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1.
青稞OMT1基因克隆及原核表达分析 总被引：1，自引：0，他引：1
《核农学报》2017,(12)
类黄酮O-甲基转移酶(FOMT)是一种在植物甲基化黄酮代谢合成中有着重要作用的酶,但在中国青藏高原的特色作物青稞中研究较少。为了更好了解该酶及编码基因在青稞中的生理功能及作用,以高总黄酮青稞品系94-19-1为材料,通过RT-PCR扩增、克隆得到青稞OMT1基因的ORF序列。结果表明,该基因ORF长1 071 bp,编码356个氨基酸,预测蛋白分子量为38.65 KDa,等电点为5.33。序列比对分析发现,所克隆的基因与NCBI数据库收录的大麦Hv OMT1基因有99.44%的一致性,氨基酸序列存在5个残基差异,编码的蛋白序列具有OMT蛋白家族典型的保守结构域。进一步将该基因连接到原核表达载体转化大肠杆菌,最终成功将该基因所编码的蛋白在大肠杆菌诱导表达,并利用亲和层析柱分离技术,将该表达蛋白进行了纯化。这为进一步研究该酶蛋白功能和选育高品质青稞品种奠定了基础。 相似文献
2.
以伪狂犬病病毒GB株细胞培养物为模板，用PCR方法扩增蛋白激酶(PK)基因，对其进行了克隆、序列测定，并与PRV NIA-3株、Ka株和其他α-疱疹病毒进行了同源性比较。结果显示：所扩增的PK基因片段长1396bp，该片段包含一个开放阅读框(ORF)，长1005bp，编码由334个氨基酸组成的蛋白质。与NIA-3株及Ka株的核苷酸同源性为98．4％和97．5％，基因编码区氨基酸序列的同源性为98．2%和96．4％。具有真核细胞丝氨酸／苏氨酸蛋白激酶氨基酸亚结构域特征序列，而且α-疱疹病毒PK基因具有一些特征性的、共有的氨基酸序列。为今后研究PK基因的功能和构建PK缺失株奠定了基础。 相似文献
3.
查尔酮合成酶（chalcone synthase,CHS）是类黄酮生物合成的关键酶,在植物发育、防止UV损伤、抗病和逆境反应中起着重要作用。本研究通过EST测序,获得了罗汉果查尔酮合成酶基因序列（登录号：GU980155）。为了进一步了解罗汉果查尔酮合成酶基因的特征,我们将其与46种植物的查尔酮合成酶基因的核酸序列和氨基酸序列进行比对和进化分析。结果表明,罗汉果查尔酮合成酶基因的核酸序列和氨基酸序列与其它物种的查尔酮合成酶基因均具较高同源性,编码区相似性约为94%。使用PHYLIP和MEGA4分别构建了邻接树、最大似然树和最大简约树,但经bootstrap检验,最优树未能明确罗汉果查尔酮合成酶基因的系统发育地位。以紫花苜蓿查尔酮合成酶的三维结构为参考,利用同源建模的方法预测了罗汉果查尔酮合成酶的三维结构,发现罗汉果查尔酮合成酶具有保守的活性位点和空间结构。 相似文献
4.
甜高粱蔗糖合成酶基因（Susy2）的克隆及结构和功能分析 总被引：1，自引：0，他引：1
本研究以甘蔗蔗糖合成酶基因(susy2)cDNA序列为探针,对高粱EST数据库进行同源检索,将获得的4条与甘蔗相似性很高的EST序列进行拼接,后经基因组PCR、分子克隆和序列分析验证获得了甜高粱(sorghum bicofor)蔗糖合成酶基因DNA序列(Susy2,GenBank登录号为FJ513325).该序列全长4587 bp,起始密码子至终止密码子序列长4350 bp,包含一个2409 bp的开放读码框.该序列包含15个外显子和14个内含子,剪接方式都为GU/AG模式.Susy2编码的蛋白由802个氨基酸组成,分子量大小为91.7 kD,等电点pI为6.15.保守结构域分析表明,此蛋白含有一个475个氨基酸的GTI糖基化酶保守结构域(275～759),有4个ADP结合位点,能催化6-磷酸果糖和UDPG形成6-磷酸蔗糖. 相似文献
5.
