Two New Saponins from Lysimachia capillipes Hemsl.

To investigate the saponins from whole plants of Lysimachia capillipes Hemsl., two new saponins, named capilliposide E (1) and capilliposide F (2), were isolated. The structures of the new sa ponins were elucidated as 3 β, 22α-dihydroxy- 16α-acetat-28→ 13 -lactone-oleanane-3 -O- [β-D-glucopyranosyl(1→2)-α-L-arabinpyranoyl]-22-O-β-D-glucopyranoside (1) and 3 β, 22α-dihydroxy- 16α-acetat-28→ 13-1actone-oleanane-3-O- { [β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)]-α-L-arabinpyranoyl }-22-O-βD-glucopyranoside (2). The structures of these compounds were determined by 1D- and 2D-NMR, MS techniques, and chemical methods.     

Characterization and catabolic genes analyses of oil-degrading Pseudomonas aeruginosa 1217

One oil-degrading bacterial strain 1217 isolated from oil contaminated soil could degrade crude oil. It was identified and designated as Pseudomonas aeruginosa by morphology, physiology, biochemical and 16S rDNA sequence analyses. The strain grew well at 5-65 ℃ with the initial pH of 2-10 and NaCl concentrations of 0%-9%. It grew well in the medium containing different organic substrates as sole carbon sources, such as n-dodecane, n-octadecane, benzene, toluene, xylene and naphthaline. The degrading rates for hydrocarbons were 21.57% and 15.15% when it was cultured in minimal medium containing crude oil and different chain alkanes at 30 ℃ and 10 ℃ for 7 days. The bacterium produced biosurfactants with the surface tension reduction from 72.20 mN/m to 35.14 mN/m. The oil degrading related genes such as alkane monooxygenase, toluene dioxygenase, biphenyl dioxygenase, ring hydroxylating dioxygenase and oxidoreductase genes were detected in Pseudomonas aeruginosa 1217. The alkane monooxygenase and ring hydroxylating dioxygenase genes were further cloned and analyzed. The sequence similarities of the two genes with those of Pseudomonas aeruginosa PAO1 were 99.91% and 99.22% respectively. The isolated strain exhibits great potential for the bioremediation of the hydrocarbons contaminated environments.     

Study on intracellular trafficking of Mac-1 by direct visualization

Mac-1 (macrophage differentiation antigen asso-ciated with complement three receptor function), alsonamed CD11b/CD18, an adhesion molecule belongingresting leukocytes and at the surface of activated leu-kocytes (macrophages and neutrophils). Mac-1 playsan important role in the migration, chemotaxis and 2 Methodsphagocytosis of leukocytes[1]. Although there have 2.1 Observation of PMA-stimulated Mac-1 traffick-been several reports on the role of Mac-1 in neutrophil ingadh…     

狐源犬瘟热病毒H基因和F基因的克隆与序列分析

根据GenBank发表的犬瘟热病毒(CDV)核酸序列[CDV5804(AY386315)、CDV01-2689(AY649446)、CDV A75-17(AF164967)、CDV 00-2601(AY443350)、CDV 98-2645(AY445077)、CDV 98-2654(AY466011)和CDV Onderstepoort (AF378705)],分别设计合成扩增CDV H基因和F基因的引物.采用RT-PCR技术扩增狐源CDV泰安株(CDV-FOX-TA)H基因和F基因,分别将H基因与F基因克隆进这pMD18-T载体,进行序列分析.结果表明,CDV-FOX-TA株H基因有1个ORF,全长1 842bp,编码607个氨基酸,与CDV Onderstpoort、CDV Convac的同源性分别为89.2%和90.6%,与CDV LP的同源性为98.7%.CDV-FOX-TA F基因有1个ORF,全长1 889bp,编码662个氨基酸,CDV F蛋白信号肽区域易发生突变,但F0蛋白裂解点(RRQRR)、13个半胱氨酸残基、4个潜在的天冬氨酰糖基化位点和2个疏水区都高度保守.CDV H基因和F基因系统发生分析表明,CDV-FOX-TA与CDV A75-17和CDV LP亲源关系较为密切.     

