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Sample records for array-based comparative genomic

  1. Array-based comparative genomic hybridization for genome-wide screening of DNA copy number in bladder tumors.

    NARCIS (Netherlands)

    Veltman, J.A.; Fridlyand, J.; Pejavar, S.; Olshen, A.B.; Korkola, J.E.; Vries, S. de; Carroll, P.; Kuo, W.L.; Pinkel, D.; Albertson, D.; Cordon-Cardo, C.; Jain, A.N.; Waldman, F.M.

    2003-01-01

    Genome-wide copy number profiles were characterized in 41 primary bladder tumors using array-based comparative genomic hybridization (array CGH). In addition to previously identified alterations in large chromosomal regions, alterations were identified in many small genomic regions, some with high-l

  2. Genomic profiling of oral squamous cell carcinoma by array-based comparative genomic hybridization.

    Directory of Open Access Journals (Sweden)

    Shunichi Yoshioka

    Full Text Available We designed a study to investigate genetic relationships between primary tumors of oral squamous cell carcinoma (OSCC and their lymph node metastases, and to identify genomic copy number aberrations (CNAs related to lymph node metastasis. For this purpose, we collected a total of 42 tumor samples from 25 patients and analyzed their genomic profiles by array-based comparative genomic hybridization. We then compared the genetic profiles of metastatic primary tumors (MPTs with their paired lymph node metastases (LNMs, and also those of LNMs with non-metastatic primary tumors (NMPTs. Firstly, we found that although there were some distinctive differences in the patterns of genomic profiles between MPTs and their paired LNMs, the paired samples shared similar genomic aberration patterns in each case. Unsupervised hierarchical clustering analysis grouped together 12 of the 15 MPT-LNM pairs. Furthermore, similarity scores between paired samples were significantly higher than those between non-paired samples. These results suggested that MPTs and their paired LNMs are composed predominantly of genetically clonal tumor cells, while minor populations with different CNAs may also exist in metastatic OSCCs. Secondly, to identify CNAs related to lymph node metastasis, we compared CNAs between grouped samples of MPTs and LNMs, but were unable to find any CNAs that were more common in LNMs. Finally, we hypothesized that subpopulations carrying metastasis-related CNAs might be present in both the MPT and LNM. Accordingly, we compared CNAs between NMPTs and LNMs, and found that gains of 7p, 8q and 17q were more common in the latter than in the former, suggesting that these CNAs may be involved in lymph node metastasis of OSCC. In conclusion, our data suggest that in OSCCs showing metastasis, the primary and metastatic tumors share similar genomic profiles, and that cells in the primary tumor may tend to metastasize after acquiring metastasis-associated CNAs.

  3. 1-Mb resolution array-based comparative genomic hybridization using a BAC clone set optimized for cancer gene analysis

    NARCIS (Netherlands)

    Greshock, J; Naylor, TL; Margolin, A; Diskin, S; Cleaver, SH; Futreal, PA; deJong, PJ; Zhao, SY; Liebman, M; Weber, BL

    2004-01-01

    Array-based comparative genomic hybridization (aCGH) is a recently developed tool for genome-wide determination of DNA copy number alterations. This technology has tremendous potential for disease-gene discovery in cancer and developmental disorders as well as numerous other applications. However, w

  4. Using Array-Based Comparative Genomic Hybridization to Diagnose Pallister-Killian Syndrome.

    Science.gov (United States)

    Lee, Mi Na; Lee, Jiwon; Yu, Hee Joon; Lee, Jeehun; Kim, Sun Hee

    2017-01-01

    Pallister-Killian syndrome (PKS) is a rare multisystem disorder characterized by isochromosome 12p and tissue-limited mosaic tetrasomy 12p. In this study, we diagnosed three pediatric patients who were suspicious of having PKS using array-based comparative genomic hybridization (array CGH) and FISH analyses performed on peripheral lymphocytes. Patients 1 and 2 presented with craniofacial dysmorphic features, hypotonia, and a developmental delay. Array CGH revealed two to three copies of 12p in patient 1 and three copies in patient 2. FISH analysis showed trisomy or tetrasomy 12p. Patient 3, who had clinical features comparable to those of patients 1 and 2, was diagnosed by using FISH analysis alone. Here, we report three patients with mosaic tetrasomy 12p. There have been only reported cases diagnosed by chromosome analysis and FISH analysis on skin fibroblast or amniotic fluid. To our knowledge, patient 1 was the first case diagnosed by using array CGH performed on peripheral lymphocytes in Korea.

  5. Stochastic segmentation models for array-based comparative genomic hybridization data analysis.

    Science.gov (United States)

    Lai, Tze Leung; Xing, Haipeng; Zhang, Nancy

    2008-04-01

    Array-based comparative genomic hybridization (array-CGH) is a high throughput, high resolution technique for studying the genetics of cancer. Analysis of array-CGH data typically involves estimation of the underlying chromosome copy numbers from the log fluorescence ratios and segmenting the chromosome into regions with the same copy number at each location. We propose for the analysis of array-CGH data, a new stochastic segmentation model and an associated estimation procedure that has attractive statistical and computational properties. An important benefit of this Bayesian segmentation model is that it yields explicit formulas for posterior means, which can be used to estimate the signal directly without performing segmentation. Other quantities relating to the posterior distribution that are useful for providing confidence assessments of any given segmentation can also be estimated by using our method. We propose an approximation method whose computation time is linear in sequence length which makes our method practically applicable to the new higher density arrays. Simulation studies and applications to real array-CGH data illustrate the advantages of the proposed approach.

  6. Gene expression profiles in squamous cell cervical carcinoma using array-based comparative genomic hybridization analysis.

    Science.gov (United States)

    Choi, Y-W; Bae, S M; Kim, Y-W; Lee, H N; Kim, Y W; Park, T C; Ro, D Y; Shin, J C; Shin, S J; Seo, J-S; Ahn, W S

    2007-01-01

    Our aim was to identify novel genomic regions of interest and provide highly dynamic range information on correlation between squamous cell cervical carcinoma and its related gene expression patterns by a genome-wide array-based comparative genomic hybridization (array-CGH). We analyzed 15 cases of cervical cancer from KangNam St Mary's Hospital of the Catholic University of Korea. Microdissection assay was performed to obtain DNA samples from paraffin-embedded cervical tissues of cancer as well as of the adjacent normal tissues. The bacterial artificial chromosome (BAC) array used in this study consisted of 1440 human BACs and the space among the clones was 2.08 Mb. All the 15 cases of cervical cancer showed the differential changes of the cervical cancer-associated genetic alterations. The analysis limit of average gains and losses was 53%. A significant positive correlation was found in 8q24.3, 1p36.32, 3q27.1, 7p21.1, 11q13.1, and 3p14.2 changes through the cervical carcinogenesis. The regions of high level of gain were 1p36.33-1p36.32, 8q24.3, 16p13.3, 1p36.33, 3q27.1, and 7p21.1. And the regions of homozygous loss were 2q12.1, 22q11.21, 3p14.2, 6q24.3, 7p15.2, and 11q25. In the high level of gain regions, GSDMDC1, RECQL4, TP73, ABCF3, ALG3, HDAC9, ESRRA, and RPS6KA4 were significantly correlated with cervical cancer. The genes encoded by frequently lost clones were PTPRG, GRM7, ZDHHC3, EXOSC7, LRP1B, and NR3C2. Therefore, array-CGH analyses showed that specific genomic alterations were maintained in cervical cancer that were critical to the malignant phenotype and may give a chance to find out possible target genes present in the gained or lost clones.

  7. Comprehensive genome characterization of solitary fibrous tumors using high-resolution array-based comparative genomic hybridization.

    Science.gov (United States)

    Bertucci, François; Bouvier-Labit, Corinne; Finetti, Pascal; Adélaïde, José; Metellus, Philippe; Mokhtari, Karima; Decouvelaere, Anne-Valérie; Miquel, Catherine; Jouvet, Anne; Figarella-Branger, Dominique; Pedeutour, Florence; Chaffanet, Max; Birnbaum, Daniel

    2013-02-01

    Solitary fibrous tumors (SFTs) are rare spindle cell tumors with limited therapeutic options. Their molecular basis is poorly known. No consistent cytogenetic abnormality has been reported. We used high-resolution whole-genome array-based comparative genomic hybridization (Agilent 244K oligonucleotide chips) to profile 47 samples, meningeal in >75% of cases. Few copy number aberrations (CNAs) were observed. Sixty-eight percent of samples did not show any gene CNA after exclusion of probes located in regions with referenced copy number variation (CNV). Only low-level CNAs were observed. The genomic profiles were very homogeneous among samples. No molecular class was revealed by clustering of DNA copy numbers. All cases displayed a "simplex" profile. No recurrent CNA was identified. Imbalances occurring in >20%, such as the gain of 8p11.23-11.22 region, contained known CNVs. The 13q14.11-13q31.1 region (lost in 4% of cases) was the largest altered region and contained the lowest percentage of genes with referenced CNVs. A total of 425 genes without CNV showed copy number transition in at least one sample, but only but only 1 in at least 10% of samples. The genomic profiles of meningeal and extra-meningeal cases did not show any differences.

  8. Application of Array-Based Comparative Genomic Hybridization to Pediatric Neurologic Diseases

    OpenAIRE

    2013-01-01

    Purpose Array comparative genomic hybridization (array-CGH) is a technique used to analyze quantitative increase or decrease of chromosomes by competitive DNA hybridization of patients and controls. This study aimed to evaluate the benefits and yield of array-CGH in comparison with conventional karyotyping in pediatric neurology patients. Materials and Methods We included 87 patients from the pediatric neurology clinic with at least one of the following features: developmental delay, mental r...

  9. Genetic characterization of dogs via chromosomal analysis and array-based comparative genomic hybridization (aCGH).

    Science.gov (United States)

    Müller, M H; Reimann-Berg, N; Bullerdiek, J; Murua Escobar, H

    2012-01-01

    The results of cytogenetic and molecular cytogenetic investigations revealed similarities in genetic background and biological behaviour between tumours and genetic diseases of humans and dogs. These findings classify the dog a good and accepted model for human cancers such as osteosarcomas, mammary carcinomas, oral melanomas and others. With the appearance of new studies and advances in canine genome sequencing, the number of known homologies in diseases between these species raised and still is expected to increase. In this context, array-based comparative genomic hybridization (aCGH) provides a novel tool to rapidly characterize numerical aberrations in canine tumours or to detect copy number aberrations between different breeds. As it is possible to spot probes covering the whole genome on each chip to discover copy number aberrations of all chromosomes simultaneously, this method is time-saving and cost-effective - considering the relation of costs and the amount of data obtained. Complemented with traditional methods like karyotyping and fluorescence in situ hybridization (FISH) analyses, the aCGH is able to provide new insights into the underlying causes of canine carcinogenesis.

  10. Array-based comparative genomic hybridization is more informative than conventional karyotyping and fluorescence in situ hybridization in the analysis of first-trimester spontaneous abortion

    Directory of Open Access Journals (Sweden)

    Gao Jinsong

    2012-07-01

    Full Text Available Abstract Background Array-based comparative genomic hybridization (aCGH is a new technique for detecting submicroscopic deletions and duplications, and can overcome many of the limitations associated with classic cytogenetic analysis. However, its clinical use in spontaneous abortion needs comprehensive evaluation. We used aCGH to investigate chromosomal imbalances in 100 spontaneous abortions and compared the results with G-banding karyotyping and fluorescence in situ hybridization (FISH. Inconsistent results were verified by quantitative fluorescence PCR. Results Abnormalities were detected in 61 cases. aCGH achieved the highest detection rate (93.4%, 57/61 compared with traditional karyotyping (77%, 47/61 and FISH analysis (68.9%, 42/61. aCGH identified all chromosome abnormalities reported by traditional karyotyping and interphase FISH analysis, with the exception of four triploids. It also detected three additional aneuploidy cases in 37 specimens with ‘normal’ karyotypes, one mosaicism and 10 abnormalities in 14 specimens that failed to grow in vitro. Conclusions aCGH analysis circumvents many limitations in traditional karyotyping or FISH. The accuracy and efficiency of aCGH in spontaneous abortions highlights its clinical usefulness for the future. As aborted tissues have the potential to be contaminated with maternal cells, the threshold value of detection in aCGH should be lowered to avoid false negatives.

  11. Microalterations of inherently unstable genomic regions in rat mammary carcinomas as revealed by long oligonucleotide array-based comparative genomic hybridization

    NARCIS (Netherlands)

    Adamovic, T.; McAllister, D.; Guryev, V.; Wang, X.; Andrae, J.W.; Cuppen, E.; Jacob, H.; Sugg, S.L.

    2009-01-01

    The presence of copy number variants in normal genomes poses a challenge to identify small genuine somatic copy number changes in high-resolution cancer genome profiling studies due to the use of unpaired reference DNA. Another problem is the well-known rearrangements of immunoglobulin and T-cell re

  12. Microalterations of Inherently Unstable Genomic Regions in Rat Mammary Carcinomas as Revealed by Long Oligonucleotide Array-Based Comparative Genomic Hybridization

    NARCIS (Netherlands)

    Adamovic, Tatjana; McAllister, Donna; Guryev, Victor; Wang, Xujing; Andrae, Jaime Wendt; Cuppen, Edwin; Jacob, Howard J.; Sugg, Sonia L.

    2009-01-01

    The presence of copy number variants in normal genomes poses a challenge to identify small genuine somatic copy number changes in high-resolution cancer genome profiling studies due to the use of unpaired reference DNA. Another problem is the well-known rearrangements of immunoglobulin and T-cell re

  13. Array-based comparative genomic hybridization analysis reveals chromosomal copy number aberrations associated with clinical outcome in canine diffuse large B-cell lymphoma.

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    Arianna Aricò

    Full Text Available Canine Diffuse Large B-cell Lymphoma (cDLBCL is an aggressive cancer with variable clinical response. Despite recent attempts by gene expression profiling to identify the dog as a potential animal model for human DLBCL, this tumor remains biologically heterogeneous with no prognostic biomarkers to predict prognosis. The aim of this work was to identify copy number aberrations (CNAs by high-resolution array comparative genomic hybridization (aCGH in 12 dogs with newly diagnosed DLBCL. In a subset of these dogs, the genetic profiles at the end of therapy and at relapse were also assessed. In primary DLBCLs, 90 different genomic imbalances were counted, consisting of 46 gains and 44 losses. Two gains in chr13 were significantly correlated with clinical stage. In addition, specific regions of gains and losses were significantly associated to duration of remission. In primary DLBCLs, individual variability was found, however 14 recurrent CNAs (>30% were identified. Losses involving IGK, IGL and IGH were always found, and gains along the length of chr13 and chr31 were often observed (>41%. In these segments, MYC, LDHB, HSF1, KIT and PDGFRα are annotated. At the end of therapy, dogs in remission showed four new CNAs, whereas three new CNAs were observed in dogs at relapse compared with the previous profiles. One ex novo CNA, involving TCR, was present in dogs in remission after therapy, possibly induced by the autologous vaccine. Overall, aCGH identified small CNAs associated with outcome, which, along with future expression studies, may reveal target genes relevant to cDLBCL.

  14. Array-based comparative genomic hybridization facilitates identification of breakpoints of a novel der(1)t(1;18)(p36.3;q23)dn in a child presenting with mental retardation.

    Science.gov (United States)

    Lennon, P A; Cooper, M L; Curtis, M A; Lim, C; Ou, Z; Patel, A; Cheung, S W; Bacino, C A

    2006-06-01

    Monosomy of distal 1p36 represents the most common terminal deletion in humans and results in one of the most frequently diagnosed mental retardation syndromes. This deletion is considered a contiguous gene deletion syndrome, and has been shown to vary in deletion sizes that contribute to the spectrum of phenotypic anomalies seen in patients with monosomy 1p36. We report on an 8-year-old female with characteristics of the monosomy 1p36 syndrome who demonstrated a novel der(1)t(1;18)(p36.3;q23). Initial G-banded karyotype analysis revealed a deleted chromosome 1, with a breakpoint within 1p36.3. Subsequent FISH and array-based comparative genomic hybridization not only confirmed and partially characterized the deletion of chromosome 1p36.3, but also uncovered distal trisomy for 18q23. In this patient, the duplicated 18q23 is translocated onto the deleted 1p36.3 region, suggesting telomere capture. Molecular characterization of this novel der(1)t(1;18)(p36.3;q23), guided by our clinical array-comparative genomic hybridization, demonstrated a 3.2 Mb terminal deletion of chromosome 1p36.3 and a 200 kb duplication of 18q23 onto the deleted 1p36.3, presumably stabilizing the deleted chromosome 1. DNA sequence analysis around the breakpoints demonstrated no homology, and therefore this telomere capture of distal 18q is apparently the result of a non-homologous recombination. Partial trisomy for 18q23 has not been previously reported. The importance of mapping the breakpoints of all balanced and unbalanced translocations found in the clinical laboratory, when phenotypic abnormalities are found, is discussed.

  15. Sub-megabase resolution tiling (SMRT array-based comparative genomic hybridization profiling reveals novel gains and losses of chromosomal regions in Hodgkin Lymphoma and Anaplastic Large Cell Lymphoma cell lines

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    Lam Wan L

    2008-01-01

    Full Text Available Abstract Background Hodgkin lymphoma (HL and Anaplastic Large Cell Lymphoma (ALCL, are forms of malignant lymphoma defined by unique morphologic, immunophenotypic, genotypic, and clinical characteristics, but both overexpress CD30. We used sub-megabase resolution tiling (SMRT array-based comparative genomic hybridization to screen HL-derived cell lines (KMH2 and L428 and ALCL cell lines (DEL and SR-786 in order to identify disease-associated gene copy number gains and losses. Results Significant copy number gains and losses were observed on several chromosomes in all four cell lines. Assessment of copy number alterations with 26,819 DNA segments identified an average of 20 genetic alterations. Of the recurrent minimally altered regions identified, 11 (55% were within previously published regions of chromosomal alterations in HL and ALCL cell lines while 9 (45% were novel alterations not previously reported. HL cell lines L428 and KMH2 shared gains in chromosome cytobands 2q23.1-q24.2, 7q32.2-q36.3, 9p21.3-p13.3, 12q13.13-q14.1, and losses in 13q12.13-q12.3, and 18q21.32-q23. ALCL cell lines SR-786 and DEL, showed gains in cytobands 5p15.32-p14.3, 20p12.3-q13.11, and 20q13.2-q13.32. Both pairs of HL and ALCL cell lines showed losses in 18q21.32-18q23. Conclusion This study is considered to be the first one describing HL and ALCL cell line genomes at sub-megabase resolution. This high-resolution analysis allowed us to propose novel candidate target genes that could potentially contribute to the pathogenesis of HL and ALCL. FISH was used to confirm the amplification of all three isoforms of the trypsin gene (PRSS1/PRSS2/PRSS3 in KMH2 and L428 (HL and DEL (ALCL cell lines. These are novel findings that have not been previously reported in the lymphoma literature, and opens up an entirely new area of research that has not been previously associated with lymphoma biology. The findings raise interesting possibilities about the role of signaling

  16. Evolutionary insights from suffix array-based genome sequence analysis

    Indian Academy of Sciences (India)

    Anindya Poddar; Nagasuma Chandra; Madhavi Ganapathiraju; K Sekar; Judith Klein-Seetharaman; Raj Reddy; N Balakrishnan

    2007-08-01

    Gene and protein sequence analyses, central components of studies in modern biology are easily amenable to string matching and pattern recognition algorithms. The growing need of analysing whole genome sequences more efficiently and thoroughly, has led to the emergence of new computational methods. Suffix trees and suffix arrays are data structures, well known in many other areas and are highly suited for sequence analysis too. Here we report an improvement to the design of construction of suffix arrays. Enhancement in versatility and scalability, enabled by this approach, is demonstrated through the use of real-life examples. The scalability of the algorithm to whole genomes renders it suitable to address many biologically interesting problems. One example is the evolutionary insight gained by analysing unigrams, bi-grams and higher n-grams, indicating that the genetic code has a direct influence on the overall composition of the genome. Further, different proteomes have been analysed for the coverage of the possible peptide space, which indicate that as much as a quarter of the total space at the tetra-peptide level is left un-sampled in prokaryotic organisms, although almost all tri-peptides can be seen in one protein or another in a proteome. Besides, distinct patterns begin to emerge for the counts of particular tetra and higher peptides, indicative of a ‘meaning’ for tetra and higher n-grams. The toolkit has also been used to demonstrate the usefulness of identifying repeats in whole proteomes efficiently. As an example, 16 members of one COG, coded by the genome of Mycobacterium tuberculosis H37Rv have been found to contain a repeating sequence of 300 amino acids.

