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Preliminary study on mitochondrial 16S rRNA gene sequences and phylogeny of flatfishes (Pleuronectiformes) 被引量:4
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作者 尤锋 刘静 +1 位作者 张培军 相建海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第3期335-339,共5页
A 605 bp section of mitochondrial 16S rRNA gene from Paralichthys olivaceus, Pseudorhombus cinnamomeus, Psetta maxima and Kareius bicoloratus, which represent 3 families of Order Pleuronectiformes was amplified by PCR... A 605 bp section of mitochondrial 16S rRNA gene from Paralichthys olivaceus, Pseudorhombus cinnamomeus, Psetta maxima and Kareius bicoloratus, which represent 3 families of Order Pleuronectiformes was amplified by PCR and sequenced to show the molecular systematics of Pleuronectiformes for comparison with related gene sequences of other 6 flatfish downloaded from GenBank. Phylogenetic analysis based on ge- netic distance from related gene sequences of 10 flatfish showed that this method was ideal to explore the rela- tionship between species, genera and families. Phylogenetic trees set-up is based on neighbor-joining, maximum parsimony and maximum likelihood methods that accords to the general rule of Pleuronectiformes evolution. But they also resulted in some confusion. Unlike data from morphological characters, P. olivaceus clustered with K. bicoloratus, but P. cinnamomeus did not cluster with P. olivaceus, which is worth further studying. 展开更多
关键词 比目鱼 线粒体 RNA 基因
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Isolation of Pectinase Producing Bacteria from the Rhizosphere of <i>Andrographis paniculata</i>Nees and 16S rRNA Gene Sequence Comparison of Some Potential Strains 被引量:2
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作者 Md. Shahinur Kabir Tahera Tasmim 《Advances in Microbiology》 2019年第1期1-13,共13页
Pectinases, the enzymes which break down pectic substances, have a wide range of applications in food, agriculture and environmental sectors. In the present study, attempts were made to isolate highly efficient pectin... Pectinases, the enzymes which break down pectic substances, have a wide range of applications in food, agriculture and environmental sectors. In the present study, attempts were made to isolate highly efficient pectinase producer from the rhizosphere of a medicinal plant, Andrographis paniculata Nees, known as the “King of bitters”. The total heterotrophic bacterial count of the rhizosphere soil of A. paniculata Nees ranged from 1.53 × 109 to 2.52 × 109 cfu/g. A total of 65 bacterial colonies were randomly selected from the nutrient agar plates, purified and assessed for pectinase activity. Out of the 65 isolates, 62 (95.38%) showed varying degree of pectinase activity in plate assay using pectin as a sole source of carbon. Among the pectinase producing strains, JBST36 showed best pectinase activity which is followed by the JBST22 and JBST27. Morphological characterization, biochemical tests and 16S rRNA gene sequencing were performed to identify the three most potential strains. Based on the morphological, biochemical and molecular data, JBST22 was identified as Bacillus flexus and the other two were identified as Bacillus subtilis. Furthermore, nucleotide sequences of the 16S rRNA gene of these 3 strains were compared and a phylogenetic tree was constructed. The study reveals that there are at least 66 base differences in the 16S rRNA gene sequences of B. flexus JBST22 and the B. subtilis JBST36. 展开更多
关键词 16S rRNA gene ANDROGRAPHIS paniculata PECTINASE RHIZOSPHERE
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Genetic Diversity in Populations of Sepiella maindroni Using 16S rRNA Gene Sequence Analysis 被引量:10
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作者 郑小东 WANG +6 位作者 Rucai Xiao Shu Yu Ruihai Yang Jianmin 《High Technology Letters》 EI CAS 2003年第1期1-5,共5页
Part of the 16S rRNA gene is amplified with PCR and sequenced for 5 populations of common Chinese cuttlefish Sepiella maindroni: three from the South China Sea, one from East China Sea and one from Japan. The result s... Part of the 16S rRNA gene is amplified with PCR and sequenced for 5 populations of common Chinese cuttlefish Sepiella maindroni: three from the South China Sea, one from East China Sea and one from Japan. The result shows that a total of 5 nucleotide positions are found to have gaps or insertions of base pairs among these individuals, and 13 positions are examined to be variable in all the sequences, which range from 494 to 509 base pairs. All of the individuals are grouped into 7 haplotypes (h1-h7). No marked genetic difference is observed among those populations. All of the individuals from Nagasaki belong to h1 and the h3 haplotype is found only in the coastal waters of China. AG transition in Nucleotide 255 is suggested to be taken as a kind of genetic marker to identify the populations distributed in East-South China Sea and the Nagasaki waters of Japan. 展开更多
