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用引物SMNUR101和NS6对大粉瘤菌小亚基rDNA进行了PCR扩增,取得成功,片段长度为1400~1500bp。用一对引物扩得大粉瘤菌这样长的小亚基片段,在国内外还属首次。 相似文献
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鸡眼草根瘤菌的16SrDNA全序列分析 总被引:1,自引:1,他引:1
Based on the previous studies on numerical taxonomy, SDS-PAGE of whole-cell protein and DNA hybridization, the rhizobial strains isolated from Kummerowia sp. in semi-arid area of North-west constituted a new subgroup, the 16S rDNA sequence of representative strain SH714 were tested. The unrooted phylogenetic tree was produced. In this tree, the strain SH714 with Sinorhizobium xinjiangensis, S. fredii, S. meliloti, S. medicae, S. saheli and S. teranga constituted a branch of Sinorhizobium. Within this branch, the similarity valuse of 16S rDNA sequence between strain SH714 and S. xinjiangesis, S. fredii, S. meliloti, S. medicae, S. saheli and S. teranga were 97.4%, 97.5%, 96.8%, 96.7%, 97.2% and 95.6% respectively, the values were more than 95%, this indicated that these known species should belong to the same genus. The values of DNA homology between type strains of these species were less than 70%. Thus, the strain SH714 represented a new rhizobial species, and there were some diversity between SH714 and known rhizobial species in phenotypic feature and composition of protein. 相似文献
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香蕉束顶病(BBT)是一种发生在蕉类作物的严重病害。从带有典型香蕉束顶病症状的香蕉植株中按照检测植原体的方法提取DNA,扩增患病植株中植原体16SrDNA片段,证明香蕉束顶病中有植原体存在。对此扩增片段进行限制性酶切片段长度多态性(RFLP)分析和核酸序列分析,并与已知植原体的序列进行同源性比较,构建进化树。结果显示该片段与Gr1的亲缘关系最近。 相似文献
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西部某些根瘤菌的数值分类和16S rDNA PCR-RFLP分析 总被引:7,自引:0,他引:7
选用61株分离自我国西北地区的野豌豆、棘豆、苜蓿和草木樨根瘤菌和4株已知参比菌株,进行了营养利用、抗生素抗性和耐逆性等13个表型性状研究,通过MINTS软件分析,得到了数值分类树状图,发现全部供试菌株在79%的相似性水平上,分为5个群。对57株未知菌株和10株参比菌株16SrDNAPCR-RFLD分析,发现共具有20个遗传图谱类型,聚类分析树状图表明所有菌株共分为5个系统发育分支,与数值分类结果有较好的一致性。 相似文献
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Molecular environmental sampling of the phototrophic complexity in a given environment may be important in a number of research disciplines. Because of the broad evolutionary diversity of photosynthetic organisms, however, primers that can recover sequences from all phototrophs also target other organisms, often preferentially. Therefore, PCR primers that selectively amplify genes of phototrophs over those of other prokaryotic and eukaryotic organisms could prove extremely useful. Here we report two such primers that target 16S rDNA from Cyanobacteria and eukaryotic plastids, but do not amplify genes from abundant Bacteria in a mixed sample. 相似文献
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利用16SrDNA建立种特异性PCR快速检测鸭疫里默氏菌 总被引:3,自引:0,他引:3
鸭疫里默氏菌感染是危害养鸭业的主要疾病,用表型指标鉴定鸭疫里默氏菌存在不足,因此有必要建立检测该菌的种特异性PCR法。利用已登录的鸭疫里默氏菌、大肠杆菌、沙门氏菌、多杀性巴氏杆菌的16S rDNA基因序列,设计了一对鸭疫里默氏菌16S rDNA基因的特异性引物190f和843r,分别以基因组DNA和菌落提取液为模板,从1-19型鸭疫里默氏菌参考菌株和代表亚型、变异株和可能新型的国内分离株共26株细菌中均扩增出大小为654bp的特异性片段,而扩增鸭大肠杆菌、鸭沙门氏菌和禽多杀性巴氏杆菌等感染鸭的常见细菌的结果均呈阴性。分别将鸭疫里默氏菌基因组DNA和菌落提取液进行10倍梯度稀释,基因组DNA的最小检出量为50pg,菌落最小检出量为15CFU/mL。结果说明,该PCR法具有较好的特异性和敏感性,可用于快速鉴定鸭疫里默氏菌。 相似文献