FR—008聚酮合成酶基因的DNA序列分析 总被引：1，自引：0，他引：1
多烯类抗生素ＦＲ－００８基因簇中邻近于ｐａｂＡＢ基因的３．８ｋｂ片段的ＤＮＡ序列分析显示出３８０１ｂｐ的ＤＮＡ上存在着一个较大的不完整的２６７１ｂｐＯＲＦ，由这一ＯＲＦ推导出的蛋白质与Ｉ型聚酮合成酶及Ｉ型脂肪酸合成酶具有较强的同源性；推导出的蛋白氨基酸序列与夹竹桃霉素、红霉素聚酮合成酶中的β－酮合成酶及乙酰转移酶结构域中的保守氨基酸的排列非常一致。这一结果表明，３．８ｋｂ片段中不完整的ＯＲＦ编码 相似文献
6.
小金海棠S-腺苷甲硫氨酸合成酶基因（MxSAMS）的克隆和表达分析 总被引：1，自引：1，他引：0
从本实验室建立的小金海棠缺铁差减文库中分离出一个cDNA片段,在GenBank中发现该片段与其它植物的S-腺苷甲硫氨酸合成酶(SAMS)基因具有90%的同源性。利用RACE技术成功地获得小金海棠（Malus xiaojinensis）SAMS基因(MxSAMS)的cDNA全长序列（GenBank登录号：EU639408）,该基因cDNA全长1 479 bp,最大开放阅读框1 176 bp,编码392个氨基酸,酶蛋白理论分子量为42.99 kD;与其它植物的蛋白质氨基酸序列同源性在88.1%~92.6%之间。推测的MxSAMS蛋白质三级结构包含3个保守结构域和一个保守的ATP结合位点GAGDQG。Southern 杂交显示,MxSAMS基因在小金海棠基因组中是单拷贝的。半定量RT-PCR结果表明,该基因在小金海棠的根和叶中均受缺铁胁迫诱导增强表达。 相似文献
7.
Dmrt 基因编码的是一类新的具有锌指结构的转录因子，它们均含有一个DM(Double sex 和Mab - 3) 结构域，在性别分化发育和体节分化等过程中起着重要调控作用。尽管已在多种动物中克隆了Dmrt基因的多个成员，但在贝类中未见任何有关Dmrt基因的报道。本研究通过简并PCR克隆技术，从马氏珠母贝（Pinctada matensii）基因组中克隆到3个不同的DM序列（pmDmrt2，pmDmrt3 pmDmrt4）。证实了在马氏珠母贝基因组中也存在Dmrt基因家族的多个成员。序列分析表明，pmDmrt2编码的氨基酸序列与斑马鱼、爪蟾、红原鸡、家鼠、人等的Dmrt2的一致性为95 %；pmDmrt3编码的氨基酸序列与斑马鱼、青鳉、红原鸡、家鼠、人的Dmrt3的一致性为85%；pmDmrt4编码的氨基酸序列与青鳉、红鳍多纪鲀的Dmrt4一致性高达97%，进一步证明该基因家族在无脊椎动物和脊椎动物都具有高度的进化保守性。 相似文献
8.
油菜叶片衰老相关基因的分离细胞色素P450 cDNA的克隆和序列分析 总被引：2，自引：0，他引：2
通过绿叶和衰老叶片cDNA的缩减杂交和差别筛选,富集并分离了缩减cDNA文库中与油菜叶片衰老有关的基因片段.以目的基因片段为探针,通过筛选油菜衰老叶片的cDNA文库,分离了油菜叶片衰老阶段表达增强的全长cDNA LSC46.DNA序列分析结果表明,LSC46可读框架全长由1509个碱基组成,可以编码503个氨基酸残基,它的核苷酸序列及其推导的氨基酸序列与拟南芥菜依赖于单加氧酶的细胞色素P450的相应序列相比,分别有84.23%和83.50%的同源性. 相似文献
9.
向日葵肌动蛋白基因的cDNA克隆及进化分析 总被引：9，自引：0，他引：9
本研究以向日葵（Helianthus annuus)为材料，提取其总RNA，根据植物肌动蛋白基因编码区的5′和3′末端设计简并引物，利用RT-PCR技术，用5′RACE试剂盒扩增出向日葵肌动蛋白基因编码区全长，以豌豆肌动蛋白cDNA作探针的Southern杂交检测表明扩增出了肌动蛋白基因，将所获片段克隆到pGEM-T载体后进行测序，所得序列与GenBank已知肌动蛋白基因序列的相似性均在60%以上，其中与之相似性最高的锦葵为85%；与主要高等植物肌动蛋白氨基酸序列的相似性达80%以上，根据氨基酸序殖的相似性绘制主要高等植物肌动蛋白的系统树（种系树），表明向日葵肌动蛋白与锦葵肌动蛋白可能由同一祖先进化而来。 相似文献
10.