关键词 墨鱼 遗传多样性 16SRRNA基因 序列分析 核苷
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Genetic Differentiation Analyses Based on mtDNA COⅡ Gene Sequences Among Different Geographic Populations of Aphis glycines(Hemiptera: Aphididae) in Northeast China 被引量:1
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作者 Li Ran Han Lan-lan +4 位作者 Ye Le-fu Zhang Hong-yu Sun Wen-peng Tong Xin Zhao Kui-jun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第3期23-31,共9页
Aphis glycines(Hemiptera: Aphididae) is considered as a cosmopolitan pest of cultivated soybean, major diffi culties in its control measures may be due to its higher genetic diversity; however, the knowledge about pop... Aphis glycines(Hemiptera: Aphididae) is considered as a cosmopolitan pest of cultivated soybean, major diffi culties in its control measures may be due to its higher genetic diversity; however, the knowledge about population genetic diversity of this species is limited. This study aimed to represent the genetic differentiation among different geographic populations of soybean aphid in Northeast China. In order to investigate and assess the genetic diversity, genetic differentiation, molecular variance, population structure, ecological importance and evolutionary history of A. glycines, we sequenced a fragment of one protein-coding gene, the cytochrome c oxidaseⅡof mitochondrial DNA gene. The results showed that four haplotypes were defi ned among COⅡ gene of 180 sequences of soybean aphid in Northeast China including H1 shared by all the populations. Lower haplotype diversity(Hd=0.3590±0.0420) and nucleotide diversity(Pi=0.0012±0.0002) were observed and high gene flow was detected in every two populations, while most of the variation(80.81%) arose from variability within A. glycines from individuals. Low genetic differentiation and high gene fl ow(Nm=2.106) indicated a high migration rate between the populations, which might reveal that gene flow in different geographic populations did not affect by geographical distance. The phylogenetic tree and the haplotype network of A. glycines were obtained based on sequences of COⅡ gene, there were no signifi cant genealogical branches or clusters recognized in NJ tree, and no clear distribution, delineation of haplotypes were demonstrated in the haplotype network according to geographical location. This study rejected the vicariance hypothesis: geographic isolation could be a barrier and it restricted A. glycines gene fl ow among 10 populations. 展开更多
关键词 Aphis glycines mtDNA COⅡ geographic population gene flow genetic differentiation
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Gene Sequence, Soluble Expression and Homologous Comparison of a D-Hydantoinase fromPseudomonas putida YZ-26 被引量:3
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作者 SHI Ya-wei ZHAO Li-xia +2 位作者 NIU Li-xi FENG Xia YUAN Jing-ming 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第5期552-557,共6页
A 1440bp open-reading frame encoding D-hydantoinase from Pseudomonas putida YZ-26 was cloned and sequenced(GenBank AY387829). The DNA fragment was inserted into %Nde% and BamHI sites of vector pET-3a, yielding a recom... A 1440bp open-reading frame encoding D-hydantoinase from Pseudomonas putida YZ-26 was cloned and sequenced(GenBank AY387829). The DNA fragment was inserted into %Nde% and BamHI sites of vector pET-3a, yielding a recombinant plasmid, pET-HDT. After being transferred into the host strain, the artificial strain, pET-HDT/E.coli BL21 can express the D-hydantoinase as the soluble form in the Lura-Bertani medium without addition of any inducers. The activity of the enzyme toward substrate DL-hydantoin can reach 3000—4000 IU per cells from one-liter bacterial culture incubated at 30 ℃ for 10—12 h. By the comparison of amino acid sequence homology, hydrophobic residues analysis and secondary structure prediction, it was found that D-hydantoinase reported herein is quite similar to that from Pseudomonas putdia CCRC12857, and alike to that from Pseudomonas putdia DSM84 or other bacteria. A rapid and efficient purification procedure of the enzyme was performed by a three-step procedure: ammonium sulfate fractionation, phenyl Sepharose hydrophobic interaction chromatography and Sephacryl S-200 gel filtration. The molecular mass of the monomeric enzyme is 52042 Da as determined by MALDI-TOF mass spectrometry. 展开更多
关键词 乙内酰脲 基因序列 可溶解性 同源性 假单胞菌 光谱分析