  17. High frequency of submicroscopic chromosomal imbalances in patients with syndromic craniosynostosis detected by a combined approach of microsatellite segregation analysis, multiplex ligation-dependent probe amplification and array-based comparative genome hybridisation.

    NARCIS (Netherlands)

    Jehee, F.S.; Krepischi-Santos, A.C.; Rocha, K.M.; Cavalcanti, D.P.; Kim, C.A.; Bertola, D.R.; Alonso, L.G.; D'Angelo, C.S.; Mazzeu, J.F.; Froyen, G.; Lugtenberg, D.; Vianna-Morgante, A.M.; Rosenberg, C.; Passos-Bueno, M.R.

    2008-01-01

    We present the first comprehensive study, to our knowledge, on genomic chromosomal analysis in syndromic craniosynostosis. In total, 45 patients with craniosynostotic disorders were screened with a variety of methods including conventional karyotype, microsatellite segregation analysis, subtelomeric

  18. 基于微阵列芯片的比较基因组杂交技术在临床实验室产前诊断中的应用%Prenatal diagnosis by array-based comparative genomic hybridization in the clinical laboratory setting

    Institute of Scientific and Technical Information of China (English)

    Amy M. BREMAN; 毕为民; 张秀慧

    2009-01-01

    Array-based comparative genomic hybridization (array CGH), a method used to detect gains or losses of genetic material, has recently been applied to prenatal diagnosis of genomic imbalance in the clinical laboratory setting. This new and exciting diagnostic tool represents a major technological step forward in cytogenetic testing and addresses many of the limitations of current cytogenetic methods.Conventional chromosome analysis, the current gold standard in prenatal diagnosis, focuses primarily on the detection of common aneuploidies and is limited by its capacity to detect only those copy number changes that are large enough to be microscopically visible (typically 5-6 Mb in size at the 500 band level). In contrast, array CGH analysis simultaneously evaluates regions across the entire genome and al-lows for detection of unbalanced structural and numerical chromosome abnormalities of less than one hun-dred kb. Array CGH analysis also overcomes some of the limitations of chromosome analysis, such as the requirement for cell culture and longer reporting time, by using direct uncultured fetal specimens. With many diagnostic laboratories now embracing this technology, the past year has seen tremendous growth in the use of array CGH analysis for prenatal diagnosis. This review aims to summarize array CGH methodology and its current applications in prenatal diagnosis.

  19. Comparison of buccal and blood-derived canine DNA, either native or whole genome amplified, for array-based genome-wide association studies

    Directory of Open Access Journals (Sweden)

    Lawley Cynthia

    2011-06-01

    Full Text Available Abstract Background The availability of array-based genotyping platforms for single nucleotide polymorphisms (SNPs for the canine genome has expanded the opportunities to undertake genome-wide association (GWA studies to identify the genetic basis for Mendelian and complex traits. Whole blood as the source of high quality DNA is undisputed but often proves impractical for collection of the large numbers of samples necessary to discover the loci underlying complex traits. Further, many countries prohibit the collection of blood from dogs unless medically necessary thereby restricting access to critical control samples from healthy dogs. Alternate sources of DNA, typically from buccal cytobrush extractions, while convenient, have been suggested to have low yield and perform poorly in GWA. Yet buccal cytobrushes provide a cost-effective means of collecting DNA, are readily accepted by dog owners, and represent a large resource base in many canine genetics laboratories. To increase the DNA quantities, whole genome amplification (WGA can be performed. Thus, the present study assessed the utility of buccal-derived DNA as well as whole genome amplification in comparison to blood samples for use on the most recent iteration of the canine HD SNP array (Illumina. Findings In both buccal and blood samples, whether whole genome amplified or not, 97% of the samples had SNP call rates in excess of 80% indicating that the vast majority of the SNPs would be suitable to perform association studies regardless of the DNA source. Similarly, there were no significant differences in marker intensity measurements between buccal and blood samples for copy number variations (CNV analysis. Conclusions All DNA samples assayed, buccal or blood, native or whole genome amplified, are appropriate for use in array-based genome-wide association studies. The concordance between subsets of dogs for which both buccal and blood samples, or those samples whole genome amplified, was

  20. Prenatal diagnosis of a fetus with partial trisomy 8p resulting from a balanced maternal translocation by array-based comparative genomic hybridization%微阵列比较基因组杂交技术产前诊断母源性8p部分三体胎儿一例

    Institute of Scientific and Technical Information of China (English)

    郭彩琴; 王峻峰; 赵丽; 刘俊; 王俊; 肖建平

    2015-01-01

    Objective To determine the karyotype of a fetus with transverse aortic arch hypoplasia,and to investigate the feasibility of array-based comparative genomic hybridization (array-CGH) for molecular genetic diagnosis.Methods G-banding was performed to analyze the karyotypes of the fetus and its parents,and array CGH was applied to identify the chromosomal abnormality of the fetus.Results G-banding analysis revealed that the pregnant woman has carried a balanced translocation 46,XX,t(8;16) (p21;q24),while the fetus has carried an unbalanced translocation 46,XX,der(16)t(8;16)(p21;q24)mat.Array-CGH analysis suggested that the derivative chromosomal fragment has originated from 8p with breakpoints in 8p23.3 p21.3.Conclusion Trisomy 8p23.3-p21.3 may have predisposed to transverse aortic arch hypoplasia in the fetus.Parental karyotype analysis could help to characterize the translocation and evaluate the recurrent risk.Compared with routine karyotype analysis,aCGH has a higher resolution and greater accuracy for mapping chromosomal aberrations.%目的 确定1例主动脉横弓发育不良胎儿的染色体核型,探讨微阵列比较基因组杂交(array based comparative genomic hybridization,array-CGH)技术在分子遗传学及产前诊断中的应用及优越性.方法 应用G显带分析胎儿及其父母的染色体核型,用array-CGH技术明确胎儿衍生染色体片段的来源和区域.结果 G显带染色体分析显示孕妇为46,XX,t(8;16)(p21;q24)平衡易位携带者,胎儿携带46,XX,der(16)t(8;16) (p21;q24)mat的非平衡易位.array-CGH检测证实胎儿衍生染色体片段源自8号染色体短臂,患儿为8p23.3 p21.3三体患儿.结论 胎儿的异常表型(主动脉横弓发育不良)与8p23.3p21.3三体密切相关,父母染色体分析可帮助明确易位性质及来源,从而有利于评估再发风险.array-CGH在染色体异常分析中具有更高的分辨率和准确性.

  1. From array-based hybridization of Helicobacter pylori isolates to the complete genome sequence of an isolate associated with MALT lymphoma

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    Mégraud Francis

    2010-06-01

    Full Text Available Abstract Background elicobacter pylori infection is associated with several gastro-duodenal inflammatory diseases of various levels of severity. To determine whether certain combinations of genetic markers can be used to predict the clinical source of the infection, we analyzed well documented and geographically homogenous clinical isolates using a comparative genomics approach. Results A set of 254 H. pylori genes was used to perform array-based comparative genomic hybridization among 120 French H. pylori strains associated with chronic gastritis (n = 33, duodenal ulcers (n = 27, intestinal metaplasia (n = 17 or gastric extra-nodal marginal zone B-cell MALT lymphoma (n = 43. Hierarchical cluster analyses of the DNA hybridization values allowed us to identify a homogeneous subpopulation of strains that clustered exclusively with cagPAI minus MALT lymphoma isolates. The genome sequence of B38, a representative of this MALT lymphoma strain-cluster, was completed, fully annotated, and compared with the six previously released H. pylori genomes (i.e. J99, 26695, HPAG1, P12, G27 and Shi470. B38 has the smallest H. pylori genome described thus far (1,576,758 base pairs containing 1,528 CDSs; it contains the vacAs2m2 allele and lacks the genes encoding the major virulence factors (absence of cagPAI, babB, babC, sabB, and homB. Comparative genomics led to the identification of very few sequences that are unique to the B38 strain (9 intact CDSs and 7 pseudogenes. Pair-wise genomic synteny comparisons between B38 and the 6 H. pylori sequenced genomes revealed an almost complete co-linearity, never seen before between the genomes of strain Shi470 (a Peruvian isolate and B38. Conclusion These isolates are deprived of the main H. pylori virulence factors characterized previously, but are nonetheless associated with gastric neoplasia.

  2. Supervised Lowess normalization of comparative genome hybridization data - application to lactococcal strain comparisons

    NARCIS (Netherlands)

    van Hijum, Sacha A. F. T.; Baerends, Richard J. S.; Zomer, Aldert L.; Karsens, Harma A.; Martin-Requena, Victoria; Trelles, Oswaldo; Kok, Jan; Kuipers, Oscar P.

    2008-01-01

    Background: Array-based comparative genome hybridization (aCGH) is commonly used to determine the genomic content of bacterial strains. Since prokaryotes in general have less conserved genome sequences than eukaryotes, sequence divergences between the genes in the genomes used for an aCGH experiment

  3. Prognostic impact of array-based genomic profiles in esophageal squamous cell cancer

    DEFF Research Database (Denmark)

    Carneiro, Ana; Isinger, Anna; Karlsson, Anna;

    2008-01-01

    interdependent alterations and deranged pathways were identified and copy number changes were correlated to stage, differentiation and survival. RESULTS: Copy number alterations affected median 19% of the genome and included recurrent gains of chromosome regions 5p, 7p, 7q, 8q, 10q, 11q, 12p, 14q, 16p, 17p, 19p...

  4. 微阵列比较基因组杂交技术在自然流产遗传学分析中的应用%Application of array-based comparative genomic hybridization technique in genetic analysis of ;patients with spontaneous abortion

    Institute of Scientific and Technical Information of China (English)

    楚艳; 吴东; 侯巧芳; 霍晓东; 高越; 王涛; 王红丹; 杨艳丽; 廖世秀

    2016-01-01

    目的:探讨微阵列比较基因组杂交(array-CGH)技术在自然流产组织染色体分析中的应用,为自然流产的遗传咨询和临床诊治提供指导。方法选取2013年11月至2016年1月在河南省人民医院就诊的自然流产患者382例,收集流产绒毛或胎儿组织,采用array-CGH技术对流产绒毛或胎儿组织的全基因组拷贝数进行检测,并同时行细胞培养和传统G显带染色体核型分析,比较G显带染色体核型分析及array-CGH的结果。结果 array-CGH技术成功获得结果382例,检测成功率为100.0%(382/382),染色体异常检出率为46.6%(178/382);染色体核型分析技术成功获得结果281例,检测成功率为73.6%(281/382),染色体异常检出率为40.2%(113/281);array-CGH均高于染色体核型分析技术。array-CGH检测出的178例染色体异常中,染色体数目异常163例(91.6%,163/178);染色体结构异常15例(8.4%,15/178),其中10例同时出现了染色体微重复和微缺失的流产胚胎中有4例被证实父母一方为染色体平衡易位携带者。染色体核型分析检出的113例染色体异常中,染色体数目异常108例(95.6%,108/113),染色体结构异常5例(4.4%,5/113)。两种方法的结果不一致有3例,其中2例为三倍体、1例为性染色体低比例嵌合,array-CGH均漏检为正常。结论 array-CGH技术用于自然流产胚胎组织的染色体分析成功率高,对标本的取材要求远低于传统染色体核型分析技术,且分辨率高、准确快速,可以作为流产组织遗传学诊断的一线技术。%Objective To investigate the value of array-based comparative genomic hybridization (array-CGH) technique for the detection of chromosomal analysis of miscarried embryo, and to provide genetic counseling for couples with spontaneous abortion. Methods Totally 382 patients who underwent miscarriage were enrolled in this study. All

  5. Diagnostic value of array-based single nucleotide polymorphisms comparative genomic hybridization in An-gelman syndrome%单核苷酸多态性比较基因组杂交技术对Angelman综合征的诊断价值

    Institute of Scientific and Technical Information of China (English)

    高晶; 何玺玉; 杨尧; 吴虹林

    2015-01-01

    Objective To analyze the genotype-phenotype correlations of Angelman syndrome ( AS ) , and to discuss the advantage of applying array-based single nucleotide polymorphisms comparative genomic hybridization ( SNP aCGH) in diagnosis of AS. Methods Examination of electroencephalogram( EEG) and intelligence quotient( IQ) evaluation were done for 11 cases diagnosed as AS clinically. Gesell scares were chosen as the evaluation criterion of IQ. The screening techniques was methylation polymerase chain reaction( MS-PCR) ,then SNP aCGH was used to make genetic diagnosis. Results (1)Eleven cases of AS were confirmed:1 case had UPD(uniparental disomy),10 cases were type of deletion, from which 6 cases were deletion (Ⅱ) , 4 cases were deletion (Ⅰ) . ( 2 ) The copy number variations were detected in the region of 15q11-q13,which contained genes like MKRN3,MAGEL2,NDN,SNRPN, SNURF,GABRB3,GABRA5,GABRG3,UBE3A,OCA2,ATP10A. To search online Mendelian inheritance in man,genes above were correlated with AS manifestation. (3)All cases of deletion were 3-5 standard deviation(SD) in weight and height to normal children at the same age and with the same sex,while UPD was below 1. 5 SD. Gesell scares showed that the deletion(Ⅰ) was the most serious in mental retardation,deletion(Ⅱ) was moderate,and the UPD was mild. Eight cases were hypopigmentation,and one was the UPD. EEG revealed that 1 case of deletion(Ⅰ) and the UPD were spike occasionally,another one deletion(Ⅰ) was limit EEG. The rest cases displayed slow and spike waves paroxysmal-ly,with amplitude of medium or high,2. 5-3. 0 Hz. Conclusions Not only can SNP aCGH make a diagnosis of AS but discriminate the types of genetic pathology. Since different type contributes to a diverse of clinical features and the rate of recurrence is also different,it is significant for family genetic consultation. Moreover,the technology is advantageous for the study on the pathogenesis and gene function.%目的:分析Angelman

  6. Rodent malaria parasites : genome organization & comparative genomics

    NARCIS (Netherlands)

    Kooij, Taco W.A.

    2006-01-01

    The aim of the studies described in this thesis was to investigate the genome organization of rodent malaria parasites (RMPs) and compare the organization and gene content of the genomes of RMPs and the human malaria parasite P. falciparum. The release of the complete genome sequence of P. falciparu

  7. Phytozome Comparative Plant Genomics Portal

    Energy Technology Data Exchange (ETDEWEB)

    Goodstein, David; Batra, Sajeev; Carlson, Joseph; Hayes, Richard; Phillips, Jeremy; Shu, Shengqiang; Schmutz, Jeremy; Rokhsar, Daniel

    2014-09-09

    The Dept. of Energy Joint Genome Institute is a genomics user facility supporting DOE mission science in the areas of Bioenergy, Carbon Cycling, and Biogeochemistry. The Plant Program at the JGI applies genomic, analytical, computational and informatics platforms and methods to: 1. Understand and accelerate the improvement (domestication) of bioenergy crops 2. Characterize and moderate plant response to climate change 3. Use comparative genomics to identify constrained elements and infer gene function 4. Build high quality genomic resource platforms of JGI Plant Flagship genomes for functional and experimental work 5. Expand functional genomic resources for Plant Flagship genomes

  8. Genome Mapping in Plant Comparative Genomics.

    Science.gov (United States)

    Chaney, Lindsay; Sharp, Aaron R; Evans, Carrie R; Udall, Joshua A

    2016-09-01

    Genome mapping produces fingerprints of DNA sequences to construct a physical map of the whole genome. It provides contiguous, long-range information that complements and, in some cases, replaces sequencing data. Recent advances in genome-mapping technology will better allow researchers to detect large (>1kbp) structural variations between plant genomes. Some molecular and informatics complications need to be overcome for this novel technology to achieve its full utility. This technology will be useful for understanding phenotype responses due to DNA rearrangements and will yield insights into genome evolution, particularly in polyploids. In this review, we outline recent advances in genome-mapping technology, including the processes required for data collection and analysis, and applications in plant comparative genomics.

  9. Comparative genomic hybridization: practical guidelines.

    NARCIS (Netherlands)

    Jeuken, J.W.M.; Sprenger, S.H.; Wesseling, P.

    2002-01-01

    Comparative genomic hybridization (CGH) is a technique used to identify copy number changes throughout a genome. Until now, hundreds of CGH studies have been published reporting chromosomal imbalances in a large variety of human neoplasms. Additionally, technical improvements of specific steps in a

  10. Exclusion of APC and VHL gene deletions by array-based comparative hybridization in two patients with microscopically visible chromosomal aberrations.

    Science.gov (United States)

    Wallerstein, Robert J; Brooks, Susan Sklower; Streck, Deanna L; Kurvathi, Rohini; Toruner, Gokce A

    2007-10-15

    Karyotyping is a major component of the genetic work-up of patients with dysmorphism. Cytogenetic aberrations close to a known tumor suppressor gene raise important clinical issues because deletion of that tumor suppressor gene can cause genetic predisposition to cancer. We present two cancer-free dysmorphic patients with karyotypes of 46,XX,del(5)(q15q22.3) and 46,XX,del(3)(p25.2~pter). These deletions are close to the APC and VHL genes that confer susceptibility to familial Adenomatous polyposis (OMIM #17510) and von-Hippel-Lindau syndrome (OMIM #193300), respectively. The array-based comparative genomic hybridization (array-CGH) analysis using a custom Agilent 44K oligonucleotide array demonstrated an interstitial 20.7-megabase (Mb) deletion on 5q (chr5: 89,725,638-110,491,345) and a terminal 9.45-Mb deletion on 3p (chr3:pter-9,450,984). According to the March 2006 human reference sequence, the APC gene is located at chr5: 112,101,483-112,209,835 and the VHL gene is located at chr3: 10,158,319-10,168,746. These results indicate that the APC gene is 2,300 kilobases (kb) and the VHL gene is 700 kb away from deleted regions. Southern blot analysis for APC and VHL genes were negative, consistent with array-CGH findings. These results demonstrate the power of array-CCH to assess potential tumor suppressor gene involvement and cancer risk in patients with microscopically visible deletions in areas near tumor suppressors.

