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1.
In the search for the genome of egg drop syndrome virus (EDSV-76) Chinese strain AAV-2, part of restrietion endonuclease physical map is analyzed, the complete genomic library is organized. On basis of this, the eomplete genome nueleotide sequences (32 838 bp in length, including terminal structures) are determined. The data analysis shows: compared with the other Adenoviruses, strain AAV-2 has more disparity on ganomic structure and the distribution of open reading frame (ORF). There are no elear E1, E3 and F4 regions in AAV-2 genome. Two segments located at both ends of genome (1.1 kb and 8.3 kb in length respectively) have no homology with the other adenovirus genomes. In addition, strain AAV-2 genome lacks ORFs encoding E1A, pⅤ and pⅨ, which are common ORFs encoding early, lately proteins in Adenovirus. This reveals differences between EDSA-76, the sole standard strain of group Ⅲ Avian Adenoviruses, and the other Avian Adenoviruses for the first time. It will help the search for Avian Adenovirus  相似文献   

2.
猪Ⅱ型圆环病毒豫A株的全基因组克隆与序列分析   总被引:13,自引:0,他引:13  
参照国外发表的猪Ⅱ型圆环病毒(porcine circovirus type 2,PCV-2)全基因组序列,设计一对PCV-2特异性引物,用该室分离的PCV-2豫A株感染PK-15细胞,从中提取PCV-2复制型基因组DNA,并以之为模板进行PCR扩增.回收PCR产物,构建重组测序质粒T-PCV-2.测序结果表明,猪Ⅱ型圆环病毒豫A株的全基因组为1767bp,与GenBank收录的PCV-2国外分离株核苷酸的同源性可高达97%.序列分析表明,复制型豫A株的基因组包含10个读码框架,其中ORF1、ORF2是其两个最主要的读码框架,分别编码314、234个氨基酸.豫A株和PCV-1间的ORF1、ORF2的氨基酸序列同源性分别为85%、66%,与其它PCV-2毒株间的ORF1氨基酸同源性均在98%以上,而ORF2的氨基酸同源性为92%~97%.  相似文献   

3.
The complete genomic sequence of an aerobic thermoacidophilic crenarchaeon, Sulfolobus tokodaii strain7 which optimally grows at 80 degrees C, at low pH, and under aerobic conditions, has been determined by the whole genome shotgun method with slight modifications. The genomic size was 2,694,756 bp long and the G + C content was 32.8%. The following RNA-coding genes were identified: a single 16S-23S rRNA cluster, one 5S rRNA gene and 46 tRNA genes (including 24 intron-containing tRNA genes). The repetitive sequences identified were SR-type repetitive sequences, long dispersed-type repetitive sequences and Tn-like repetitive elements. The genome contained 2826 potential protein-coding regions (open reading frames, ORFs). By similarity search against public databases, 911 (32.2%) ORFs were related to functional assigned genes, 921 (32.6%) were related to conserved ORFs of unknown function, 145 (5.1%) contained some motifs, and remaining 849 (30.0%) did not show any significant similarity to the registered sequences. The ORFs with functional assignments included the candidate genes involved in sulfide metabolism, the TCA cycle and the respiratory chain. Sequence comparison provided evidence suggesting the integration of plasmid, rearrangement of genomic structure, and duplication of genomic regions that may be responsible for the larger genomic size of the S. tokodaii strain7 genome. The genome contained eukaryote-type genes which were not identified in other archaea and lacked the CCA sequence in the tRNA genes. The result suggests that this strain is closer to eukaryotes among the archaea strains so far sequenced. The data presented in this paper are also available on the internet homepage (http://www.bio.nite.go.jp/E-home/genome_list-e.html/).  相似文献   