以高羊茅茎基部组织的mRNA为模板,引用基于多年生黑麦草VRN1基因序列设计的引物,进行RT-PCR分析,同时结合3’RACE和5’RACE方法从高羊茅中扩增出VRN1基因的全长cDNA序列,命名为FaVRN1。该序列cDNA全长1222bp,具有完整的开放阅读框（ORF,152~889bp）,编码蛋白为245个氨基酸,具有典型的MADS-盒和K-盒结构域,有许多磷酸化位点。与其他禾本科植物的春化基因蛋白产物比较,具有高度的保守性,氨基酸序列的同源性都在90%以上。 相似文献
11.
为改善单一菌株发酵制备青稞甜醅的风味与口感,提高其质量品质,本试验采用米根霉和酵母菌为发酵菌株,以氨基酸态氮含量及感官评分为指标,确定混菌发酵黑青稞甜醅的最佳工艺条件,并比较单一菌株发酵黑青稞制品与混菌发酵黑青稞制品中酚类物质含量、抗氧化活性及风味物质组成的差异。结果表明,混菌发酵黑青稞制品最佳发酵条件为:发酵温度33℃,发酵时间48 h,菌种比例(酵母菌J7∶米根霉)1∶1.20,接种量6.81%,在此条件下混菌发酵黑青稞制品的氨基酸态氮含量为9.32 mg·100 g-1,感官评分为95.48分。与单一菌株发酵黑青稞制品相比,混菌发酵黑青稞的黄酮含量(32.22 mg·100 g-1)、 多酚含量(230.68 mg·100 g-1)及DPPH自由基清除能力(95.03 μmol·L-1)显著提高。气相色谱-质谱(GC-MS)分析结果表明,酵母菌单独发酵的黑青稞中共检出33种挥发性风味物质,米根霉单独发酵的黑青稞中共检出41种挥发性风味物质,混菌发酵的黑青稞中共检出46种挥发性风味物质,其中酯类和醇类是3种发酵方式黑青稞制品的主要风味组分。混菌发酵黑青稞的醇类、酯类和酸类种类及含量均显著高于其余两种发酵方式,其相对含量分别达到59.09%、29.44%和6.46%,风味更丰富。综上分析,混菌发酵使黑青稞制品在功能及风味方面具有一定的优势。本研究结果为混菌发酵黑青稞制品的开发和应用奠定了基础。 相似文献
12.
Dark discoloration negatively influences the aesthetic properties of barley‐based food products. The effects of abrasion and heat treatment of grains, exclusion of oxygen, and the use of antibrowning agents on the retardation of darkening in barley flour gel or dough were determined in four types of barley, including hulled proanthocyanidin‐containing and hulled proanthocyanidin‐free, hulless regular, and hulless waxy barley. Abrasion by >30% in hulled barley and by >15% in hulless barley significantly increased the brightness (L*) of barley flour dough by 0.1–7.1. Steam heating of abraded grains also significantly increased the L* of barley flour gels by 1.8–3.4. Ascorbic acid at 1,500 ppm was most effective for retarding discoloration of barley flour dough, followed by 50 ppm of 4‐hexylresorcinol, which is an enzyme competitive inhibitor. The discoloration of barley flour dough was also effectively reduced by storing the dough sheets at 4°C under nitrogen gas to exclude oxygen or under anaerobic conditions at 20°C. Discoloration of barley‐based food products may be effectively controlled by selecting genotypes with low discoloration development such as proanthocyanidin‐free genotypes, by lowering total polyphenol content or polyphenol oxidase (PPO) activity through abrasion, by heat treatment, by exclusion of oxygen, and by the use of enzyme inhibitors. 相似文献
13.
Wet fractionation of barley flours was conducted to identify appropriate fractionation water temperature considering the recovery and purity of starch and protein. In abraded hulless regular barley, yield of starch fraction, starch recovery, and purity of the protein fraction increased from 43.3 to 45.7%, from 61.7 to 64.8%, and from 37.6 to 65.2% when water temperature in fractionation was increased from 23 to 60°C. In abraded hulless waxy barley, recovery of starch with 40°C water was much greater (67.7%) than that at other temperatures (<61.7%). Starch recovery and protein purity of regular barley cultivars were higher than those of waxy barley cultivars with fractionation water of 60°C. In whole hulless barley flours fractionated with 60°C water, waxy barley flours showed similar to or higher protein purity (44.8–48.9%) than regular barley flours (42.8– 44.6%), while regular barley flours exhibited higher starch recovery (>60.6%) than waxy barley flours (<57.3%). The purity of isolated starch was >97.7%, regardless of water temperature and barley type. Considering yield and recovery of the isolated starch, and purity of the isolated protein, 60°C water for hulless regular barley and 40°C for hulless waxy barley seem to be appropriate for fractionation of barley flour for isolation of starch and protein. 相似文献
14.
