Synthesis of (R)-2-trimethylsilyl-2-hydroxyl-propionitrile catalyzed by (R)-hydroxynitrile lyase from Prunus japonica seed meal

Synthesis of (R)-2-trimethylsilyl-2-hydroxyl-propionitrile via asymmetric transcyanation of acetyltrimethylsilane with acetone cyanohydrin in an aqueous/organic biphasic system catalyzed by (R)-hydroxynitrile lyase from Prunus japonica seed meal was successfully carried out for the first time. The optimal volume ratio of aqueous to organic phase, buffer pH value and reaction temperature were 15% (v/v), 5.0 and 30°C, respectively, under which both substrate conversion and product enantiomeric excess (ee) were 99%. Silicon atom in the substrate showed great effect on the reaction. Acetyltrimethylsilane was a much better substrate for (R)-hydroxynitrile lyase from Prunus japonica than its carbon analogue.     

Characterization of microsatellite loci from the Japanese eel Anguilla japonica

The Japenese eel, Anguilla japonica, is generally assumed to be composed of a single population with wide distribution range, and some genetic studies using allozyme or mitochondrial DNA methods supported this population model. However, one genetic study suggested the existence of multiple populations in this species, and thus, more detailed studies on the population structure is needed. Here we characterized a total of 11 microsatellite markers of the Japanese eel. These will serve as powerful tools for detailed population study for the Japanese eel, though two of them showed the significant departure from the Hardy–Weinberg expectations.     

Combined effects of experimental heavy-metal contamination (Cu, Zn, and CH3Hg) and starvation on quail’s body condition

Combined effects of heavy-metal contamination (Cu, Zn, and CH₃Hg) and starvation were tested on common quails (Coturnix coturnix japonica) and used as a model for comparison with a wild common guillemot (Uria aalge) population found stranded at the Belgian coast. Appropriate heavy-metal levels were given to the quails to obtain concentrations similar to those found in the seabirds’s tissues. The contaminated animals were then starved for 4 d to simulate the evident malnutrition symptoms observed at the guillemot’s level. In such conditions, food intake and total-body weight are shown to decrease in contaminated individuals with simultaneous significant hepatic and renal increase of the heavy-metal concentrations. Like guillemots, higher heavy-metal levels were observed in those contaminated quails that had also developed a cachectic status characterized by a general atrophy of their pectoral muscle and complete absence of subcutaneous and/or abdominal fat depots. Although likely the result of a general protein catabolism during starvation, it is suggested that these higher metal levels could as well enhance a general muscle wasting process (cachectic status).     

5份粳型亲籼种质的生物学特性及育种利用

本研究以5份自主选育的粳型亲籼种质明恢413、明恢1616、明恢1707、明恢512和明恢509为研究材料,通过对其生物学特性和育种利用进行研究和评价,以期为今后开展粳型亲籼种质资源的选育和籼粳亚种间杂种优势的利用提供理论参考.生物学特性研究结果表明:5份粳型亲籼种质的播始历期偏长,株高适中,直立穗型,穗子小,着粒密,...     

中华绒螯蟹卵巢差减cDNA文库的构建

应用抑制性差减杂交技术构建中华绒螯蟹卵巢两个发育时期的差减cDNA文库。正向差减杂交以Ⅲ期卵巢为试验方、Ⅱ期卵巢为驱动方,反向差减杂交以Ⅱ期卵巢为试验方、Ⅲ期卵巢为驱动方;将所获差减cDNA片段克隆入质粒表达载体,转化大肠杆菌JM109。最后获得的正、反向差减文库分别含863、360个重组子。PCR扩增鉴定正、反向差减cDNA文库的插入片段平均大小分别为360和160bp,表明所构建的差减言语库适合进一步研究中华绒螯蟹卵巢发育相关基因。     

青荚叶〔Helwingia japonica(Thunb.)Dietr.〕种下新组合

青荚叶〔Ｈｅｌｗｉｎｇｉａｊａｐｏｎｉｃａ (Ｔｈｕｎｂ .)Ｄｉｅｔｒ.〕为山茱萸科(Ｃｏｒｎａｃｅａｅ)青荚叶属 (ＨｅｌｗｉｎｇｉａＷｉｌｌｄ .)植物 ,我国民间常将其髓部、叶及果实作为药用。该种主要特征为叶片纸质 ,卵形、卵圆形、长卵形或卵状披针形 ,背面粉白或淡绿色等[1 ] 。作者在对馆藏的青荚叶标本进行整理时 ,发现《中国植物志》中的个别变种描述与该变种原始文献的描述有出入 ,而且该种种内的一些分类依据不明确。为此作者查阅了有关标本及文献 ,对该种的这些问题进行了分析和讨论。青荚叶Ｈｅｌｗｉｎｇｉａｊａｐｏｎ…     