DNA鉴定技术在法科学中的应用

人类基因组遗传多态现象研究的深入,导致了法科学领域个体识别和亲权鉴定发生根本性变化。本文就新的遗传标记和各种DNA鉴定技术在法科学中的研究进展、应用前景与亟待解决的问题进行了探讨。 Abstract：With the study advances on DNA polymorphism of human genome,radical changes have been taking place in forensic individual identification and paternity tests.In this paper,we introduced research progress of new genetic markers,their applications and problems should be solved urgently in the field of DNA-based identity test in forensic sciences.     

抗生素对大豆愈伤组织的诱导和生长的影响

用红霉素、头孢唑啉钠、头孢拉定、头孢霉素(国产和进口)等5种抗生素对农杆菌LBA4404进行抑菌试验,以头孢霉素的抑菌效果最好.头孢霉素作为抑菌剂用于大豆遗传转化试验时,在下胚轴浓度以300mg/L,在子叶节以500mg/L为宜.大豆品种对卡那霉素的反应在出愈率上表现相似,在褐化率上表现有些不同.大豆不同外植体对卡那霉素的反应存在较大差异,以真叶反应最敏感,下胚轴反应最迟钝.在以卡那霉素作为抗性选择标记时,选择压力真叶和子叶节以50～100mg,L为好,下胚轴以100～200mg/L为宜。 Ahstract:The experiment of inhibiting Agrobacterium LBA4404 was undertaken with 5 antibiotics (the Erythronycin Base,Cefazolin Sodium,Cefradine,2 kinds of Cefotaximes).Among them,Cefotaxime showed the best effect.When Cefotaxime is used in transformation,the ideal concentration is 300mg/L in hypocotyl and 500mg/L in cotyledon node.The response of soybean varieties to Kanamycin is similar in induction of callus rate and is different in brown rate of callus.Differences of the response of soybean explants to Kanamycin were found.The young leaves are sensitive to Kanamycin,but hypoeotyl is not.The ideal selecting pressure of Kanamycin is 50- l00mg/L in young leaf and cotyledon node,andl00-200mg/L in hypocotyl when Kanamycin is used as selection marker.     

空间和猎物密度对异色瓢虫取食柑橘木虱的影响

【目的】捕食功能与捕食行为发生的空间及猎物密度存在相关性,通过对异色瓢虫Harmoniaaxyridis (Pallas)在室内不同空间大小和柑橘木虱Diaphorina citri密度不同条件下的影响程度研究,可以为田间应用提供参考。【方法】分别设计不同的捕猎空间,研究捕食量和空间大小的相关性,采用高、低密度梯度下研究异色瓢虫对柑橘木虱的取食功能反应,以及在捕食笼中设置不同的猎物密度,统计日捕食头数。【结果】空间大小(x)与日捕食量(y)呈线性负相关,结果拟合y=﹣28.375x+130.08线性方程,不同密度梯度设置得到的HollingⅡ型功能反应曲线参数显示,高密度下异色瓢虫捕食柑橘木虱更快、更容易,异色瓢虫在不同柑橘木虱密度下持续捕食结果表明,起始密度高低影响第一天的捕食量,对随后的日捕食量影响不大。【结论】空间尺寸和猎物密度明显影响异色瓢虫成虫对柑橘木虱的捕食行为。     

Small RNAs in pollen

In plants, each pollen mother cell undergoes two rounds of cell divisions to form a mature pollen grain, which contains a vegetative cell(VC) and two sperm cells(SC). As a companion cell, the VC carries the SCs to an ovule by germinating a pollen tube. In-depth sequencing analyses of mature pollen showed that micro RNAs(mi RNAs) and short interfering RNAs(si RNAs) are present in both the VC and SCs. Additionally, epigenetically-regulated transposable elements(TEs) are reactivated in the VC and these TE m RNAs are further processed into 21-nt epigenetically reactivated si RNA(easiR NA) in SCs, which prevent 24-nt si RNA accumulation and sequester mi RNA loading. Small RNAs are thought to move from the VC to SCs, where they regulate gene expression and reinforce TE silencing. Here, we summarize current knowledge of the biogenesis and function of mi RNAs, si RNAs, and easi RNAs in pollen, emphasizing how these different small RNAs coordinately contribute to sperm cell formation and TE silencing.     

HIV/AID Research in China： Chasing against Time

The spread of HIV in China has lasted for over 20 years,and is marked by three periods:sporadic period(1984-1988),localized epidemic period(1989-1994),