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利用16S rDNA建立种特异性PCR快速检测鸭疫里默氏菌 总被引:13,自引:0,他引:13
鸭疫里默氏菌感染是危害养鸭业的主要疾病,用表型指标鉴定鸭疫里默氏菌存在不足,因此有必要建立检测该菌的种特异性PCR法。利用已登录的鸭疫里默氏菌、大肠杆菌、沙门氏菌、多杀性巴氏杆菌的16S rDNA基因序列,设计了一对鸭疫里默氏菌16S rDNA基因的特异性引物190f和843r,分别以基因组DNA和菌落提取液为模板,从1~19型鸭疫里默氏菌参考菌株和代表亚型、变异株和可能新型的国内分离株共26株细菌中均扩增出大小为654bp的特异性片段,而扩增鸭大肠杆菌、鸭沙门氏菌和禽多杀性巴氏杆菌等感染鸭的常见细菌的结果均呈阴性。分别将鸭疫里默氏菌基因组DNA和菌落提取液进行10倍梯度稀释,基因组DNA的最小检出量为50pg,菌落最小检出量为15CFU/mL。结果说明,该PCR法具有较好的特异性和敏感性,可用于快速鉴定鸭疫里默氏菌。 相似文献
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基于16S rDNA序列探讨十种臂尾轮虫的系统关系和分类地位 总被引:1,自引:0,他引:1
通过对角突臂尾轮虫、尾突臂尾轮虫、裂足臂尾轮虫、剪形臂尾轮虫、方形臂尾轮虫、壶状臂尾轮虫、红臂尾轮虫、镰肜臂尾轮虫、萼花臂尾轮虫和十指臂尾轮虫等十种臂尾轮虫和大肚须足轮虫的线粒体16s rDNA进行扩增和序列测序,结合Genebank 中十指臂尾轮虫的16S rDNA序列,使用MAGE软件构建了NJ(neighbor-joining method)树,使用mrbayes软件构建了贝叶斯树,探讨了十种臂尾轮虫之间的系统关系.结果表明,本研究所涉及的轮虫16S rDNA序列差异百分比均值为14.6%,可作为分子标记应用于轮虫属内种间系统关系研究;系统树均支持将十指臂尾轮虫、裂足臂尾轮虫隶属于臂尾轮属;壶状臂尾轮虫和红臂尾轮虫是两个独立的种.此外,还依据16S rDNA序列变异百分比推测了十种臂尾轮虫的分化时间. 相似文献
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The traditional phylogeny of the coral-inhabiting barnacles, the Pyrgomatidae, is based on morphological characteristics, mainly of the hard parts. It has been difficult to establish the phylogenetic relationships among Pyrgomatidae because of the apparent convergence of morphological characteristics, and due to the use of non-cladistic systematics, which emphasize ancestor-descendant relationships rather than sister-clade relationships. We used partial sequences of two mithochondrial genes, 12S rDNA and 16S rDNA, and a nuclear gene, 18S rDNA, to infer the molecular phylogeny of the pyrgomatids. Our phylogenetic results allowed us to reject previous classifications of Pyrgomatidae based on morphological characteristics. Our results also suggested the possibility of paraphyly of the Pyrgomatidae. The hydrocoral barnacle Wanella is not found on the same clade as the other pyrgomatids, but rather, with the free-living balanids. The basal position of Megatrema and Ceratoconcha is supported. The archeaobalanid Armatobalanus is grouped with Cantellius at the base of the Indo-Pacific pyrgomatines. Fusion of the shell plate and modification of the opercular valves are homoplasious features that occurred more than three times on different clades. The monophyly of the "Savignium" group, comprising four nominal genera, is also not supported, and the different taxa are placed on different clades. 相似文献
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在表型性状数值分析和AFLP指纹图谱分析的基础上,选取54株斜茎黄芪根瘤菌的代表菌株及已知根瘤菌参比菌株,进行16SrDNA和23SrDNA的PCR-RFLP比较分析。结果表明斜茎黄芪根瘤菌具有极大的系统发育多样性,分别具有24个16SrDNA遗传图谱类型和22个23SrDNA遗传图谱类型,16SrDNA与23SrDNAPCR-RFLP聚类分析树状图谱有较好的一致性,但也存在一些差异。在对较大类群的划分上,它们的结果与表型性状数值分析结果有较好的一致性。将16SrDNA和23SrDNAPCR-RFLP分析数据合并在一起进行分析时,得出26个综合遗传图谱类型和1个综合聚类分析树状图谱。很明显,16SrDNA与23SrDNA的合并,能够得出更可靠的系统发育结论。 相似文献
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新疆地区盐湖的中度嗜盐菌的16S rDNA PCR—RFLP分析 总被引:6,自引:0,他引:6
对来自新疆地区艾丁湖、艾比湖和玛那斯盐湖等盐湖的28株中度嗜盐菌与9株相关的参比菌株,进行了16S rDNA PCR-RFLP分析,这些菌株是革兰氏阴性杆菌,能在0~25%NaCl中生长。在实验中,选用4种限制性内切酶AluⅠ、HinfⅠ、RsaⅠ和HaeⅢ,将供试菌株的16S rDNA的PCR产物进行酶切,用3%的琼脂糖电泳分析酶切产物。结果表明,在74%的相似性水平上分为3群。群Ⅰ包括新分离的 相似文献
