生物英文文献.doc
微生物专题英文文献
班级：生物工程 学生：马春玲 2013年12月13日
LOGO
试验内容
1. Purpose and meaning 2. Introduction 3. Materials and methods
4.5 正交试验结果
Table 5. Results of ortho.1 Trend curve
Fig.2 Relationship between xylanase and time of fermentation in Aspergillus niger N212
通过对出发菌株注入不同剂量的氮离子，低能氮离子 束对菌体细胞均有一定程度的致死和损伤作用，细胞及其 损伤DNA又在其修复系统的作用下得到不同程度的修复， 从而导致黑曲霉孢子的存活率先下降，后上升，然后又下 降，并且菌种的修复出错会使其突变率大大提高，从而提 高了菌株的正突变率，从而确定了氮离子最佳注入参数。 以上试验可以得出最优培养基的组成（即各组分的最 适浓度），而且在以上培养得到了黑曲霉N212（表2），当 它发酵60个小时后酶活达到600IU/ml，比之前未优化的菌 株减少了12个小时，而且相对于原出发菌株酶活增加了100 ％。 试验证明离子注入对微生物进行诱变改良是一种行之 有效的诱变技术。
木聚糖酶是植物细胞壁的主要之一，属 于非淀粉多糖。可作为生物漂白剂用于造纸工 业，也可用于生物转化等等。目前木聚糖酶的 生产主要还依靠真菌。
对于产酶微生物的育种，国外多采用基因工程手段 构建高产菌，而国内多采用传统的诱变方法，如紫外辐 射、化学诱变剂处理等，这些诱变手段获得的突变株一 般稳定性差、容易产生回复突变且负突变较多及诱变选 育的工作量很大，而20世纪80年代末，人们发现离子束 可以引起靶物质原子移位和重排，使细胞表面刻蚀和穿 孔，并能影响和改变细胞电性等现象，提出了离子束可 以用于细胞加工和基因转移的设想，并陆续得到了研究 证实，由此产生了国内外普遍关注的离子束生物技术工 程学，而且离子束育种是一项具有我国自主知识产权且 被国际所承认的定向遗传改良的集物理诱变和化学诱变 于一身的综合诱变方法，具有损伤小、突变谱广、突变 率高的特点。
(英文)生物外文文献
FIG. 3
SK-BR-3 cell，HER2过表达的乳腺癌细胞，STAT3可以通 过特定的细胞因子激活。HER2是重要的乳腺癌预后判 断因子，HER2阳性（过表达或扩增）的乳腺癌，其临 床特点和生物学行为有特殊表现，治疗模式也与其他 类型的乳腺癌有很大的区别。
36%
FIG. 4 LIF刺激
FIG. 1
15.5%
FIG. 2
GRN knockdown reduced the mRNA expression of these genes, similar to the effects of STAT3 knockdown
58%
染色质免疫共沉淀技术（ chromatin immunoprecipitation assay, CHIP ）
70%
Suggesting that some but not all phenotypes associated with GRN knockdown can be rescued by constitutively active STAT3.
FIG. 6
42.9%
13.5%
These findings indicate that in primary breast cancers, GRN expression specifically correlates with enhanced STAT3 transcriptional activity in the presence of tyrosinephosphorylated STAT3
• 皮尔森相关系数（Pearson correlation coefficient）也称皮尔森积矩 相关系数(Pearson product-moment correlation coefficient) ，是一种 线性相关系数。皮尔森相关系数是用来反映两个变量线性相关程 度的统计量。相关系数用r表示，其中n为样本量，分别为两个变 量的观测值和均值。r描述的是两个变量间线性相关强弱的程度。 r的绝对值越大表明相关性越强。
生物工程英文文献
Abstract. Thermomyces lanuginosus, isolated from
self-heated jute stacks in Bangladesh, was able to produce a very high level of cellulase-free xylanase in shake cultures using inexpensive lignocellulosic biomass. Of the nine lignocellulosic substrates tested, corn cobs were found to be the best inducer of xylanase activity. The laboratory results of xylanase production have been successfully scaled up to V A B I O (VoestAlpine Biomass Technology Center) scale using a 15m 3 fermentor for industrial production and application of xylanase. In addition, some properties of the enzyme in crude culture filtrate produced on corn cobs are presented. The enzyme exhibited very satisfactory storage stability at 4-30°C either as crude culture filtrate or as spray- or freeze-dried powder. The crude enzyme was active over a broad range of pH and had activity optima at pH 6.5 and 70-75 ° C. The enzyme was almost thermostable (91-927/o) at pH 6.5 and 9.0 after 41 h preincubation at 55 ° C and lost only 20-33% activity after 188 h. In contrast, it was much less thermostable at pH 5.0 and 11.0. Xylanases produced on different lignocellulosic substrates exhibited differences in thermostability at 55°C and pH 6.5.