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Diversity of Microflora in Colonic Mucus from Severe Ulcerative Colitis Patients Analyzed by Terminal Restriction Fragment Length Polymorphism and Clone Libraries of Bacterial 16S rRNA Gene Sequences 被引量:1
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作者 I-Nung Huang Yuri Sato +8 位作者 Mitsuo Sakamoto Moriya Ohkuma Shinobu Ohnuma Takeshi Naitoh Chikashi Shibata Akira Horii Junko Nishimura Haruki Kitazawa Tadao Saito 《Advances in Microbiology》 2014年第13期857-870,共14页
Although the gut microflora is thought to be an essential factor in the development of ulcerative colitis (UC), the entire gut microflora occurring in UC remains unknown. Most studies use feces to represent the microf... Although the gut microflora is thought to be an essential factor in the development of ulcerative colitis (UC), the entire gut microflora occurring in UC remains unknown. Most studies use feces to represent the microflora distribution;however, here we analyzed the bacterial diversity in colonic mucus from UC patients receiving colectomy surgery and control patients. The diversity of microflora was investigated using a combination of terminal restriction fragment length polymorphism (T-RFLP) and clone library analyses of the 16S rRNA gene sequences. In the T-RFLP analysis, the number of terminal restriction fragments (T-RFs) decreased significantly in UC patients when compared to control samples. Also in the clone library analysis, the number of operational taxonomic units (OTU) and the Shannon diversity index were reduced significantly in UC patients. These molecular analyses reveal an overall dysbiosis in UC patients. No specific pathogen was found, and a strong negative correlation in relative abundance of bacterial populations was observed between the phyla Bacteroidetes and Firmicutes in the UC patients. This is the first report showing a significant correlation between these two phyla, which may be important characteristics in the pathogenesis of UC. 展开更多
关键词 ULCERATIVE Colitis MICROFLORA Terminal Restriction Fragment Length Polymorphism 16S rRNA gene CLONE Library
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Designing and Cloning of the Gene Sequence Encoding Silk Fibroin Amorphous Domain 被引量:1
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作者 黄海燕 田智芳 +2 位作者 裔洪根 杨云星 王建南 《Journal of Donghua University(English Edition)》 EI CAS 2012年第6期489-492,共4页
To provide materials used in investigating the relationship between amino acid compositions of silk-like protein, structure, and functions, especially the biological functions, the motif genes encoding the silk fibroi... To provide materials used in investigating the relationship between amino acid compositions of silk-like protein, structure, and functions, especially the biological functions, the motif genes encoding the silk fibroin amorphous domain, SGFGPVANGGSGEASSESDFGSSGFGPVANASSGEASSESDFAG(F) were designed and extended using a "head-to-tail" construction strategy. The designed genes were cloned into PSLFA1180FA and multimerized to form structures containing a two-timer, a four-timer, an eight-timer, and a twelve-timer. All the resulting plasmids were digested using the restriction enzyme BamHI and the double-enzymes BglII/HindIII. Restriction enzyme analysis and DNA sequencing revealed the motif was successfully cloned into PSLFA1180FA and multimerized to form a twelve-timer without gene deletion or mutation. 展开更多
关键词 Escherichia coli silk fibroin amorphous domain gene cloning DNA electrophoresis
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Alloy Gene Sequence Project and System Science Philosophy
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作者 Youqing Xie Xiaobo Li +2 位作者 Xinbi Liu Hongjian Peng Yaozhuang Nie 《International Journal of Communications, Network and System Sciences》 2017年第12期327-401,共75页
System Science Philosophy is a knowledge system constructed of universal principle and law sequences. Alloy gene is a characteristic atom existing in the center of coordination cluster and occupying the lattice point ... System Science Philosophy is a knowledge system constructed of universal principle and law sequences. Alloy gene is a characteristic atom existing in the center of coordination cluster and occupying the lattice point of a lattice cell, and carries holographic information about valence electron structure, physical and thermodynamic properties obtained by alloy gene theory. Alloy gene potential energy curve function has developed traditional atom pair interaction potential functions into many atoms’ interaction function associated with valence electron structure, bond length, bond energy, which makes alloy gene Gibbs energy function can be established. Alloy gene Gibbs energy transmissive function has developed traditional partition function. Its equilibrium and sub-equilibrium transmissive modes produce alloy holographic network positioning bank, which is operable platform to achieve transformation from “trial and error” method to the “whole obtained from a few part” law for getting advanced alloys. It has become possible to launch alloy gene sequence project. 展开更多
