查尔酮异构酶基因过表达对新疆雪莲类黄酮生物合成的调控

新疆雪莲（Saussurea involucrata Kar. et Kir.）是我国名贵中药材，其主要药用活性成分为黄酮类化合物。目前人们对新疆雪莲及它的黄酮类化合物的需求日益增多，但雪莲的人工栽培技术尚未成熟，在野生状态下，新疆雪莲只能生长在海拔4,000到5,000米的雪山上，现在由于过度采挖已濒临灭绝。为解决雪莲资源匮乏，提高雪莲中黄酮类成分的含量，本研究通过基因工程手段利用发根农杆菌将黄酮代谢途径中的关键酶－查尔酮异构酶（CHI）基因导入新疆雪莲，产生转基因新疆雪莲毛状根及再生苗，以期提高新疆雪莲的黄酮类物质含量，进行新疆雪莲黄酮类物质的生产。主要结果如下： 　　1．对克隆到的水母雪莲查尔酮异构酶基因（Smchi）进行功能分析。转Smchi正义、反义烟草的CHI酶活性实验结果表明，转Smchi正义的烟草CHI酶活性比对照提高3-6倍，而转反义Smchi基因的烟草CHI酶活性比对照则显著降低。分析不同株系的转基因烟草和对照烟草的黄酮含量和花色素含量表明，转Smchi正义的烟草积累比对照显著增高水平的总黄酮，其中株系CS-5黄酮含量是对照的6倍，转Smchi反义的烟草则积累较低水平的总黄酮，而且转基因烟草的总黄酮含量与Smchi基因的表达水平和CHI酶活性成正相关。但不论转Smchi基因正义或反义方向的烟草，其花色素含量和对照相比均没有发生显著变化。进一步对转基因烟草的黄酮成分进行分析，发现烟草中的主要黄酮成分芦丁在转Smchi正义烟草中有很高的积累。 　　2．发根农杆菌介导法将Smchi基因导入新疆雪莲，得到转Smchi基因的新疆雪莲毛状根。实验发现，35S-chi转基因对毛状根的生长没有显著影响，但35S-chi转基因毛状根能够合成显著提高水平的芹菜素和总黄酮，其中根系C46经过35 d培养，能产生32.1 mg/L的芹菜素和647.8 mg/L的总黄酮，分别是对照根系的12倍和4倍;不同根系的Smchi基因表达水平、CHI酶活性和芹菜素含量成正相关。本研究为通过基因工程手段提高新疆雪莲毛状根芹菜素和总黄酮含量提供了一个有效方法。 　　3．在1/2MS附加GA1.5 mg/L的培养基上，新疆雪莲毛状根的不定芽再生频率高且不定芽生长健壮。再生苗在MS+BA1.0 mg/L+NAA0.1 mg/L的培养基上继代培养生长量较大，经过20 d的培养，35S-chi转基因新疆雪莲再生苗株系（C17、C27、C46）、对照再生苗（Control-1）和正常试管苗（Control-2）之间生长量差异不显著，增殖倍数都在7倍左右;实验还发现，毛状根再生苗比各自来源的毛状根的芹菜素和总黄酮含量下降了20-30%，但转基因再生苗的芹菜素和总黄酮含量比Control-1和Control-2都有显著提高，其中C46芹菜素和总黄酮含量分别为1.86 mg/g 干重和37.3 mg/g干重，分别是Control-1的12倍和 2.4 倍，Control-2的4 倍和1.6倍。这些结果表明由毛状根诱导出的再生苗可作为增强目标次生代谢产物生产的另外一个有效来源。 　　