微生物英文文献及翻译—翻译
A/O法活性污泥中氨氧化菌群落的动态与分布摘要：我们研究了在厌氧—好氧序批式反应器（SBR）中氨氧化菌群落（AOB）和亚硝酸盐氧化菌群落（NOB）的结构活性和分布。
在研究过程中，分子生物技术和微型技术被用于识别和鉴定这些微生物。
污泥微粒中的氨氧化菌群落结构大体上与初始的接种污泥中的结构不同。
与颗粒形成一起，由于过程条件中生物选择的压力，AOB的多样性下降了。
DGGE测序表明，亚硝化菌依然存在，这是因为它们能迅速的适应固定以对抗洗涤行为。
DGGE更进一步的分析揭露了较大的微粒对更多的AOB种类在反应器中的生存有好处。
在SBR反应器中有很多大小不一的微粒共存，颗粒的直径影响这AOB和NOB的分布。
中小微粒（直径<0.6mm）不能限制氧在所有污泥空间的传输。
大颗粒（直径>0.9mm）可以使含氧量降低从而限制NOB的生长。
所有这些研究提供了未来对AOB微粒系统机制可能性研究的支持。
关键词：氨氧化菌（AOB），污泥微粒，菌落发展，微粒大小，硝化菌分布，发育多样性1.简介在浓度足够高的条件下，氨在水环境中对水生生物有毒，并且对富营养化有贡献。
因此，废水中氨的生物降解和去除是废水处理工程的基本功能。
硝化反应，将氨通过硝化转化为硝酸盐，是去除氨的一个重要途径。
这是分两步组成的，由氨氧化和亚硝酸盐氧化细菌完成。
好氧氨氧化一般是第一步，硝化反应的限制步骤：然而，这是废水中氨去除的本质。
对16S rRNA的对比分析显示，大多数活性污泥里的氨氧化菌系统的跟ß-变形菌有关联。
然而，一系列的研究表明，在氨氧化菌的不同代和不同系有生理和生态区别，而且环境因素例如处理常量，溶解氧，盐度，pH，自由氨例子浓度会影响氨氧化菌的种类。
因此，废水处理中氨氧化菌的生理活动和平衡对废水处理系统的设计和运行是至关重要的。
由于这个原因，对氨氧化菌生态和微生物学更深一层的了解对加强处理效果是必须的。
当今，有几个进阶技术在废水生物处理系统中被用作鉴别、刻画微生物种类的有价值的工具。
微生物英文文献及翻译—原文
微生物英文文献及翻译—原文本期为微生物学的第二讲，主要讨论炭疽和蛔虫病这两种既往常见而当今社会较为罕见的疾病。
炭疽是由炭疽杆菌所致的一种人畜共患的急性传染病。
人因接触病畜及其产品及食用病畜的肉类而发生感染。
临床上主要表现为皮肤坏死、溃疡、焦痂和周围组织广泛水肿及毒血症症状；似蚓蛔线虫简称蛔虫，是人体内最常见的寄生虫之一。
成虫寄生于小肠，可引起蛔虫病。
其幼虫能在人体内移行，引起内脏幼虫移行症。
案例分析Case 1：A local craftsman who makes garments from the hides of goats visits his physician because over the past few days he has developed several black lesions on his hands and arms. The lesions are not painful, but he is alarmed by their appearance. He is afebrile and his physical examination is unremarkable.案例1：一名使用鹿皮做皮衣的当地木匠来就医，主诉过去几天中手掌和手臂上出现几个黑色皮肤损害。
皮损无痛，但是外观较为骇人。
患者无发热，体检无异常发现。
1. What is the most likely diagnosis?Cutaneous anthrax, caused by Bacillus anthracis. The skin lesions are painless and dark or charred ulcerations known as black eschar. It is classically transmitted by contact with thehide of a goat at the site of a minor open wound.皮肤炭疽：由炭疽杆菌引起，皮损通常无痛、黑色或称为焦痂样溃疡。
生物科学中英文对照外文翻译文献
中英文资料外文翻译文献译文标题：传统意大利榛子的体外繁殖用于当地遗传资源库的稳定和保存译文：关键词：欧洲榛，榛属，传统种质，体外繁殖摘要：在地中海盆地，榛子（欧洲榛）是非常重要的一种作物。
体外繁殖能够有效的稳定当地遗传资源库。
为了提高榛子微组织繁殖实验记录的精确性，各种不同的研究已经在进行。
这些研究通常以重要的品种为材料，然而，微组织繁殖实验记录应用在这些幼小品种上比起传统方法通常会产生相反的结果，这种技术在幼小品种上很少取得成功。
本实验的目的是为重要品种微组织繁殖的操作积累相关的知识和信息。
实验过程中需要设计不同成分的培养基，灭菌时间和培养时间都要进行详细的讨论。
传统意大利品种植株茎芽中的N6-异戊烯腺嘌呤的作用是改善这种状态。
生根阶段是榛属微组织繁殖应用于大型商业生产的关键步骤。
欧洲榛在欧洲特别是生物地理分布区地中海盆地代表一种重要的经济类林木。
榛子主要产于土耳其，意大利，美国和西班牙（分别是每年55,000, 110,000, 25,000, 18,000+吨），其次是法国，希腊，葡萄牙。
大约90%的产品被去皮并且以树芯的形式卖出，然而剩余的10%则作为树苗消费。
极好的营养成分和营养制品的特性也使该物种产生很高的利润。
此外，在一些特有的栽培地区，传统和文化身份严重受榛子产量的影响，文化身份常常会促进贫瘠土地的回收和利用。
即使这样，在一些地区，这种林业作物仍然不是重要的农业资源，然而，就当地足够维持的生产式系统和作为宝贵的食物的传统而言，它却是一种有趣的收入来源。
世界第二大生产商意大利说一些传统的品种主要种植在Campania ,Latium, Piedmont,在西西里岛有大量的属典型种。
近几年，一些主要品种由于质量和传统特性获得了欧洲质量印模。
此外，这些品种还被引进其他国家特定的果园中以增大他们的生长范围。
没有经过检验的物质可能会传播疾病，也可能会导致原因不明的物质的出现。
微组织繁殖法等生物技术的应用会促进健康的合乎本性的物质的产生(Nas et al.,2004)，并且提高这种林木的经济价值。
微生物英文文献及翻译—翻译
A/O法活性污泥中氨氧化菌群落的动态与分布摘要：我们研究了在厌氧—好氧序批式反应器（SBR）中氨氧化菌群落（AOB）和亚硝酸盐氧化菌群落（NOB）的结构活性和分布。
在研究过程中，分子生物技术和微型技术被用于识别和鉴定这些微生物。
污泥微粒中的氨氧化菌群落结构大体上与初始的接种污泥中的结构不同。
与颗粒形成一起，由于过程条件中生物选择的压力，AOB的多样性下降了。
DGGE测序表明，亚硝化菌依然存在，这是因为它们能迅速的适应固定以对抗洗涤行为。
DGGE更进一步的分析揭露了较大的微粒对更多的AOB种类在反应器中的生存有好处。
在SBR反应器中有很多大小不一的微粒共存，颗粒的直径影响这AOB和NOB的分布。
中小微粒（直径<0.6mm）不能限制氧在所有污泥空间的传输。
大颗粒（直径>0.9mm）可以使含氧量降低从而限制NOB的生长。
所有这些研究提供了未来对AOB微粒系统机制可能性研究的支持。
关键词：氨氧化菌（AOB），污泥微粒，菌落发展，微粒大小，硝化菌分布，发育多样性•简介在浓度足够高的条件下，氨在水环境中对水生生物有毒，并且对富营养化有贡献。
因此，废水中氨的生物降解和去除是废水处理工程的基本功能。
硝化反应，将氨通过硝化转化为硝酸盐，是去除氨的一个重要途径。
这是分两步组成的，由氨氧化和亚硝酸盐氧化细菌完成。
好氧氨氧化一般是第一步，硝化反应的限制步骤：然而，这是废水中氨去除的本质。
对16S rRNA的对比分析显示，大多数活性污泥里的氨氧化菌系统的跟ß-变形菌有关联。
然而，一系列的研究表明，在氨氧化菌的不同代和不同系有生理和生态区别，而且环境因素例如处理常量，溶解氧，盐度，pH，自由氨例子浓度会影响氨氧化菌的种类。
因此，废水处理中氨氧化菌的生理活动和平衡对废水处理系统的设计和运行是至关重要的。
由于这个原因，对氨氧化菌生态和微生物学更深一层的了解对加强处理效果是必须的。
当今，有几个进阶技术在废水生物处理系统中被用作鉴别、刻画微生物种类的有价值的工具。
生物科学论文中英文资料外文翻译文献
生物科学论文中英文资料外文翻译文献Carotenoid Biosynthetic Pathway in the Citrus Genus: Number of Copies and Phylogenetic Diversity of Seven GeneThe first objective of this paper was to analyze the potential role of allelic variability of carotenoid biosynthetic genes in the interspecifi diversity in carotenoid composition of Citrus juices. The second objective was to determine the number of copies for each of these genes. Seven carotenoid biosynthetic genes were analyzed using restriction fragment length polymorphism (RFLP) and simple sequence repeats (SSR) markers. RFLP analyses were performed with the genomic DNA obtained from 25 Citrus genotypes using several restriction enzymes. cDNA fragments of Psy, Pds, Zds, Lcyb, Lcy-e, Hy-b, and Zep genes labeled with [R-32P]dCTP were used as probes. For SSR analyses, two primer pairs amplifying two SSR sequences identified from expressed sequence tags (ESTs) of Lcy-b and Hy-b genes were designed. The number of copies of the seven genes ranged from one for Lcy-b to three for Zds. The genetic diversity revealed by RFLP and SSR profiles was in agreement with the genetic