巴西橡胶树HbRPS6-2基因的克隆与生物信息学分析

从巴西橡胶树甲基化过滤文库中筛选到一个与RPS6同源性较高的基因片段,根据该基因片段序列信息,设计特异引物,利用RACE进行特异片段的5’和3’扩增,获得长度为1 327 bp的HbRPS6-2基因克隆。生物信息学分析表明,该基因包含483 bp的开放阅读框,5’非翻译区为357 bp,3’非翻译区为475 bp,编码161个氨基酸。在HbRPS6-2氨基酸序列中没有预测到信号肽和跨膜区,二级结构分析表明其属于混合型蛋白。HbRPS6-2在N端前18个氨基酸区域内有一个较强的疏水区,但整条多肽链表现为亲水性。对15个RPS6系统进化分析发现,巴西橡胶树的RPS6-2基因与多杀性巴氏杆菌的RPS6基因亲缘关系最近,而与拟南芥和玉米等亲缘关系相对较远。     

巴西橡胶树MADS-27基因的克隆与生物信息学分析

以巴西橡胶树花芽为材料，利用RT-PCR技术从总RNA中扩增获得1个MADS基因。cDNA长度1 063 bp，开放阅读框717 bp，编码239个氨基酸，命名为HbMADS-27。在HbMADS-27氨基酸序列中具有1个较强的跨膜区，二级结构分析结果表明其属于混合型蛋白。HbMADS-27在N端前34～50氨基酸区域内为较强的疏水区，但整条多肽链表现为亲水性。对20个MADS蛋白进行系统进化分析，结果发现，巴西橡胶树的HbMADS-27基因与蓖麻的MADS-27基因亲缘关系最近，而与拟南芥MADS-27基因亲缘关系相对较远。     

巴西橡胶树HbUBC14基因克隆、生物信息学及表达分析

从巴西橡胶树中鉴定出一个泛素结合酶(UBC)基因,该基因长653 bp,最长开放阅读框504 bp,预测编码蛋白包含167个氨基酸;序列比对分析发现,该基因编码的蛋白具有一段保守的UBC结构域,与拟南芥E2成员UBC14(At3g55380)具有较高的相似性,故将该基因命名为HbUBC14。半定量RT-PCR分析结果表明,HbUBC14在巴西橡胶树胶乳中表达最高,在花药中表达最低。与健康橡胶树相比,死皮树胶乳中HbUBC14表达量明显下降。HbUBC14表达还受乙烯和茉莉酸调控。以上结果表明,HbUBC1     

割手密过氧化物酶基因（SsPOD-1）cDNA克隆与功能分析

割手密（Saccharum spontaneum）属于甘蔗属细茎野生种,具有较强的抗逆性,是甘蔗育种的优良材料。过氧化物酶（POD）是活性氧系统（ROS）中的一个关键酶,是植物应对干旱胁迫的关键调控酶之一。利用同源克隆的方法,以割手密为材料,成功克隆2个POD等位基因序列（SsPOD-1a和SsPOD-1b,GenBank登录号为KJ002565和KJ002566）。经测序鉴定,这2个基因长度均为1 083 bp,其中包括27 bp的5′非编码区、60 bp的3′非编码区及一个996 bp的开放阅读框,共编码331个氨基酸,这2个等位基因的序列相似性为98.8％。蛋白质保守结构域分析结果表明,此2个基因均具有POD基因典型保守结构域,属于依赖于亚铁血红素Ⅲ型POD亚类。原核表达结果表明,这2个基因编码区能正常表达出目的蛋白,说明得到的这2个基因为功能基因,而不是假基因。POD基因分子系统分生分析结果表明,割手密POD基因与高粱、玉米、水稻等禾本科植物亲缘关系较近,与一些双子叶植物及裸子植物也有一定的亲缘关系,这也证实了POD基因起源较为古老且存在高度保守区。     

花生△12-脂肪酸脱氢酶基因的克隆及序列分析

根据已报道的△12-脂肪酸脱氢酶基因(FAD)的氨基酸保守序列设计引物进行RT-PCR扩增,得到花生△12-脂肪酸脱氢酶基因881bp部分cDNA序列,然后通过快速扩增cDNA末端技术(RACE),向两端延伸得到1410bp的花生△12-脂肪酸脱氢酶基因全长cDNA序列。序列分析表明有一个长1140bp、编码379个氨基酸残基的开放阅读框,所编码蛋白质的大小约为43kDa。推测的氨基酸序列具有膜整合蛋白酶特异性的3个组氨酸保守区;氨基酸疏水性分析结果表明,所编码的氨基酸序列存在2个具有膜固定蛋白(membrance-anchored protein)重要特征的疏水结构,2个疏水区共跨膜4次,这些特性表明所获得的序列为△12-脂肪酸脱氢酶基因。     

