木薯MADS-box基因克隆及其响应乙烯信号的表达模式分析

利用电子克隆技术从木薯基因组DNA中获得1个MADS-box基因，对其理化性质进行分析，并对该蛋白响应激素信号进行研究。结果表明：该基因含有全长为687 bp的ORF，编码229个氨基酸。通过对该蛋白进行ProtScale程序预测表明，该蛋白可能为亲水性蛋白；理化性质分析表明，该蛋白相对分子量为26.103 7 ku，等电点为6.87；跨膜结构域预测表明，该蛋白为非分泌型蛋白；亚细胞定位分析该蛋白可能定位于细胞核；磷酸化位点分析表明该蛋白能被丝氨酸激酶所磷酸化。运用定量PCR对该基因响应乙烯信号的表达模式进行分析，结果表明，该基因能够响应乙烯信号，并在外施乙烯12 h时具有最高的表达量。本研究为进一步研究该基因响应乙烯信号影响木薯叶片的生长发育提供研究基础。     

茶树OSCA基因家族的鉴定及表达分析

钙通透性阳离子通道蛋白（OSCA）在植物调节高渗胁迫中发挥着重要作用。为了解OSCA基因家族在茶树响应干旱胁迫中的作用,本研究基于茶树全基因组数据对OSCA基因家族进行鉴定,分析CsOSCAs基因和蛋白结构以及启动子顺式作用元件,并对CsOSCAs在茶树不同组织、不同抗旱性品种间和干旱胁迫下的表达模式进行分析。结果表明：茶树基因组包含12个OSCA基因家族成员,分别命名为CsOSCA1～CsOSCA12;CsOSCAs基因编码的氨基酸序列长度为667～831 bp,蛋白分子量在76 630.55～93 563.99 kDa之间,等电点在6.15～9.33之间,含有9～12个跨膜结构域,均含有特征保守结构域DUF221,根据系统进化关系可以分为4个亚族;10个CsOSCAs基因定位于茶树7条染色体上,2个CsOSCAs基因定位于未锚定染色体的contig上;CsOSCAs基因编码的蛋白二级结构含有32%～38%的跨膜结构和60%～68%的α-螺旋;CsOSCAs基因具有组织表达特异性,CsOSCA2、CsOSCA3、CsOSCA11、CsOSCA12基因在干旱敏感的品种CN98中的表达量...     

玉米弯孢叶斑病菌NADPH氧化酶生物信息学分析和ATMT敲除载体的构建

从JGI数据库玉米弯孢叶斑病菌(Curvularia lunata)基因组中获得2个编码NADPH氧化酶基因ClNox1和ClNox2。采用生物信息学方法对2个基因编码的蛋白质进行性质、结构和功能等方面的预测。结果表明,ClNox1和ClNox2的分子量分别为6.35和6.41 KD,等电点PI为8.87和8.93,不稳定指数为44.50和39.45;ClNox1是亲水性膜蛋白,包含6个明显的跨膜结构域;ClNox2也是膜蛋白,包含8个明显的跨膜结构域。在亚细胞水平上,ClNox1定位于线粒体上,而ClNox2定位于细胞质膜上;在氨基酸序列方面,ClNox1和ClNox2都含有多个苏氨酸、丝氨酸和酪氨酸激酶磷酸化位点;在功能方面,ClNox1和ClNox2都包含NADPH氧化酶特征结构域,并且与Cochliobolus heterostrophus的NADPH氧化酶基因具有较高的同源性。根据ClNox1和ClNox2序列设计特异性引物扩增目的片段,与标记基因NPTII和HphGFP分别连入骨架载体pPZP100,构建完成ClNox1和ClNox2基因的敲除载体pPZP100NPTIIClNox1和pPZP100HphGFPClNox2,为根癌农杆菌介导的遗传转化提供基础材料。     