diversity obtained from neutral molecμLar markers. Genetic interpretation of RFLP and SSR profiles of four genes (Psy1, Pds1, Lcy-b, and Lcy-e1) enabled us to make inferences on the phylogenetic origin of alleles for the major commercial citrus species. Moreover, the resμLts of our analyses suggest that the allelic diversity observed at the locus of both of lycopene cyclase genes, Lcy-b and Lcy-e1, is associated with interspecific diversity in carotenoid accumμLation in Citrus. The interspecific differences in carotenoid contents previously reported to be associated withother key steps catalyzed by PSY, HY-b, and ZEP were not linked to specific alleles at the corresponding loci.KEYWORDS: Citrus; carotenoids; biosynthetic genes; allelic variability; phylogeny INTRODUCTIONCarotenoids are pigments common to all photosynthetic organisms. In pigment-protein complexes, they act as light sensors for photosynthesis but also prevent photo-oxidat ion induced by too strong light intensities. In horticμLtural crops, they play a major role in fruit, root, or tuber coloration and in nutritional quality. Indeed some of these micronutrients are precursors of vitamin A, an essential component of human and animal diets. Carotenoids may also play a role in chronic disease prevention (such as certain cancers), probably due to their antioxidant properties. The carotenoid biosynthetic pathway is now well established. Carotenoids are synthesized in plastids by nuclear-encoded enzymes. The immediate precursor of carotenoids (and also of gibberellins, plastoquinone, chlorophylls,phylloquinones, and tocopherols) is geranylgeranyl diphosphate (GGPP). In light-grown plants, GGPP is mainly derivedcarotenoid, 15-cis-phytoene. Phytoene undergoes four desaturation reactions catalyzed by two enzymes, phytoene desaturase (PDS) and β-carotene desaturase (ZDS), which convert phytoene into the red-colored poly-cis-lycopene. Recently, Isaacson et al. and Park et al. isolated from tomato and Arabidopsis thaliana, respectively, the genes that encode the carotenoid isomerase (CRTISO) which, in turn, catalyzes the isomerization of poly-cis-carotenoids into all-trans-carotenoids. CRTISO acts on prolycopene to form all-trans lycopene, which undergoes cyclization reactions. Cyclization of lycopene is abranching point: one branch leads to β-carotene (β, β-carotene) and the other toα-carotene (β, ε-carotene). Lycopene β-cyclase (LCY-b) then converts lycopene intoβ-carotene in two steps, whereas the formation of α-carotene requires the action of two enzymes, lycopene ε- cyclase (LCY-e) and lycopene β-cyclase (LCY-b). α- carotene is converted into lutein by hydroxylations catalyzed by ε-carotene hydroxylase (HY-e) andβ-carotene hydroxylase (HY-b). Other xanthophylls are produced fromβ-carotene with hydroxylation reactions catalyzed by HY-b and epoxydation catalyzed by zeaxanthin epoxidase (ZEP). Most of the carotenoid biosynthetic genes have been cloned and sequenced in Citrus varieties . However, our knowledge of the complex regμLation of carotenoid biosynthesis in Citrus fruit is still limited. We need further information on the number of copies of these genes and on their allelic diversity in Citrus because these can influence carotenoid composition within the Citrus genus.Citrus fruit are among the richest sources of carotenoids. The fruit generally display a complex carotenoid structure, and 115 different carotenoids have been identified in Citrus fruit. The carotenoid richness of Citrus flesh depends on environmental conditions, particμLarly on growing conditions and on geogr aphical origin . However the main factor influencing variability of caro tenoid quality in juice has been shown to be genetic diversity. Kato et al. showed that mandarin and orange juices accumμLated high levels of β-cryptoxanthin and violaxanthin, respectively, whereas mature lemon accumμLated extremely low levels of carotenoids. Goodner et al. demonstrated that mandarins, oranges, and their hybrids coμLd be clearly distinguished by theirβ-cryptoxanthin contents. Juices of red grapefruit contained two major carotenoids: lycopene and β-carotene. More recently, we conducted a broad study on the organization of the variability of carotenoid contents in different cμLtivated Citrus species in relation with the biosynthetic pathway . Qualitative analysis of presence or absence of the different compounds revealed three main clusters: (1) mandarins, sweet oranges, and sour oranges;(2) citrons, lemons, and limes; (3) pummelos and grapefruit. Our study also enabled identification of key steps in the diversification of the carotenoid profile. Synthesis of