4.
The novel human papillomavirus type 199 (HPV199) was initially identified in a nasopharyngeal swab sample obtained from a 25 year-old immunocompetent male. The complete genome of HPV199 is 7,184 bp in length with a GC content of 36.5%. Comparative genomic characterization of HPV199 and its closest relatives showed the classical genomic organization of Gammapapillomaviruses (Gamma-PVs). HPV199 has seven major open reading frames (ORFs), encoding five early (E1, E2, E4, E6, and E7) and two late (L1 and L2) proteins, while lacking the E5 ORF. The long control region (LCR) of 513 bp is located between the L1 and E6 ORFs. Phylogenetic analysis additionally confirmed that HPV-199 clusters into the Gamma-PV genus, species Gamma-12, additionally containing HPV127, HV132, HPV148, HPV165, and three putative HPV types: KC5, CG2 and CG3. HPV199 is most closely related to HPV127 (nucleotide identity 77%). The complete viral genome sequence of additional HPV199 isolate was determined from anal canal swab sample. Two HPV199 complete viral sequences exhibit 99.4% nucleotide identity. To the best of our knowledge, this is the first member of Gamma-PV with complete nucleotide sequences determined from two independent clinical samples. To evaluate the tissue tropism of the novel HPV type, 916 clinical samples were tested using HPV199 type-specific real-time PCR: HPV199 was detected in 2/76 tissue samples of histologically confirmed common warts, 2/108 samples of eyebrow hair follicles, 2/137 anal canal swabs obtained from individuals with clinically evident anal pathology, 4/184 nasopharyngeal swabs and 3/411 cervical swabs obtained from women with normal cervical cytology. Although HPV199 was found in 1.4% of cutaneous and mucosal samples only, it exhibits dual tissue tropism. According to the results of our study and literature data, dual tropism of all Gamma-12 members is highly possible.  相似文献   

5.
目的:从大肠埃希氏杆菌UTI89基因组中筛选出全部潜在的分泌蛋白并进行初步研究。方法:使用SignalP3.0、TatP1.0、 SecretomeP2.0等蛋白分析软件对5211个ORF进行预测;对筛选出的信号肽及分泌蛋白的基本特征进行统计学分析;使用Blast 2 Sequences进行同源性分析。结果:共筛选出432个sec途径分泌蛋白,19个Tat途径分泌蛋白,386个非经典分泌蛋白;信号肽、分泌蛋白平均长度分别为25.5aa、282.8aa;信号肽中出现频率最高的3种氨基酸依次为L、A、S;仅有两个信号肽的氨基酸序列完全相同,相应的分泌蛋白高度同源。结论:大肠埃希氏杆菌UTI89基因组中有837个ORF可能编码分泌蛋白;分泌蛋白集中在500aa以下;组成信号肽的氨基酸相对保守,多数为疏水氨基酸;信号肽变异性较大,含相同信号肽的蛋白可能由同源基因编码。  相似文献   

6.
目的:建立甲基营养菌MP681基因组文库,用于鸟枪法测序。方法:提取MP681基因组DNA,经超声随机片段化及T4 DNA聚合酶末端修平处理后,与经SmaⅠ酶切、小牛肠碱性磷酸酶(CIP)去磷酸化处理的pUC19载体连接,电击转化大肠杆菌DH5α感受态,并通过末端双向测序对文库质量进行评价。结果:分别构建了2~4 kb和4~6 kb基因组文库,电泳结果显示插入片段长度与预期符合,文库库容均在10万以上。结论:构建了插入片段大小和库容符合要求的甲基营养菌MP681全基因组鸟枪法2~4 kb、4~6 kb测序文库。  相似文献   

7.
黑龙江省是肾综合征因热(HFRS)的重疫区。近年来HFRS年的发病人数曾超过万人。流行病学和血清学研究表明黑龙江省HFRS疫区主要是姬鼠型,但目前尚缺乏病毒的分子生物学资料。我们对从疫区捕获的宿主动物-黑线姬鼠肺中分离的汉坦病毒HTN261株的S基因片段的全基因序列进测定和初步分析。结果如下,HTN261株的S基因片段的全序列长为1697nt。只有一个主要的编码N蛋白的ORF,起始位置为第37nt,终止于1326nt,编码的蛋白长为429aa。没有发现存在ORF2。HTN261株的S基因片段核苷酸序列与HGTN型中的病毒株的同源性很高,而与汉坦病毒其他型的同源民生较差,从种系发生树分析来看,HNT261株归结于汉坦病毒的HTN型。在HTN型之内,HTN261株和HTN76-118株在一个分枝内,就其核苷酸和蛋白的同源性说,HT N261株和HTN76-118株的同源性分别是89%(全S基因)和98%(蛋白)。而与中国境内发现的其他汉坦病毒株Z10,HU,Chen4,NC167等基因和蛋白的同源性相对较差,汉坦病毒除具有其宿主的依赖性外,还具有其地理的簇集性。HTN261株和HTN76-118株之间S基因和N蛋白序列的变异性的差异分别为11%和2%,表明HTN261株和HTN76-118株还有不同,可能是不同的亚型。不过,尚有待于进一步研究证明。  相似文献   