巴西橡胶树HbCXE1基因克隆及其生物信息学分析

采用PCR和RACE技术从巴西橡胶树无性系热研7-33-97的乳管细胞中克隆到一条CXE羧酸酯酶蛋白家族基因HbCXE1，该基因cDNA全长1272 bp，含有一个长951 bp的阅读框，编码含316个氨基酸的HbCXE1蛋白。生物信息学分析表明，HbCXE1蛋白理论分子量为35.5437 ku，理论等电点为5.94，HbCXE1蛋白与蓖麻、杨树、葡萄、苹果、拟南芥的CXE蛋白同源性分别为75.08%、62.81%、62.31%、59.43%、57.68%。HbCXE1蛋白具有羧酸酯酶蛋白家族的特征结构，     

巴西橡胶树叶绿体型果糖-1,6-二磷酸酶基因的全长cDNA克隆与表达分析

利用RACE技术从巴西橡胶树中克隆到一个叶绿体型FBPase基因,命名为HbcpFBPase。该基因的c DNA全长为1 512 bp,包含1 209 bp的开放阅读框,编码一个由402个氨基酸残基组成的蛋白,蛋白分子量大小约为43.88 ku,理论等电点为6.64。多重序列比对表明该基因为叶绿体型果糖-1,6-二磷酸酶。Target P软件预测HbcpFBPase在叶绿体中的概率是0.961。实时荧光定量PCR分析表明,HbcpFBPase基因在雌花中表达量最高,雄花及种子次之;此外,机械伤害和割胶以及多种植物激素如乙烯利ET及植物生长素2,4-D可使HbcpFBPase基因下调表达。研究结果对进一步研究橡胶树光合作用碳固定、以及深入研究光合作用与胶乳合成之间的关系提供理论参考。     

巴西橡胶树HbEBP1生物学特性、原核表达及氨肽酶活性分析

从巴西橡胶树中筛选到了Hb EBP1基因,该基因序列长度为1 462 bp,其中5′端非编码区长度为141 bp,3′端非编码区长度为133 bp,其c DNA序列具有完整的阅读框,编码395个氨基酸,推导的Hb EBP1分子量为43.596 ku,等电点位为6.45。生物信息学分析结果表明巴西橡胶树Hb EBP1具有3个保守结构域:增值相关蛋白2G4(PA2G4-like)、氨肽酶M24(APP_Met AP)、甲硫氨酸氨肽酶(MAP)结构域。对原核表达的Hb EBP1蛋白进行氨肽酶活性测定,发现体外表达的Hb EBP1蛋白没有Map活性。这些结果表明,橡胶树Hb EBP1基因并不存在氨肽酶活性。     

湘油15 PGIP9蛋白基因的克隆和蛋白序列结构分析及原核表达

运用生物信息学软件对湘油15 PGIP9基因的核苷酸、蛋白氨基酸序列进行分析,并对其蛋白结构进行预测.结果表明:湘油15 PGIP9编码区CDS长1011 bp,编码336个氨基酸的开放阅读框,分子量为37.5kDa,等电点为7.9.N端1～22个氨基酸是信号肽,且这一区域疏水性较强,具有5个潜在的N-糖基化位点.N端和C端还各具有4个参与二硫键形成的半胱氨酸残基.二级结构显示有11个α-螺旋,14个β-延伸和25个无规则卷曲.中心LRR结构域由6个串联的LRR基序组成.随后将PGIP9的CDS序列亚克隆到原核表达载体pET -32a(+)中,构建pET - 32a - PGIP9重组表达质粒,并转化E.coil BL21(DE3),25℃,终浓度为0.2 mmol/L和0.5 mmol/L的IPTG诱导2h,都成功的表达了融合蛋白pET - 32a - PGIP9,其分子量约为52kDa,发现主要以包涵体形式存在.没有可溶形式的蛋白表达.     

甘蓝型油菜固醇载体蛋白2基因BnSCP-2的克隆与表达

固醇载体蛋白2(SCP-2)是一类小分子碱性蛋白,参与细胞内脂质运输、脂肪酸代谢以及过氧化物酶体β-氧化等过程。利用同源序列设计引物进行PCR扩增,克隆得到甘蓝型油菜固醇载体蛋白2基因的c DNA序列,命名为BnSCP-2。BnSCP-2的开放阅读框长372bp,编码一个由123个氨基酸残基组成的蛋白质,预测的蛋白质相对分子质量为13.52kD,等电点为9.35。SCP-2蛋白氨基酸序列非常保守,系统进化分析表明BnSCP-2与拟南芥SCP-2同源性最高。荧光实时定量PCR结果表明BnSCP-2在检测的各个组织均有表达,其中花和花蕾中的表达量最高;赤霉素、细胞分裂素和脱落酸等可显著诱导幼苗中该基因的表达,推测该基因可能参与调控幼苗生长发育。     

Mineral composition of some traditional Mexican teas

Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.     