phytoene appeared as a limiti ng step for acid Citrus, while formation of β-carotene and R-carotene from lycopene were dramatically limited in cluster 3 (pummelos and grapefruit). Only varieties in cluster 1 were able to produce violaxanthin. In the same study , we concluded that there was a very strong correlation between the classification of Citrus species based on the presence or absence of carotenoids (below,this classification is also referred to as the organization of carotenoid diversity) and genetic diversity evaluated with bi ochemical or molecμLar markers such as isozymes or randomLy amplified polymorphic DNA (RAPD). We also concluded that, at the interspecific level, the organization of the diversity of carotenoid composition was linked to the global evolution process of cμLt ivated Citrus rather than to more recent mutation events or human selection processes. Indeed, at interspecific level, a correlation between phenotypic variability and genetic diversity is common and is generally associated with generalized gametic is common and is generally associated with generalized gametic disequilibrium resμLting from the history of cμLtivated Citrus. Thus from numerical taxonomy based on morphologicaltraits or from analysis of molecμLar markers , all authors agreed on the existence o f three basic taxa (C. reticμLata, mandarins; C. medica, citrons; and C. maxima, pummelos) whose differentiation was the resμLt of allopatric evolution. All other cμLtivated Citrus specie s (C. sinensis, sweet oranges; C. aurantium, sour oranges;C. paradi si, grapefruit; and C. limon, lemons) resμLted from hybridization events within this basic pool except for C. aurantifolia, which may be a hybrid between C. medica and C. micrantha .Our p revious resμLts and data on Citrus evolution lead us to propose the hypothesis that the allelic variability supporting the organization of carotenoid diversity at interspecific level preceded events that resμLted in the creation of secondary species. Such molecμLar variability may have two different effects: on the one hand, non-silent substitutions in coding region affect the specific activity of corresponding enzymes of the biosynthetic pathway, and on the other hand, variations in untranslated regions affect transcriptional or post-transcriptional mechanisms.There is no available data on the allelic diversity of Citrus genes of the carotenoid biosynthetic pathway. The objective of this paper was to test the hypothesis that allelic variability of these genes partially determines phenotypic variability at the interspecific level. For this purpose, we analyzed the RFLPs around seven genes of the biosynthetic pathway of carotenoids (Psy, Pds, Zds, Lcy-b, Lcy-e, Hy-b, Zep) and the polymorphism of two SSR sequences found in Lcy-b and Hy-b genes in a representative set of varieties of the Citrus genus already analyzed for carotenoid constitution. Our study aimed to answer the following questions: (a) are those genes mono- or mμLtilocus, (b) is the polymorphism revealed by RFLP and SSR markers inagreement with the general histor y of cμLtivated Citrus thus permitting inferences about the phylogenetic origin of genes of the secondary species, and (c) is this polymorphism associated with phenotypic (carotenoid compound) variations.RESΜLTS AND DISCUSSIONGlobal Diversity of the Genotype Sample Observed by RFLP Analysis. RFLP analyses were performed using probes defined from expressed sequences of seven major genes of the carotenoid biosynthetic pathway . One or two restriction enzymes were used for each gene. None of these enzymes cut the cDNA probe sequence except HindIII for the Lcy-e gene. Intronic sequences and restriction sites on genomic sequences werescreened with PCR amplification using genomic DNA as template and with digestion of PCR products. The resμLts indicated the absence of an intronic sequence for Psy and Lcy-b fragments. The absence of intron in these two fragments was checked by cloning and sequencing corresponding genomic sequences (data not shown). Conversely, we found introns in Pds, Zds, Hy-b, Zep, and Lcy-e genomic sequences corresponding to RFLP probes. EcoRV did not cut the genomic sequences of Pds, Zds, Hy-b, Zep, and Lcy-e. In the same way, no BamHI restriction site was found in the genomic sequences of Pds, Zds, and Hy-b. Data relative to the diversity observed for the different genes are presented in Table 4. A total of 58 fragments were identified, six of them being monomorphic (present in all individuals). In the limited sample of the three basic taxa, only eight bands out of 58 coμLd not be observed. In the basic taxa, the mean number