  11. Comparative genomics of Helicobacter pylori

    Institute of Scientific and Technical Information of China (English)

    Quan-Jiang Dong; Qing Wang; Ying-Nin Xin; Ni Li; Shi-Ying Xuan

    2009-01-01

    Genomic sequences have been determined for a number of strains of Helicobacter pylori (H pylori) and related bacteria.With the development of microarray analysis and the wide use of subtractive hybridization techniques,comparative studies have been carried out with respect to the interstrain differences between H pylori and inter-species differences in the genome of related bacteria.It was found that the core genome of H pylori constitutes 1111 genes that are determinants of the species properties.A great pool of auxillary genes are mainly from the categories of cag pathogenicity islands,outer membrane proteins,restriction-modification system and hypothetical proteins of unknown function.Persistence of H pylori in the human stomach leads to the diversification of the genome.Comparative genomics suggest that a host jump has occurs from humans to felines.Candidate genes specific for the development of the gastric diseases were identified.With the aid of proteomics,population genetics and other molecular methods,future comparative genomic studies would dramatically promote our understanding of the evolution,pathogenesis and microbiology of H pylori.

  12. Array-based techniques for fingerprinting medicinal herbs

    Directory of Open Access Journals (Sweden)

    Xue Charlie

    2011-05-01

    Full Text Available Abstract Poor quality control of medicinal herbs has led to instances of toxicity, poisoning and even deaths. The fundamental step in quality control of herbal medicine is accurate identification of herbs. Array-based techniques have recently been adapted to authenticate or identify herbal plants. This article reviews the current array-based techniques, eg oligonucleotides microarrays, gene-based probe microarrays, Suppression Subtractive Hybridization (SSH-based arrays, Diversity Array Technology (DArT and Subtracted Diversity Array (SDA. We further compare these techniques according to important parameters such as markers, polymorphism rates, restriction enzymes and sample type. The applicability of the array-based methods for fingerprinting depends on the availability of genomics and genetics of the species to be fingerprinted. For the species with few genome sequence information but high polymorphism rates, SDA techniques are particularly recommended because they require less labour and lower material cost.

  13. Enhancer Identification through Comparative Genomics

    Energy Technology Data Exchange (ETDEWEB)

    Visel, Axel; Bristow, James; Pennacchio, Len A.

    2006-10-01

    With the availability of genomic sequence from numerousvertebrates, a paradigm shift has occurred in the identification ofdistant-acting gene regulatory elements. In contrast to traditionalgene-centric studies in which investigators randomly scanned genomicfragments that flank genes of interest in functional assays, the modernapproach begins electronically with publicly available comparativesequence datasets that provide investigators with prioritized lists ofputative functional sequences based on their evolutionary conservation.However, although a large number of tools and resources are nowavailable, application of comparative genomic approaches remains far fromtrivial. In particular, it requires users to dynamically consider thespecies and methods for comparison depending on the specific biologicalquestion under investigation. While there is currently no single generalrule to this end, it is clear that when applied appropriately,comparative genomic approaches exponentially increase our power ingenerating biological hypotheses for subsequent experimentaltesting.

  14. Comparative genomics of Dothideomycete fungi

    NARCIS (Netherlands)

    Burgt, van der A.

    2014-01-01

    Fungi are a diverse group of eukaryotic micro-organisms particularly suited for comparative genomics analyses. Fungi are important to industry, fundamental science and many of them are notorious pathogens of crops, thereby endangering global food supply. Dozens of fungi have been sequenced in the la

  15. Comparative Genome Analysis and Genome Evolution

    NARCIS (Netherlands)

    Snel, Berend

    2003-01-01

    This thesis described a collection of bioinformatic analyses on complete genome sequence data. We have studied the evolution of gene content and find that vertical inheritance dominates over horizontal gene trasnfer, even to the extent that we can use the gene content to make genome phylogenies. Usi

  16. A reusable laser wrapped graphene-Ag array based SERS sensor for trace detection of genomic DNA methylation.

    Science.gov (United States)

    Ouyang, Lei; Hu, Yaowu; Zhu, Lihua; Cheng, Gary J; Irudayaraj, Joseph

    2017-06-15

    Methylation is an important epigenetic DNA modification that governs gene expression. The genomic level of methylated DNA and its derivatives may serve as important indicators for the initiation and progression of cancers among other diseases. In this effort we propose a new laser wrapped graphene-Ag array as a highly sensitive Surface-enhanced Raman spectroscopy (SERS) sensor for the detection of methylated DNA (5-methylcytosine, 5mC) and its oxidation derivatives namely 5-hydroxymethylcytosine (5-hmC) and 5-carboxylcytosine (5-caC). Excellent sensitivity and reproducibility were achieved with the laser wrapped graphene-Ag array as a substrate, with the graphene layer acting as an enhancer of the SERS signal due to the effective coupling of the electromagnetic field. In summary, fast (less than 60min) and sensitive (at a limit of detection 0.2pgμL(-1), ie. 1.8pmolL(-1)) detection of methylated DNA and its derivatives was realized with the ability to distinguish methylation levels from a mixture at 0.1%. The sensitive and accurate detection in DNA extracted from cells was also accomplished. Furthermore our graphene wrapped approach circumvents the direct interaction between Ag array and the analytes, thus improving the reusability of the SERS substrate even after five cycles of use.

  17. Comparative genomics of Lactobacillus and other LAB

    DEFF Research Database (Denmark)

    Wassenaar, Trudy M.; Lukjancenko, Oksana

    2014-01-01

    The genomes of 66 LABs, belonging to five different genera, were compared for genome size and gene content. The analyzed genomes included 37 Lactobacillus genomes of 17 species, six Lactococcus lactis genomes, four Leuconostoc genomes of three species, six Streptococcus genomes of two species...... that of the others, with the two Streptococcus species having the shortest genomes. The widest distribution in genome content was observed for Lactobacillus. The number of tRNA and rRNA gene copies varied considerably, with exceptional high numbers observed for Lb. delbrueckii, while these numbers were relatively...

  18. Comparative genomics of Listeria species.

    Science.gov (United States)

    Glaser, P; Frangeul, L; Buchrieser, C; Rusniok, C; Amend, A; Baquero, F; Berche, P; Bloecker, H; Brandt, P; Chakraborty, T; Charbit, A; Chetouani, F; Couvé, E; de Daruvar, A; Dehoux, P; Domann, E; Domínguez-Bernal, G; Duchaud, E; Durant, L; Dussurget, O; Entian, K D; Fsihi, H; García-del Portillo, F; Garrido, P; Gautier, L; Goebel, W; Gómez-López, N; Hain, T; Hauf, J; Jackson, D; Jones, L M; Kaerst, U; Kreft, J; Kuhn, M; Kunst, F; Kurapkat, G; Madueno, E; Maitournam, A; Vicente, J M; Ng, E; Nedjari, H; Nordsiek, G; Novella, S; de Pablos, B; Pérez-Diaz, J C; Purcell, R; Remmel, B; Rose, M; Schlueter, T; Simoes, N; Tierrez, A; Vázquez-Boland, J A; Voss, H; Wehland, J; Cossart, P

    2001-10-26

    Listeria monocytogenes is a food-borne pathogen with a high mortality rate that has also emerged as a paradigm for intracellular parasitism. We present and compare the genome sequences of L. monocytogenes (2,944,528 base pairs) and a nonpathogenic species, L. innocua (3,011,209 base pairs). We found a large number of predicted genes encoding surface and secreted proteins, transporters, and transcriptional regulators, consistent with the ability of both species to adapt to diverse environments. The presence of 270 L. monocytogenes and 149 L. innocua strain-specific genes (clustered in 100 and 63 islets, respectively) suggests that virulence in Listeria results from multiple gene acquisition and deletion events.

  19. Gramene database: navigating plant comparative genomics resources

    Science.gov (United States)

    Gramene (http://www.gramene.org) is an online, open source, curated resource for plant comparative genomics and pathway analysis designed to support researchers working in plant genomics, breeding, evolutionary biology, system biology, and metabolic engineering. It exploits phylogenetic relationship...

  20. Cocoa/Cotton Comparative Genomics

    Science.gov (United States)

    With genome sequence from two members of the Malvaceae family recently made available, we are exploring syntenic relationships, gene content, and evolutionary trajectories between the cacao and cotton genomes. An assembly of cacao (Theobroma cacao) using Illumina and 454 sequence technology yielded ...

  1. A High-Resolution SNP Array-Based Linkage Map Anchors a New Domestic Cat Draft Genome Assembly and Provides Detailed Patterns of Recombination.

    Science.gov (United States)

    Li, Gang; Hillier, LaDeana W; Grahn, Robert A; Zimin, Aleksey V; David, Victor A; Menotti-Raymond, Marilyn; Middleton, Rondo; Hannah, Steven; Hendrickson, Sher; Makunin, Alex; O'Brien, Stephen J; Minx, Pat; Wilson, Richard K; Lyons, Leslie A; Warren, Wesley C; Murphy, William J

    2016-06-01

    High-resolution genetic and physical maps are invaluable tools for building accurate genome assemblies, and interpreting results of genome-wide association studies (GWAS). Previous genetic and physical maps anchored good quality draft assemblies of the domestic cat genome, enabling the discovery of numerous genes underlying hereditary disease and phenotypes of interest to the biomedical science and breeding communities. However, these maps lacked sufficient marker density to order thousands of shorter scaffolds in earlier assemblies, which instead relied heavily on comparative mapping with related species. A high-resolution map would aid in validating and ordering chromosome scaffolds from existing and new genome assemblies. Here, we describe a high-resolution genetic linkage map of the domestic cat genome based on genotyping 453 domestic cats from several multi-generational pedigrees on the Illumina 63K SNP array. The final maps include 58,055 SNP markers placed relative to 6637 markers with unique positions, distributed across all autosomes and the X chromosome. Our final sex-averaged maps span a total autosomal length of 4464 cM, the longest described linkage map for any mammal, confirming length estimates from a previous microsatellite-based map. The linkage map was used to order and orient the scaffolds from a substantially more contiguous domestic cat genome assembly (Felis catus v8.0), which incorporated ∼20 × coverage of Illumina fragment reads. The new genome assembly shows substantial improvements in contiguity, with a nearly fourfold increase in N50 scaffold size to 18 Mb. We use this map to report probable structural errors in previous maps and assemblies, and to describe features of the recombination landscape, including a massive (∼50 Mb) recombination desert (of virtually zero recombination) on the X chromosome that parallels a similar desert on the porcine X chromosome in both size and physical location.

  2. Comparative Reannotation of 21 Aspergillus Genomes

    Energy Technology Data Exchange (ETDEWEB)

    Salamov, Asaf; Riley, Robert; Kuo, Alan; Grigoriev, Igor

    2013-03-08

    We used comparative gene modeling to reannotate 21 Aspergillus genomes. Initial automatic annotation of individual genomes may contain some errors of different nature, e.g. missing genes, incorrect exon-intron structures, 'chimeras', which fuse 2 or more real genes or alternatively splitting some real genes into 2 or more models. The main premise behind the comparative modeling approach is that for closely related genomes most orthologous families have the same conserved gene structure. The algorithm maps all gene models predicted in each individual Aspergillus genome to the other genomes and, for each locus, selects from potentially many competing models, the one which most closely resembles the orthologous genes from other genomes. This procedure is iterated until no further change in gene models is observed. For Aspergillus genomes we predicted in total 4503 new gene models ( ~;;2percent per genome), supported by comparative analysis, additionally correcting ~;;18percent of old gene models. This resulted in a total of 4065 more genes with annotated PFAM domains (~;;3percent increase per genome). Analysis of a few genomes with EST/transcriptomics data shows that the new annotation sets also have a higher number of EST-supported splice sites at exon-intron boundaries.

  3. Comparative Genomics of Green Sulfur Bacteria

    DEFF Research Database (Denmark)

    Ussery, David; Davenport, C; Tümmler, B

    2010-01-01

    Eleven completely sequenced Chlorobi genomes were compared in oligonucleotide usage, gene contents, and synteny. The green sulfur bacteria (GSB) are equipped with a core genome that sustains their anoxygenic phototrophic lifestyle by photosynthesis, sulfur oxidation, and CO(2) fixation. Whole...... weight of 10(6), and are probably instrumental for the bacteria to generate their own intimate (micro)environment....

  4. Comparative genomic analysis of esophageal cancers.

    Science.gov (United States)

    Caygill, Christine P J; Gatenby, Piers A C; Herceg, Zdenko; Lima, Sheila C S; Pinto, Luis F R; Watson, Anthony; Wu, Ming-Shiang

    2014-09-01

    The following, from the 12th OESO World Conference: Cancers of the Esophagus, includes commentaries on comparative genomic analysis of esophageal cancers: genomic polymorphisms, the genetic and epigenetic drivers in esophageal cancers, and the collection of data in the UK Barrett's Oesophagus Registry.

  5. Gramene database: Navigating plant comparative genomics resources

    Directory of Open Access Journals (Sweden)

    Parul Gupta

    2016-11-01

    Full Text Available Gramene (http://www.gramene.org is an online, open source, curated resource for plant comparative genomics and pathway analysis designed to support researchers working in plant genomics, breeding, evolutionary biology, system biology, and metabolic engineering. It exploits phylogenetic relationships to enrich the annotation of genomic data and provides tools to perform powerful comparative analyses across a wide spectrum of plant species. It consists of an integrated portal for querying, visualizing and analyzing data for 44 plant reference genomes, genetic variation data sets for 12 species, expression data for 16 species, curated rice pathways and orthology-based pathway projections for 66 plant species including various crops. Here we briefly describe the functions and uses of the Gramene database.

  6. The CGView Server: a comparative genomics tool for circular genomes.

    Science.gov (United States)

    Grant, Jason R; Stothard, Paul

    2008-07-01

    The CGView Server generates graphical maps of circular genomes that show sequence features, base composition plots, analysis results and sequence similarity plots. Sequences can be supplied in raw, FASTA, GenBank or EMBL format. Additional feature or analysis information can be submitted in the form of GFF (General Feature Format) files. The server uses BLAST to compare the primary sequence to up to three comparison genomes or sequence sets. The BLAST results and feature information are converted to a graphical map showing the entire sequence, or an expanded and more detailed view of a region of interest. Several options are included to control which types of features are displayed and how the features are drawn. The CGView Server can be used to visualize features associated with any bacterial, plasmid, chloroplast or mitochondrial genome, and can aid in the identification of conserved genome segments, instances of horizontal gene transfer, and differences in gene copy number. Because a collection of sequences can be used in place of a comparison genome, maps can also be used to visualize regions of a known genome covered by newly obtained sequence reads. The CGView Server can be accessed at http://stothard.afns.ualberta.ca/cgview_server/

  7. Sequencing and comparing whole mitochondrial genomes ofanimals

    Energy Technology Data Exchange (ETDEWEB)

    Boore, Jeffrey L.; Macey, J. Robert; Medina, Monica

    2005-04-22

    Comparing complete animal mitochondrial genome sequences is becoming increasingly common for phylogenetic reconstruction and as a model for genome evolution. Not only are they much more informative than shorter sequences of individual genes for inferring evolutionary relatedness, but these data also provide sets of genome-level characters, such as the relative arrangements of genes, that can be especially powerful. We describe here the protocols commonly used for physically isolating mtDNA, for amplifying these by PCR or RCA, for cloning,sequencing, assembly, validation, and gene annotation, and for comparing both sequences and gene arrangements. On several topics, we offer general observations based on our experiences to date with determining and comparing complete mtDNA sequences.

  8. VISTA - computational tools for comparative genomics

    Energy Technology Data Exchange (ETDEWEB)

    Frazer, Kelly A.; Pachter, Lior; Poliakov, Alexander; Rubin,Edward M.; Dubchak, Inna

    2004-01-01

    Comparison of DNA sequences from different species is a fundamental method for identifying functional elements in genomes. Here we describe the VISTA family of tools created to assist biologists in carrying out this task. Our first VISTA server at http://www-gsd.lbl.gov/VISTA/ was launched in the summer of 2000 and was designed to align long genomic sequences and visualize these alignments with associated functional annotations. Currently the VISTA site includes multiple comparative genomics tools and provides users with rich capabilities to browse pre-computed whole-genome alignments of large vertebrate genomes and other groups of organisms with VISTA Browser, submit their own sequences of interest to several VISTA servers for various types of comparative analysis, and obtain detailed comparative analysis results for a set of cardiovascular genes. We illustrate capabilities of the VISTA site by the analysis of a 180 kilobase (kb) interval on human chromosome 5 that encodes for the kinesin family member3A (KIF3A) protein.

  9. Array-based genome-wide RNAi screening to identify shRNAs that enhance p53-related apoptosis in human cancer cells.

    Science.gov (United States)

    Idogawa, Masashi; Ohashi, Tomoko; Sugisaka, Jun; Sasaki, Yasushi; Suzuki, Hiromu; Tokino, Takashi

    2014-09-15

    p53 transduction is a potentially effective cancer therapy but does not result in a good therapeutic response in all human cancers due to resistance to apoptosis. To discover factors that overcome resistance to p53-induced apoptosis, we attempted to identify RNAi sequences that enhance p53-induced apoptosis. We screened a genome-wide lentiviral shRNA library in liver cancer Huh-7 and pancreatic cancer Panc-1 cells, both of which resist p53-induced apoptosis. After the infection of adenovirus expressing p53 or LacZ as a control, shRNA-treated populations were analyzed by microarray. We identified shRNAs that were significantly decreased in p53-infected cells compared with control cells. Among these shRNAs, shRNA-58335 was markedly decreased in both cancer cell lines tested. shRNA-58335 enhanced p53-related apoptosis in vitro and augmented the inhibitory effect of adenoviral p53 transduction on tumor growth in vivo. Furthermore, the enhanced apoptotic response by shRNA-58335 was also confirmed by treatment with PRIMA-1, which reactivates mutant p53, instead of adenoviral p53 transduction. We found that shRNA-58335 evokes the apoptotic response following p53 transduction or functional restoration of p53 with a small molecule drug in cancer cells resistant to p53-induced apoptosis. The combination of p53 restoration and RNAi-based drugs is expected to be a promising novel cancer therapy.

  10. Comparative genomics of Shiga toxin encoding bacteriophages

    Directory of Open Access Journals (Sweden)

    Smith Darren L

    2012-07-01

    Full Text Available Abstract Background Stx bacteriophages are responsible for driving the dissemination of Stx toxin genes (stx across their bacterial host range. Lysogens carrying Stx phages can cause severe, life-threatening disease and Stx toxin is an integral virulence factor. The Stx-bacteriophage vB_EcoP-24B, commonly referred to as Ф24B, is capable of multiply infecting a single bacterial host cell at a high frequency, with secondary infection increasing the rate at which subsequent bacteriophage infections can occur. This is biologically unusual, therefore determining the genomic content and context of Ф24B compared to other lambdoid Stx phages is important to understanding the factors controlling this phenomenon and determining whether they occur in other Stx phages. Results The genome of the Stx2 encoding phage, Ф24B was sequenced and annotated. The genomic organisation and general features are similar to other sequenced Stx bacteriophages induced from Enterohaemorrhagic Escherichia coli (EHEC, however Ф24B possesses significant regions of heterogeneity, with implications for phage biology and behaviour. The Ф24B genome was compared to other sequenced Stx phages and the archetypal lambdoid phage, lambda, using the Circos genome comparison tool and a PCR-based multi-loci comparison system. Conclusions The data support the hypothesis that Stx phages are mosaic, and recombination events between the host, phages and their remnants within the same infected bacterial cell will continue to drive the evolution of Stx phage variants and the subsequent dissemination of shigatoxigenic potential.