8.
黑龙江省是肾综合征出血热(HFRS)的重疫区。近年来HFRS年的发病人数曾超过万人。流行病学和血清学研究表明黑龙江省HFRS疫区主要是姬鼠型,但目前尚缺乏病毒的分子生物学资料。我们对从疫区捕获的宿主动物-黑线姬鼠肺中分离的汉坦病毒HTN261株的S基因片段的全基因序列进行了测定和初步分析。结果如下,HTN261株的S基因片段的全序列长为1697nt。只有一个主要的编码N蛋白的ORF,起始位置为第37nt,终止于1326nt,编码的蛋白长为429aa。没有发现存在ORF2。HTN261株的S基因片段核苷酸序列与HTN型中的病毒株的同源性很高,而与汉坦病毒其他型的同源性较差。从种系发生树分析来看,HTN261株归结于汉坦病毒的HTN型。在HTN型之内,HTN261株和HTN76-118株在一个分枝内。就其核苷酸和蛋白的同源性来说,HTN261株和HTN76-118株的同源性分别是89%(全S基因)和98%(蛋白)。而与中国境内发现的其他汉坦病毒株Z10,HU,Chen4,NC167等基因和蛋白的同源性相对较差。汉坦病毒除具有其宿主的依赖性外,还具有其地理的簇集性。HTN261株和HTN76-118株之间S基因和N蛋白序列的变异性的差异分别为11%和2%,表明HTN261株和HTN76-118株还有不同,可能是不同的亚型。不过,尚有待于进一步研究证明。  相似文献   

9.
The genome sequences of Neisseria meningitidis serogroup B strain MC58 and serogroup A strain Z2491 were systematically searched for open reading frames (ORFs) encoding autotransporters. Eight ORFs were identified, six of which were present in both genomes, whereas two were specific for MC58. Among the identified ORFs was the gene encoding the known autotransporter IgA1 protease. The deduced amino acid sequences of the other identified ORFs were homologous to known autotransporters and found to contain an N-terminal signal sequence and a C-terminal domain that could constitute a beta-barrel in the outer membrane. The ORFs NMB1985 and NMB0992, encoding homologs of the Hap (for Haemophilus adhesion and penetration protein) and Hia (for Haemophilus influenzae adherence protein) autotransporters of H. influenzae, were cloned from serogroup B strain H44/76 and expressed in Escherichia coli. Western blots revealed that all sera of patients (n=14) and healthy carriers (n=3) tested contained antibodies against at least one of the recombinant proteins. These results indicate that both genes are widely distributed among N. meningitidis isolates and expressed during colonization and infection.  相似文献   

10.
X.-Q. Yu  H.-Y. Wang  Y.-F. Lan    X.-P. Zhu    X.-D. Li    Z.-F. Fan    H.-F. Li    Y.-Y. Wang 《Journal of Phytopathology》2008,156(6):346-351
The complete genomic sequence of a Chinese Potato virus X isolate FX21 (PVX‐FX21) was determined from three overlapping cDNA clones. The genome of PVX‐FX21 is 6435 nucleotides in length excluding the poly(A) tail and contains five open reading frames (ORFs). Its entire genomic sequence shares 95.2–96.3% identities with Asian and European isolates, and 77.3–77.8% with American isolates. Phylogenetic analysis of the complete genomic sequence reveals two groups: the Eurasian group and the American group. PVX‐FX21 belongs to the Eurasian group and forms a separate sub‐branch with three Asian isolates. Similar analyses of the coat protein genes of 37 PVX isolates also reveal two major groups. All PVX isolates from Asia are clustered to group I, whereas isolates from Europe and America are clustered to both groups. Nucleotide sequence diversity analyses show that there is no geographical differentiation between PVX isolates and that constraint on the ORF encoding RNA‐dependent RNA polymerase is much higher than those on the other four ORFs.  相似文献   