of bands per genotype observed was 24.7, 24.7, and 17 for C. reticμLata, C. maxima, and C. medica, respectively. It varies from28 (C. limettioides) to 36 (C. aurantium) for the secondary species. The mean number of RFLP bands per individual was lower for basic taxa than for the group of secondary species. This resμLt indicates that secondary species are much more heterozygous than the basic ones for these genes, which is logical if we assume that the secondary species arise from hybridizations between the three basic taxa. Moreover C. medica appears to be the least heterozygous taxon for RFLP around the genes of the carotenoid biosynthetic pathway, as already shown with isozymes, RAPD, and SSR markers.The two lemons were close to the acid Citrus cluster and the three sour oranges close to the mandarins/sweet oranges cluster. This organization of genetic diversity based on the RFLP profiles obtained with seven genes of the carotenoid pathway is very similar to that previously obtained with neutral molecμLar markers such as genomic SSR as well as the organization obtained with qualitative carotenoid compositions. All these resμLts suggest that the observed RFLP and SSR fragments are good phylogenetic markers. It seems consistent with our basic hypothesis that major differentiation in the genes involved in the carotenoid biosynthetic pathway preceded the creation of the secondary hybrid species and thus that the allelic structure of these hybrid species can be reconstructed from alleles observed in the three basic taxa.Gene by Gene Analysis: The Psy Gene. For the Psy probe combined with EcoRV or BamHI restriction enzymes, five bands were identified for the two enzymes, and two to three bands were observed for each genotype. One of these bands was present in all individuals. There was no restriction site in the probe sequence. These resμLts lead us to believe that Psy is present at two loci,one where no polymorphism was found with the restriction enzymes used, and one that displayed polymorphism. The number of different profiles observed was six and four with EcoRV and BamHI, respectively, for a total of 10 different profiles among the 25 individuals .Two Psy genes have also been found in tomato, tobacco, maize, and rice . Conversely, only one Psy gene has been found in Arabidopsis thaliana and in pepper (Capsicum annuum), which also accumμLates carotenoids in fruit. According to Bartley and Scolnik, Psy1 was expressed in tomato fruit chromoplasts, while Psy2 was specific to leaf tissue. In the same way, in Poaceae (maize, rice), Gallagher et al. found that Psy gene was duplicated and that Psy1 and notPsy2 transcripts in endosperm correlated with endosperm carotenoid accumμLation. These resμLts underline the role of gene duplication and the importance of tissue-specific phytoene synthase in the regμLation of carotenoid accumμLation.All the polymorphic bands were present in the sample of the basic taxon genomes. Assuming the hypothesis that all these bands describe the polymorphism at the same locus for the Psy gene, we can conclude that we found allelic differentiation between the three basic taxa with three alleles for C. reticμLata, four for C. maxima, and one for C. medica.The alleles observed for the basic taxa then enabled us to determine the genotypes of all the other species. The presumed genotypes for the Psy polymorphic locus are given in Table 7. Sweet oranges and grapefruit were heterozygous with one mandarin and one pummelo allele. Sour oranges were heterozygous; they shared the same mandarin allele with sweet oranges but had a different pummelo allele. Clementine was heterozygous with two mandarin alleles; one shared with sweetoranges and one with “Willow leaf” mandarin. “Meyer” lemon was heterozygous, with the mandarin allele also found in sweet oranges, and the citron allele. “Eureka”lemon was also heterozygous with the same pummelo allele as sour oranges and the citron allele. The other acid Citrus were homozygous for the citron allele.The Pds Gen. For the Pds probe combined with EcoRV, six different fragments were observed. One was common to all individuals. The number of fragments per individual was two or three. ResμLts for Pds led us to believe that this gene is present at two loci, one where no polymorphism was found with EcoRV restriction, and one displaying polymorphism. Conversely, studies on Arabidopsis, tomato, maize, and rice showed that Pds was a single copy gene. However, a previous study on Citrus suggests that Pds is present as a low-copy gene family in the Citrus genome, which is in agreement with our findings.The Zds Gene. The Zds profiles were