适度水分亏缺管理提高青稞营养品质和环境效益 总被引：2，自引：0，他引：2
15.
酸法提取青稞麸皮结合酚工艺优化 总被引：2，自引：2，他引：0
为了提高青稞的附加利用价值,该文以青稞麸皮为研究对象,考察了提取试剂、酸质量分数、萃取pH值、料液比和提取温度对多酚质量分数和 DPPH·自由基清除能力的影响。采用中心组合设计优化其结合酚提取工艺。结果表明,青稞结合酚提取最优工艺条件为：提取试剂为硫酸,酸质量分数为11.10%,水料比为1：17 g/mL,提取温度为75℃,pH值不作处理,此条件下提取得到的结合酚质量分数达224.33 mg/(100 g),DPPH·自由基清除能力达9919.28μmol/(100 g),与预测值多酚质量分数243.80 mg/(100 g),其DPPH·自由基清除能力9087.02μmol/(100 g)基本一致。高效液相色谱法检测到最优工艺下所得青稞结合酚中含有8种酚酸及8种黄酮类物质,总量达325.104 mg/(100 g)。研究结果为全面评价青稞结合酚含量及青稞麸皮的高效利用提供科学依据。 相似文献
16.
《Communications in Soil Science and Plant Analysis》2012,43(17-18):3047-3055
Abstract Oat (Avena sativa L.) and waxy hulless barley (Hordeum vulgare L.) are important sources of water soluble plant fiber (ß‐glucan) needed in human diets to lower serum cholesterol. Recent studies have shown grain ß‐glucan content is influenced by soil type and environment, however, nitrogen (N) response data for oat and waxy hulless barley are lacking. In this study, we evaluated N effects on grain ß‐glucan content and yield; grain yield, protein content, and test weight; and total dry matter production and N utilization of oat and waxy hulless barley. Rates of applied N were 0, 34, 67, and 101 kg N/ha at three field environments in central Montana during 1989 and 1990. Nitrogen increased all variables except test weight and ß‐glucan content. Waxy hulless barley grain yields fluctuated from 0.82 to 4.11 Mg/ha, ß‐glucan content from 62 to 76 g/kg, and ß‐glucan yields from 51 to 354 kg/ha. Oat yields ranged from 0.85 to 3.83 Mg/ha, ß‐glucan content from 37 to 51 g/kg, and ß‐glucan yields from 35 to 178 kg/ha. Oat ß‐glucan content was positively related to grain protein content, and waxy hulless barley ß‐glucan content was positively related to test weight. ß‐glucan content appeared more related to environmental factors other than N. 相似文献
17.
为明确青海不同品种黑青稞的营养及化学成分含量,筛选优异种质资源,本研究开展了12种黑青稞营养及化学成分分析与评价。结果表明,参试黑青稞蛋白、总淀粉、直链淀粉、粗脂肪、粗纤维、灰分、β-葡聚糖含量在部分品种间存在显著差异(P<0.05),黑青稞具有较高含量的蛋白质(12.19%~14.07%)、纤维(2.13%~3.64%)、直链淀粉(18.96%~25.94%)和β-葡聚糖(3.91%~7.50%);参试黑青稞中Ca、K、Zn含量存在品种间显著差异(P<0.05),其余测定的矿物质含量存在部分品种间显著差异(P<0.05),其中K(581.42 mg·100g-1)、Mg(171.90 mg·100g-1)、Ca(90.28 mg·100g-1)、Na(17.33 mg·100g-1)含量较高;参试黑青稞蛋白中总必需氨基酸含量平均值为319.90 mg·g-1(接近WHO/FAO推荐值360 mg·g-1),第一限制性氨基酸为赖氨酸,第二限制性氨基酸为甲硫氨酸和胱氨酸,第三限制性氨基酸为苏氨酸;参试部分黑青稞品种的总酚、游离酚、结合酚、总黄酮、游离黄酮、结合黄酮及花色苷含量存在显著差异(P<0.05);主成分筛选出950、Z536、Z533黑青稞综合品质较优,聚类分析将12个黑青稞品种分为4类,第1类蛋白质、多酚、黄酮、β-葡聚糖含量较高;第2类花色苷、氨基酸含量较高;第3类纤维含量较高;第4类淀粉含量较高。本研究结果为黑青稞营养功能品质评价及加工利用奠定了基础,也为特异青稞资源的筛选提供了参考。 相似文献
18.