  11. DNAVis: interactive visualization of comparative genome annotations

    NARCIS (Netherlands)

    Fiers, M.W.E.J.; Wetering, van de H.; Peeters, T.H.J.M.; Wijk, van J.J.; Nap, J.P.H.

    2006-01-01

    The software package DNAVis offers a fast, interactive and real-time visualization of DNA sequences and their comparative genome annotations. DNAVis implements advanced methods of information visualization such as linked views, perspective walls and semantic zooming, in addition to the display of he

  12. Diagnosis and Prognostication of Ductal Adenocarcinomas of the Pancreas Based on Genome-Wide DNA Methylation Profiling by Bacterial Artificial Chromosome Array-Based Methylated CpG Island Amplification

    Directory of Open Access Journals (Sweden)

    Masahiro Gotoh

    2011-01-01

    Full Text Available To establish diagnostic criteria for ductal adenocarcinomas of the pancreas (PCs, bacterial artificial chromosome (BAC array-based methylated CpG island amplification was performed using 139 tissue samples. Twelve BAC clones, for which DNA methylation status was able to discriminate cancerous tissue (T from noncancerous pancreatic tissue in the learning cohort with a specificity of 100%, were identified. Using criteria that combined the 12 BAC clones, T-samples were diagnosed as cancers with 100% sensitivity and specificity in both the learning and validation cohorts. DNA methylation status on 11 of the BAC clones, which was able to discriminate patients showing early relapse from those with no relapse in the learning cohort with 100% specificity, was correlated with the recurrence-free and overall survival rates in the validation cohort and was an independent prognostic factor by multivariate analysis. Genome-wide DNA methylation profiling may provide optimal diagnostic markers and prognostic indicators for patients with PCs.

  13. Whole-genome sequencing for comparative genomics and de novo genome assembly.

    Science.gov (United States)

    Benjak, Andrej; Sala, Claudia; Hartkoorn, Ruben C

    2015-01-01

    Next-generation sequencing technologies for whole-genome sequencing of mycobacteria are rapidly becoming an attractive alternative to more traditional sequencing methods. In particular this technology is proving useful for genome-wide identification of mutations in mycobacteria (comparative genomics) as well as for de novo assembly of whole genomes. Next-generation sequencing however generates a vast quantity of data that can only be transformed into a usable and comprehensible form using bioinformatics. Here we describe the methodology one would use to prepare libraries for whole-genome sequencing, and the basic bioinformatics to identify mutations in a genome following Illumina HiSeq or MiSeq sequencing, as well as de novo genome assembly following sequencing using Pacific Biosciences (PacBio).

  14. Comparative genomics of brain size evolution

    OpenAIRE

    2014-01-01

    Which genetic changes took place during mammalian, primate and human evolution to build a larger brain? To answer this question, one has to correlate genetic changes with brain size changes across a phylogeny. Such a comparative genomics approach provides unique information to better understand brain evolution and brain development. However, its statistical power is limited for example due to the limited number of species, the presumably complex genetics of brain size evolution and the large ...

  15. Comparative genomics of biotechnologically important yeasts.

    Science.gov (United States)

    Riley, Robert; Haridas, Sajeet; Wolfe, Kenneth H; Lopes, Mariana R; Hittinger, Chris Todd; Göker, Markus; Salamov, Asaf A; Wisecaver, Jennifer H; Long, Tanya M; Calvey, Christopher H; Aerts, Andrea L; Barry, Kerrie W; Choi, Cindy; Clum, Alicia; Coughlan, Aisling Y; Deshpande, Shweta; Douglass, Alexander P; Hanson, Sara J; Klenk, Hans-Peter; LaButti, Kurt M; Lapidus, Alla; Lindquist, Erika A; Lipzen, Anna M; Meier-Kolthoff, Jan P; Ohm, Robin A; Otillar, Robert P; Pangilinan, Jasmyn L; Peng, Yi; Rokas, Antonis; Rosa, Carlos A; Scheuner, Carmen; Sibirny, Andriy A; Slot, Jason C; Stielow, J Benjamin; Sun, Hui; Kurtzman, Cletus P; Blackwell, Meredith; Grigoriev, Igor V; Jeffries, Thomas W

    2016-08-30

    Ascomycete yeasts are metabolically diverse, with great potential for biotechnology. Here, we report the comparative genome analysis of 29 taxonomically and biotechnologically important yeasts, including 16 newly sequenced. We identify a genetic code change, CUG-Ala, in Pachysolen tannophilus in the clade sister to the known CUG-Ser clade. Our well-resolved yeast phylogeny shows that some traits, such as methylotrophy, are restricted to single clades, whereas others, such as l-rhamnose utilization, have patchy phylogenetic distributions. Gene clusters, with variable organization and distribution, encode many pathways of interest. Genomics can predict some biochemical traits precisely, but the genomic basis of others, such as xylose utilization, remains unresolved. Our data also provide insight into early evolution of ascomycetes. We document the loss of H3K9me2/3 heterochromatin, the origin of ascomycete mating-type switching, and panascomycete synteny at the MAT locus. These data and analyses will facilitate the engineering of efficient biosynthetic and degradative pathways and gateways for genomic manipulation.

  16. Comparative genome analysis of Basidiomycete fungi

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Robert; Salamov, Asaf; Henrissat, Bernard; Nagy, Laszlo; Brown, Daren; Held, Benjamin; Baker, Scott; Blanchette, Robert; Boussau, Bastien; Doty, Sharon L.; Fagnan, Kirsten; Floudas, Dimitris; Levasseur, Anthony; Manning, Gerard; Martin, Francis; Morin, Emmanuelle; Otillar, Robert; Pisabarro, Antonio; Walton, Jonathan; Wolfe, Ken; Hibbett, David; Grigoriev, Igor

    2013-08-07

    Fungi of the phylum Basidiomycota (basidiomycetes), make up some 37percent of the described fungi, and are important in forestry, agriculture, medicine, and bioenergy. This diverse phylum includes symbionts, pathogens, and saprotrophs including the majority of wood decaying and ectomycorrhizal species. To better understand the genetic diversity of this phylum we compared the genomes of 35 basidiomycetes including 6 newly sequenced genomes. These genomes span extremes of genome size, gene number, and repeat content. Analysis of core genes reveals that some 48percent of basidiomycete proteins are unique to the phylum with nearly half of those (22percent) found in only one organism. Correlations between lifestyle and certain gene families are evident. Phylogenetic patterns of plant biomass-degrading genes in Agaricomycotina suggest a continuum rather than a dichotomy between the white rot and brown rot modes of wood decay. Based on phylogenetically-informed PCA analysis of wood decay genes, we predict that that Botryobasidium botryosum and Jaapia argillacea have properties similar to white rot species, although neither has typical ligninolytic class II fungal peroxidases (PODs). This prediction is supported by growth assays in which both fungi exhibit wood decay with white rot-like characteristics. Based on this, we suggest that the white/brown rot dichotomy may be inadequate to describe the full range of wood decaying fungi. Analysis of the rate of discovery of proteins with no or few homologs suggests the value of continued sequencing of basidiomycete fungi.

  17. Genomic alterations detected by comparative genomic hybridization in ovarian endometriomas

    Directory of Open Access Journals (Sweden)

    L.C. Veiga-Castelli

    2010-08-01

    Full Text Available Endometriosis is a complex and multifactorial disease. Chromosomal imbalance screening in endometriotic tissue can be used to detect hot-spot regions in the search for a possible genetic marker for endometriosis. The objective of the present study was to detect chromosomal imbalances by comparative genomic hybridization (CGH in ectopic tissue samples from ovarian endometriomas and eutopic tissue from the same patients. We evaluated 10 ovarian endometriotic tissues and 10 eutopic endometrial tissues by metaphase CGH. CGH was prepared with normal and test DNA enzymatically digested, ligated to adaptors and amplified by PCR. A second PCR was performed for DNA labeling. Equal amounts of both normal and test-labeled DNA were hybridized in human normal metaphases. The Isis FISH Imaging System V 5.0 software was used for chromosome analysis. In both eutopic and ectopic groups, 4/10 samples presented chromosomal alterations, mainly chromosomal gains. CGH identified 11q12.3-q13.1, 17p11.1-p12, 17q25.3-qter, and 19p as critical regions. Genomic imbalances in 11q, 17p, 17q, and 19p were detected in normal eutopic and/or ectopic endometrium from women with ovarian endometriosis. These regions contain genes such as POLR2G, MXRA7 and UBA52 involved in biological processes that may lead to the establishment and maintenance of endometriotic implants. This genomic imbalance may affect genes in which dysregulation impacts both eutopic and ectopic endometrium.

  18. Comparative genomics of bifidobacterium, lactobacillus and related probiotic genera

    DEFF Research Database (Denmark)

    Lukjancenko, Oksana; Ussery, David; Wassenaar, Trudy M.

    2012-01-01

    Six bacterial genera containing species commonly used as probiotics for human consumption or starter cultures for food fermentation were compared and contrasted, based on publicly available complete genome sequences. The analysis included 19 Bifidobacterium genomes, 21 Lactobacillus genomes, 4...

  19. Comparative genomics and evolution of eukaryotic phospholipidbiosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Lykidis, Athanasios

    2006-12-01

    Phospholipid biosynthetic enzymes produce diverse molecular structures and are often present in multiple forms encoded by different genes. This work utilizes comparative genomics and phylogenetics for exploring the distribution, structure and evolution of phospholipid biosynthetic genes and pathways in 26 eukaryotic genomes. Although the basic structure of the pathways was formed early in eukaryotic evolution, the emerging picture indicates that individual enzyme families followed unique evolutionary courses. For example, choline and ethanolamine kinases and cytidylyltransferases emerged in ancestral eukaryotes, whereas, multiple forms of the corresponding phosphatidyltransferases evolved mainly in a lineage specific manner. Furthermore, several unicellular eukaryotes maintain bacterial-type enzymes and reactions for the synthesis of phosphatidylglycerol and cardiolipin. Also, base-exchange phosphatidylserine synthases are widespread and ancestral enzymes. The multiplicity of phospholipid biosynthetic enzymes has been largely generated by gene expansion in a lineage specific manner. Thus, these observations suggest that phospholipid biosynthesis has been an actively evolving system. Finally, comparative genomic analysis indicates the existence of novel phosphatidyltransferases and provides a candidate for the uncharacterized eukaryotic phosphatidylglycerol phosphate phosphatase.

  20. Comparative Genomics of Ten Solanaceous Plastomes

    Directory of Open Access Journals (Sweden)

    Harpreet Kaur

    2014-01-01

    Full Text Available Availability of complete plastid genomes of ten solanaceous species, Atropa belladonna, Capsicum annuum, Datura stramonium, Nicotiana sylvestris, Nicotiana tabacum, Nicotiana tomentosiformis, Nicotiana undulata, Solanum bulbocastanum, Solanum lycopersicum, and Solanum tuberosum provided us with an opportunity to conduct their in silico comparative analysis in depth. The size of complete chloroplast genomes and LSC and SSC regions of three species of Solanum is comparatively smaller than that of any other species studied till date (exception: SSC region of A. belladonna. AT content of coding regions was found to be less than noncoding regions. A duplicate copy of trnH gene in C. annuum and two alternative tRNA genes for proline in D. stramonium were observed for the first time in this analysis. Further, homology search revealed the presence of rps19 pseudogene and infA genes in A. belladonna and D. stramonium, a region identical to rps19 pseudogene in C. annum and orthologues of sprA gene in another six species. Among the eighteen intron-containing genes, 3 genes have two introns and 15 genes have one intron. The longest insertion was found in accD gene in C. annuum. Phylogenetic analysis using concatenated protein coding sequences gave two clades, one for Nicotiana species and another for Solanum, Capsicum, Atropa, and Datura.

  1. Comparative genomics of emerging human ehrlichiosis agents.

    Directory of Open Access Journals (Sweden)

    Julie C Dunning Hotopp

    2006-02-01

    Full Text Available Anaplasma (formerly Ehrlichia phagocytophilum, Ehrlichia chaffeensis, and Neorickettsia (formerly Ehrlichia sennetsu are intracellular vector-borne pathogens that cause human ehrlichiosis, an emerging infectious disease. We present the complete genome sequences of these organisms along with comparisons to other organisms in the Rickettsiales order. Ehrlichia spp. and Anaplasma spp. display a unique large expansion of immunodominant outer membrane proteins facilitating antigenic variation. All Rickettsiales have a diminished ability to synthesize amino acids compared to their closest free-living relatives. Unlike members of the Rickettsiaceae family, these pathogenic Anaplasmataceae are capable of making all major vitamins, cofactors, and nucleotides, which could confer a beneficial role in the invertebrate vector or the vertebrate host. Further analysis identified proteins potentially involved in vacuole confinement of the Anaplasmataceae, a life cycle involving a hematophagous vector, vertebrate pathogenesis, human pathogenesis, and lack of transovarial transmission. These discoveries provide significant insights into the biology of these obligate intracellular pathogens.

  2. Comparative genomics reveals insights into avian genome evolution and adaptation

    DEFF Research Database (Denmark)

    Zhang, Guojie; Li, Cai; Li, Qiye

    2014-01-01

    Birds are the most species-rich class of tetrapod vertebrates and have wide relevance across many research fields. We explored bird macroevolution using full genomes from 48 avian species representing all major extant clades. The avian genome is principally characterized by its constrained size, ...

  3. The bonobo genome compared with the chimpanzee and human genomes.

    Science.gov (United States)

    Prüfer, Kay; Munch, Kasper; Hellmann, Ines; Akagi, Keiko; Miller, Jason R; Walenz, Brian; Koren, Sergey; Sutton, Granger; Kodira, Chinnappa; Winer, Roger; Knight, James R; Mullikin, James C; Meader, Stephen J; Ponting, Chris P; Lunter, Gerton; Higashino, Saneyuki; Hobolth, Asger; Dutheil, Julien; Karakoç, Emre; Alkan, Can; Sajjadian, Saba; Catacchio, Claudia Rita; Ventura, Mario; Marques-Bonet, Tomas; Eichler, Evan E; André, Claudine; Atencia, Rebeca; Mugisha, Lawrence; Junhold, Jörg; Patterson, Nick; Siebauer, Michael; Good, Jeffrey M; Fischer, Anne; Ptak, Susan E; Lachmann, Michael; Symer, David E; Mailund, Thomas; Schierup, Mikkel H; Andrés, Aida M; Kelso, Janet; Pääbo, Svante

    2012-06-28

    Two African apes are the closest living relatives of humans: the chimpanzee (Pan troglodytes) and the bonobo (Pan paniscus). Although they are similar in many respects, bonobos and chimpanzees differ strikingly in key social and sexual behaviours, and for some of these traits they show more similarity with humans than with each other. Here we report the sequencing and assembly of the bonobo genome to study its evolutionary relationship with the chimpanzee and human genomes. We find that more than three per cent of the human genome is more closely related to either the bonobo or the chimpanzee genome than these are to each other. These regions allow various aspects of the ancestry of the two ape species to be reconstructed. In addition, many of the regions that overlap genes may eventually help us understand the genetic basis of phenotypes that humans share with one of the two apes to the exclusion of the other.

  4. The bonobo genome compared with the chimpanzee and human genomes

    Science.gov (United States)

    Prüfer, Kay; Munch, Kasper; Hellmann, Ines; Akagi, Keiko; Miller, Jason R.; Walenz, Brian; Koren, Sergey; Sutton, Granger; Kodira, Chinnappa; Winer, Roger; Knight, James R.; Mullikin, James C.; Meader, Stephen J.; Ponting, Chris P.; Lunter, Gerton; Higashino, Saneyuki; Hobolth, Asger; Dutheil, Julien; Karakoç, Emre; Alkan, Can; Sajjadian, Saba; Catacchio, Claudia Rita; Ventura, Mario; Marques-Bonet, Tomas; Eichler, Evan E.; André, Claudine; Atencia, Rebeca; Mugisha, Lawrence; Junhold, Jörg; Patterson, Nick; Siebauer, Michael; Good, Jeffrey M.; Fischer, Anne; Ptak, Susan E.; Lachmann, Michael; Symer, David E.; Mailund, Thomas; Schierup, Mikkel H.; Andrés, Aida M.; Kelso, Janet; Pääbo, Svante

    2012-01-01

    Two African apes are the closest living relatives of humans: the chimpanzee (Pan troglodytes) and the bonobo (Pan paniscus). Although they are similar in many respects, bonobos and chimpanzees differ strikingly in key social and sexual behaviours1–4, and for some of these traits they show more similarity with humans than with each other. Here we report the sequencing and assembly of the bonobo genome to study its evolutionary relationship with the chimpanzee and human genomes. We find that more than three per cent of the human genome is more closely related to either the bonobo or the chimpanzee genome than these are to each other. These regions allow various aspects of the ancestry of the two ape species to be reconstructed. In addition, many of the regions that overlap genes may eventually help us understand the genetic basis of phenotypes that humans share with one of the two apes to the exclusion of the other. PMID:22722832

  5. Comparing genetic variants detected in the 1000 genomes project with SNPs determined by the International HapMap Consortium.

    Science.gov (United States)

    Zhang, Wenqian; Ng, Hui Wen; Shu, Mao; Luo, Heng; Su, ZhenQiang; Ge, Weigong; Perkins, Roger; Tong, Weida; Hong, Huixiao

    2015-12-01

    Single-nucleotide polymorphisms (SNPs) determined based on SNP arrays from the international HapMap consortium (HapMap) and the genetic variants detected in the 1000 genomes project (1KGP) can serve as two references for genomewide association studies (GWAS). We conducted comparative analyses to provide a means for assessing concerns regarding SNP array-based GWAS findings as well as for realistically bounding expectations for next generation sequencing (NGS)-based GWAS. We calculated and compared base composition, transitions to transversions ratio, minor allele frequency and heterozygous rate for SNPs from HapMap and 1KGP for the 622 common individuals. We analysed the genotype discordance between HapMap and 1KGP to assess consistency in the SNPs from the two references. In 1KGP, 90.58% of 36,817,799 SNPs detected were not measured in HapMap. More SNPs with minor allele frequencies less than 0.01 were found in 1KGP than HapMap. The two references have low disc ordance (generally smaller than 0.02) in genotypes of common SNPs, with most discordance from heterozygous SNPs. Our study demonstrated that SNP array-based GWAS findings were reliable and useful, although only a small portion of genetic variances were explained. NGS can detect not only common but also rare variants, supporting the expectation that NGS-based GWAS will be able to incorporate a much larger portion of genetic variance than SNP arrays-based GWAS.