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The challenge in the development of universal algal primers lies in the genetic diversity contained within the vast array of evolutionary lineages present in this informally named group of organisms. A comparative genomics approach was used previously to identify conserved primers flanking a region of the plastid genome. Our present research illustrates the feasibility of amplifying and sequencing this marker across multiple algal lineages. We present a preliminary framework of 107 novel sequences of this region from 62 red algae, 19 green algae, 14 brown algae, 8 cyanobacteria, 2 diatoms, 1 xanthophyte, and 1 euglenoid, and illustrate levels of divergence of the marker for well‐represented groups in a neighbor‐joining analysis. This ~410 nt region distinguishes most species included in the analysis. The remarkable universality of these primers suggests potential for their use in assays of environmental samples in which they could be used to simultaneously detect a number of different algal lineages. 相似文献
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沙坡头地区根瘤菌DNA同源性及16SrDNA全序列 总被引:2,自引:0,他引:2
数值分类和多位点酶电泳分析表明,分离自宁夏沙坡头
地区的12株根瘤菌构成一个独立的表观群。对这一菌群进行了DNA同源性和群内中心菌株1
6SrDNA全序列分析。12个菌株的G+C mol%在56.4~62.2范围内;群内DNA同源性为72.3%
~9.5%,大于70%,属种内水平;中心株N220的16SrDNA全序列与参比菌株的序列比较,从
模拟系统发育树看出,它与三株土壤杆菌、三株根瘤菌的16SrDNA序列同源性在94.8%~99
.2%的相似性水平上构成一个分支,看来沙坡头地区这群根瘤菌是一个独立的新种群。 相似文献
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Through multiple alignment analysis of 16S rDNA sequences from all known genera of Cytophaga–Flavobacteria (CF) cluster, a new primer pair specifically targeting this cluster was developed, greatly facilitating their diversity and function's exploration in marine ecosystems. Compared with previously reported primers, the new primer pair could theoretically retrieve broader CF diversity without decreasing specificity. The effectiveness for field samples was further evaluated by testing the community DNA samples from various marine environments using the optimal polymerase chain reaction (PCR) conditions established in this work. The results showed its robustness and high specificity for amplifying CF cluster's 16S rDNA fragments from complex marine environments. 相似文献
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16S rDNA用作荧光定量PCR靶基因快速检测铜绿假单胞菌 总被引:2,自引:0,他引:2
对20余种细菌16SrDNAs进行多序列比对与进化树分析,设计铜绿假单胞菌(Pseudomonasaeruginosa,PA)荧光定量PCR(fluorescencequantitativePCR,FQ-PCR)特异性引物。提取PA基因组DNA,以特异性引物扩增16SrDNA靶片段,并构建重组质粒pMDT-Pfr。将梯度稀释的pMDT-Pfr质粒作为模板,用于建立定量标准曲线。以SYBRGreenI荧光染料建立20μL反应体系,对不同浓度的PADNA样品进行FQ-PCR检测。同时,以金黄色葡萄球菌、伤寒杆菌、福氏志贺菌、变形杆菌、表皮葡萄球菌、大肠杆菌和结核杆菌的基因组DNA作阴性对照,验证FQ-PCR方法检测PA的特异性。结果显示,设计的FQ-PCR引物的靶向序列,仅对PA16SrDNA有高度同源性;FQ-PCR方法检测PA,其灵敏度达3.6pg/μL的基因组DNA或(2.1×103±3.1×102)拷贝/μL的16SrDNA基因,并且具有很强的特异性;从细菌DNA提取到FQ-PCR检测,可在2h左右完成PA鉴定。较传统的培养鉴定法而言,以16SrDNA作为FQ-PCR靶基因快速检测PA,具有很好的研究价值与应用前景。 相似文献
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极端嗜盐菌 16S rDNA的PCR扩增 总被引:4,自引:5,他引:4
四株嗜盐菌Haloarcula vallismortis(EM201)、Haloferax denitrificans(EM303)、A_5和B_2已通过一对特定引物用PCR技术从总DNA中扩增出各自的16SrDNA片段,分子大小在1.47kd左右.DNA杂交也表明这些PCR产物具有嗜盐菌的同源性. 相似文献