11.
Bahr U  Darai G 《Journal of virology》2001,75(10):4854-4870
The tupaia herpesvirus (THV) was isolated from spontaneously degenerating tissue cultures of malignant lymphoma, lung, and spleen cell cultures of tree shrews (Tupaia spp.). The determination of the complete nucleotide sequence of the THV strain 2 genome resulted in a 195,857-bp-long, linear DNA molecule with a G+C content of 66.5%. The terminal regions of the THV genome and the loci of conserved viral genes were found to be G+C richer. Furthermore, no large repetitive DNA sequences could be identified. This is in agreement with the previous classification of THV as the prototype species of herpesvirus genome group F. The search for potential coding regions resulted in the identification of 158 open reading frames (ORFs) regularly distributed on both DNA strands. Seventy-six out of the 158 ORFs code for proteins that are significantly homologous to known herpesvirus proteins. The highest homologies found were to primate and rodent cytomegaloviruses. Biological properties, protein homologies, the arrangement of conserved viral genes, and phylogenetic analysis revealed that THV is a member of the subfamily Betaherpesvirinae. The evolutionary lineages of THV and the cytomegaloviruses seem to have branched off from a common ancestor. In addition, it was found that the arrangements of conserved genes of THV and murine cytomegalovirus strain Smith, both of which are not able to form genomic isomers, are colinear with two different human cytomegalovirus (HCMV) strain AD169 genomic isomers that differ from each other in the orientation of the long unique region. The biological properties and the high degree of relatedness of THV to the mammalian cytomegaloviruses allow the consideration of THV as a model system for investigation of HCMV pathogenicity.  相似文献   

12.
The 38 kb eicosapentaenoic acid (EPA) biosynthesis gene cluster of Shewanella sp. strain SCRC-2738 was cloned into the cosmid vector (pEPA). A 27 kb nucleotide sequence of the XhoI to SpeI region of pEPA showed EPA production (6.3%) in E. coli JM109. Among the nine open reading frames (ORFs) in this sequence, only five (ORFs 2 and 5-8) were essential for EPA production. High levels of production (16%-22%) were found in E. coli JM109 transformed with a multicopy pNEB vector carrying only the five essential ORFs and in that transformed with a pNEB vector that integrated ORFs 3, 5, 6, 7 and 8, and vector pSTV28 that integrated the ORF2 encoding phosphopantetheinyl transferase (PPTase). Thus, production of EPA appears to be regulated by the presence of all the biosynthesis gene products and by the ratio of PPTase to the other gene products. The temperature -EPA production relationship in E. coli strain DH5alpha varied between constructs, suggesting that it is controlled not only by EPA biosynthesis enzymes but also by other factors in vivo. There was a strict upper temperature limit for EPA biosynthesis: no EPA was synthesized at 30 degrees C in E. coli transformants carrying any gene construct for EPA biosynthesis.  相似文献   

13.
Conservation efforts to prevent the extinction of the endangered western barred bandicoot (Perameles bougainville) are currently hindered by a progressively debilitating cutaneous and mucocutaneous papillomatosis and carcinomatosis syndrome observed in captive and wild populations. In this study, we detected a novel virus, designated the bandicoot papillomatosis carcinomatosis virus type 1 (BPCV1), in lesional tissue from affected western barred bandicoots using multiply primed rolling-circle amplification and PCR with the cutaneotropic papillomavirus primer pairs FAP59/FAP64 and AR-L1F8/AR-L1R9. Sequencing of the BPCV1 genome revealed a novel prototype virus exhibiting genomic properties of both the Papillomaviridae and the Polyomaviridae. Papillomaviral properties included a large genome size ( approximately 7.3 kb) and the presence of open reading frames (ORFs) encoding canonical L1 and L2 structural proteins. The genomic organization in which structural and nonstructural proteins were encoded on different strands of the double-stranded genome and the presence of ORFs encoding the nonstructural proteins large T and small t antigens were, on the other hand, typical polyomaviral features. BPCV1 may represent the first member of a novel virus family, descended from a common ancestor of the papillomaviruses and polyomaviruses recognized today. Alternatively, it may represent the product of ancient recombination between members of these two virus families. The discovery of this virus could have implications for the current taxonomic classification of Papillomaviridae and Polyomaviridae and can provide further insight into the evolution of these ancient virus families.  相似文献   