关键词 ALLOY gene sequence System Science PHILOSOPHY ALLOY gene Theory ALLOY gene Gibbs Energy Transmissive Function ALLOY HOLOGRAPHIC Network Positioning BANK
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Phylogenetic Position of North Sulawesi <i>Tarsius sp</i>. Based on Partial Cytochrome b Gene Sequences
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作者 Decky David Wemvrid Kamagi Aloysius Duran Corebima Mariana Rengkuan 《Open Journal of Genetics》 2014年第4期332-341,共10页
Cyt b gene of North Sulawesi Tarsius sp., T. tumpara, T. sangirensis and T. tarsier (T. spectrum) had been partially sequenced. The homologous sequence of three groups had been compared to describe the phylogenetic po... Cyt b gene of North Sulawesi Tarsius sp., T. tumpara, T. sangirensis and T. tarsier (T. spectrum) had been partially sequenced. The homologous sequence of three groups had been compared to describe the phylogenetic position among them, as well as several other species accessed from the Genbank. Total DNA extracted from the muscular tissue had been obtained through tail cut sampling using the innuPREP DNA micro kit, and amplified using a pair of universal primer, L14841 and H15149. The size of the cyt b gene sequence amplified was 307 bp long. Sequence aligned using CLUSTAL-X program and diversity analysis were done using version 5.2.2. MEGA5 program. Genetic distance had been calculated by Tamura 3 parameter method and phylogenetic tree had been built using Neighbor-Joining and Maximum Likelihood methods. Genetic distance based on cyt b gene nucleotide was found from 0 to 0.240 with an average of 0.080. The phylogenetic tree constructed by Neighbor Joining and Maximum Likelihood methods indicated that T. tarsier, T. sangirensis and T. tumpara were closely related with Tarsius tarsier-complex, and distantly related with Cephalopachus bancanus and Carlito syrichta. The genetic distance and the phylogenetic tree had been constructed on the base of partial cyt b gene sequence of T. tarsier, T. sangirensis, T. tumpara and 5 other tarsier species and their accession. Those results are consistent with taxonomy based on morphology and vocal acoustic form. 展开更多
关键词 Molecular Phylogeny Tarsius sp. SULAWESI CYT b gene PARTIAL sequence
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Genetic Diversity of Chinese Soybean mosaic virus Strains and Their Relationships with Other Plant Potyviruses Based on P3 Gene Sequences 被引量:1
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作者 YANG Qing-hua LI Kai +1 位作者 ZHI Hai-jian GAI Jun-yi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第10期2184-2195,共12页
Soybean mosaic virus(SMV), a member of the genus Potyvirus, is a major pathogen of soybean plants in China, and 16 SMV strains have been identified nationwide based on a former detailed SMV classification system. As t... Soybean mosaic virus(SMV), a member of the genus Potyvirus, is a major pathogen of soybean plants in China, and 16 SMV strains have been identified nationwide based on a former detailed SMV classification system. As the P3 gene is thought to be involved in viral replication, systemic infection, pathogenicity, and overcoming resistance, knowledge of the P3 gene sequences of SMV and other potyviruses would be useful in efforts to know the genetic relationships among them and control the disease. P3 gene sequences were obtained from representative isolates of the above-mentioned 16 SMV strains and were compared with other SMV strains and 16 Potyvirus species from the National Center for Biotechnology GenBank database. The P3 genes from the 16 SMV isolates are composed of 1 041 nucleotides, encoding 347 amino acids, and share 90.7-100% nucleotide(NT) sequence identities and 95.1-100% amino acid(AA) sequence identities. The P3 coding regions of the 16 SMV isolates share high identities(92.4-98.9% NT and 96.0-100% AA) with the reported Korean isolates, followed by the USA isolates(88.5-97.9% NT and 91.4-98.6% AA), and share low identities(80.5-85.2% NT and 82.1-84.7% AA) with the reported HZ1 and P isolates from Pinellia ternata. The sequence identities of the P3 genes between SMV and the 16 potyviruses varied from 44.4 to 81.9% in the NT sequences and from 21.4 to 85.3% in the AA sequences, respectively. Among them, SMV was closely related to Watermelon mosaic virus(WMV), with 76.0-81.9% NT and 77.5-85.3% AA identities. In addition, the SMV isolates and potyvirus species were clustered into six distinct groups. All the SMV strains isolated from soybean were clustered in Group I, and the remaining species were clustered in other groups. A multiple sequence alignment analysis of the C-terminal regions indicated that the P3 genes within a species were highly conserved, whereas those among species were relatively variable. 展开更多