粳稻和籼稻D1蛋白光抑制敏感性的差异与其编码基因序列结构特征的相关性分析(英文)

粳稻 (OryzasativaL .ssp .japonica)和籼稻 (O .sativassp .indica)对光抑制的敏感程度存在差异 ,它们的叶绿体光反应中心Ⅱ核心蛋白D1的稳定性不同。以菌落原位杂交法克隆了粳稻“95 16”和籼稻“籼优 6 3”叶绿体D1蛋白的编码基因psbA。核苷酸序列同源比较显示 :两者在启动子区和 5′_UTR完全相同 ;编码区存在着个别碱基的差异 ,但均位于三联体密码的第三位 ,不影响氨基酸编码特性 ,在蛋白质氨基酸序列上没有差异 ;在 3′_UTR内存在寡聚U长度的差异。因此 ,粳稻和籼稻D1蛋白对光抑制作用敏感性的差异与其蛋白质的氨基酸序列结构无关 ,可能与调控psbA基因表达的上游因子或光保护机制的差异有关。     

Why is Aucuba japonica Smaller in Heavy Snowfall Areas? A Growth Simulation of Evergreen Broad-leaved Shrubs based on Shoot Allometry, Critical Shoot Sizes for Flowering and Photosynthetic Production

Aucuba japonica , an evergreen broad-leaved shrub. The model is based on the allometry of plant organs and incorporates the processes of flowering, branching, and allocation of biomass among different organs. Growth of model plants was simulated under different values of annual gross production per leaf area (LGP) for 15 years. The tree form was mainly determined by the critical shoot size for initiating flowering (SF), but the average increase of new shoot mass (INM) for two successive years had marked effects on the growth pattern of A. japonica in addition to SF. Under small LGP conditions, plants with larger SF did not flower or postponed the initiation of flowering. With increasing LGP, plants with larger SF had a greater advantage because of their high efficiency for vertical growth. A smaller SF was observed in A. japonica var. borealis, which is distributed in heavy snowfall areas, and resulted in precocious flowering with a higher reproductive rate. The small plant size and shoot size of var. borealis may be the result of selection for preventing the delay of the year in which reproduction starts under smaller LGP conditions. On the other hand, the large SF of A. japonica var. japonica, which is distributed in light snowfall areas, suppresses flowering under small LGP conditions, and flowering occurs only after achieving a certain amount of vertical growth. Received 8 July 1999/ Accepted in revised form 21 December 2000     

Isolation of Lectins by Affinity Chromatography with Porcine Plasma Proteins Immobilized on Agarose

To develop a convenient method to isolate lectins, we prepared an affinity gel by coupling plasma proteins with agarose beads under conditions where the pH did not exceed 7.5. The validity of the use of this affinity gel in combination with elution using a hapten saccharide was confirmed by isolation of concanavalin A from Jack bean meal. Successful application of the method was demonstrated by isolation of two novel vegetable lectins from udo (Aralia cordate) and wasabi (Wasabia japonica). The method would be useful to isolate new lectins from various sources including plant and animal tissues.     

A New Acylated Anthocyanin from the Red Flowers of Camellia hongkongensis and Characterization of Anthocyanins in the Section Camellia Species

Twelve anthocyanins (1-12) were isolated from the red flowers of Camellia hongkongensis Seem. by chromatography using open columns. Their structures were elucidated on the basis of spectroscopic analyses, that is, proton-nuclear magnetic resonance, carbon 13-nuclear magnetic resonance, heteronuclear multiple quantum correlation, heteronuclear multiple bond correlation, high resolution electrospray ionization mass and ultraviolet visible spectroscopies. Out of these anthocyanins, a novel acylated anthocyanin, cyanidin 3-O-(6-O-(Z)-p-coumaroyl)-β-galactopyranoside (6), two known acylated anthocyanins, cyanidin 3-O-(6-O-(E)-p-coumaroyl)-β-galactopyranoside (7) and cyanidin 3-O-(6-O-(E)-caffeoyl)-β-galactopyranoside (8), and three known delphinidin glycosides (10-12) were for the first time isolated from the genus Camellia. Furthermore, pigment components in C. japonica L., C. chekiangoleosa Hu and C. semiserrata Chi were studied.The results indicated that the distribution of anthocyanins was differed among these species. Delphinidin glycoside was only detected in the flowers of C. hongkongensis, which is a special and important species in the section Camellia. Based on the characterization of anthocyanins in the section Camellia species, there is a close relationship among these species,and C. hongkongensis might be an important parent for creating new cultivars with bluish flower color.