14.
Coronaviruses are enveloped, positive-stranded RNA viruses with a genome of approximately 30 kb. Based on genetic similarities, coronaviruses are classified into three groups. Two group 2 coronaviruses, human coronavirus OC43 (HCoV-OC43) and bovine coronavirus (BCoV), show remarkable antigenic and genetic similarities. In this study, we report the first complete genome sequence (30,738 nucleotides) of the prototype HCoV-OC43 strain (ATCC VR759). Complete genome and open reading frame (ORF) analyses were performed in comparison to the BCoV genome. In the region between the spike and membrane protein genes, a 290-nucleotide deletion is present, corresponding to the absence of BCoV ORFs ns4.9 and ns4.8. Nucleotide and amino acid similarity percentages were determined for the major HCoV-OC43 ORFs and for those of other group 2 coronaviruses. The highest degree of similarity is demonstrated between HCoV-OC43 and BCoV in all ORFs with the exception of the E gene. Molecular clock analysis of the spike gene sequences of BCoV and HCoV-OC43 suggests a relatively recent zoonotic transmission event and dates their most recent common ancestor to around 1890. An evolutionary rate in the order of 4 x 10(-4) nucleotide changes per site per year was estimated. This is the first animal-human zoonotic pair of coronaviruses that can be analyzed in order to gain insights into the processes of adaptation of a nonhuman coronavirus to a human host, which is important for understanding the interspecies transmission events that led to the origin of the severe acute respiratory syndrome outbreak.  相似文献   

15.
16.
The complete nucleotide sequence of the genomic RNA of odontoglossum ringspot virus Cy-1 strain (ORSV Cy-1) was determined using cloned cDNA. This sequence is 6611 nucleotides long containing four open reading frames, which correspond to 126 K, 183 K, 31 K, and 18 K proteins. Its genomic organization is similar to other tobamoviruses, TMV-V(vulgare), TMV-L (tomato strain), tobacco mild green mosaic virus (TMGMV) and cucumber green mottle mosaic virus (CGMMV). The 5′ non-coding regions of ORSV Cy-1 is 62 nucleotides. The ORFs encoded a 126 K polypeptide and a 183 K read-through product in which helicase-sequence and polymerase-sequence motifs are found. The ORFs encoding the 126 K and 183 K proteins have 61% and 63% identities with those of TMV-V. The third ORF encoded a 31 K protein homologous to TMV cell-to-cell movement protein. It has 63% identities with that of TMV-V. The fourth ORF encoded an 18 K coat protein. The 5′ non-coding region, which extends from base 1 to 62 has 2 G residues and a ribosome binding site (AUU). The 3′ non-coding region, 414 nucleotides in length, is entirely different from that of other tobamoviruses.  相似文献   

17.
A myovirus-like temperate phage, PhiHAP-1, was induced with mitomycin C from a Halomonas aquamarina strain isolated from surface waters in the Gulf of Mexico. The induced cultures produced significantly more virus-like particles (VLPs) (3.73 x 10(10) VLP ml(-1)) than control cultures (3.83 x 10(7) VLP ml(-1)) when observed with epifluorescence microscopy. The induced phage was sequenced by using linker-amplified shotgun libraries and contained a genome 39,245 nucleotides in length with a G+C content of 59%. The PhiHAP-1 genome contained 46 putative open reading frames (ORFs), with 76% sharing significant similarity (E value of <10(-3)) at the protein level with other sequences in GenBank. Putative functional gene assignments included small and large terminase subunits, capsid and tail genes, an N6-DNA adenine methyltransferase, and lysogeny-related genes. Although no integrase was found, the PhiHAP-1 genome contained ORFs similar to protelomerase and parA genes found in linear plasmid-like phages with telomeric ends. Southern probing and PCR analysis of host genomic, plasmid, and PhiHAP-1 DNA indicated a lack of integration of the prophage with the host chromosome and a difference in genome arrangement between the prophage and virion forms. The linear plasmid prophage form of PhiHAP-1 begins with the protelomerase gene, presumably due to the activity of the protelomerase, while the induced phage particle has a circularly permuted genome that begins with the terminase genes. The PhiHAP-1 genome shares synteny and gene similarity with coliphage N15 and vibriophages VP882 and VHML, suggesting an evolutionary heritage from an N15-like linear plasmid prophage ancestor.  相似文献   