关键词 马铃薯Y病毒 大豆花叶病毒 基因序列 中国大豆 遗传多样性 植物 病毒株 GENBANK
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Paleogene Sequence Stratigraphy and Sea Level Change Cycles in South Xizang (Tibet) - Last Stage in Eastern Neo-Tethyan Evolution
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作者 Shi Xiaoying Wan Xiaoqiao Jia Caiping (Department of Geology and Mineral Resources, China University of Geosciences, Beijing 100083) 《Journal of Earth Science》 SCIE CAS CSCD 1996年第1期122-131,共10页
The marine Paleogene at Gangba, south Tibet is characterized by shallow water deposits and in vertical succession shows a clear facies change from fluvial plain through carbonate platform to retro-platform mud flat. F... The marine Paleogene at Gangba, south Tibet is characterized by shallow water deposits and in vertical succession shows a clear facies change from fluvial plain through carbonate platform to retro-platform mud flat. From the bottom of Danian to Upper Priabonian, nine 3rd -order depositional sequences are recognized, which in turn make up four supersequences and constitute two clear transgression-regression cycles. These requences were developed in a tectonic setting of strong compression resulted from the collision between the Indian and Eurasian plates. Between the Paleocene and Eocene, there exists an important hiatus that has consumed at least 5.5 Ma of deposition. This unconformity is thought to be created by the basement uplift coupled with eustatic fall and marks the basin transformation from epicontinental sea to remnant hay. The rapid basement subsidence and relative sea level rise in Late Eocene are thought to be caused by the loading flexure of the Eurasian continent onto the Indian plate, which resulted in the southward migration of depocenter in the epoch. 展开更多
关键词 PALEOgene sequence sea level cycle TECTONIC evolution SOUTH Tibet.
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Fuzzy Cluster Analysis of Alzheimer’s Disease-Related Gene Sequences
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作者 Jing Yang Jiarui Si +1 位作者 Xiaoxuan Gu Ouyan Shi 《Engineering(科研)》 2013年第10期530-533,共4页
The objective of this paper is to analyze the relationship among the interrelated gene sequences of Alzheimer’s disease (AD). Further this paper will provide a study on genetic factor of the occurrence about Alzheime... The objective of this paper is to analyze the relationship among the interrelated gene sequences of Alzheimer’s disease (AD). Further this paper will provide a study on genetic factor of the occurrence about Alzheimer’s disease, so as to provide more information on the prevention of Alzheimer’s disease, the clinical diagnosis and gene therapy for Alzheimer’s disease. The respective alignment of the Alzheimer’s disease interrelated gene sequences with those in The National Center for Biotechnology Information (NCBI) database was studied, and the measurement relationship of these sequences was identified and analyzed by the method of fuzzy cluster. The result of fuzzy cluster analysis indicates that the gene sequences interrelated within one group is consistently having closer relationship within the group other than in another group. 展开更多
关键词 Alzheimer’s Disease gene mRNA sequence ALIGNMENT Fuzzy CLUSTER
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Isolation of Three Strains of Avian Leukosis Virus Subgroup J and gp85 Gene Sequence Analysis
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作者 LIU Li-na LUO Qing-ping +5 位作者 CHENG Guo-fu HU Xue-ying YANG Jun ZHANG Lin SHAO Hua-bin LI Shao-wen 《Animal Husbandry and Feed Science》 CAS 2013年第1期11-13,52,共4页