玉米肉桂醇脱氢酶基因ZmCAD4的克隆和生物信息学分析

肉桂醇脱氢酶(CAD)是木质素生物合成途径的限速酶。对玉米B73基因组数据库和NCBI数据库中注释为玉米B73 CAD的基因进行挖掘和筛选,对其中1条玉米肉桂醇脱氢酶基因ZmCAD4克隆,并进行生物信息学分析。结果表明,共筛选到12条玉米CAD基因,克隆的ZmCAD4基因编码区全长1 104 bp,编码367个氨基酸。ZmCAD4蛋白含有典型的CAD1结构域、Zn结合位点和NADP结合位点,不含有跨膜结构域和信号肽,为非分泌蛋白,亚细胞定位预测定位在细胞质中。蛋白三级结构预测与拟南芥AtCAD5蛋白相似,相似度达到73.80%。系统进化分析表明,ZmCAD4与芒草、高粱等禾本科植物亲缘关系最近。     

青天葵甲羟戊酸激酶基因的编码蛋白预测和表达分析

甲羟戊酸途径(mevalonic acid, MVA)是植物三萜类化合物生物合成的主要途径，而甲羟戊酸激酶(mevalonate kinase, MVK)是MVA途径中的关键限速酶之一。根据前期获得的青天葵[Nervilia fordii(Hance)Schltr.]转录组数据，采用生物信息学方法对青天葵MVK基因编码蛋白的理化特性、功能结构域、二级结构、信号肽、跨膜结构域等进行预测，并采用RPKM法分析该基因在青天葵球茎和叶片的表达量。结果表明，NfMVK基因编码含有383个氨基酸的稳定型亲水性、酸性蛋白质，与其他植物MVK蛋白同源性可达70％。NfMVK蛋白分子量为41.29 ku，含有甲羟戊酸激酶功能域，归属于GHMP_Kinase超级家族。该蛋白没有任何信号肽、转运肽和跨膜结构域，二级结构为混合型结构的蛋白质。NfMVK基因在青天葵中的表达趋势为：球茎>叶片。该结果可为后续利用MVK基因调控青天葵三萜类活性成分的合成提供理论依据。     

电子克隆获取甜菜富亮氨酸类受体蛋白激酶基因BvLRR-RPK2;1完整编码区

针对前期获得的甜菜分子标记位点进行分析,以获得甜菜中该位点相关的基因。结合电子克隆与常规克隆,获取并验证目的基因片段,最后预测基因产物结构与功能。结果获得了一段长3467bp的片段,其中包含一个长3141bp的完整编码区,编码一个长1046aa的富亮氨酸类受体蛋白激酶。将基因命名为BvLRR-RPK2;1。基因编码区在基因组中连续存在,无内含子区域。基因翻译产物BvLRR-RPK2;1具有一个跨膜结构域,具有LRR-RPK家族的特征性结构域,与已知的LRR-RPK/RLK类蛋白序列相似性在85%以下,与甜菜本身的预测序列在编码区内部有5个碱基、2个氨基酸的差异。本文获得了一个甜菜中未经克隆的LRR-RPK2编码区,并预测了其产物功能。     

巴西橡胶树FERONIA类受体激酶基因(HbFER)的克隆及表达分析

植物受体类激酶在植物的生长发育和抗逆等生理过程中起着重要作用。在橡胶树转录组测序的基础上,通过RACE技术和RT-PCR方法,扩增得到橡胶树的一个类受体激酶基因的全长,命名为HbFER。该片段包含1个2 679 bp的开放阅读框,可编码892个氨基酸。生物信息学分析结果表明:该氨基酸序列与拟南芥、番茄、甘蓝和杨树的FER蛋白高度同源,其同源性分别为74.5%、74.7%、73.4%、82.9%。HbFER蛋白除了含有Malectin_like和PTKc结构域外,还含有1个信号肽(含22个氨基酸)和2个跨膜结构域。半定量分析结果表明,HbFER基因在不同组织中的表达水平存在差异,叶片和花中的表达丰度最高,胶乳中的表达丰度最低,且该基因在叶片中的表达受植物激素水杨酸的诱导。     