complex. Nine and five fragments were observed with EcoRV and BamHI restriction, respectively. For both enzymes, one fragment was common to all individuals. The number of fragments per individual ranged from two to six for EcoRV and three to five for BamHI. There was no restriction site in the probe sequence. It can be assumed that several copies (at least three) of the Zds gene are present in the Citrus genome with polymorphism for at least two of them. In Arabidopsis, maize, and rice, like Pds, Zds was a single-copy gene .In these conditions and in the absence of analysis of controlled progenies, we are unable to conduct genetic analysis of profiles. However it appears that some bands differentiated the basic taxa: one for mandarins, one for pummelos, and one for citrons with EcoRV restriction and one for pummelos and onefor citrons with BamHI restriction. Two bands out of the nine obtained with EcoRV were not observed in the samples of basic taxa. One was rare and only observed in “Rangpur” lime. The other was found in sour oranges, “V olkamer” lemon,and “Palestine sweet” lime suggesting a common ancestor for these three genotypes.This is in agreement with the assumption of Nicolosi et al. that “V olkamer” lemon resμLts from a complex hybrid combination with C. aurantium as one parent. It will be necessary to extend the analysis of the basic taxa to conclude whether these specific bands are present in the diversity of these taxa or resμLt from mutations after the formation of the secondary species.The Lcy-b Gene with RFLP Analysis.After restriction with EcoRV and hybridization with the Lcy-b probe, we obtained simple profiles with a total of four fragments. One to two fragments were observed for each individual, and seven profiles were differentiated among the 25 genotypes. These resμLts provide evidence that Lcy-b is present at a single locus in the haploid Citrus genome. Two lycopene β-cyclases encoded by two genes have been identified in tomato. The B gene encoded a novel type of lycopene β-cyclase whose sequence was similar to capsanthin-capsorubin synthase. The B gene expressed at a high level in βmutants was responsible for strong accumμLation ofβ-carotene in fruit, while in wild-type tomatoes, B was expressed at a low level.The Lcy-b Gene with SSR Analysis. Four bands were detected at locus 1210 (Lcy-b gene). One or two bands were detected per variety confirming that this gene is mono locus. Six different profiles were observed among the 25 genotypes. As with RFLPanalysis, no intrataxon molecμLar polymorphism was found within C. Paradisi, C. Sinensis, and C. Aurantium.Taken together, the information obtained from RFLP and SSR analyses enabled us to identify a complete differentiation among the three basic taxon samples. Each of these taxons displayed two alleles for the analyzed sample. An additional allele was identified for “Mexican” l ime. The profiles for all secondary species can be reconstructed from these alleles. Deduced genetic structure is given in. Sweet oranges and clementine were heterozygous with one mandarin and one pummelo allele. Sour oranges were also heterozygous sharing the same mandarin allele as sweet oranges but with another pummelo allele. Grapefruit were heterozygous with two pummelo alleles. All the acid secondary species were heterozygous, having one allele from citrons and the other one from mandarins except for “Mexican” lime, which had a specific allele.柑桔属类胡萝卜素生物合成途径中七个基因拷贝数目及遗传多样性的分析摘要：本文的首要目标是分析类胡萝卜素生物合成相关等位基因在发生变异柑橘属类胡萝卜素组分种间差异的潜在作用；第二个目标是确定这些基因的拷贝数。
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Application of α-amylase and Researchα-amylase to be widely distributed throughout microorganisms to higher plants. The International Enzyme classification number is EC. 3.2.1.1, acting on the starch from the starch molecules within the random cut α a 1,4 glycosidic bond to produce dextrin and reducing sugar, because the end product of carbon residues as Α configuration configuration, it is called α-amylase. Now refers to α-amylase were cut from the starch molecules within the α-1,4 glycosidic bond from the liquefaction of a class of enzymes.