抗旱性不同的小麦幼苗对水分和NaCl胁迫的反应

分别测定抗旱小麦的８１３９（Ｔｒｉｔｉｃｕｍ ａｅｓｔｉｖｕｍ Ｌ．ｃｖ．８１３９）和干旱敏感品种甘麦８号（Ｔ．ａｅｓｔｉｖｕｍ Ｌ．ｃｖ．Ｇａｎｍａｉ Ｎｏ．８）在２０％ＰＥＧ６０００和１．２％ＮａＣｌ胁迫下的生长、光合作用、蒸腾作用及抗氧化保护系统的变化。结果表明,抗旱小麦８１３９对ＰＥＧ６０００有较强的抗性,但对ＮａＣｌ胁迫的抗性较差。ＮａＣｌ胁迫下,两种小麦根的生长均受到严重抑制,而在ＰＥ     

水分胁迫下山黧豆多胺代谢与β—N—草酰—L—α,β—二氨基丙酸？…

为了研究水分胁迫下山黧豆（Ｌａｔｈｙｒｕｓ ｓａｔｉｖｕｓ Ｌ．）叶片中多胺代谢与β－Ｎ－草酰－Ｌ－α,β－二氨基丙酸（ＯＤＡＰ）积累的相关关系,利用聚乙二醇（ＰＥＧ）对山黧豆幼苗进行水分胁迫处理,同时加入腐胺（Ｐｕｔ）,α－二氟甲基精氨酸（ＤＦＭＡ）和Ｐｕｔ＋ＤＦＭＡ。实验结果表明,随ＰＥＧ处理时间的延长,山黧豆幼苗叶片中Ｐｕｔ、亚精胺（Ｓｐｄ）和精胺（Ｓｐｍ）含量逐渐增加,特别是Ｓｐｍ含量增加     

小麦谷氨酸脱羧酶的纯化及部分性质研究

谷氨酸脱羧酶（ｇｌｕｔａｍａｔｅｄｅｃａｒｂｏｘｙｌａｓｅ,ＧＡＤ,ＥＣ４．１．１．１５）催化谷氨酸脱羧生成γ－氨基丁酸（γ－ａｍｉｎｏｂｕｔｙｒａｔｅ,ＢＡ）,植物中已从南瓜［１］、马铃薯和林生山黧豆［２］纯化了ＧＡＤ．ＧＡＤ活性在禾本科作物中作为...     

林生山黧豆谷氨酸脱羧酶的分离纯化及部分性质的研究

以林生山黧豆为材料,利用硫酸铵分段盐析,丙酮沉淀,ＤＥＡＥ－ＳｅｐｈａｒｏｓｅＦＦ离子交换柱层析,ＳｅｐｈａｃｒｙｌＳ３００凝胶过滤柱层析及ＦＰＬ－ＭｏｎｏＱ柱层析技术,以聚酰胺薄膜层析荧光定量法为酶活力检测手段,分离纯化了谷氨酰羧酶,达到电泳银染纯,纯化后的林生山黧豆谷氨酸脱羧酶活力达３７５．０９Ｕ．ｍｇ＾－１,纯化保数３８．２倍,经ＳＤＳ－ＰＡＧＥ测定,其亚基分子量为７０ｋＤ,经工ＰＡＧＥ确定     

盐分和水分胁迫盐地碱蓬幼苗渗透调节效应的研究

利用不同浓度ＮａＣｌ和等渗ＰＥＧ处理４ｄ龄的盐地碱蓬（Ｓｕａｃｄａ ｓａｌｓａ（Ｌ．）Ｐａｌｌ．）幼苗,１０ｄ后测定植株中主要有机溶质和无机离子的含量及叶片涌透势和涌透调节能力。结果表明,ＮａＣｌ处理的无机离子总含量急剧增加,其中Ｎａ＾２＋、Ｃｌ＾－半加最多,占总计算渗透势（ＣＯＰ）的７１％￣８８％,总无机离子占ＣＯＰ的９５％￣９７％。而有机溶质总含量则稍有降低,约上ＣＯＰ的２％￣５％。ＰＥＧ处理     

广西狸尾豆属一新种

广西狸尾豆属一新种沙文兰（广西天然药物研究中心,南宁５３００２２）关键词广西狸尾豆ＡＮＥＷＳＰＥＣＩＥＳＯＦＵＲＡＲＩＡＦＲＯＭＧＵＡＮＧＸｌ￥ｓｈａＷｅｎｌａｎ（ＧｕａｎｇｘｉＲｅｓｅａｒｃｈＣｅｎｔｒｅｏｆＮａｔｕｒａｌＭａｔｅｒｉａＭｅｄｉｃａ...     