  6. Evaluation of Apis mellifera syriaca Levant region honeybee conservation using comparative genome hybridization.

    Science.gov (United States)

    Haddad, Nizar Jamal; Batainh, Ahmed; Saini, Deepti; Migdadi, Osama; Aiyaz, Mohamed; Manchiganti, Rushiraj; Krishnamurthy, Venkatesh; Al-Shagour, Banan; Brake, Mohammad; Bourgeois, Lelania; De Guzman, Lilia; Rinderer, Thomas; Hamouri, Zayed Mahoud

    2016-06-01

    Apis mellifera syriaca is the native honeybee subspecies of Jordan and much of the Levant region. It expresses behavioral adaptations to a regional climate with very high temperatures, nectar dearth in summer, attacks of the Oriental wasp and is resistant to Varroa mites. The A. m. syriaca control reference sample (CRS) in this study was originally collected and stored since 2001 from "Wadi Ben Hammad", a remote valley in the southern region of Jordan. Morphometric and mitochondrial DNA markers of these honeybees had shown highest similarity to reference A. m. syriaca samples collected in 1952 by Brother Adam of samples collected from the Middle East. Samples 1-5 were collected from the National Center for Agricultural Research and Extension breeding apiary which was established for the conservation of A. m. syriaca. Our objective was to determine the success of an A. m. syriaca honey bee conservation program using genomic information from an array-based comparative genomic hybridization platform to evaluate genetic similarities to a historic reference collection (CRS). Our results had shown insignificant genomic differences between the current population in the conservation program and the CRS indicated that program is successfully conserving A. m. syriaca. Functional genomic variations were identified which are useful for conservation monitoring and may be useful for breeding programs designed to improve locally adapted strains of A. m. syriaca.

  7. Circos: an information aesthetic for comparative genomics.

    Science.gov (United States)

    Krzywinski, Martin; Schein, Jacqueline; Birol, Inanç; Connors, Joseph; Gascoyne, Randy; Horsman, Doug; Jones, Steven J; Marra, Marco A

    2009-09-01

    We created a visualization tool called Circos to facilitate the identification and analysis of similarities and differences arising from comparisons of genomes. Our tool is effective in displaying variation in genome structure and, generally, any other kind of positional relationships between genomic intervals. Such data are routinely produced by sequence alignments, hybridization arrays, genome mapping, and genotyping studies. Circos uses a circular ideogram layout to facilitate the display of relationships between pairs of positions by the use of ribbons, which encode the position, size, and orientation of related genomic elements. Circos is capable of displaying data as scatter, line, and histogram plots, heat maps, tiles, connectors, and text. Bitmap or vector images can be created from GFF-style data inputs and hierarchical configuration files, which can be easily generated by automated tools, making Circos suitable for rapid deployment in data analysis and reporting pipelines.

  8. Comparative genomic hybridization in clinical cytogenetics

    Energy Technology Data Exchange (ETDEWEB)

    Bryndorf, T.; Kirchhoff, M.; Rose, H. [and others

    1995-11-01

    We report the results of applying comparative genomic hybridization (CGH) in a cytogenetic service laboratory for (1) determination of the origin of extra and missing chromosomal material in intricate cases of unbalanced aberrations and (2) detection of common prenatal numerical chromosome aberrations. A total of 11 fetal samples were analyzed. Seven cases of complex unbalanced aberrations that could not be identified reliably by conventional cytogenetics were successfully resolved by CGH analysis. CGH results were validated by using FISH with chromosome-specific probes. Four cases representing common prenatal numerical aberrations (trisomy 21, 18, and 13 and monosomy X) were also successfully diagnosed by CGH. We conclude that CGH is a powerful adjunct to traditional cytogenetic techniques that makes it possible to solve clinical cases of intricate unbalanced aberrations in a single hybridization. CGH may also be a useful adjunct to screen for euchromatic involvement in marker chromosomes. Further technical development may render CGH applicable for routine aberration screening. 16 refs., 4 figs., 2 tabs.

  9. Genomic profiling of plasmablastic lymphoma using array comparative genomic hybridization (aCGH: revealing significant overlapping genomic lesions with diffuse large B-cell lymphoma

    Directory of Open Access Journals (Sweden)

    Lu Xin-Yan

    2009-11-01

    Full Text Available Abstract Background Plasmablastic lymphoma (PL is a subtype of diffuse large B-cell lymphoma (DLBCL. Studies have suggested that tumors with PL morphology represent a group of neoplasms with clinopathologic characteristics corresponding to different entities including extramedullary plasmablastic tumors associated with plasma cell myeloma (PCM. The goal of the current study was to evaluate the genetic similarities and differences among PL, DLBCL (AIDS-related and non AIDS-related and PCM using array-based comparative genomic hybridization. Results Examination of genomic data in PL revealed that the most frequent segmental gain (> 40% include: 1p36.11-1p36.33, 1p34.1-1p36.13, 1q21.1-1q23.1, 7q11.2-7q11.23, 11q12-11q13.2 and 22q12.2-22q13.3. This correlated with segmental gains occurring in high frequency in DLBCL (AIDS-related and non AIDS-related cases. There were some segmental gains and some segmental loss that occurred in PL but not in the other types of lymphoma suggesting that these foci may contain genes responsible for the differentiation of this lymphoma. Additionally, some segmental gains and some segmental loss occurred only in PL and AIDS associated DLBCL suggesting that these foci may be associated with HIV infection. Furthermore, some segmental gains and some segmental loss occurred only in PL and PCM suggesting that these lesions may be related to plasmacytic differentiation. Conclusion To the best of our knowledge, the current study represents the first genomic exploration of PL. The genomic aberration pattern of PL appears to be more similar to that of DLBCL (AIDS-related or non AIDS-related than to PCM. Our findings suggest that PL may remain best classified as a subtype of DLBCL at least at the genome level.

  10. An evaluation of Comparative Genome Sequencing (CGS by comparing two previously-sequenced bacterial genomes

    Directory of Open Access Journals (Sweden)

    Herring Christopher D

    2007-08-01

    Full Text Available Abstract Background With the development of new technology, it has recently become practical to resequence the genome of a bacterium after experimental manipulation. It is critical though to know the accuracy of the technique used, and to establish confidence that all of the mutations were detected. Results In order to evaluate the accuracy of genome resequencing using the microarray-based Comparative Genome Sequencing service provided by Nimblegen Systems Inc., we resequenced the E. coli strain W3110 Kohara using MG1655 as a reference, both of which have been completely sequenced using traditional sequencing methods. CGS detected 7 of 8 small sequence differences, one large deletion, and 9 of 12 IS element insertions present in W3110, but did not detect a large chromosomal inversion. In addition, we confirmed that CGS also detected 2 SNPs, one deletion and 7 IS element insertions that are not present in the genome sequence, which we attribute to changes that occurred after the creation of the W3110 lambda clone library. The false positive rate for SNPs was one per 244 Kb of genome sequence. Conclusion CGS is an effective way to detect multiple mutations present in one bacterium relative to another, and while highly cost-effective, is prone to certain errors. Mutations occurring in repeated sequences or in sequences with a high degree of secondary structure may go undetected. It is also critical to follow up on regions of interest in which SNPs were not called because they often indicate deletions or IS element insertions.

  11. Comparative Genomics of Symbiotic Bacteria in Earthworm Nephridia

    DEFF Research Database (Denmark)

    Kjeldsen, Kasper Urup; Pinel, Nicolas; Lund, Marie Braad;

    excretion products. Gene order was highly conserved between the genomes of Acidovorax avena and Acidovorax sp. JS42, whereas the E. fetida symbiont genome held very little conservation of gene order compared to either of the latter two. Repetitive sequences were excessively abundant throughout the genomes...

  12. Human and mouse genome analysis using array comparative genomic hybridization

    NARCIS (Netherlands)

    Snijders, Antoine Maria

    2004-01-01

    Almost all human cancers as well as developmental abnormalities are characterized by the presence of genetic alterations, most of which target a gene or a particular genomic locus resulting in altered gene expression and ultimately an altered phenotype. Different types of genetic alterations include

  13. Genome-wide mapping of copy number variation in humans: comparative analysis of high resolution array platforms.

    Directory of Open Access Journals (Sweden)

    Rajini R Haraksingh

    Full Text Available Accurate and efficient genome-wide detection of copy number variants (CNVs is essential for understanding human genomic variation, genome-wide CNV association type studies, cytogenetics research and diagnostics, and independent validation of CNVs identified from sequencing based technologies. Numerous, array-based platforms for CNV detection exist utilizing array Comparative Genome Hybridization (aCGH, Single Nucleotide Polymorphism (SNP genotyping or both. We have quantitatively assessed the abilities of twelve leading genome-wide CNV detection platforms to accurately detect Gold Standard sets of CNVs in the genome of HapMap CEU sample NA12878, and found significant differences in performance. The technologies analyzed were the NimbleGen 4.2 M, 2.1 M and 3×720 K Whole Genome and CNV focused arrays, the Agilent 1×1 M CGH and High Resolution and 2×400 K CNV and SNP+CGH arrays, the Illumina Human Omni1Quad array and the Affymetrix SNP 6.0 array. The Gold Standards used were a 1000 Genomes Project sequencing-based set of 3997 validated CNVs and an ultra high-resolution aCGH-based set of 756 validated CNVs. We found that sensitivity, total number, size range and breakpoint resolution of CNV calls were highest for CNV focused arrays. Our results are important for cost effective CNV detection and validation for both basic and clinical applications.

  14. Phytozome: a comparative platform for green plant genomics

    OpenAIRE

    Goodstein, David M.; Shu, Shengqiang; Howson, Russell; Neupane, Rochak; Hayes, Richard D.; Fazo, Joni; Mitros, Therese; Dirks, William; Hellsten, Uffe; Putnam, Nicholas ; Rokhsar, Daniel S.

    2011-01-01

    The number of sequenced plant genomes and associated genomic resources is growing rapidly with the advent of both an increased focus on plant genomics from funding agencies, and the application of inexpensive next generation sequencing. To interact with this increasing body of data, we have developed Phytozome (http://www.phytozome.net), a comparative hub for plant genome and gene family data and analysis. Phytozome provides a view of the evolutionary history of every plant gene at the level ...

  15. Using comparative genomic hybridization to survey genomic sequence divergence across species: a proof-of-concept from Drosophila

    Directory of Open Access Journals (Sweden)

    Kulathinal Rob J

    2010-04-01

    Full Text Available Abstract Background Genome-wide analysis of sequence divergence among species offers profound insights into the evolutionary processes that shape lineages. When full-genome sequencing is not feasible for a broad comparative study, we propose the use of array-based comparative genomic hybridization (aCGH in order to identify orthologous genes with high sequence divergence. Here we discuss experimental design, statistical power, success rate, sources of variation and potential confounding factors. We used a spotted PCR product microarray platform from Drosophila melanogaster to assess sequence divergence on a gene-by-gene basis in three fully sequenced heterologous species (D. sechellia, D. simulans, and D. yakuba. Because complete genome assemblies are available for these species this study presents a powerful test for the use of aCGH as a tool to measure sequence divergence. Results We found a consistent and linear relationship between hybridization ratio and sequence divergence of the sample to the platform species. At higher levels of sequence divergence (D. melanogaster ~84% of features had significantly less hybridization to the array in the heterologous species than the platform species, and thus could be identified as "diverged". At lower levels of divergence (≥ 97% identity, only 13% of genes were identified as diverged. While ~40% of the variation in hybridization ratio can be accounted for by variation in sequence identity of the heterologous sample relative to D. melanogaster, other individual characteristics of the DNA sequences, such as GC content, also contribute to variation in hybridization ratio, as does technical variation. Conclusions Here we demonstrate that aCGH can accurately be used as a proxy to estimate genome-wide divergence, thus providing an efficient way to evaluate how evolutionary processes and genomic architecture can shape species diversity in non-model systems. Given the increased number of species for which

  16. Comparative genomic hybridization: Detection of segmental aneusomies

    Energy Technology Data Exchange (ETDEWEB)

    Cronin, J.E.; Magrane, G.G.; Gray, J.W. [Univ. of California, San Francisco, CA (United States)] [and others

    1994-09-01

    Comparative genomic hybridization (CGH) has been used successfully to detect whole chromosome and segmental aneusomies. However, its sensitivity for detection of segmental aneusomies is still not well known. We present here an analysis of CGH sensitivity with emphasis on detection of abnormalities commonly found during pre-and neo-natal diagnosis. CGH is performed by hybridizing green and red fluorescing test and normal DNA samples, respectively, to normal metaphase spreads and measuring green:red fluorescence ratios along all chromosomes. The ratios are normalized such that 2 copies of a normal chromosome region in the test sample gives a ratio of 1.0. Alterations in test vs. control gene copy number range from 1.5 [trisomy] to 0.5 [monosomy]. Clinical samples analyzed included Wolf Hirschhorn (4p-), Cri du Chat (5p-) and DiGeorge (22q-). In addition, 7 cell lines with chromosome 21 segmental aneusomies were analyzed. These included 3 with terminal duplications, 1 with a terminal deletion, 1 with an interstitial deletion and 2 with interstitial amplifications. The DiGeorge deletion was the only deletion not deleted by CGH. This is not surprising as standard G banding does not routinely detect this 1-2 megabase deletion. The 4p- and 5p- monosomies were detected and breakpoints correctly assigned prospectively. Proximal alterations involving 21q22.11 are unambiguously defined. Specifically, two interstitial aneusomies involving this region are detected. Studies involving late prophase chromosome normal spreads gave identical breakpoints. Thus, analysis of extended chromosomes did not improve the sensitivity of the technique. Taken together, these data suggest that CGH can detect segmental aneusomies greater than 8 megabases in extent. Smaller aneusomies can, at times, be detected. Work is now underway to modify the analysis software to increase sensitivity and to decrease the amount of material needed for analysis.

  17. 3D Genome Tuner: Compare Multiple Circular Genomes in a 3D Context

    Institute of Scientific and Technical Information of China (English)

    Qi Wang; Qun Liang; Xiuqing Zhang

    2009-01-01

    Circular genomes, being the largest proportion of sequenced genomes, play an important role in genome analysis. However, traditional 2D circular map only provides an overview and annotations of genome but does not offer feature-based comparison. For remedying these shortcomings, we developed 3D Genome Tuner, a hybrid of circular map and comparative map tools. Its capability of viewing comparisons between multiple circular maps in a 3D space offers great benefits to the study of comparative genomics. The program is freely available(under an LGPL licence)at http://sourceforge.net/projects/dgenometuner.

  18. Comparative genomics and genome biology of invasive Campylobacter jejuni.

    Science.gov (United States)

    Skarp, C P A; Akinrinade, O; Nilsson, A J E; Ellström, P; Myllykangas, S; Rautelin, H

    2015-11-25

    Campylobacter jejuni is a major pathogen in bacterial gastroenteritis worldwide and can cause bacteremia in severe cases. C. jejuni is highly structured into clonal lineages of which the ST677CC lineage has been overrepresented among C. jejuni isolates derived from blood. In this study, we characterized the genomes of 31 C. jejuni blood isolates and 24 faecal isolates belonging to ST677CC in order to study the genome biology related to C. jejuni invasiveness. We combined the genome analyses with phenotypical evidence on serum resistance which was associated with phase variation of wcbK; a GDP-mannose 4,6-dehydratase involved in capsular biosynthesis. We also describe the finding of a Type III restriction-modification system unique to the ST-794 sublineage. However, features previously considered to be related to pathogenesis of C. jejuni were either absent or disrupted among our strains. Our results refine the role of capsule features associated with invasive disease and accentuate the possibility of methylation and restriction enzymes in the potential of C. jejuni to establish invasive infections. Our findings underline the importance of studying clinically relevant well-characterized bacterial strains in order to understand pathogenesis mechanisms important in human infections.

  19. Comparative genomics of Cluster O mycobacteriophages.

    Directory of Open Access Journals (Sweden)

    Steven G Cresawn

    Full Text Available Mycobacteriophages--viruses of mycobacterial hosts--are genetically diverse but morphologically are all classified in the Caudovirales with double-stranded DNA and tails. We describe here a group of five closely related mycobacteriophages--Corndog, Catdawg, Dylan, Firecracker, and YungJamal--designated as Cluster O with long flexible tails but with unusual prolate capsids. Proteomic analysis of phage Corndog particles, Catdawg particles, and Corndog-infected cells confirms expression of half of the predicted gene products and indicates a non-canonical mechanism for translation of the Corndog tape measure protein. Bioinformatic analysis identifies 8-9 strongly predicted SigA promoters and all five Cluster O genomes contain more than 30 copies of a 17 bp repeat sequence with dyad symmetry located throughout the genomes. Comparison of the Cluster O phages provides insights into phage genome evolution including the processes of gene flux by horizontal genetic exchange.

  20. Characterization of hemizygous deletions in Citrus using array-Comparative Genomic Hybridization and microsynteny comparisons with the poplar genome

    Directory of Open Access Journals (Sweden)

    Usach Antonio

    2008-08-01

    Full Text Available Abstract Background Many fruit-tree species, including relevant Citrus spp varieties exhibit a reproductive biology that impairs breeding and strongly constrains genetic improvements. In citrus, juvenility increases the generation time while sexual sterility, inbreeding depression and self-incompatibility prevent the production of homozygous cultivars. Genomic technology may provide citrus researchers with a new set of tools to address these various restrictions. In this work, we report a valuable genomics-based protocol for the structural analysis of deletion mutations on an heterozygous background. Results Two independent fast neutron mutants of self-incompatible clementine (Citrus clementina Hort. Ex Tan. cv. Clemenules were the subject of the study. Both mutants, named 39B3 and 39E7, were expected to carry DNA deletions in hemizygous dosage. Array-based Comparative Genomic Hybridization (array-CGH using a Citrus cDNA microarray allowed the identification of underrepresented genes in these two mutants. Subsequent comparison of citrus deleted genes with annotated plant genomes, especially poplar, made possible to predict the presence of a large deletion in 39B3 of about 700 kb and at least two deletions of approximately 100 and 500 kb in 39E7. The deletion in 39B3 was further characterized by PCR on available Citrus BACs, which helped us to build a partial physical map of the deletion. Among the deleted genes, ClpC-like gene coding for a putative subunit of a multifunctional chloroplastic protease involved in the regulation of chlorophyll b synthesis was directly related to the mutated phenotype since the mutant showed a reduced chlorophyll a/b ratio in green tissues. Conclusion In this work, we report the use of array-CGH for the successful identification of genes included in a hemizygous deletion induced by fast neutron irradiation on Citrus clementina. The study of gene content and order into the 39B3 deletion also led to the unexpected

  1. Comparative and functional genomics reveals genetic diversity and determinants of host specificity among reference strains and a large collection of Chinese isolates of the phytopathogen Xanthomonas campestris pv. campestris

    OpenAIRE

    He, Yong-Qiang; Zhang, Liang; Jiang, Bo-Le; Zhang, Zheng-Chun; Xu, Rong-Qi; Tang, Dong-Jie; Qin, Jing; Jiang, Wei; Zhang, Xia; LIAO, JIE; Cao, Jin-Ru; Zhang, Sui-Sheng; Wei, Mei-Liang; Liang, Xiao-Xia; Lu, Guang-Tao

    2007-01-01

    Background Xanthomonas campestris pathovar campestris (Xcc) is the causal agent of black rot disease of crucifers worldwide. The molecular genetic diversity and host specificity of Xcc are poorly understood. Results We constructed a microarray based on the complete genome sequence of Xcc strain 8004 and investigated the genetic diversity and host specificity of Xcc by array-based comparative genome hybridization analyses of 18 virulent strains. The results demonstrate that a genetic core comp...