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.     

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.     

Redox Status and Neuro Inflammation Indexes in Cerebellum and Motor Cortex of Wistar Rats Supplemented with Natural Sources of Omega-3 Fatty Acids and Astaxanthin: Fish Oil,Krill Oil,and Algal Biomass

Health authorities worldwide have consistently recommended the regular consumption of marine fishes and seafood to preserve memory, sustain cognitive functions, and prevent neurodegenerative processes in humans. Shrimp, crabs, lobster, and salmon are of particular interest in the human diet due to their substantial provision of omega-3 fatty acids (n-3/PUFAs) and the antioxidant carotenoid astaxanthin (ASTA). However, the optimal ratio between these nutraceuticals in natural sources is apparently the key factor for maximum protection against most neuro-motor disorders. Therefore, we aimed here to investigate the effects of a long-term supplementation with (n-3)/PUFAs-rich fish oil, ASTA-rich algal biomass, the combination of them, or krill oil (a natural combination of both nutrients) on baseline redox balance and neuro-inflammation indexes in cerebellum and motor cortex of Wistar rats. Significant changes in redox metabolism were only observed upon ASTA supplementation, which reinforce its antioxidant properties with a putative mitochondrial-centered action in rat brain. Krill oil imposed mild astrocyte activation in motor cortex of Wistar rats, although no redox or inflammatory index was concomitantly altered. In summary, there is no experimental evidence that krill oil, fish oil, oralgal biomass (minor variation), drastically change the baseline oxidative conditions or the neuro-inflammatory scenario in neuromotor-associated rat brain regions.     

Potential of dry fractionation of wheat bran for the development of food ingredients,part II: Electrostatic separation of particles

Wheat bran is a composite material made of several layers, such as pericarp, testa and aleurone. It could be fractionated into purified fractions, which might either be used as food ingredients, or serve as a starting material for extraction of bioactive compounds. The aim of this work was to evaluate the potential of using electrostatic separation as a way to obtain purified fractions from wheat bran. Ultrafine-ground bran obtained either by cryogenic grinding or by grinding at ambient temperature was used as starting material. The ultrafine bran was then charged by tribo-electrification and introduced in a chamber containing two high voltage electrodes, where bran particles were separated depending on their acquired charge, allowing positively and negatively charged fractions to be collected separately. The particle size distribution, microstructure and biochemical composition of the obtained fractions were studied. The charge of the particles was influenced by their biochemical composition: particles rich in highly branched and cross-linked arabinoxylans (pericarp) were separated from particles rich in β-glucan, ferulic acid and para-coumaric acid (aleurone cell walls). The testa and the intracellular compounds from aleurone were not highly charged, neither positively nor negatively. The most positively charged fraction represented 34% of the initial bran, and contained 62% of the ferulic acid present in the initial bran. The yield of the separation process was good (5.4% loss), and could be further increased.     

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.     

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.     

<Emphasis Type="Italic">Pulque</Emphasis>, An Alcoholic Drink from Rural Mexico,Contains Phytase. Its <Emphasis Type="Italic">in vitro</Emphasis> Effects on Corn Tortilla

Pulque is made by fermenting the agave sap or aguamiel of Agave atrovirens with a whole array of microorganisms present in the environment including several lactic acid bacteria and yeasts such as Saccharomyces cerevisiae. Ascorbic acid was determined in pulque and aguamiel, respectively. Phytase activity in lees, liquid and freeze-dried pulque was assayed by measuring the appearance of phosphate from phytate by a colorimetric method likewise phosphate from phytate present in fresh corn tortilla was measured after in vitro incubation with pulque. Iron, zinc, calcium, magnesium and selenium contents were measured in pulque and corn tortilla as well as in nixtamalized corn flour (NCF), the latter is used to make instant tortilla, since corn provides most of the energy as well as most of the phytate in the Mexican rural diet. Pulque showed phytase activity but much less ascorbic acid and iron than previously reported; additionally, phytase in pulque hydrolyzed most of phytate’s corn tortilla. Lees, which is mostly made of pulque’s microbiota, significantly accumulated iron and zinc but no selenium. NCF was fortified with iron by the manufacturers but poorly blended. There were significant differences on selenium content between tortillas samples, apparently some soils in central Mexico are selenium deficient. Moderate pulque intake appears to increase the bioavailability of iron and zinc bound by phytate in corn.