水稻(Oryza sativa L. ssp japonica)幼苗根质膜蛋白质组分析

根质膜具有重要的生物学功能，它参与了根响应脱落酸（ABA）的一系列活动。尽管已经有很多有关ABA影响根的生长和发育的报道，但是在蛋白质组水平上研究参与ABA信号转导及相关活动的质膜蛋白质的报道还未见到。我们期望利用蛋白质组学技术平台研究外源ABA胁迫下水稻根质膜与ABA功能相关的蛋白质组的变化。 本论文通过双向电泳（2DE）结合质谱（MALDI-TOF MS 和 MALDI-TOF/TOF MS）分析的方法鉴定了102个质膜相关蛋白质。这些蛋白质功能涉及到跨膜运输（16.2%）、胁迫反应（14.3%）、物质运输（4.8%）、细胞骨架动态变化（5.7%）、细胞壁重建（3.8%）、碳代谢和能量循环（13.3%）、蛋白质代谢（14.3%）、信号转导（18.1%）和其他功能的蛋白质（4.8%），以及未知功能的蛋白质（2.9%）。其中大约30％的蛋白质以同工型的形式存在。在这些鉴定结果中，有10个斑点（代表10种蛋白质）已被报道为质膜特异的蛋白质;68个蛋白质斑点（代表58种蛋白质）是质膜相关蛋白质。其余54个蛋白质斑点（代表42种蛋白质）是首次在水稻根的质膜囊泡中被鉴定出来。 在ABA处理条件下，我们在2DE胶上发现了15个响应ABA调节的蛋白质斑点。9个上调的蛋白质斑点分别代表以下9种蛋白质：vacuolar proton-ATPase A subunit, vacuolar ATPase B subunit、patatin、 Salt-stress root protein RS1、谷氨酰氨合成酶（Glutamine synthetase，GS）、OSR40c1、H+-exporting ATPase （vacuolar ATPase E subunit）、甘油醛-3-磷酸脱氢酶I型（glyceraldehyde-3- phosphate dehydrogenase, type I，GADPH）和醛缩酶C-1（aldolase C-1）。6个下调的蛋白质斑点分别代表4种蛋白质：endosperm lumenal binding protein、remorin protein、富含脯氨酸蛋白质（glycine-rich protein，GRP）和蔗糖合成酶（sucrose synthase, SuSy）。其中，OSR40c1和endosperm lumenal binding protein与蛋白质合成相关，从它们与ABA的关系中可以看出，ABA可能抑制了细胞的蛋白质合成。而vacuolar proton-ATPase A subunit、vacuolar ATPase B subunit和 H+-exporting ATPase参与了细胞质pH的调控，ABA致使了细胞质pH的上升。甘油醛-3-磷酸脱氢酶I型、醛缩酶C-1和蔗糖合酶参与了细胞壁的生长发育，ABA的作用可能导致了细胞壁生长发育的延迟。ABA促使Patatin上升，其作用可能与质膜膜脂的降解有关。而ABA的刺激也使谷氨酰氨合成酶的表达显著上升，谷氨酰氨合成酶可以去除细胞内有害的游离NH+4。同时还有未知功能的富含脯氨酸蛋白质（glycine-rich protein，GRP）同样受到ABA的诱导，但具体的功能及其与ABA的关系还要进一步的实验证据。

Intraspecific variation of isozymes in Arenicola marina (Polychaeta: Annelida)

Six enzyme systems, namely acid phosphatase, leucine aminopeptidase, phosphoglucose isomerase, tetrazolium oxidase, esterases and malate dehydrogenase were studied electrophoretically in Arenicola marina from various localities in United Kingdom. Out of 13 presumed loci, ten were found monomorphic. The three loci which appeared to be polymorphic are LAP-1, EST-2 and TO-1. Due to small sample size allele frequencies and genetic identity were not calculated. However, results indicate genetic difference among the population of A. marina.