广西狸尾豆属一新种

广西狸尾豆属一新种沙文兰（广西天然药物研究中心,南宁５３００２２）关键词广西狸尾豆ＡＮＥＷＳＰＥＣＩＥＳＯＦＵＲＡＲＩＡＦＲＯＭＧＵＡＮＧＸｌ￥ｓｈａＷｅｎｌａｎ（ＧｕａｎｇｘｉＲｅｓｅａｒｃｈＣｅｎｔｒｅｏｆＮａｔｕｒａｌＭａｔｅｒｉａＭｅｄｉｃａ...     

钙对水稻幼苗抗冷性的影响

ＣａＣｌ２浸种提高水稻幼苗叶片中结合态钙、内源抗氧化剂（ＧＳＨ、ＡｓＡ）含量和膜保护酶（ＣＡＴ、ＳＯＤ和ＰＯＤ）活性,也增加可溶性蛋白质中煮沸稳定蛋白质（ｂｏｉｌｉｎｇ－ｓｔａｂｌｅｐｒｏｔｅｉｎ）的含量。冷胁迫期间,ＣａＣｌ２并能减少因冷胁迫引起的ＧＳＨ、ＡｓＡ含量,ＣＡＴ、ＳＯＤ和ＰＯＤ活性以及煮沸稳定蛋白质下降的程度。在恢复期间,经ＣａＣｌ２处理的幼苗其ＧＳＨ、ＡＳＡ、ＣＡＴ、ＳＯＤ和ＰＯＤ以及煮沸稳定蛋白质水平均有回升。     

大田生长的林生山黧豆体内游离氨基酸含量

林生山黧豆（Lathyrussylvestris）是一种耐干旱抗贫瘠的多年生草本植物，含有丰富的游离氨基酸，特别是含有一些非蛋白质游离氨基酸，如2，4-二氨基丁酸，γ-氨基丁酸和高丝氨酸。国外文献报道的均是各种逆境条件下生长的林生山黧豆，本文则是大田生长的林生山黧豆，种子从美国引进。数年的栽培试验，表明它能适应我国北方气候。但其体内游离氨基酸的组成特点如何，尚不清楚。为此我们采用本实验室建立的聚酰胺薄膜层析荧光定量法，结合氨基酸自动分析仪，测定了其体内的游离特殊非蛋白质氨基酸和常规氨基酸。样品采自中国农业大学科学园…     

盐分和水分胁迫对盐地碱蓬幼苗渗透调节效应的研究

利用不同浓度ＮａＣｌ和等渗ＰＥＧ处理４０ｄ龄的盐地碱蓬（Ｓｕａｅｄａｓａｌｓａ（Ｌ．）Ｐａｌ．）幼苗,１０ｄ后测定植株中主要有机溶质和无机离子的含量及叶片渗透势和渗透调节能力。结果表明,ＮａＣｌ处理的无机离子总含量急剧增加,其中Ｎａ＋、Ｃｌ－增加最多,占总计算渗透势（ＣＯＰ）的７１％～８８％,总无机离子占ＣＯＰ的９５％～９７％。而有机溶质总含量则稍有降低,约占ＣＯＰ的２％～５％。ＰＥＧ处理使有机溶质（氨基酸、糖、有机酸）含量明显增加,特别是氨基酸占ＣＯＰ的９％。不同处理的实测渗透势（ＭＯＰ）均小于ＣＯＰ,说明在这些条件下,还有其它的渗透剂参与盐地碱蓬幼苗的渗透调节。结果还表明,盐地碱蓬幼苗的渗透调节能力随外界盐浓度的增大而增加。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

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     

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.     

Synthesis and antimicrobial studies of hydrazone derivatives of 4-[3-(2,4-difluorophenyl)-4-formyl-1H-pyrazol-1-yl]benzoic acid and 4-[3-(3,4-difluorophenyl)-4-formyl-1H-pyrazol-1-yl]benzoic acid

Microbial resistance to antibiotics is an unresolved global concern, which needs urgent and coordinated action. One of the guidelines of the Centers for Disease Control and Preventions (CDC) to combat antibiotic resistance is the development of new antibiotics to treat drug-resistant bacteria. In our effort to find new antibiotics, we report the synthesis and antimicrobial studies of 30 new pyrazole derivatives. These novel molecules have been synthesized by using readily available starting materials and benign reaction conditions. Some of these molecules have shown activity with MIC values as low as 0.78?µg/mL against four bacterial strains; Staphylococcus aureus, methicillin-resistant S. aureus, Bacillus subtilis, and Acinetobacter baumannii. Furthermore, active molecules are non-toxic to mammalian cell line.

     

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.     

Novel compounds with potent CDK9 inhibitory activity for the treatment of myeloma

Cyclin-dependent kinases (CDKs) and Polo-like kinases (PLKs) play key role in the regulation of the cell cycle. The aim of our study was originally the further development of our recently discovered polo-like kinase 1 (PLK1) inhibitors. A series of new 2,4-disubstituted pyrimidine derivatives were synthesized around the original hit, but their PLK1 inhibitory activity was very poor. However the novel compounds showed nanomolar CDK9 inhibitory activity and very good antiproliferative effect on multiple myeloma cell lines (RPMI-8226).