[Objective] To isolate three strains of avian leukosis virus subgroup J(ALV-J) , and then amplify and sequence the gp85 gene. [Method] Three strains of ALV-J were isolated from Hubei Province, which were identified by... [Objective] To isolate three strains of avian leukosis virus subgroup J(ALV-J) , and then amplify and sequence the gp85 gene. [Method] Three strains of ALV-J were isolated from Hubei Province, which were identified by pathological anatomy, DF-1 cell culture and RT-PCR. And then they were named HB1002, HB1003 and HB1009, respectively.[Result] Test sequence analysis showed: the length of gp85 gene was 921 bp, consistent with expect result; the nucleotide homology between the three isolates was in 97.7%-99.7%,the homology of amino acid was in 95.1%-99%. The nucleotide homology between HPRS-103 and the three isolates was in the 94.1%-94.8%;and the nucleotide homology between other ALV-J and the three isolates was in 87.6%-97.3%.The phylogenetic trees analysis showed that the homology of JS09GY6 virus and the three isolates was nearest, in 95.2%-97.3%.[Conclusion] In the test, the three strains of virus which were isolated were ALV-J. 展开更多
关键词 基因序列分析 J亚群禽白血病病毒 染料溶液 核苷酸同源性 禽白血病病毒J亚群 ALV-J GP85基因 系统进化树分析
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On four closely related hypotrichous ciliates(Protozoa,Ciliophora,Spirotrichea):molecular characters,interspecific relationships and phylogeny defined with multigene sequence information
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作者 GAO Feng YI Zhenzhen +2 位作者 CHEN Zigui AL-RASHEID Khaled A S SONG Weibo 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2010年第5期90-96,共7页
In order to clarify the phylogeny and relationships of the most confused hypotrichous ciliates,Holosticha-complex,four closely related holostichids(five populations),Holosticha bradburyae,H.diademata,Anteholosticha sp... In order to clarify the phylogeny and relationships of the most confused hypotrichous ciliates,Holosticha-complex,four closely related holostichids(five populations),Holosticha bradburyae,H.diademata,Anteholosticha sp.,and A.manca,were compared and analyzed using ITS2 secondary structures,ITS1-5.8S-ITS2 region and SSrRNA gene sequences.The ITS1-5.8S-ITS2 region sequences of these four species were first sequenced,and they shared sequence identities ranging from 68.0% to 90.1%,while two populations of Anteholosticha sp.differed in three nucleotides(sequence identity 99.8%).There were several minor differences among ITS2 secondary structures of these species,while two populations of Anteholosticha sp.had the identical secondary structure.Phylogenetic trees inferred from the ITS1-5.8S-ITS2 region sequences of stichotrichs using multiple algorithms(Neighbor-Joining,Maximum Parsimony and Bayesian) revealed similar topologies.The results show that:(1) Holosticha bradburyae and H.diademata firmly clustered together with strong bootstrap supports,forming a sister clade with Anteholosticha sp.,(2) Anteholosticha appeared to be a paraphyletic assemblage,in which the morphotype A.manca was more closely related to Diaxonella trimarginata than to its congener Anteholosticha sp.Phylogenetic analyses based on the SSrRNA gene and the combined sequences of SSrRNA gene and ITS1-5.8S-ITS2 region revealed the similar relationships between Holosticha and Anteholosticha,nevertheless their positions within the subclass Stichotrichia differed from each other inferred from different genes. 展开更多
关键词 系统发育分析 腹毛类纤毛虫 序列信息 多基因 原生动物 分子特征 种间关系 RRNA基因序列
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Morphological observation and rbcL gene sequences studies of two new species,Grateloupia dalianensis H.W.Wang et D.Zhao,sp.nov.and G.yinggehaiensis H.W.Wang et R.X.Luan,sp.nov.(Halymeniaceae,Rhodophyta) from China 被引量:20
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作者 ZHAO Dan WANG Hongwei +2 位作者 SHENG Yingwen LV Jianzhou LUAN Rixiao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第2期109-120,共12页
A few species in the genus Grateloupia (Halymeniaceae,Rhodophyta) have been investigated in detail with respect to morphological observations and molecular analyses.In this study,the authors document the vegetative an... A few species in the genus Grateloupia (Halymeniaceae,Rhodophyta) have been investigated in detail with respect to morphological observations and molecular analyses.In this study,the authors document the vegetative and reproductive structures of two new species of Grateloupia,G.dalianensis H.W.Wang et D.Zhao,sp.nov.and G.yinggehaiensis H.W.Wang et R.X.Luan,sp.nov.They both have the morphological character that carpogonial ampullae and auxiliary cell ampullae are the simple Grateloupia-type.The two species can be distinguished from other species of the genus by their distinctive morphological features respectively.Based on ribulose-1,5-bisphosphate carboxylase/oxygenase (rbcL) gene sequences,the phylogenetic tree obtained in the study indicated that they are both embedded within the Grateloupia clade.G.dalianensis clusters a subclade with G.asiatica,and G.yinggehaiensis forms a single monophyletic subclade with G.hawaiiana. 展开更多
关键词 rbcL基因 基因序列 形态学观察 繁枝 SP 红藻 新品种 中国
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Characterizations of Chinese isolates of Coxiella burnetii in the com1 gene sequence