Cramer AC Mattinson DS Fellman JK Baik BK 《Journal of agricultural and food chemistry》2005,53(19):7526-7531
We identified volatile compounds of barley flour and determined the variation in volatile compound profiles among different types and varieties of barley. Volatile compounds of 12 barley and two wheat cultivars were analyzed using solid phase microextraction (SPME) and gas chromatography. Twenty-six volatiles comprising aldehydes, ketones, alcohols, and a furan were identified in barley. 1-Octen-3-ol, 3-methylbutanal, 2-methylbutanal, hexanal, 2-hexenal, 2-heptenal, 2-nonenal, and decanal were identified as key odorants in barley as their concentration exceeded their odor detection threshold in water. Hexanal (46-1269 microg/L) and 1-pentanol (798-1811 microg/L) were the major volatile compounds in barley cultivars. In wheat, 1-pentanol (723-748 microg/L) was a major volatile. Hulled barley had higher total volatile, aldehyde, ketone, alcohol, and furan contents than hulless barley, highlighting the importance of the husk in barley grain aroma. The proanthocyanidin-free varieties generally showed higher total volatile and aldehyde contents than wild-type varieties, potentially due to decreased antioxidant activity by the absence of proanthocyanidins. 相似文献
19.
Barley grains contain significant amounts of phenolic compounds that may play a major role in the discoloration of food products. Phenolic acid and proanthocyanidin (PA) composition of 11 barley genotypes were determined, using high-performance liquid chromatography and liquid chromatography-mass spectrometry, and their significance on food discoloration was evaluated. Abraded grains contained 146-410 microg/g of phenolic acids (caffeic, p-coumaric, and ferulic) in hulled barley and 182-282 microg/g in hulless barley. Hulled PA-containing and PA-free genotypes had comparable phenolic acid contents. Catechin and six major barley PAs, including dimeric prodelphinidin B3 and procyandin B3, and four trimers were quantified. PAs were quantified as catechin equivalents (CE). The catechin content was higher in hulless (48-71 microg/g) than in hulled (32-37 microg/g) genotypes. The total PA content of abraded barley grains ranged from 169 to 395microg CE/g in PA-containing hulled and hulless genotypes. Major PAs were prodelphinidin B3 (39-109 microg CE/g) and procyanidin B3 (40-99 microg CE/g). The contents of trimeric PAs including procyanidin C2 ranged from 53 to 151 g CE/g. Discoloration of barley flour dough correlated with the catechin content of abraded grains (r = -0.932, P < 0.001), but not with the content of individual phenolic acids and PAs. Discoloration of barley flour dough was, however, intensified when total PA extracts and catechin or dimeric PA fractions were added into PA-free barley flour. The brightness of dough also decreased when the total PA extract or trimeric PA fraction was added into heat-treated PA-free barley flour. Despite its low concentration, catechin appears to exert the largest influence on the discoloration of barley flour dough among phenolic compounds. 相似文献
20.
Yali Li Chunlin Long Kenji Kato Chunyan Yang Kazuhiro Sato 《Genetic Resources and Crop Evolution》2011,58(5):645-655
Hulless barley (Hordeum vulgare L. s. l.) is the staple food crop of Tibetan communities in the Qinghai-Tibet Plateau, covering Tibet, Qinghai, Gansu, Sichuan and Yunnan provinces in China. Participatory Rural Appraisal methodolgies were employed in twenty-seven villages that were randomly selected in Shangri-la region, or Diqing Prefecture of Yunnan Province to document the ethnobotanical and indigenous knowledge related to the production, diversity, use and conservation of hulless barley. For Tibetans in Shangri-la, the crop has a high socio-cultural value. The genetic diversity of landraces managed by the farmers in Shangri-la is an extremely important germplasm resource. We recorded a total of 54 landraces that are primarily described by farmers based on their cooking quality, growth cycle, color and size of the grains. The ethnobotanical and indigenous knowledge recorded in this study contributes to the understanding of the genetic diversity of hulless barley in Shangri-la and even in the Qinghai-Tibet Plateau, and in defining appropriate strategies for its conservation on farm. 相似文献