18.
Whole genome phylogenetic analysis in this study resolved a total of five major genotypes among the 22 varicella-zoster virus (VZV) strains or isolates for which complete genomic sequences are available. Consistent with earlier publications we have designated these genotypes European 1 (E1), European 2 (E2), Japanese (J), mosaic 1 (M1), and mosaic 2 (M2). Single nucleotide polymorphism (SNP) analysis performed in a whole-genome alignment revealed that VZV isolates of all five genotypes can be accurately genotyped using SNPs from two amplicons: open reading frame 22 (ORF22) and either ORF21 or ORF50. This modified approach identifies all of the genotypes observed using any of the published genotyping protocols. Of 165 clinical varicella and zoster isolates from Australia and New Zealand typed using this approach, 67 of 127 eastern Australian isolates were E1, 30 were E2, 16 were J, 10 were M1, and 4 were M2; 25 of 38 New Zealand isolates were E1, 8 were E2, and 5 were M1. VZV strain diversity in eastern Australia is thus broader than has been described for any other region, including Europe, Africa, and North America. J strains were far more prevalent than previously observed in countries other than Japan. Two-amplicon typing was in complete accord with genotypes derived using SNP in multiple ORFs (ORFs 1, 21, 22, 38, 50, 54, and 62). Two additional minor genotypes, M3 and M4, could also be resolved using two-amplicon typing.  相似文献   

19.
Clostridial organisms produce neurotoxins, which are generally regarded as the most potent toxic substances of biological origin and potential biological warfare agents. Clostridium tetani produces tetanus neurotoxin and is responsible for the fatal tetanus disease. In spite of the extensive immunization regimen, the disease is an important cause of death especially among neonates. Strains of C. tetani have not been genetically characterized except the complete genome sequencing of strain E88. The present study reports the genetic makeup and phylogenetic affiliations of an environmental strain of this bacterium with respect to C. tetani E88 and other clostridia. A shot gun library was constructed from the genomic DNA of C. tetani drde, isolated from decaying fish sample. Unique clones were sequenced and sequences compared with its closest relative C. tetani E88.A total of 275 clones were obtained and 32,457 bases of non-redundant sequence were generated. A total of 150 base changes were observed over the entire length of sequence obtained, including, additions, deletions and base substitutions. Of the total 120 ORFs detected, 48 exhibited closest similarity to E88 proteins of which three are hypothetical proteins. Eight of the ORFs exhibited similarity with hypothetical proteins from other organisms and 10 aligned with other proteins from unrelated organisms. There is an overall conservation of protein sequences among the two strains of C. tetani and. Selected ORFs involved in cellular processes and metabolism were subjected to phylogenetic analysis.  相似文献   

20.
鸡减蛋综合征病毒(EDSV—76)基因组E1区结构特点分析   总被引:1,自引:0,他引:1  
金奇  李茂祥 《病毒学报》1998,14(3):253-256
EDSV-76病毒中国株AA-2经常规方法提取其病毒DNA后,建立了限制性内切酶PstI水解片段的全基因文库。对其中PstI-G片段和PstI-A片段的正反链进行序列测定,获得EDSV E1区(0-8.8m.u)的核苷酸序列。经分析,EDSV E1区具有与其他腺病毒E1区类似的结构。以大于60个氨基酸残基为标准,EDSV E1区共有7个开放读码框架(ORF),其中R1、R2、ElbsT和E1b1T  相似文献   

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