甘油和蔗糖对光系统I结构与功能的影响

在光系统I(PSI)内部结合有大量的水分子，而这些水分子的生理功能还不清楚。在本工作中，我们通过外加具有渗透活性和吸水强的多羟基化合物甘油和蔗糖来改变PSI环境中水的含量，研究水的改变对PSI结构与功能的影响。主要结果如下： 1．甘油和蔗糖对PSI的电子传递产生影响，影响程度和大小与它们的浓度有关。一般地，低浓度的甘油和蔗糖可促进PSI的电子传递，而在高浓度时，这种促进作用有所减弱。但过高浓度的甘油(>60%, v/v)会抑制PSI的电子传递活性。 2．与对PSI电子传递的影响趋势相类似，在低浓度的甘油和蔗糖存在下，PSI的光化学反应活性(PSI反应中心色素P700的光氧化还原能力)大为增加，而较高浓度的甘油和蔗糖对P700的氧化还原能力有所抑制。 3．甘油和蔗糖也会改变PSI中的主体色素(bulk chlorophyll)和长波色素或红色素(red chlorophyll)之间的能量分布。它们的作用导致激发能分配失衡，使更多的激发能分配到红色素。 4．甘油和蔗糖的作用还会影响PSI的蛋白质构象。甘油使PSI蛋白质内部的色氨酸残基(Trpapolar)处于更加疏水的微环境，而蔗糖却使极性环境中的色氨酸残基(Trppolar)周围微环境的极性继续增大。它们均会使色氨酸残基邻近的具有淬灭活性的蛋白质的位置和/或方向有所变化。同时，甘油和蔗糖的作用也会导致PSI的疏水性增加。

葡萄浆果成熟与延迟采收期间糖酸变化特点的研究

连续2年对“京秀”ד亚历山大”（编号97-2）杂交后代10个单株和“京秀”ד香妃”（编号97-3）杂交后代10个单株成熟期和延迟采收期的糖酸组分含量进行测定，以了解葡萄浆果延迟采收内在品质的变化差异。第二年 对可长期挂果的亲本“京秀”、“亚历山大”和杂交后代单株“97-2-23”、“97-2-24”成熟期和延迟采收期糖酸组分动态变化进行测定，以了解葡萄浆果糖酸品质延迟采收期的动态变化规律。同时对以上四个单株的浆果中蔗糖代谢相关酶活性和浆果呼吸强度进行测定，以对不同蔗糖表现型的产生原因进行探讨。研究表明： 葡萄延迟采收，浆果内可溶性糖变化可分为积累型和稳定型两种类型。延迟采收3周，糖积累型的8个单株浆果 可溶性糖显著积累，而稳定型的12个单株的糖与成熟时不存在显著差异。浆果主要积累果糖和葡萄糖，这两种糖的 动态变化趋势基本一致，但果糖变化幅度较大。两种类型的有机酸含量在延迟采收期间变化不大，没有显著差异。 糖积累型的“京秀”和“97-2-23”延迟采收期间各蔗糖分解酶（酸性转化酶、中性转化酶、蔗糖合成酶分解方 向）活性持续升高，但糖稳定型的“亚历山大”和“97-2-24”延迟采收第3周时急剧降低。此外，果实成熟和延迟 采收期间两种糖表现型浆果的呼吸速率也存在差异。浆果的蔗糖分解酶活性和呼吸速率存在的差异可能是两种类型 延迟采收期间糖含量存在差异的重要原因。

Suitability of sodium lactate as cryoprotectant and its effect on gel forming ability and protein denaturation of croaker fish surimi during frozen storage

The effect of sodium lactate is compared with sucrose + sorbitol + sodium tri-poly phosphate as cryoprotectant on gel forming ability & protein denaturation of croaker surimi during frozen storage at -20±2°C for 90 days was evaluated. The quality of Croaker surimi with 6% (w/v) sodium lactate was examined in terms of biochemical parameters of muscle protein, thaw drip, gel strength and calcium ATPase activity :.omparing with those of surimi added with sucrose/sorbitol & without additive as control. Both the cryoprotectants minimized the negative effects of frozen storage on physico-chemical traits of myofibrillar proteins which was evident from the biochemical and sensory parameters. The residual Ca2+ ATPase activity and gel strength of surimi with sodium lactate were higher than those of control throughout 90 days of storage. Ca2+ A TPase activity and gel strength found a high positive correlation. From the results, it was found that sodium lactate was equally effective in preservation of croaker muscle protein native structure during frozen storage as the sucrose/ sorbitol and also less sweet without any risk of maillard browning.