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作者 余全 张国全 《Journal of Medical Colleges of PLA(China)》 CAS 2002年第2期116-119,共4页
Objective: To know some genetical characterizations of Coxiella burnetii Chinese isolates by comparing the coml gene sequence. Methods: com1 gene sequences of Chinese isolates were amplified, se-quenced, and analyzed ... Objective: To know some genetical characterizations of Coxiella burnetii Chinese isolates by comparing the coml gene sequence. Methods: com1 gene sequences of Chinese isolates were amplified, se-quenced, and analyzed by comparing our result and the previous published data. Results: Three different com1 sequences were identified in 7 Chinese isolates. Sequence comparison indicated that the isolates harboring the QpRS plasmid could be defined as a new group and, in addition, the isolates carrying the same plas-mid type showed similar com1 gene sequence. Conclusion: Study suggests that the classification of the group based on the coml gene sequence is highly associated with the plasmid type of the isolates and, however, little related to disease forms and geographical origins of the isolates. 展开更多
关键词 伯纳特立克次体 Com1基因 序列分析
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Nematode Diversity of Qingdao Coast Inferred from the 18S Ribosomal RNA Gene Sequence Analysis 被引量:3
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作者 SHEN Xiquan YANG Guanpin LIU Yongjian 《Journal of Ocean University of China》 SCIE CAS 2007年第2期132-136,共5页
The 18S ribosomal DNA gene (18S rDNA) sequences (approximately 1300 bp in length) were amplified from the DNA extracted from the free-living marine nematodes collected from the inter-tidal sediment of Qingdao coast in... The 18S ribosomal DNA gene (18S rDNA) sequences (approximately 1300 bp in length) were amplified from the DNA extracted from the free-living marine nematodes collected from the inter-tidal sediment of Qingdao coast in bulk with nematode spe- cific primers. The PCR products were cloned, re-amplified, digested with Rsa I and Hin6 I restriction endonucleases and separated in agarose gel. Among 17 restriction fragment length types, types 1, 2 and 6 covered 61.2%, 14.4% and 9.3% of the clones analyzed, respectively, while the remaining 14 only covered 21 clones, which accounted for 15.1% of the total. Twenty-four representative clones were sequenced and phylogenetically analyzed by referring to those currently available in RDP and GenBank databases. Al- though it was hard to assign these sequences to known species or genera due to the lack of the 18S rDNA sequence data of known marine free-living nematodes, the obtained sequences were assigned to the nematodes of Adenophorea. Among them, twelve se- quences were close to Pontonema vulgare and Adoncholaimus sp., four to Daptonema procerus and two (identical) to Enoplus brevis. Our results showed that free-living marine nematode diversities could be determined by PCR retrieving and analysis of the 18S rDNA sequences and an 18S rDNA sequence could be assigned to a species or a genus only if the 18S rDNA sequences of the free-living marine nematodes were accumulated to some extent. 展开更多
关键词 青岛海滨 线虫类 生物多样性 18S核醣体RNA 基因序列分析
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Molecular phylogeny and species separation of five morphologically similar Holosticha-complex ciliates(Protozoa, Ciliophora) using ARDRA riboprinting and multigene sequence data 被引量:3
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作者 高凤 伊珍珍 +2 位作者 龚骏 Al-RASHEID Khaled A. S. 宋微波 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第3期542-548,共7页
To separate and redefine the ambiguous Holosticha-complex, a confusing group of hypotrichous ciliates, six strains belonging to five morphospecies of three genera, Holosticha heterofoissneri, Anteholosticha sp. pop1, ... To separate and redefine the ambiguous Holosticha-complex, a confusing group of hypotrichous ciliates, six strains belonging to five morphospecies of three genera, Holosticha heterofoissneri, Anteholosticha sp. pop1, Anteholosticha sp. pop2, A. manca, A. gracilis and Nothoholosticha fasciola, were analyzed using 12 restriction enzymes on the basis of amplified ribosomal DNA restriction analysis. Nine of the 12 enzymes could digest the DNA products, four (Hinf I, Hind III, Msp I, Taq I) yielded species-specific restriction patterns, and Hind III and Taq I produced different patterns for two Anteholosticha sp. populations. Distinctly different restriction digestion haplotypes and similarity indices can be used to separate the species. The secondary structures of the five species were predicted based on the ITS2 transcripts and there were several minor differences among species, while two Anteholosticha sp. populations were identical. In addition, phylogenies based on the SSrRNA gene sequences were reconstructed using multiple algorithms, which grouped them generally into four clades, and exhibited that the genus Anteholosticha should be a convergent assemblage. The fact that Holosticha species clustered with the oligotrichs and choreotrichs, though with very low support values, indicated that the topology may be very divergent and unreliable when the number of sequence data used in the analyses is too low. 展开更多