α-amylase is an important enzyme, a large number of used food processing, food industry, brewing, fermentation, textile industry and pharmaceutical industries, which account for the enzyme about 25% market share. Currently, both industrial production to large-scale production by fermentation α-amylase. α-amylase in industrial applications1.1 The bread baking industry, as a preservative enzymes used in baking industry, production of high quality products have been hundreds of years old. In recent decades, malt and microbial α-amylase, α-amylase is widely used in baking industry. The enzymes used for making bread, so that these products are much larger, better colors, more soft particles.Even today, baking industry have been α-amylase from barley malt and bacterial, fungal leaf extract. Since 1955 and after 1963 in the UK GRAS level validation, fungal amylase, has served as a bread additive. Now, they are used in different areas. Modern continuous baking process, add in f lour α-amylase can not only increase the fermentation rate and reduce dough viscosity (improving product volume and texture) to increase the sugar content in the dough, improved bread texture, skin color and baking quality, but also to extend the preservation time for baked goods. In the storage process, the bread particles become dry, hard, not crisp skin, resulting in deterioration of the taste of bread. These changes collectively referred to as degenerate. Each year simply because the losses caused by deterioration of bread more than 100 million U.S. dollars. A variety of traditional food additives are used to prevent deterioration and improve the texture and taste of baked goods. Recently, people started to pay attention enzyme as a preservative, preservative agent in improving the role of the dough, as amylopectin, amylase enzyme and a match can be effectively used as a preservative. However, excessive amylase causes a sticky bread too. Therefore, the recent trend is the use of temperature stability (ITS) α a amylase activity are high in starch liquefaction, but the baking process is completed before the inactivation. Despite the large number of microbes have been found to produce α-amylase, but with the temperature stability of the nature of the α-amylase only been found in several microorganisms.1.2 starch liquefaction and saccharification of the main α-amylase starch hydrolysis product market, such as glucose and fructose. Starch is converted into high fructose corn syrup (HFCS). Because of their high sweetness, are used in the soft drink beverage industry sweeteners. The liquefaction process is used in thermal stability at high temperature α-amylase. α-amylase in starch liquefaction ofthe application process is already quite mature, and many relevant reports.1.3 fiber desizing modern fiber manufacturing process in knitting yarn in the process will produce large amounts of bacteria, to prevent these yarn faults, often increase in the surface layer of the yarn can remove the protective layer. The surface layer of the material there are many, starch is a very good choice because it is cheap and easy to obtain, and can be easily removed. Starch desizing α-amylase can be used, it can selectively remove the starch without harming the yarn fibers, but also random degradation of starch dextrin soluble in water, and are easily washed off. 1.4 Paper Industry amylase used in the paper industry mainly to improve the paper coating starch. Paste on the paper is primarily to protect the paper in the process from mechanical damage, it also improved the quality of finished paper. Paste to improve the hardness and strength of paper, enhanced erasable paper, and is a good paper coating. When the paper through two rolls, the starch slurry is added the paper. The process temperature was controlled at 45 ~ 6O ℃, need a stable viscosity of starch. Grinding can also be controlled according to different grades of paper starch viscosity. Nature of the starch concentration is too high for the sizing of paper, you can use part of α-amylase degradation of starch to adjust.1.5 Application of detergents in the enzyme is a component of modern high-efficiency detergents. Enzymes in detergents in the most important function is to make detergents more modest sound. Automatic dishwasher detergents early is very rough, easy to eat when the body hurts, and on ceramics, wood tableware can also cause damage. α-amylase was used from 1975 to washing powder. Now, 90% of the liquid detergents contain an amylase, and automatic dishwasher detergents α-amylase on demand is also growing. α 1 amylase ca2 + is too sensitive to low ca2 + in the stability of poor environment, which limits an amylase in the remover in. And, most of the wild-type strains produced an amylase on raw materials as one of the oxidants detergents are too sensitive. Keep household detergents, this limitation by increasing the number of process steps can be improved. Recently, two major manufacturers of detergents NovozymesandGcncncoreInternational enzyme protein technology has been used to improve the stability of amylase bleaching. They leucine substitution of Bacillus