  2. Gene family assignment-free comparative genomics

    Directory of Open Access Journals (Sweden)

    Doerr Daniel

    2012-12-01

    Full Text Available Abstract Background The comparison of relative gene orders between two genomes offers deep insights into functional correlations of genes and the evolutionary relationships between the corresponding organisms. Methods for gene order analyses often require prior knowledge of homologies between all genes of the genomic dataset. Since such information is hard to obtain, it is common to predict homologous groups based on sequence similarity. These hypothetical groups of homologous genes are called gene families. Results This manuscript promotes a new branch of gene order studies in which prior assignment of gene families is not required. As a case study, we present a new similarity measure between pairs of genomes that is related to the breakpoint distance. We propose an exact and a heuristic algorithm for its computation. We evaluate our methods on a dataset comprising 12 γ-proteobacteria from the literature. Conclusions In evaluating our algorithms, we show that the exact algorithm is suitable for computations on small genomes. Moreover, the results of our heuristic are close to those of the exact algorithm. In general, we demonstrate that gene order studies can be improved by direct, gene family assignment-free comparisons.

  3. Comparative genomics of the Bifidobacterium breve taxon

    NARCIS (Netherlands)

    Bottacini, Francesca; O'Connell Motherway, Mary; Kuczynski, Justin; O'Connell, Kerry Joan; Serafini, Fausta; Duranti, Sabrina; Milani, Christian; Turroni, Francesca; Lugli, Gabriele Andrea; Zomer, Aldert; Zhurina, Daria; Riedel, Christian; Ventura, Marco; van Sinderen, Douwe

    2014-01-01

    BACKGROUND: Bifidobacteria are commonly found as part of the microbiota of the gastrointestinal tract (GIT) of a broad range of hosts, where their presence is positively correlated with the host's health status. In this study, we assessed the genomes of thirteen representatives of Bifidobacterium br

  4. Whole genome comparative studies between chicken and turkey and their implications for avian genome evolution

    NARCIS (Netherlands)

    Griffin, D.K.; Robertson, L.B.; Tempest, H.G.; Vignal, A.; Fillon, V.; Crooijmans, R.P.M.A.; Groenen, M.A.M.; Deryusheva, S.; Gaginskaya, E.; Carre, W.; Waddington, D.; Talbot, R.; Völker, M.; Masabanda, J.S.; Burt, D.W.

    2008-01-01

    Background Comparative genomics is a powerful means of establishing inter-specific relationships between gene function/location and allows insight into genomic rearrangements, conservation and evolutionary phylogeny. The availability of the complete sequence of the chicken genome has initiated the d

  5. Comparative genomics of the lactic acid bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Makarova, K.; Slesarev, A.; Wolf, Y.; Sorokin, A.; Mirkin, B.; Koonin, E.; Pavlov, A.; Pavlova, N.; Karamychev, V.; Polouchine, N.; Shakhova, V.; Grigoriev, I.; Lou, Y.; Rokhsar, D.; Lucas, S.; Huang, K.; Goodstein, D. M.; Hawkins, T.; Plengvidhya, V.; Welker, D.; Hughes, J.; Goh, Y.; Benson, A.; Baldwin, K.; Lee, J. -H.; Diaz-Muniz, I.; Dosti, B.; Smeianov, V; Wechter, W.; Barabote, R.; Lorca, G.; Altermann, E.; Barrangou, R.; Ganesan, B.; Xie, Y.; Rawsthorne, H.; Tamir, D.; Parker, C.; Breidt, F.; Broadbent, J.; Hutkins, R.; O' Sullivan, D.; Steele, J.; Unlu, G.; Saier, M.; Klaenhammer, T.; Richardson, P.; Kozyavkin, S.; Weimer, B.; Mills, D.

    2006-06-01

    Lactic acid-producing bacteria are associated with various plant and animal niches and play a key role in the production of fermented foods and beverages. We report nine genome sequences representing the phylogenetic and functional diversity of these bacteria. The small genomes of lactic acid bacteria encode a broad repertoire of transporters for efficient carbon and nitrogen acquisition from the nutritionally rich environments they inhabit and reflect a limited range of biosynthetic capabilities that indicate both prototrophic and auxotrophic strains. Phylogenetic analyses, comparison of gene content across the group, and reconstruction of ancestral gene sets indicate a combination of extensive gene loss and key gene acquisitions via horizontal gene transfer during the coevolution of lactic acid bacteria with their habitats.

  6. Human-mouse comparative genomics: successes and failures to reveal functional regions of the human genome

    Energy Technology Data Exchange (ETDEWEB)

    Pennacchio, Len A.; Baroukh, Nadine; Rubin, Edward M.

    2003-05-15

    Deciphering the genetic code embedded within the human genome remains a significant challenge despite the human genome consortium's recent success at defining its linear sequence (Lander et al. 2001; Venter et al. 2001). While useful strategies exist to identify a large percentage of protein encoding regions, efforts to accurately define functional sequences in the remaining {approx}97 percent of the genome lag. Our primary interest has been to utilize the evolutionary relationship and the universal nature of genomic sequence information in vertebrates to reveal functional elements in the human genome. This has been achieved through the combined use of vertebrate comparative genomics to pinpoint highly conserved sequences as candidates for biological activity and transgenic mouse studies to address the functionality of defined human DNA fragments. Accordingly, we describe strategies and insights into functional sequences in the human genome through the use of comparative genomics coupled wit h functional studies in the mouse.

  7. Comparative genomic analysis of soybean flowering genes.

    Directory of Open Access Journals (Sweden)

    Chol-Hee Jung

    Full Text Available Flowering is an important agronomic trait that determines crop yield. Soybean is a major oilseed legume crop used for human and animal feed. Legumes have unique vegetative and floral complexities. Our understanding of the molecular basis of flower initiation and development in legumes is limited. Here, we address this by using a computational approach to examine flowering regulatory genes in the soybean genome in comparison to the most studied model plant, Arabidopsis. For this comparison, a genome-wide analysis of orthologue groups was performed, followed by an in silico gene expression analysis of the identified soybean flowering genes. Phylogenetic analyses of the gene families highlighted the evolutionary relationships among these candidates. Our study identified key flowering genes in soybean and indicates that the vernalisation and the ambient-temperature pathways seem to be the most variant in soybean. A comparison of the orthologue groups containing flowering genes indicated that, on average, each Arabidopsis flowering gene has 2-3 orthologous copies in soybean. Our analysis highlighted that the CDF3, VRN1, SVP, AP3 and PIF3 genes are paralogue-rich genes in soybean. Furthermore, the genome mapping of the soybean flowering genes showed that these genes are scattered randomly across the genome. A paralogue comparison indicated that the soybean genes comprising the largest orthologue group are clustered in a 1.4 Mb region on chromosome 16 of soybean. Furthermore, a comparison with the undomesticated soybean (Glycine soja revealed that there are hundreds of SNPs that are associated with putative soybean flowering genes and that there are structural variants that may affect the genes of the light-signalling and ambient-temperature pathways in soybean. Our study provides a framework for the soybean flowering pathway and insights into the relationship and evolution of flowering genes between a short-day soybean and the long-day plant

  8. Comparative genomics using data mining tools

    Indian Academy of Sciences (India)

    Tannistha Nandi; Chandrika B-Rao; Srinivasan Ramachandran

    2002-02-01

    We have analysed the genomes of representatives of three kingdoms of life, namely, archaea, eubacteria and eukaryota using data mining tools based on compositional analyses of the protein sequences. The representatives chosen in this analysis were Methanococcus jannaschii, Haemophilus influenzae and Saccharomyces cerevisiae. We have identified the common and different features between the three genomes in the protein evolution patterns. M. jannaschii has been seen to have a greater number of proteins with more charged amino acids whereas S. cerevisiae has been observed to have a greater number of hydrophilic proteins. Despite the differences in intrinsic compositional characteristics between the proteins from the different genomes we have also identified certain common characteristics. We have carried out exploratory Principal Component Analysis of the multivariate data on the proteins of each organism in an effort to classify the proteins into clusters. Interestingly, we found that most of the proteins in each organism cluster closely together, but there are a few ‘outliers’. We focus on the outliers for the functional investigations, which may aid in revealing any unique features of the biology of the respective organisms.

  9. AcCNET (Accessory Genome Constellation Network): comparative genomics software for accessory genome analysis using bipartite networks.

    Science.gov (United States)

    Lanza, Val F; Baquero, Fernando; de la Cruz, Fernando; Coque, Teresa M

    2017-01-15

    AcCNET (Accessory genome Constellation Network) is a Perl application that aims to compare accessory genomes of a large number of genomic units, both at qualitative and quantitative levels. Using the proteomes extracted from the analysed genomes, AcCNET creates a bipartite network compatible with standard network analysis platforms. AcCNET allows merging phylogenetic and functional information about the concerned genomes, thus improving the capability of current methods of network analysis. The AcCNET bipartite network opens a new perspective to explore the pangenome of bacterial species, focusing on the accessory genome behind the idiosyncrasy of a particular strain and/or population.

  10. Comparative genome analysis of Bacillus cereus group genomes with Bacillus subtilis

    OpenAIRE

    Anderson, Iain; Sorokin, Alexei; Kapatral, Vinayak; Reznik, Gary; Bhattacharya, Anamitra; Mikhailova, Natalia; Burd, Henry; Joukov, Victor; Kaznadzey, Denis; Walunas, Theresa; D'Souza, Mark; Larsen, Niels; Pusch, Gordon; Liolios, Konstantinos; Grechkin, Yuri

    2005-01-01

    Genome features of the Bacillus cereus group genomes (representative strains of Bacillus cereus, Bacillus anthracis and Bacillus thuringiensis sub spp israelensis) were analyzed and compared with the Bacillus subtilis genome. A core set of 1,381 protein families among the four Bacillus genomes, with an additional set of 933 families common to the B. cereus group, was identified. Differences in signal transduction pathways, membrane transporters, cell surface structures, cell wall, and S-...

  11. GenColors-based comparative genome databases for small eukaryotic genomes.

    Science.gov (United States)

    Felder, Marius; Romualdi, Alessandro; Petzold, Andreas; Platzer, Matthias; Sühnel, Jürgen; Glöckner, Gernot

    2013-01-01

    Many sequence data repositories can give a quick and easily accessible overview on genomes and their annotations. Less widespread is the possibility to compare related genomes with each other in a common database environment. We have previously described the GenColors database system (http://gencolors.fli-leibniz.de) and its applications to a number of bacterial genomes such as Borrelia, Legionella, Leptospira and Treponema. This system has an emphasis on genome comparison. It combines data from related genomes and provides the user with an extensive set of visualization and analysis tools. Eukaryote genomes are normally larger than prokaryote genomes and thus pose additional challenges for such a system. We have, therefore, adapted GenColors to also handle larger datasets of small eukaryotic genomes and to display eukaryotic gene structures. Further recent developments include whole genome views, genome list options and, for bacterial genome browsers, the display of horizontal gene transfer predictions. Two new GenColors-based databases for two fungal species (http://fgb.fli-leibniz.de) and for four social amoebas (http://sacgb.fli-leibniz.de) were set up. Both new resources open up a single entry point for related genomes for the amoebozoa and fungal research communities and other interested users. Comparative genomics approaches are greatly facilitated by these resources.

  12. Determining and comparing protein function in Bacterial genome sequences

    DEFF Research Database (Denmark)

    Vesth, Tammi Camilla

    In November 2013, there was around 21.000 different prokaryotic genomes sequenced and publicly available, and the number is growing daily with another 20.000 or more genomes expected to be sequenced and deposited by the end of 2014. An important part of the analysis of this data is the functional...... on known functions. This thesis describes the development of new tools for comparative functional annotation and a system for comparative genomics in general. As novel sequenced genomes are becoming more readily available, there is a need for standard analysis tools. The system CMG-biotools is presented...... here as an example of such a system and was used to analyze a set of genomes from the Negativicutes class, a group of bacteria closely related to Gram positives but which has a different cell wall structure and stains Gram negative, as the name indicates. The results of this work show that genomes...

  13. Supervised Lowess normalization of comparative genome hybridization data – application to lactococcal strain comparisons

    Directory of Open Access Journals (Sweden)

    Karsens Harma A

    2008-02-01

    Full Text Available Abstract Background Array-based comparative genome hybridization (aCGH is commonly used to determine the genomic content of bacterial strains. Since prokaryotes in general have less conserved genome sequences than eukaryotes, sequence divergences between the genes in the genomes used for an aCGH experiment obstruct determination of genome variations (e.g. deletions. Current normalization methods do not take into consideration sequence divergence between target and microarray features and therefore cannot distinguish a difference in signal due to systematic errors in the data or due to sequence divergence. Results We present supervised Lowess, or S-Lowess, an application of the subset Lowess normalization method. By using a predicted subset of array features with minimal sequence divergence between the analyzed strains for the normalization procedure we remove systematic errors from dual-dye aCGH data in two steps: (1 determination of a subset of conserved genes (i.e. likely conserved genes, LCG; and (2 using the LCG for subset Lowess normalization. Subset Lowess determines the correction factors for systematic errors in the subset of array features and normalizes all array features using these correction factors. The performance of S-Lowess was assessed on aCGH experiments in which differentially labeled genomic DNA fragments of Lactococcus lactis IL1403 and L. lactis MG1363 strains were hybridized to IL1403 DNA microarrays. Since both genomes are sequenced and gene deletions identified, the success rate of different aCGH normalization methods in detecting these deletions in the MG1363 genome were determined. S-Lowess detects 97% of the deletions, whereas other aCGH normalization methods detect up to only 60% of the deletions. Conclusion S-Lowess is implemented in a user-friendly web-tool accessible from http://bioinformatics.biol.rug.nl/websoftware/s-lowess. We demonstrate that it outperforms existing normalization methods and maximizes

  14. GenoSets: visual analytic methods for comparative genomics.

    Directory of Open Access Journals (Sweden)

    Aurora A Cain

    Full Text Available Many important questions in biology are, fundamentally, comparative, and this extends to our analysis of a growing number of sequenced genomes. Existing genomic analysis tools are often organized around literal views of genomes as linear strings. Even when information is highly condensed, these views grow cumbersome as larger numbers of genomes are added. Data aggregation and summarization methods from the field of visual analytics can provide abstracted comparative views, suitable for sifting large multi-genome datasets to identify critical similarities and differences. We introduce a software system for visual analysis of comparative genomics data. The system automates the process of data integration, and provides the analysis platform to identify and explore features of interest within these large datasets. GenoSets borrows techniques from business intelligence and visual analytics to provide a rich interface of interactive visualizations supported by a multi-dimensional data warehouse. In GenoSets, visual analytic approaches are used to enable querying based on orthology, functional assignment, and taxonomic or user-defined groupings of genomes. GenoSets links this information together with coordinated, interactive visualizations for both detailed and high-level categorical analysis of summarized data. GenoSets has been designed to simplify the exploration of multiple genome datasets and to facilitate reasoning about genomic comparisons. Case examples are included showing the use of this system in the analysis of 12 Brucella genomes. GenoSets software and the case study dataset are freely available at http://genosets.uncc.edu. We demonstrate that the integration of genomic data using a coordinated multiple view approach can simplify the exploration of large comparative genomic data sets, and facilitate reasoning about comparisons and features of interest.

  15. High resolution microarray comparative genomic hybridisation analysis using spotted oligonucleotides.

    NARCIS (Netherlands)

    Carvalho, B; Ouwerkerk, E; Meijer, G.A.; Ylstra, B.

    2004-01-01

    BACKGROUND: Currently, comparative genomic hybridisation array (array CGH) is the method of choice for studying genome wide DNA copy number changes. To date, either amplified representations of bacterial artificial chromosomes (BACs)/phage artificial chromosomes (PACs) or cDNAs have been spotted as

  16. Comparative genomic data of the Avian Phylogenomics Project

    DEFF Research Database (Denmark)

    Zhang, Guojie; Li, Bo; Li, Cai;

    2014-01-01

    , which include 38 newly sequenced avian genomes plus previously released or simultaneously released genomes of Chicken, Zebra finch, Turkey, Pigeon, Peregrine falcon, Duck, Budgerigar, Adelie penguin, Emperor penguin and the Medium Ground Finch. We hope that this resource will serve future efforts...... in an average N50 scaffold size of about 50 kb. Repetitive elements comprised 4%-22% of the bird genomes. The assembled scaffolds allowed the homology-based annotation of 13,000 ~ 17000 protein coding genes in each avian genome relative to chicken, zebra finch and human, as well as comparative and sequence...

  17. Microbial NAD metabolism: lessons from comparative genomics.

    Science.gov (United States)

    Gazzaniga, Francesca; Stebbins, Rebecca; Chang, Sheila Z; McPeek, Mark A; Brenner, Charles

    2009-09-01

    NAD is a coenzyme for redox reactions and a substrate of NAD-consuming enzymes, including ADP-ribose transferases, Sir2-related protein lysine deacetylases, and bacterial DNA ligases. Microorganisms that synthesize NAD from as few as one to as many as five of the six identified biosynthetic precursors have been identified. De novo NAD synthesis from aspartate or tryptophan is neither universal nor strictly aerobic. Salvage NAD synthesis from nicotinamide, nicotinic acid, nicotinamide riboside, and nicotinic acid riboside occurs via modules of different genes. Nicotinamide salvage genes nadV and pncA, found in distinct bacteria, appear to have spread throughout the tree of life via horizontal gene transfer. Biochemical, genetic, and genomic analyses have advanced to the point at which the precursors and pathways utilized by a microorganism can be predicted. Challenges remain in dissecting regulation of pathways.

  18. Phytozome: a comparative platform for green plant genomics.

    Science.gov (United States)

    Goodstein, David M; Shu, Shengqiang; Howson, Russell; Neupane, Rochak; Hayes, Richard D; Fazo, Joni; Mitros, Therese; Dirks, William; Hellsten, Uffe; Putnam, Nicholas; Rokhsar, Daniel S

    2012-01-01

    The number of sequenced plant genomes and associated genomic resources is growing rapidly with the advent of both an increased focus on plant genomics from funding agencies, and the application of inexpensive next generation sequencing. To interact with this increasing body of data, we have developed Phytozome (http://www.phytozome.net), a comparative hub for plant genome and gene family data and analysis. Phytozome provides a view of the evolutionary history of every plant gene at the level of sequence, gene structure, gene family and genome organization, while at the same time providing access to the sequences and functional annotations of a growing number (currently 25) of complete plant genomes, including all the land plants and selected algae sequenced at the Joint Genome Institute, as well as selected species sequenced elsewhere. Through a comprehensive plant genome database and web portal, these data and analyses are available to the broader plant science research community, providing powerful comparative genomics tools that help to link model systems with other plants of economic and ecological importance.