基于磷酸丙糖异构酶基因序列的蓝氏贾第鞭毛虫分子系统发育的研究

[目的 ]探讨蓝氏贾第鞭毛虫种内系统发育及遗传多样性。 [方法 ]对不同来源虫株的磷酸丙糖异构酶(tim)基因进行 PCR扩增、序列测定后 ,用简约法和 NJ法构建分子系统树进行系统学分析。 [结果 ]在所测序列中共有 12 4个位点存在变异 (2 3% ) ,且大多数为发生在第三密码子的同义突变 ,两种构树方法所得两树的分枝结构相似 ,均将受试的 16株蓝氏贾第鞭毛虫分为明显的两组。 [结论 ]tim基因可作为研究蓝氏贾第鞭毛虫群体遗传结构一个有效的遗传标记

Denaturation of Labeo rohita (Rohu) actomyosin on frozen storage: preventive effect of carbohydrates

The preventive effect of sucrose and glucose on the denaturation of frozen rohu actomyosin at -20°C for 7 weeks was examined using an in vitro test model. The rate of denaturation was followed by estimating percentage salt extractability, Ca¹²+ ATPase activity and the clearing response test. Sucrose and glucose showed cryoprotective action for all concentration of actomyosin. Higher actomyosin concentration was preserved better than lower concentration. Post-rigor actomyosin was preserved to a greater extent than pre-rigor actomyosin. Correlation between percentage salt extractability and enzyme activity could not be observed in all samples of frozen actomyosin studied.

Improvement of diet attractability for Penaeus monodon by supplementing various attractants

An experiment was undertaken to test the effect of supplemental krill meal, earthworm meal, glycine, sucrose or mussel water on diet attractibility of Penaeus monodon. Only glycine or mussel water significantly improved diet attractibility

Survival and changes in the fine structure of selected tissues of Penaeus monodon Fabricius juveniles fed various carbohydrates

Penaeus monodon juveniles were reared on semipurified diets containing various carbohydrates (maltose, sucrose, dextrin, molasses, cassava starch, corn starch or sago palm starch). Significant differences were observed between the type as well as the level of carbohydrate in the diet on the survival of the juveniles. Results indicate that there does not seem to be any correlation between survival and the complexity of the carbohydrates.

Study on shelf life of fish cake prepared from surimi of silver carp (Hypophthalmichthys molitrix) during frozen storage

Surimi was prepared from silver carp with an aim to put this underutilized fish for profitable use. The mince prepared was washed twice with chilled water (5°C) using mince to water ratio (w/v) of 1:2 for 5-6 minutes each. After final dewatering to moisture content to about 80%; half the quantity of washed minced meat was mixed with cryoprotectants (4% sorbitol, 4% sucrose and 0.3% sodium tripolyphosphate) to produce surimi. The prepared surimi and the dewatered minced meat were packed in LDPE bags, frozen using a plate freezer and stored at -20°C. Surimi and dewatered minced meat from frozen storage were used as base material for production of fish cakes. These were fried at 160°C for 3 to 4 minutes before serving for organoleptic test. Changes in salt soluble nitrogen, total volatile base nitrogen, non-protein nitrogen, peroxide value and free fatty acid of surimi and dewatered mince were estimated at every ten days interval during the storage period of 3 months. The study has indicated that frozen storage of surimi could be a potential method for effective utilization of silver carp. This surimi when incorporated in fish cakes yielded products which retained the shelf life even up to 90 days of storage.

