王不留行环肽研究

从中药王不留行（Ｖａｃａｒｉａｓｅｇｅｔａｌｉｓ）种子中分离并鉴定了４个环肽化合物,分别命名为王不留行环肽Ａ,Ｂ,Ｃ,Ｄ（ｖａｃｃａｒｉｎｓＡ,Ｂ,Ｃ,Ｄ）,其中王不留行环肽Ａ为新环肽化合物。其结构通过光谱和化学方法分别确定为：ｖａｃｃａｒｉｎＡ——ｃｙｃｌｏ－（Ｔｒｐ－Ａｌａ１－Ｇｌｙ－Ｖａｌ－Ａｌａ２）,ｖａｃｃａｒｉｎＢ———ｃｙｃｌｏ－（Ｐｒｏ－Ｇｌｙ－Ｌｅｕ－Ｓｅｒ－Ｐｈｅ１－Ａｌａ－Ｐｈｅ２）,ｖａｃｃａｒｉｎＣ———ｃｙｃｌｏ－（Ｐｒｏ１－Ｇｌｙ－Ｔｙｒ－Ｖａｌ－Ｐｒｏ２－Ｌｅｕ－Ｔｒｐ）,ｖａｃａｒｉｎＤ———ｃｙｃｌｏ－（Ｐｒｏ－Ｖａｌ１－Ｔｒｐ－Ａｌａ－Ｇｌｙ－Ｖａｌ２）．     

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）。     

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     

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．     

结合于GATA元件的Ⅳ型锌指蛋白

至今已发现了四种锌指蛋白（Ｚｆｐ）。Ⅰ型为Ｃｙｓ－Ｘ２－４－Ｃｙｓ－Ｘ３－Ｐｈｅ－Ｘ５－Ｌｅｕ－Ｘ２－Ｈｉｓ－Ｘ３－Ｈｉｓ,简写Ｃ２Ｈ２。ＴＦⅢＡ为Ｃ２Ｈ２×９,即９个锌指的重复单位。Ｓｐ１为Ｃ２Ｈ２×３。目前已发现有１０００种以上具有Ⅰ型锌指同源保...     

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．     

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．     

湖北省吨粮田的现状及其投肥效率分析

湖北省吨粮田的现状及其投肥效率分析孙先（华中农业大学,武汉４３００７０）ＣｕｒｒｅｎｔＳｉｔｕａｔｉｏｎａｎｄＦｅｒｔｉｌｉｚａｔｉｏｎＥｆｆｉｃｉｅｎｃｙｏｆＨｉｇｈＰｒｏｄｕｃｔｉｖｅＣｒｏｐｌａｎｄｓｉｎＨｕｂｅｉＰｒｏｖｉｎｃｅ￥ＳｕｎＸｉａｎ－ｒｏｎｇ（ＣｅｎｔｒａｌＣｈｉｎａＡｇｒｉｃｕｌｔｕｒｅＵｎｉｖｅｒｓｉｔｙ,Ｗｕｈａｎ４３００７０）．ＣｈｉｎｅｓｅＪｏｕｒｎａｌｏｆＥｃｏｌｏｇｙｌ１９９３,１２（２）：５５－５６．Ｓｉｎｃｅ１９９０,ｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｈｉｇｈｐｒｏｄｕｃｔｉｖｅｃｒｏｐｌａｎｄｈａｓｂｅｅｎａｃｃｅｌｅｒａｔｅｄａｎｄｔｈｅｅｆｆｅｃｔｏｆｉｔｓｙｉｅｌｄａｎｄｂｅｎｅｆｉｔｉｎｃｒｅａｓｅｉｓｖｅｒｙｏｂｖｉｏｕｓ,Ｂｕｔ,ｗｈｅｔｈｅｒｈｉｇｈｙｉｅｌｄａｎｄｈｉｇｈｅｆｆｉｃｉｅｎｃｙｃａｎｂｅｓｙｎｃｈｒｏｎｉｚｅｄｄｅ－ｓｅｒｖｅｓｃｌｏｓｅａｔｔｅｎｔｉｏｎ,Ｉｎｔｈｉｓｒｅｓｅａｒｃｈ,７９ｈｉｇｈｙｉｅｌｄｃｒｏｐｐｉｎｇｐａｔｔｅｒｎｓａｒｅｉｎｖｅｓｔｉｇａｔｅｄｆｏｒｔｈｒｅｅｙｅａｒｓｉｎＨｕｂｅｉａｎｄｔｈｅｉｒｅｆｆｉｃｉｅｎ     

农业系统生产力（ASP）的量化及其现状分析

农业系统生产力（ＡＳＰ）的量化及其现状分析卢进登,韩纯儒（北京农业大学农学系,１０００９４）ＱｕａｎｔｉｆｉｃａｔｉｏｎｏｆＡｇｒｏｓｙｓｔｅｍＰｒｏｄｕｃｔｉｖｉｔｙ（ＡＳＰ）ａｎｄＡｎａｌｙｓｉｓｏｎｉｔｓＣｕｒｒｅｎｔＳｉｔｕａｔｉｏｎｉｎＣｂｉｎａ￥．ＬｕＪｉｎ－ｄｅｎｇ;ＨａｎＣｈｕｎｒｕ（ＢｅｉｊｉｎｇＡｇｒｉｃｕｌｔｕｒａｌＵｎｉｖｅｒｓｉｔｙｆＢｅｉｊｉｎｇ１０００９４）．ＣｈｉｎｅｓｅＪｏｕｒｎａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（２）：２１－２２．ＢａｓｅｄｏｎａｂｒｉｅｆａｎａｌｙｓｉｓｏｎｔｈｅｆｏｒｍａｔｉｏｎｐｒｏｃｅｓｓｏｆＡＳＰ,ｉｔｓｃｏｎｃｅｐｔｉｓｄｅｓｃｒｉｂｅｄａｎｄａｎｉｎｔｅｇｒａｔｅｄｉｎｄｉ－ｃａｔｏｒｆｏｒｉｔｓｑｕａｎｔｉｆｉｃａｔｉｏｎ—ＡＳＰ２ｉｓｐｕｔｆｏｒｗａｒｄｓ．Ｆｒｏｍｔｈｏｓｅ,ｔｈｅＡＳＰｌｅｖｅｌｓｉｎｖａｒｉｏｕｓｒｅｇｉｏｎｓｏｆＣｈｉｎａａｒｅａｎａｌｙｚｅｄａｎｄ８ｌｅｖｅｌｓａｒｅｄｉｖｉｄｅｄｂｙｕｓｉｎｇ．Ｈｉｅｒａｒｃｈｉｃｃｌｕｓｔｅｒｉｎｇｍｅｔｈｏｄ．Ｉｔ’ｓ：ｃｌａｒｉｆｉｅｄｔｈａｔＡＳ－ＰＩｉｓａｍｏｒｅ     

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.     

鸡传染性法氏囊病病毒研究进展

传染性法氏囊病(Infection bursal disease, IBD)是由鸡传染性法氏囊病毒(Infectious bursal disease virus, IBDV)引起的鸡和火鸡的一种高度接触性传染病,给世界各国的禽养殖业带来了巨大损失.自IBDV发现至今新的变异株不断出现,分子结构的改变导致病毒致病力的改变及宿主对疫苗应答的改变,使得传统的疫苗已不能控制其流行,因此各国学者对其基因组结构和功能进行了广泛深入的研究,并积极研制新型有效的疫苗以达到防治的目的.     

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).