关键词 分子系统发育 数据分离 基因序列 纤毛虫 原生动物 形态 纤毛门 核糖体DNA
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Genetic Variation Among the Geographic Population of the Grain Aphid, Sitobion avenae (Hemiptera: Aphididae) in China Inferred from Mitochondrial COI Gene Sequence 被引量:7
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作者 XU Zhao-huan CHEN Ju-lian +2 位作者 CHENG Deng-fa LIU Yong Frédéric Francis 《Agricultural Sciences in China》 CAS CSCD 2011年第7期1041-1048,共8页
In order to characterize the genetic relationship of the geographic populations of Sitobion avenae (Hemiptera: Aphididae) in China, a 588 bp region of the mitochondrial cytochrome oxidase subunit I (mtDNA-COI) gene wa... In order to characterize the genetic relationship of the geographic populations of Sitobion avenae (Hemiptera: Aphididae) in China, a 588 bp region of the mitochondrial cytochrome oxidase subunit I (mtDNA-COI) gene was sequenced and analyzed among the different geographic populations. 269 individuals were collected from 17 localities in different wheat-growing areas in China that covered most of the range reported for this species. Within the sequence among these geographic populations, 15 polymorphic sites defined 16 distinct haplotypes, ranging in sequence divergence from 0.2% (one nucleotide) to 1.7% (10 nucleotides). Of the 15 variable sites, 12 were transitional substitutions, 2 were transversional substitutions and 1 was transitional and transversional substitution. Phylogenetic analysis showed that all haplotypes were highly interconnected with each other, in absence of phylogeographic structing. Each of 8 haplotypes was found only at one locality, and the other haplotypes were the widespread distributed in the different localities. The higher genetic diversity was found in the northern China populations than that in the southern China populations. The low genetic differentiation (FST=-0.06945-0.69857) and high migration rate (Nm=0.21575-infinite) of Chinese populations suggest that dispersal over long distance is a major factor in the demography of S. avenae. 展开更多
关键词 中国北方 地理种群 基因序列 遗传变异 麦长管蚜 线粒体 半翅目 细胞色素氧化酶
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Phylogeny of Limenitidinae Butterflies (Lepidoptera: Nymphalidae) Inferred from Mitochondrial Cytochrome Oxidase I Gene Sequences 被引量:2
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作者 ZHANG Min CAO Tian-wen +2 位作者 ZHONG Yang GUO Ya-ping MA En-bo 《Agricultural Sciences in China》 CAS CSCD 2011年第4期566-575,共10页
The phylogenetic analyses of the subfamily Limenitidinae are performed based on 1 471 bp of mtDNA cytochrome oxidase subunit I (COI) gene sequence data which were obtained from 21 individuals spanning 9 genera, along ... The phylogenetic analyses of the subfamily Limenitidinae are performed based on 1 471 bp of mtDNA cytochrome oxidase subunit I (COI) gene sequence data which were obtained from 21 individuals spanning 9 genera, along with those of 17 species obtained from GenBank, using Apatura iris, Aglais urticae, and Polyura dolon as outgroup species. Although the transitions at the third codon positions of the COI data set were highly saturated, they were still retained for analysis as they contain the majority of the phylogenetic information, and thus, the maximum pasimony (MP) under different weighting schemes and maximum likelihood (ML) trees were reconstructed in this study. The results showed that within this subfamily, the results based on the COI gene sequences are approximately identical to the traditional classification results. However, the clustering of Lexias pardalis and Tanaecia julii within the genus Euthalia as well as the clustering of Phaedyma aspasia within the genus Neptis with weak support are different from that of the current classification scheme made by Chinese scholars. The genus Limenitis is splited into two subclusters in the trees constructed by using MP and ML methods. These results support one of the strongest hypotheses for the tribe relationships within Limenitidinae. 展开更多
关键词 细胞色素氧化酶 系统发育分析 基因序列 线粒体 蛱蝶科 鳞翅目 GENBANK 蝴蝶
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