Meiothermus rosaceus sp nov isolated from Tengchong hot spring in Yunnan, China

A rosy-pigmented Gram-negative, thermophilic bacterium with an optimum growth temperature of about 55degreesC was isolated from Tengchong hot springs in Yunnan province, China. Its growth scarcely occurred below 40degreesC or above 70degreesC. Phylogenetic and secondary structural analyses of 16S rRNA and DNA-DNA hybridization showed that the organism represented a new species of the genus Meiothermus. This new species could be distinguished easily from other species of the genus Meiothermus by the following phenotypic characteristics: rosy pigment, expanded body, sucrose and maltose were not utilized, gelatin and starch were not hydrolyzed. On the basis of the above data, the name Meiothermus rosaceus sp. nov. was proposed for the species represented by the strain RH9901(T)(CCTCC-AB200291). (C) 2002 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.

Design guidelines for granular particles in a conical centrifugal filter

Essential design criteria for successful drying of granular particles in a conical continuous centrifugal filter are developed in a dimensionless fashion. Four criteria are considered: minimum flow thickness (to ensure sliding bulk flow rather than particulate flow), desaturation position, output dryness and basket failure. The criteria are based on idealised physical models of the machine operation and are written explicitly as functions of the basket size lout, spin velocity Ω and input flow rate of powder Qp. The separation of sucrose crystals from liquid molasses is taken as a case study and the successful regime of potential operating points (lout, Ω) is plotted for a wide range of selected values of flow rate Qp. Analytical expressions are given for minimum and maximum values of the three independent parameters (lout, Ω, Qp) as a function of the slurry and basket properties. The viable operating regime for a conical centrifugal filter is thereby obtained as a function of the slurry and basket properties. © 2012 The Institution of Chemical Engineers.

Enzyme-free glucose biosensor based on low density CNT forest grown directly on a Si/SiO2 substrate

A highly sensitive nonenzymatic amperometric glucose sensor was fabricated by using Ni nanoparticles homogeneously dispersed within and on the top of a vertically aligned CNT forest (CNT/Ni nanocomposite sensor), which was directly grown on a Si/SiO2 substrate. The surface morphology and elemental analysis were characterized using scanning electron microscopy and energy dispersive spectroscopy, respectively. Cyclic voltammetry and chronoamperometry were used to evaluate the catalytic activities of CNT/Ni electrode. The CNT/Ni nanocomposite sensor exhibited a great enhancement of anodic peak current after adding 5 mM glucose in alkaline solution. The sensor can also be applied to the quantification of glucose content with a linear range covering from 5 μM to 7 mM, a high sensitivity of 1433 μA mM-1 cm-2, and a low detection limit of 2 μM. The CNT/Ni nanocomposite sensor exhibits good reproducibility and long-term stability, moreover, it was also relatively insensitive to commonly interfering species, such as uric acid, ascorbic acid, acetaminophen, sucrose and d-fructose. © 2013 Elsevier B.V.

Outer membrane proteins induced by iron deficiency in Anabaena sp PCC 7120

Iron deficiency can induce cyanobacteria to synthesize siderophore receptor proteins on the outer membrane to enhance the uptake of iron. In this study, an outer membrane of high purity was prepared from Anabaena sp. PCC 7120 based on aqueous polymer two-phase partitioning and discontinuous sucrose density ultra-centrifugation, and the induction of outer membrane proteins by iron deficiency was investigated using 2-D gel electrophoresis. At least. five outer membrane proteins were newly synthesized or significantly up-regulated in cells transferred to iron-deficient conditions, which were all identified to be siderophore receptor proteins according to MALDI-TOF-MS analyses. Bacterial luciferase reporter genes luxAB were employed to monitor the transcription of the encoding genes. The genes were induced by iron deficiency at the transcriptional level in different responsive modes. Luciferase activity expressed from an iron-regulated promoter may be used as a bioreporter for utilizable iron in natural water samples. (C) 2009 National Natural Science Foundation of China and Chinese Academy of Sciences. Published by Elsevier Limited and Science in China Press. All rights reserved.