Ｉｌｅ－Ｃｙｓ－Ａｒｇ．采用传统的生化分离手段尚未从织锦芋螺中获得过α芋螺毒素序列,这两种α芋螺毒素作用的种属特异性、受体类型特异性和在小细胞肺癌的诊断和治疗中的应用价值有待进一步研究     

肾小球疾病儿童体内游离氨基酸含量的研究

为了研究小儿肾小球病变时体内游离氨基酸的代谢变化,采用丹酰氯聚酰胺薄层分析法研究了原发性肾病综合症（ＩＮＳ）８例、急性肾小球肾炎（ＡＧＮ）１２例、过敏性紫癜肾炎（ＡＰＮ）７例与正常对照组２９例的血清及红细胞内游离氨基酸含量的变化。结果表明：（１）此三种肾小球疾病,血清中苯丙氨酸（Ｐｈｅ）、脯氨酸（Ｐｒｏ）、色氨酸（Ｔａｐ）、赖氨酸（Ｌｙｓ）、甘氨酸（Ｇｌｙ）明显高于正常,导致酪／苯丙（Ｔｙｒ／Ｐｈｅ）、缬／甘（Ｖａｌ／Ｇｌｙ）等分子比降低,提示肾功能受损。（２）血清支链氨基酸（ＢＣＡＡ）的含量在ＩＮＳ中低于正常组（ｔ＝３．４８;Ｐ＜０．０１）,而在ＡＧＮ、ＡＰＮ中却高于正常组（ｔ分别为２．３３,２．３９,Ｐ＜０．０５）。（３）红细胞中丝氨酸（Ｓｒｅ）、苯丙氨酸（Ｐｈｅ）、色氨酸（Ｔｒｐ）、胱氨酸＋半胱氨酸（Ｃｙｓ）、天冬氨酸（Ａｓｐ）、谷氨酸（Ｇｌｕ）的含量ＡＰＮ组高于ＩＮＳ及ＡＧＮ,提示ＡＰＮ患儿中肾功能损害没有ＩＮＳ及ＡＧＮ严重。     

蛇毒蛋白Echistatin的C端突变基因的构建,表达及其活性研究

通过ＰＣＲ定点突变的技术,将蛇毒蛋白Ｅｃｈｉｓｔａｔｉｎ基因的Ｃ端进行了突变（Ａｌａ４８→Ａｒｇ４８→,Ｔｈｒ４９→Ｖａｌ４９）,模拟纤维蛋白Ｎ端的四肽（Ｇｌｙ－Ｐｒｏ－Ａｒｇ－Ｖａｌ）,以期增加Ｅｃｓ（Ｅｃｈｉｓｔａｔｉｎ）的活性,突变的基因重组到表达质粒ｐＪＣ２６４上,经ＩＰＴＧ诱导,以ＣｈｅＹ－Ｅｃｓ融合蛋白方式进行了表达,表达量占菌体总蛋白的１５￣２０％,Ｓｅｐｈａｄｅｘ Ｇ－７５初步纯化     

蜈蚣碱性蛋白SSmp-d的分离纯化及其部分理化性质的鉴定

少棘巨蜈蚣（ＳｃｏｌｏｐｅｎｄｒａｓｕｂｓｐｉｎｉｐｅｓｍｕｔｉｌａｎｓＬ．Ｋｏｃｈ）经９５％乙醇脱脂后,再经４℃水冷渗,水提液低温旋转浓缩,冻干,得到的冻干粉先后经过ＳｅｐｈａｄｅｘＧ－２５柱,等电聚焦制备电泳,再经ＳｅｐｈａｄｅｘＧ－１５０柱,ＳｅｐｈａｄｅｘＧ－１００柱,最后经ＨＰＬＣ制备得到一个纯的碱性蛋白,命名为ＳＳｍｐ－ｄ．该蛋白经ＨＰＬＣ、超薄等电聚焦电泳检验是均一的．采用ＨＰＬＣ和Ｐｒｏｔｅｉｎ－ＰａｋＴＭ１２５柱测定其分子量为２４．６４ｋＤ．ＩＥＦ－ＨＰＣＥ显示其等电点为９．２７．氨基酸分析表明ＳＳｍｐ－ｄ含较多的Ａｒｇ、Ｌｙｓ等碱性氨基酸,另外还含有较多的Ａｌａ、Ｌｅｕ．使用蛋白质自动序列分析仪测定了ＳＳｍｐ－ｄＮ端的１１个氨基酸,序列为ＮＨ３＋－Ａｓｐ－Ｖａｌ－Ａｓｎ－Ｐｈｅ－Ａｒｇ－Ｌｅｕ－Ｓｅｒ－Ｇｌｙ－Ａｌａ－Ａｓｐ－Ｐｒｏ．     

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     

Similar aerosol emission rates and viral loads in upper respiratory tracts for COVID-19 patients with Delta and Omicron variant infection

Highlights
1 Aerosol emission rates of Delta or Omicron patients were similar.
2 Viral loads in upper respiratory tract of Alpha, Delta and Omicron patients were similar.
3 Viral loads in upper respiratory tract of vaccinated or unvaccinated Delta patients had no difference.     

Recombinant human interferon-α1b inhibits SARS-CoV-2 better than interferon-α2b in vitro

Highlights
1) A comprehensive evaluation method for anti-SARS-CoV-2 drugs was established based on RT-qPCR, TCID₅₀ method, and immunofluorescence.
2) A significant antiviral effect of rHuIFN-α1b was shown with EC₅₀=0.12 IU/mL in Vero cells and EC₅₀=0.52 IU/mL in Calu-3 cells, which was better than rHuIFN-α2b (EC₅₀=0.25 IU/mL in Vero cells and EC₅₀=2.48 IU/mL in Calu-3 cells).
3) rHuIFN-α1b has a good potential in the application of anti-COVID-19 therapy.