大豆GmABCG40基因的功能预测及表达分析

通过在大豆基因组数据库中检索拟南芥At ABCG40在大豆中的同源基因,获得了Gm ABCG40基因序列。通过对Gm ABCG40基因编码的氨基酸序列及启动子序列进行生物信息学分析,结果表明:Gm ABCG40基因CDS序列全长4 284 bp,编码1 427个氨基酸。Gm ABCG40编码的蛋白为疏水性蛋白,具有多个N-糖基化位点、激酶磷酸化位点、N-豆蔻酰化位点、2个ATP/GTP结合位点基序A和1个速激肽家族信号。结构域分析表明Gm ABCG40含有2个核苷酸结合域与2个跨膜结构域,形成NBD1-TMD1-NBD2-TMD2结构,属于ABCG亚家族的成员。Gm ABCG40预测的启动子区域含有与激素、胁迫、光应答、胚乳表达和转录因子结合相关的顺式作用元件。系统进化分析表明Gm ABCG40与菜豆、红豆、木豆、百脉根等豆科植物亲缘关系较近。组织特异性表达分析结果显示Gm DABCG40在叶片中表达量最低,在根中表达量最高,推测其可能参与根中ABA的转运过程。     

利用生物信息学方法鉴定和分析禾谷炭疽菌Rab蛋白家族

Rab蛋白作为分子开关,调控着丝状真菌中囊泡运输的各个过程。为明确禾谷炭疽菌(Colletotrichum graminicola)中Rab蛋白家族成员的数量和理化特征,本研究利用生物信息学的方法对禾谷炭疽菌中的Rab蛋白进行比对搜索,并对得到的Rab蛋白进行理化性质和系统进化分析,以期望为进一步阐明其功能提供理论指导。结果表明,禾谷炭疽菌中共有10个Rab蛋白候选基因,都编码小分子的亲水蛋白,编码产物都定位于胞内具有膜结构的细胞器上,其中有一半为稳定蛋白。此外,该Rab蛋白家族的绝大多数成员在丝状真菌中的进化是保守的,都具有保守的结构域,但是该家族个别成员与同属的黄瓜炭疽菌(Colletotrichum orbiculare)中的同源蛋白的进化距离较远,暗示了禾谷炭疽菌为了适应环境和更好地侵染植物进化出了可能具有特异性功能的Rab蛋白。本研究的结果将为深入明确Rab蛋白家族的具体功能奠定基础,期望为进一步设计更加合理有效的玉米炭疽病防治策略提供新思路。     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

Novel food and non-food uses for sorghum and millets

Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.     

In vitro antimicrobial activity of different accessions ofSolanum commersonii Dun. from Uruguay

Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.     

Extreme resistance to infection by potato virus X in genotypes of wild tuber-bearingSolanum species

Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X¹ (also called RX_act).     

Cyanobacteria Secondary Metabolites as Biotechnological Ingredients in Natural Anti-Aging Cosmetics: Potential to Overcome Hyperpigmentation,Loss of Skin Density and UV Radiation-Deleterious Effects

The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O₂^•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O₂^•− scavenging, (IC₅₀ = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC₂₅ = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC₅₀ = 863 µg/mL; elastase, IC₅₀ = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O₂^•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.     

Marine Pharmacology in 2009–2011: Marine Compounds with Antibacterial,Antidiabetic, Antifungal,Anti-Inflammatory,Antiprotozoal, Antituberculosis,and Antiviral Activities; Affecting the Immune and Nervous Systems,and other Miscellaneous Mechanisms of Action ?

The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.     

Recent Modifications of Chitosan for Adsorption Applications: A Critical and Systematic Review

Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules contributes to many possible adsorption interactions between chitosan and pollutants (dyes, metals, ions, phenols, pharmaceuticals/drugs, pesticides, herbicides, etc.). These functional groups can help in establishing positions for modification. Based on the learning from previously published works in literature, researchers have achieved a modification of chitosan with a number of different functional groups. This work summarizes the published works of the last three years (2012–2014) regarding the modification reactions of chitosans (grafting, cross-linking, etc.) and their application to adsorption of different environmental pollutants (in liquid-phase).