licheniformis α-amylase protein in the first 197 on the methionine, resulting in enzymes of the oxidant component of resistance increased greatly enhanced the oxidation stability of the enzyme stability during storage better. The two companies have been pushing in the market these new products.1.6 Pharmaceutical and clinical chemical analysis with the continuous development of biological engineering, the application of amylase involved in many other areas, such as clinical, pharmaceutical and analytical chemistry. Have been reported, based on the liquid α-amylase stability of reagents have been applied to automatic biochemical analyzer (CibaComingExpress) clinical chemistry system. Amylase has been established by means of a method of detecting a higher content of oligosaccharides, is said this method is more than the effective detection method of silver nitrate.2.1 Research amylase α-amylase enzymes in domestic production and application in 1965, China began to apply for a 7658 BF Bacillus amyloliquefaciens amylase production of one, when only exclusive manufacturing plant in Wuxi Enzyme. 1967 Hangzhou Yi sugar to achieve the application of α-amylase production of caramel new technology can save 7% ~ 10% malt, sugar, increase the rate of 10%.1964, China began a process of enzymatic hydrolysis of starch production of glucose. In September l979 injection of glucose by the enzyme and identification of new technology and worked in North China Pharmaceutical Factory, Hebei Dongfeng Pharmaceutical Factory, Zhengzhou Songshan applied pharmaceutical units and achieved good economic benefits. Compared with the traditional acid to improve the yield of 10% Oh, cost more than 15%. In addition to enzyme for citric acid production in China, glutamic acid fermentation system for beer saccharification, fermentation, rice wine, soy sauce manufacture, vinegar production also has been studied and put into production successfully.2.2 Overseas Researc h α-amylase, present, and in addition a large number of T for conventional mutation breeding, the overseas production has been initially figure out the regulation of α-amylase gene, the transduction of the transformation and gene cloning techniques such as breeding. The Bacillus subtilis recombinant gene into the production strain to increase α-amylase yield of 7 to 10 times and has been used in food and the wine industry, for breeding high-yield strains of α-amylase to create a new way.2.3 domestic and foreign research institutions and major research direction as α-amylase is an important value of industrial enzymes, weekly discussion group and outside it was a lot of research. Representative of the domestic units: Sichuan University, major research produc tion of α-amylase strains and culture conditions; Jiangnan University, the main research structure of α-amylase and application performance, such as heat resistance, acid resistance; Northwest universities, major research denatured α-amylase and the environment on the mechanism of α-amylase; South China University of Technology, the main α-amylase of immobilization and dynamic nature; there Huazhong Agricultural University, Chinese Academy of Sciences Institute of Applied Ecology in Shenyang, Tianjin University, Nankai University, College of Life Sciences, Chinese Academy of Agricultural Sciences, Chinese Academy of Sciences Institute of Microbiology and a number of research institutions on a variety of bacterial α-amylase production of a amylase gene cloning and expression. Representative of foreign research units are: Canada UniversityofBritishColumbia, they were a pancreatic amylase structure and mechanism of in-depth research; Denmark's Carlsberg Research Laboratory of the main structure of barley α-amylase domain and binding sites; U.S. WesternRegionalResearchCenter major study α-amylase in barley and the role of antibiotics and the barley α-amylase active site.3, α-amylase conclusion has become the industrial application of one of the most important enzymes, and a large number of micro-organisms can be used for efficient production of amylase, but large-scale commercial production of the enzyme is still limited to some specific fungi and bacteria. For the effective demandfor α-amylase more and more, this enzyme by chemical modification of existing or improved technology through the white matter are. Benefit from the development of modern biotechnology, α an amylase in the pharmaceutical aspects of growing importance. Of course, the food and starch indust ries is still the main market, α amylase in these areas, a demand is still the largest.Journal of Southeast University(English Edition)2008 24（4）。