  19. Analysis of Chinese women with primary ovarian insufficiency by high resolution array-comparative genomic hybridization

    Institute of Scientific and Technical Information of China (English)

    LIAO Can; FU Fang; YANG Xin; SUN Yi-min; LI Dong-zhi

    2011-01-01

    Background Primary ovarian insufficiency (POI) is defined as a primary ovarian defect characterized by absent menarche (primary amenorrhea) or premature depletion of ovarian follicles before the age of 40 years. The etiology of primary ovarian insufficiency in human female patients is still unclear. The purpose of this study is to investigate the potential genetic causes in primary amenorrhea patients by high resolution array based comparative genomic hybridization (array-CGH) analysis.Methods Following the standard karyotyping analysis, genomic DNA from whole blood of 15 primary amenorrhea patients and 15 normal control women was hybridized with Affymetrix cytogenetic 2.7M arrays following the standard protocol. Copy number variations identified by array-CGH were confirmed by real time polymerase chain reaction.Results All the 30 samples were negative by conventional karyotyping analysis. Microdeletions on chromosome 17q21.31-q21.32 with approximately 1.3 Mb were identified in four patients by high resolution array-CGH analysis. This included the female reproductive secretory pathway related factor N-ethylmaleimide-sensitive factor (NSF) gene.Conclusions The results of the present study suggest that there may be critical regions regulating primary ovarian insufficiency in women with a 17q21.31-q21.32 microdeletion. This effect might be due to the loss of function of the NSF gene/genes within the deleted region or to effects on contiguous genes.

  20. Sinbase: an integrated database to study genomics, genetics and comparative genomics in Sesamum indicum.

    Science.gov (United States)

    Wang, Linhai; Yu, Jingyin; Li, Donghua; Zhang, Xiurong

    2015-01-01

    Sesame (Sesamum indicum L.) is an ancient and important oilseed crop grown widely in tropical and subtropical areas. It belongs to the gigantic order Lamiales, which includes many well-known or economically important species, such as olive (Olea europaea), leonurus (Leonurus japonicus) and lavender (Lavandula spica), many of which have important pharmacological properties. Despite their importance, genetic and genomic analyses on these species have been insufficient due to a lack of reference genome information. The now available S. indicum genome will provide an unprecedented opportunity for studying both S. indicum genetic traits and comparative genomics. To deliver S. indicum genomic information to the worldwide research community, we designed Sinbase, a web-based database with comprehensive sesame genomic, genetic and comparative genomic information. Sinbase includes sequences of assembled sesame pseudomolecular chromosomes, protein-coding genes (27,148), transposable elements (372,167) and non-coding RNAs (1,748). In particular, Sinbase provides unique and valuable information on colinear regions with various plant genomes, including Arabidopsis thaliana, Glycine max, Vitis vinifera and Solanum lycopersicum. Sinbase also provides a useful search function and data mining tools, including a keyword search and local BLAST service. Sinbase will be updated regularly with new features, improvements to genome annotation and new genomic sequences, and is freely accessible at http://ocri-genomics.org/Sinbase/.

  1. Dyneins across eukaryotes: a comparative genomic analysis.

    Science.gov (United States)

    Wickstead, Bill; Gull, Keith

    2007-12-01

    Dyneins are large minus-end-directed microtubule motors. Each dynein contains at least one dynein heavy chain (DHC) and a variable number of intermediate chains (IC), light intermediate chains (LIC) and light chains (LC). Here, we used genome sequence data from 24 diverse eukaryotes to assess the distribution of DHCs, ICs, LICs and LCs across Eukaryota. Phylogenetic inference identified nine DHC families (two cytoplasmic and seven axonemal) and six IC families (one cytoplasmic). We confirm that dyneins have been lost from higher plants and show that this is most likely because of a single loss of cytoplasmic dynein 1 from the ancestor of Rhodophyta and Viridiplantae, followed by lineage-specific losses of other families. Independent losses in Entamoeba mean that at least three extant eukaryotic lineages are entirely devoid of dyneins. Cytoplasmic dynein 2 is associated with intraflagellar transport (IFT), but in two chromalveolate organisms, we find an IFT footprint without the retrograde motor. The distribution of one family of outer-arm dyneins accounts for 2-headed or 3-headed outer-arm ultrastructures observed in different organisms. One diatom species builds motile axonemes without any inner-arm dyneins (IAD), and the unexpected conservation of IAD I1 in non-flagellate algae and LC8 (DYNLL1/2) in all lineages reveals a surprising fluidity to dynein function.

  2. Comparative genomics reveals mobile pathogenicity chromosomes in Fusarium

    NARCIS (Netherlands)

    Ma, L.-J.; van der Does, H.C.; Borkovich, K.A.; Coleman, J.J.; Daboussi, M.J.; Di Pietro, A.; Dufresne, M.; Freitag, M.; Grabherr, M.; Henrissat, B.; Houterman, P.M.; Kang, S.; Shim, W.B.; Woloshuk, C.; Xie, X.; Xu, J.-R; Antoniw, J.; Baker, S.E.; Bluhm, B.H.; Breakspear, A.; Brown, D.W.; Butchko, R.A.E.; Chapman, S.; Coulson, R.; Coutinho, P.M.; Danchin, E.G.J.; Diener, A.; Gale, L.R.; Gardiner, D.M.; Goff, S.; Hammond-Kosack, K.E.; Hilburn, K.; Hua-Van, A.; Jonkers, W.; Kazan, K.; Kodira, C.D.; Koehrsen, M.; Kumar, L.; Lee, Y.H.; Li, L.; Manners, J.M.; Miranda-Saavedra, D.; Mukherjee, M.; Park, G.; Park, J.; Park, S.Y.; Proctor, R.H.; Regev, A.; Ruiz-Roldan, M.C.; Sain, D.; Sakthikumar, S.; Sykes, S.; Schwartz, D.C.; Gillian Turgeon, B.; Wapinski, I.; Yoder, O.; Young, S.; Zeng, Q.; Zhou, S.; Galagan, J.; Cuomo, C.A.; Kistler, H.C.; Rep, M.

    2010-01-01

    Fusarium species are among the most important phytopathogenic and toxigenic fungi. To understand the molecular underpinnings of pathogenicity in the genus Fusarium, we compared the genomes of three phenotypically diverse species: Fusarium graminearum, Fusarium verticillioides and Fusarium oxysporum

  3. The perennial ryegrass GenomeZipper: targeted use of genome resources for comparative grass genomics.

    Science.gov (United States)

    Pfeifer, Matthias; Martis, Mihaela; Asp, Torben; Mayer, Klaus F X; Lübberstedt, Thomas; Byrne, Stephen; Frei, Ursula; Studer, Bruno

    2013-02-01

    Whole-genome sequences established for model and major crop species constitute a key resource for advanced genomic research. For outbreeding forage and turf grass species like ryegrasses (Lolium spp.), such resources have yet to be developed. Here, we present a model of the perennial ryegrass (Lolium perenne) genome on the basis of conserved synteny to barley (Hordeum vulgare) and the model grass genome Brachypodium (Brachypodium distachyon) as well as rice (Oryza sativa) and sorghum (Sorghum bicolor). A transcriptome-based genetic linkage map of perennial ryegrass served as a scaffold to establish the chromosomal arrangement of syntenic genes from model grass species. This scaffold revealed a high degree of synteny and macrocollinearity and was then utilized to anchor a collection of perennial ryegrass genes in silico to their predicted genome positions. This resulted in the unambiguous assignment of 3,315 out of 8,876 previously unmapped genes to the respective chromosomes. In total, the GenomeZipper incorporates 4,035 conserved grass gene loci, which were used for the first genome-wide sequence divergence analysis between perennial ryegrass, barley, Brachypodium, rice, and sorghum. The perennial ryegrass GenomeZipper is an ordered, information-rich genome scaffold, facilitating map-based cloning and genome assembly in perennial ryegrass and closely related Poaceae species. It also represents a milestone in describing synteny between perennial ryegrass and fully sequenced model grass genomes, thereby increasing our understanding of genome organization and evolution in the most important temperate forage and turf grass species.

  4. IMGD: an integrated platform supporting comparative genomics and phylogenetics of insect mitochondrial genomes

    Directory of Open Access Journals (Sweden)

    Jung Kyongyong

    2009-04-01

    Full Text Available Abstract Background Sequences and organization of the mitochondrial genome have been used as markers to investigate evolutionary history and relationships in many taxonomic groups. The rapidly increasing mitochondrial genome sequences from diverse insects provide ample opportunities to explore various global evolutionary questions in the superclass Hexapoda. To adequately support such questions, it is imperative to establish an informatics platform that facilitates the retrieval and utilization of available mitochondrial genome sequence data. Results The Insect Mitochondrial Genome Database (IMGD is a new integrated platform that archives the mitochondrial genome sequences from 25,747 hexapod species, including 112 completely sequenced and 20 nearly completed genomes and 113,985 partially sequenced mitochondrial genomes. The Species-driven User Interface (SUI of IMGD supports data retrieval and diverse analyses at multi-taxon levels. The Phyloviewer implemented in IMGD provides three methods for drawing phylogenetic trees and displays the resulting trees on the web. The SNP database incorporated to IMGD presents the distribution of SNPs and INDELs in the mitochondrial genomes of multiple isolates within eight species. A newly developed comparative SNU Genome Browser supports the graphical presentation and interactive interface for the identified SNPs/INDELs. Conclusion The IMGD provides a solid foundation for the comparative mitochondrial genomics and phylogenetics of insects. All data and functions described here are available at the web site http://www.imgd.org/.

  5. Comparative genomic paleontology across plant kingdom reveals the dynamics of TE-driven genome evolution.

    Science.gov (United States)

    El Baidouri, Moaine; Panaud, Olivier

    2013-01-01

    Long terminal repeat-retrotransposons (LTR-RTs) are the most abundant class of transposable elements (TEs) in plants. They strongly impact the structure, function, and evolution of their host genome, and, in particular, their role in genome size variation has been clearly established. However, the dynamics of the process through which LTR-RTs have differentially shaped plant genomes is still poorly understood because of a lack of comparative studies. Using a new robust and automated family classification procedure, we exhaustively characterized the LTR-RTs in eight plant genomes for which a high-quality sequence is available (i.e., Arabidopsis thaliana, A. lyrata, grapevine, soybean, rice, Brachypodium dystachion, sorghum, and maize). This allowed us to perform a comparative genome-wide study of the retrotranspositional landscape in these eight plant lineages from both monocots and dicots. We show that retrotransposition has recurrently occurred in all plant genomes investigated, regardless their size, and through bursts, rather than a continuous process. Moreover, in each genome, only one or few LTR-RT families have been active in the recent past, and the difference in genome size among the species studied could thus mostly be accounted for by the extent of the latest transpositional burst(s). Following these bursts, LTR-RTs are efficiently eliminated from their host genomes through recombination and deletion, but we show that the removal rate is not lineage specific. These new findings lead us to propose a new model of TE-driven genome evolution in plants.

  6. Mycobacterial species as case-study of comparative genome analysis.

    Science.gov (United States)

    Zakham, F; Belayachi, L; Ussery, D; Akrim, M; Benjouad, A; El Aouad, R; Ennaji, M M

    2011-02-08

    The genus Mycobacterium represents more than 120 species including important pathogens of human and cause major public health problems and illnesses. Further, with more than 100 genome sequences from this genus, comparative genome analysis can provide new insights for better understanding the evolutionary events of these species and improving drugs, vaccines, and diagnostics tools for controlling Mycobacterial diseases. In this present study we aim to outline a comparative genome analysis of fourteen Mycobacterial genomes: M. avium subsp. paratuberculosis K—10, M. bovis AF2122/97, M. bovis BCG str. Pasteur 1173P2, M. leprae Br4923, M. marinum M, M. sp. KMS, M. sp. MCS, M. tuberculosis CDC1551, M. tuberculosis F11, M. tuberculosis H37Ra, M. tuberculosis H37Rv, M. tuberculosis KZN 1435 , M. ulcerans Agy99,and M. vanbaalenii PYR—1, For this purpose a comparison has been done based on their length of genomes, GC content, number of genes in different data bases (Genbank, Refseq, and Prodigal). The BLAST matrix of these genomes has been figured to give a lot of information about the similarity between species in a simple scheme. As a result of multiple genome analysis, the pan and core genome have been defined for twelve Mycobacterial species. We have also introduced the genome atlas of the reference strain M. tuberculosis H37Rv which can give a good overview of this genome. And for examining the phylogenetic relationships among these bacteria, a phylogenic tree has been constructed from 16S rRNA gene for tuberculosis and non tuberculosis Mycobacteria to understand the evolutionary events of these species.

  7. DNA Microarrays in Comparative Genomics and Transcriptomics

    DEFF Research Database (Denmark)

    Willenbrock, Hanni

    2007-01-01

    During the past few years, innovations in the DNA sequencing technology has led to an explosion in available DNA sequence information. This has revolutionized biological research and promoted the development of high throughput analysis methods that can take advantage of the vast amount of sequence...... at identifying the exact breakpoints where DNA has been gained or lost. In this thesis, three popular methods are compared and a realistic simulation model is presented for generating artificial data with known breakpoints and known DNA copy number. By using simulated data, we obtain a realistic evaluation...

  8. Comparative rates of evolution in endosymbiotic nuclear genomes

    Directory of Open Access Journals (Sweden)

    Keeling Patrick J

    2006-06-01

    Full Text Available Abstract Background The nucleomorphs associated with secondary plastids of cryptomonads and chlorarachniophytes are the sole examples of organelles with eukaryotic nuclear genomes. Although not as widespread as their prokaryotic equivalents in mitochondria and plastids, nucleomorph genomes share similarities in terms of reduction and compaction. They also differ in several aspects, not least in that they encode proteins that target to the plastid, and so function in a different compartment from that in which they are encoded. Results Here, we test whether the phylogenetically distinct nucleomorph genomes of the cryptomonad, Guillardia theta, and the chlorarachniophyte, Bigelowiella natans, have experienced similar evolutionary pressures during their transformation to reduced organelles. We compared the evolutionary rates of genes from nuclear, nucleomorph, and plastid genomes, all of which encode proteins that function in the same cellular compartment, the plastid, and are thus subject to similar selection pressures. Furthermore, we investigated the divergence of nucleomorphs within cryptomonads by comparing G. theta and Rhodomonas salina. Conclusion Chlorarachniophyte nucleomorph genes have accumulated errors at a faster rate than other genomes within the same cell, regardless of the compartment where the gene product functions. In contrast, most nucleomorph genes in cryptomonads have evolved faster than genes in other genomes on average, but genes for plastid-targeted proteins are not overly divergent, and it appears that cryptomonad nucleomorphs are not presently evolving rapidly and have therefore stabilized. Overall, these analyses suggest that the forces at work in the two lineages are different, despite the similarities between the structures of their genomes.

  9. Comparative Genomics of a Parthenogenesis-Inducing Wolbachia Symbiont

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    Amelia R. I. Lindsey

    2016-07-01

    Full Text Available Wolbachia is an intracellular symbiont of invertebrates responsible for inducing a wide variety of phenotypes in its host. These host-Wolbachia relationships span the continuum from reproductive parasitism to obligate mutualism, and provide a unique system to study genomic changes associated with the evolution of symbiosis. We present the genome sequence from a parthenogenesis-inducing Wolbachia strain (wTpre infecting the minute parasitoid wasp Trichogramma pretiosum. The wTpre genome is the most complete parthenogenesis-inducing Wolbachia genome available to date. We used comparative genomics across 16 Wolbachia strains, representing five supergroups, to identify a core Wolbachia genome of 496 sets of orthologous genes. Only 14 of these sets are unique to Wolbachia when compared to other bacteria from the Rickettsiales. We show that the B supergroup of Wolbachia, of which wTpre is a member, contains a significantly higher number of ankyrin repeat-containing genes than other supergroups. In the wTpre genome, there is evidence for truncation of the protein coding sequences in 20% of ORFs, mostly as a result of frameshift mutations. The wTpre strain represents a conversion from cytoplasmic incompatibility to a parthenogenesis-inducing lifestyle, and is required for reproduction in the Trichogramma host it infects. We hypothesize that the large number of coding frame truncations has accompanied the change in reproductive mode of the wTpre strain.

  10. SNUGB: a versatile genome browser supporting comparative and functional fungal genomics

    Directory of Open Access Journals (Sweden)

    Kim Seungill

    2008-12-01

    Full Text Available Abstract Background Since the full genome sequences of Saccharomyces cerevisiae were released in 1996, genome sequences of over 90 fungal species have become publicly available. The heterogeneous formats of genome sequences archived in different sequencing centers hampered the integration of the data for efficient and comprehensive comparative analyses. The Comparative Fungal Genomics Platform (CFGP was developed to archive these data via a single standardized format that can support multifaceted and integrated analyses of the data. To facilitate efficient data visualization and utilization within and across species based on the architecture of CFGP and associated databases, a new genome browser was needed. Results The Seoul National University Genome Browser (SNUGB integrates various types of genomic information derived from 98 fungal/oomycete (137 datasets and 34 plant and animal (38 datasets species, graphically presents germane features and properties of each genome, and supports comparison between genomes. The SNUGB provides three different forms of the data presentation interface, including diagram, table, and text, and six different display options to support visualization and utilization of the stored information. Information for individual species can be quickly accessed via a new tool named the taxonomy browser. In addition, SNUGB offers four useful data annotation/analysis functions, including 'BLAST annotation.' The modular design of SNUGB makes its adoption to support other comparative genomic platforms easy and facilitates continuous expansion. Conclusion The SNUGB serves as a powerful platform supporting comparative and functional genomics within the fungal kingdom and also across other kingdoms. All data and functions are available at the web site http://genomebrowser.snu.ac.kr/.

  11. Comparative genomic analysis of eutherian interferon-γ-inducible GTPases.

    Science.gov (United States)

    Premzl, Marko

    2012-11-01

    The interferon-γ-inducible GTPases, IFGGs, are intracellular proteins involved in immune response against pathogens. A comprehensive comparative genomic review and analysis of eutherian IFGGs was carried out using public genomic sequences. The 64 eutherian IFGG genes were examined in detail and annotated. The eutherian IFGG promoter types were first catalogued followed by a phylogenetic analysis of eutherian IFGGs, which described five major IFGG clusters. The patterns of differential gene expansions and protein regions that may regulate IFGG catalytic features suggested a new classification of eutherian IFGGs. This mini-review has also provided new tests of reliability of public genomic sequences as well as tests of protein molecular evolution.

  12. Arabidopsis transcription factors: genome-wide comparative analysis among eukaryotes.

    Science.gov (United States)

    Riechmann, J L; Heard, J; Martin, G; Reuber, L; Jiang, C; Keddie, J; Adam, L; Pineda, O; Ratcliffe, O J; Samaha, R R; Creelman, R; Pilgrim, M; Broun, P; Zhang, J Z; Ghandehari, D; Sherman, B K; Yu, G

    2000-12-15

    The completion of the Arabidopsis thaliana genome sequence allows a comparative analysis of transcriptional regulators across the three eukaryotic kingdoms. Arabidopsis dedicates over 5% of its genome to code for more than 1500 transcription factors, about 45% of which are from families specific to plants. Arabidopsis transcription factors that belong to families common to all eukaryotes do not share significant similarity with those of the other kingdoms beyond the conserved DNA binding domains, many of which have been arranged in combinations specific to each lineage. The genome-wide comparison reveals the evolutionary generation of diversity in the regulation of transcription.

  13. Sputnik: a database platform for comparative plant genomics.

    Science.gov (United States)

    Rudd, Stephen; Mewes, Hans-Werner; Mayer, Klaus F X

    2003-01-01

    Two million plant ESTs, from 20 different plant species, and totalling more than one 1000 Mbp of DNA sequence, represents a formidable transcriptomic resource. Sputnik uses the potential of this sequence resource to fill some of the information gap in the un-sequenced plant genomes and to serve as the foundation for in silicio comparative plant genomics. The complexity of the individual EST collections has been reduced using optimised EST clustering techniques. Annotation of cluster sequences is performed by exploiting and transferring information from the comprehensive knowledgebase already produced for the completed model plant genome (Arabidopsis thaliana) and by performing additional state of-the-art sequence analyses relevant to today's plant biologist. Functional predictions, comparative analyses and associative annotations for 500 000 plant EST derived peptides make Sputnik (http://mips.gsf.de/proj/sputnik/) a valid platform for contemporary plant genomics.

  14. Comparative Genomics via Wavelet Analysis for Closely Related Bacteria

    Directory of Open Access Journals (Sweden)

    Jiuzhou Song

    2004-01-01

    Full Text Available Comparative genomics has been a valuable method for extracting and extrapolating genome information among closely related bacteria. The efficiency of the traditional methods is extremely influenced by the software method used. To overcome the problem here, we propose using wavelet analysis to perform comparative genomics. First, global comparison using wavelet analysis gives the difference at a quantitative level. Then local comparison using keto-excess or purine-excess plots shows precise positions of inversions, translocations, and horizontally transferred DNA fragments. We firstly found that the level of energy spectra difference is related to the similarity of bacteria strains; it could be a quantitative index to describe the similarities of genomes. The strategy is described in detail by comparisons of closely related strains: S.typhi CT18, S.typhi Ty2, S.typhimurium LT2, H.pylori 26695, and H.pylori J99.

  15. Comparative Genomics via Wavelet Analysis for Closely Related Bacteria

    Science.gov (United States)

    Song, Jiuzhou; Ware, Tony; Liu, Shu-Lin; Surette, M.

    2004-12-01

    Comparative genomics has been a valuable method for extracting and extrapolating genome information among closely related bacteria. The efficiency of the traditional methods is extremely influenced by the software method used. To overcome the problem here, we propose using wavelet analysis to perform comparative genomics. First, global comparison using wavelet analysis gives the difference at a quantitative level. Then local comparison using keto-excess or purine-excess plots shows precise positions of inversions, translocations, and horizontally transferred DNA fragments. We firstly found that the level of energy spectra difference is related to the similarity of bacteria strains; it could be a quantitative index to describe the similarities of genomes. The strategy is described in detail by comparisons of closely related strains: S.typhi CT18, S.typhi Ty2, S.typhimurium LT2, H.pylori 26695, and H.pylori J99.

  16. Comparative Genome Analysis of Basidiomycete Fungi

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Robert; Salamov, Asaf; Morin, Emmanuelle; Nagy, Laszlo; Manning, Gerard; Baker, Scott; Brown, Daren; Henrissat, Bernard; Levasseur, Anthony; Hibbett, David; Martin, Francis; Grigoriev, Igor

    2012-03-19

    Fungi of the phylum Basidiomycota (basidiomycetes), make up some 37percent of the described fungi, and are important in forestry, agriculture, medicine, and bioenergy. This diverse phylum includes the mushrooms, wood rots, symbionts, and plant and animal pathogens. To better understand the diversity of phenotypes in basidiomycetes, we performed a comparative analysis of 35 basidiomycete fungi spanning the diversity of the phylum. Phylogenetic patterns of lignocellulose degrading genes suggest a continuum rather than a sharp dichotomy between the white rot and brown rot modes of wood decay. Patterns of secondary metabolic enzymes give additional insight into the broad array of phenotypes found in the basidiomycetes. We suggest that the profile of an organism in lignocellulose-targeting genes can be used to predict its nutritional mode, and predict Dacryopinax sp. as a brown rot; Botryobasidium botryosum and Jaapia argillacea as white rots.

  17. Update on comparative genome mapping between Malus and Pyrus

    OpenAIRE

    Nishitani Chikako; Terakami Shingo; Tustin Stuart D; Chagné David; Celton Jean-Marc; Yamamoto Toshiya; Gardiner Susan E

    2009-01-01

    Abstract Background Comparative genome mapping determines the linkage between homologous genes of related taxa. It has already been used in plants to characterize agronomically important genes in lesser studied species, using information from better studied species. In the Maloideae sub-family, which includes fruit species such as apple, pear, loquat and quince, genome co-linearity has been suggested between the genera Malus and Pyrus; however map comparisons are incomplete to date. Findings ...

  18. Genomic and comparative genomic analyses of Rickettsia heilongjiangensis provide insight into its evolution and pathogenesis.

    Science.gov (United States)

    Duan, Changsong; Xiong, Xiaolu; Qi, Yong; Gong, Wenping; Jiao, Jun; Wen, Bohai

    2014-08-01

    Rickettsia heilongjiangensis, the causative agent of far eastern spotted fever, is an obligate intracellular gram-negative bacterium that belongs to the spotted fever group rickettsiae. To understand the evolution and pathogenesis of R. heilongjiangensis, we analyzed its genome and compared it with other rickettsial genomes available in GenBank. The R. heilongjiangensis chromosome contains 1333 genes, including 1297 protein coding genes and 36 RNA coding genes. The genome also contains 121 pseudogenes, 54 insertion sequences, and 39 tandem repeats. Sixteen genes encoding the major components of the type IV secretion systems were identified in the R. heilongjiangensis genome. In total, 37 β-barrel outer membrane proteins were predicted in the genome, eight of which have been previously confirmed to be outer membrane proteins. In addition, 266 potential virulence factor genes, seven partially deleted antibiotic resistance genes, and a genomic island were identified in the genome. The codon usage in the genome is compatible with its low GC content, and the amino acid usage shows apparent bias. A comparative genomic analysis showed that R. heilongjiangensis and R. japonica share one unique fragment that may be a target sequence for a diagnostic assay. The orthologs of 37 genes of R. heilongjiangensis were found in pathogenic R. rickettsii str. Sheila Smith but not in non-pathogenic R. rickettsii str. Iowa, which may explain why R. heilongjiangensis is pathogenic. Pan-genome analysis showed that R. heilongjiangensis and 42 other rickettsiae strains share 693 core genes with a pan-genome size of 4837 genes. The pan-genome-based phylogeny showed that R. heilongjiangensis was closely related to R. japonica.

  19. PSAT: A web tool to compare genomic neighborhoods of multiple prokaryotic genomes

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    Wasnick Michael

    2008-03-01

    Full Text Available Abstract Background The conservation of gene order among prokaryotic genomes can provide valuable insight into gene function, protein interactions, or events by which genomes have evolved. Although some tools are available for visualizing and comparing the order of genes between genomes of study, few support an efficient and organized analysis between large numbers of genomes. The Prokaryotic Sequence homology Analysis Tool (PSAT is a web tool for comparing gene neighborhoods among multiple prokaryotic genomes. Results PSAT utilizes a database that is preloaded with gene annotation, BLAST hit results, and gene-clustering scores designed to help identify regions of conserved gene order. Researchers use the PSAT web interface to find a gene of interest in a reference genome and efficiently retrieve the sequence homologs found in other bacterial genomes. The tool generates a graphic of the genomic neighborhood surrounding the selected gene and the corresponding regions for its homologs in each comparison genome. Homologs in each region are color coded to assist users with analyzing gene order among various genomes. In contrast to common comparative analysis methods that filter sequence homolog data based on alignment score cutoffs, PSAT leverages gene context information for homologs, including those with weak alignment scores, enabling a more sensitive analysis. Features for constraining or ordering results are designed to help researchers browse results from large numbers of comparison genomes in an organized manner. PSAT has been demonstrated to be useful for helping to identify gene orthologs and potential functional gene clusters, and detecting genome modifications that may result in loss of function. Conclusion PSAT allows researchers to investigate the order of genes within local genomic neighborhoods of multiple genomes. A PSAT web server for public use is available for performing analyses on a growing set of reference genomes through any

  20. Comparative Genomic and Phylogenomic Analyses Reveal a Conserved Core Genome Shared by Estuarine and Oceanic Cyanopodoviruses

    Science.gov (United States)

    Huang, Sijun; Zhang, Si; Jiao, Nianzhi; Chen, Feng

    2015-01-01

    Podoviruses are among the major viral groups that infect marine picocyanobacteria Prochlorococcus and Synechococcus. Here, we reported the genome sequences of five Synechococcus podoviruses isolated from the estuarine environment, and performed comparative genomic and phylogenomic analyses based on a total of 20 cyanopodovirus genomes. The genomes of all the known marine cyanopodoviruses are highly syntenic. A pan-genome of 349 clustered orthologous groups was determined, among which 15 were core genes. These core genes make up nearly half of each genome in length, reflecting the high level of genome conservation among this cyanophage type. The whole genome phylogenies based on concatenated core genes and gene content were highly consistent and confirmed the separation of two discrete marine cyanopodovirus clusters MPP-A and MPP-B. The genomes within cluster MPP-B grouped into subclusters mainly corresponding to Prochlorococcus or Synechococcus host types. Auxiliary metabolic genes tend to occur in a specific phylogenetic group of these cyanopodoviruses. All the MPP-B phages analyzed here encode the photosynthesis gene psbA, which are absent in all the MPP-A genomes thus far. Interestingly, all the MPP-B and two MPP-A Synechococcus podoviruses encode the thymidylate synthase gene thyX, while at the same genome locus all the MPP-B Prochlorococcus podoviruses encode the transaldolase gene talC. Both genes are hypothesized to have the potential to facilitate the biosynthesis of deoxynucleotide for phage replication. Inheritance of specific functional genes could be important to the evolution and ecological fitness of certain cyanophage genotypes. Our analyses demonstrate that cyanopodoviruses of estuarine and oceanic origins share a conserved core genome and suggest that accessory genes may be related to environmental adaptation. PMID:26569403

  1. Comparative Genomic and Phylogenomic Analyses Reveal a Conserved Core Genome Shared by Estuarine and Oceanic Cyanopodoviruses.

    Directory of Open Access Journals (Sweden)

    Sijun Huang

    Full Text Available Podoviruses are among the major viral groups that infect marine picocyanobacteria Prochlorococcus and Synechococcus. Here, we reported the genome sequences of five Synechococcus podoviruses isolated from the estuarine environment, and performed comparative genomic and phylogenomic analyses based on a total of 20 cyanopodovirus genomes. The genomes of all the known marine cyanopodoviruses are highly syntenic. A pan-genome of 349 clustered orthologous groups was determined, among which 15 were core genes. These core genes make up nearly half of each genome in length, reflecting the high level of genome conservation among this cyanophage type. The whole genome phylogenies based on concatenated core genes and gene content were highly consistent and confirmed the separation of two discrete marine cyanopodovirus clusters MPP-A and MPP-B. The genomes within cluster MPP-B grouped into subclusters mainly corresponding to Prochlorococcus or Synechococcus host types. Auxiliary metabolic genes tend to occur in a specific phylogenetic group of these cyanopodoviruses. All the MPP-B phages analyzed here encode the photosynthesis gene psbA, which are absent in all the MPP-A genomes thus far. Interestingly, all the MPP-B and two MPP-A Synechococcus podoviruses encode the thymidylate synthase gene thyX, while at the same genome locus all the MPP-B Prochlorococcus podoviruses encode the transaldolase gene talC. Both genes are hypothesized to have the potential to facilitate the biosynthesis of deoxynucleotide for phage replication. Inheritance of specific functional genes could be important to the evolution and ecological fitness of certain cyanophage genotypes. Our analyses demonstrate that cyanopodoviruses of estuarine and oceanic origins share a conserved core genome and suggest that accessory genes may be related to environmental adaptation.

  2. DCODE.ORG Anthology of Comparative Genomic Tools

    Energy Technology Data Exchange (ETDEWEB)

    Loots, G G; Ovcharenko, I

    2005-01-11

    Comparative genomics provides the means to demarcate functional regions in anonymous DNA sequences. The successful application of this method to identifying novel genes is currently shifting to deciphering the noncoding encryption of gene regulation across genomes. To facilitate the use of comparative genomics to practical applications in genetics and genomics we have developed several analytical and visualization tools for the analysis of arbitrary sequences and whole genomes. These tools include two alignment tools: zPicture and Mulan; a phylogenetic shadowing tool: eShadow for identifying lineage- and species-specific functional elements; two evolutionary conserved transcription factor analysis tools: rVista and multiTF; a tool for extracting cis-regulatory modules governing the expression of co-regulated genes, CREME; and a dynamic portal to multiple vertebrate and invertebrate genome alignments, the ECR Browser. Here we briefly describe each one of these tools and provide specific examples on their practical applications. All the tools are publicly available at the http://www.dcode.org/ web site.

  3. Assigning protein functions by comparative genome analysis protein phylogenetic profiles

    Science.gov (United States)

    Pellegrini, Matteo; Marcotte, Edward M.; Thompson, Michael J.; Eisenberg, David; Grothe, Robert; Yeates, Todd O.

    2003-05-13

    A computational method system, and computer program are provided for inferring functional links from genome sequences. One method is based on the observation that some pairs of proteins A' and B' have homologs in another organism fused into a single protein chain AB. A trans-genome comparison of sequences can reveal these AB sequences, which are Rosetta Stone sequences because they decipher an interaction between A' and B. Another method compares the genomic sequence of two or more organisms to create a phylogenetic profile for each protein indicating its presence or absence across all the genomes. The profile provides information regarding functional links between different families of proteins. In yet another method a combination of the above two methods is used to predict functional links.

  4. Comparative genomics of toxigenic and non-toxigenic Staphylococcus hyicus

    DEFF Research Database (Denmark)

    Leekitcharoenphon, Pimlapas; Pamp, Sünje Johanna; Andresen, Lars Ole;

    2016-01-01

    The most common causative agent of exudative epidermitis (EE) in pigs is Staphylococcus hyicus. S. hyicus can be grouped into toxigenic and non-toxigenic strains based on their ability to cause EE in pigs and specific virulence genes have been identified. A genome wide comparison between non......-toxigenic and toxigenic strains has never been performed. In this study, we sequenced eleven toxigenic and six non-toxigenic S. hyicus strains and performed comparative genomic and phylogenetic analysis. Our analyses revealed two genomic regions encoding genes that were predominantly found in toxigenic strains...... (polymorphic toxin) and was associated with the gene encoding ExhA. A clear differentiation between toxigenic and non-toxigenic strains based on genomic and phylogenetic analyses was not apparent. The results of this study support the observation that exfoliative toxins of S. hyicus and S. aureus are located...

  5. Comparative genomics and phylogenetic analysis of S. dysenteriae subgroup

    Institute of Scientific and Technical Information of China (English)

    YANG; E; BIN; Wen; PENG; Junping; ZHANG; Xiaobing; WANG; Ji

    2005-01-01

    Genomic compositions of representatives of thirteen S. Dysenteriae serotypes were investigated by performing comparative genomic hybridization (CGH) with microarray containing the whole genomic ORFs (open reading frames, ORFs) of E. Coli K12 strain MG1655 and specific ORFs of S. Dysenteriae A1 strain Sd51197. The CGH results indicated the genomes of the serotypes contain 2654 conserved ORFs originating from E. Coli. However, 219 intrinsic genes of E. Coli including those prophage genes, molecular chaperones, synthesis of specific O antigen and so on were absent. Moreover, some specific genes such as type II secretion system associated components, iron transport related genes and some others as well were acquired through horizontal transfer. According to phylogenic trees based on genetic composition, it was demonstrated that A1, A2, A8, A10 were distinct from the other S. Dysenteriae serotypes. Our results in this report may provide new insights into the physiological process, pathogenicity and evolution of S. Dysenteriae.

  6. Cytogenetic analysis from DNA by comparative genomic hybridization.

    Science.gov (United States)

    Tachdjian, G; Aboura, A; Lapierre, J M; Viguié, F

    2000-01-01

    Comparative genomic hybridization (CGH) is a modified in situ hybridization technique which allows detection and mapping of DNA sequence copy differences between two genomes in a single experiment. In CGH analysis, two differentially labelled genomic DNA (study and reference) are co-hybridized to normal metaphase spreads. Chromosomal locations of copy number changes in the DNA segments of the study genome are revealed by a variable fluorescence intensity ratio along each target chromosome. Since its development, CGH has been applied mostly as a research tool in the field of cancer cytogenetics to identify genetic changes in many previously unknown regions. CGH may also have a role in clinical cytogenetics for detection and identification of unbalanced chromosomal abnormalities.

  7. Comparative bacterial proteomics: analysis of the core genome concept.

    Directory of Open Access Journals (Sweden)

    Stephen J Callister

    Full Text Available While comparative bacterial genomic studies commonly predict a set of genes indicative of common ancestry, experimental validation of the existence of this core genome requires extensive measurement and is typically not undertaken. Enabled by an extensive proteome database developed over six years, we have experimentally verified the expression of proteins predicted from genomic ortholog comparisons among 17 environmental and pathogenic bacteria. More exclusive relationships were observed among the expressed protein content of phenotypically related bacteria, which is indicative of the specific lifestyles associated with these organisms. Although genomic studies can establish relative orthologous relationships among a set of bacteria and propose a set of ancestral genes, our proteomics study establishes expressed lifestyle differences among conserved genes and proposes a set of expressed ancestral traits.

  8. Comparative Bacterial Proteomics: Analysis of the Core Genome Concept

    Energy Technology Data Exchange (ETDEWEB)

    Callister, Stephen J.; McCue, Lee Ann; Turse, Josh E.; Monroe, Matthew E.; Auberry, Kenneth J.; Smith, Richard D.; Adkins, Joshua N.; Lipton, Mary S.

    2008-02-06

    Comparative bacterial genomic studies commonly predict a set of genes indicative of common ancestry. Experimental validation of the existence of this core genome requires extensive measurement and is not typically undertaken. Enabled by an extensive proteome database development over a six year period, we experimentally verified the expression of proteins predicted from genomic ortholog comparisons among 17 environmental and pathogenic bacteria. More exclusive relationships were observed among the expressed protein content of phenotypically related bacteria, which is indicative of the specific lifestyles associated with these organisms. While genomic studies establish relative orthologous relationships among a set of bacteria and propose a set of ancestral genes, our proteomics study establishes expressed lifestyle differences among conserved genes and proposes a set of expressed ancestral traits.

  9. Comparative genomics and proteomics of 13 Porphyromonas gingivalis strains

    Directory of Open Access Journals (Sweden)

    Tsute Chen

    2015-09-01

    Full Text Available At the current time, genome sequences of a total of 13 Porphyromonas gingivalis strains are available, including five completed genomes (strains ATCC 33277, HG66, TDC60, JCVISC001, and W83 and eight high-coverage draft sequences (F0185, F0566, F0568, F0569, F0570, SJD2, W4087, and W50 that are assembled into fewer than 300 contigs. This study compared these genomes at both nucleotide and protein sequence levels in order to understand their phylogenetic and functional relatedness. There are four copies of 16S rRNA gene sequences in each of the strains of ATCC 33277, HG66, TDC60, and W83 and one copy in the other nine genomes. These 25 16S rRNA sequences represent only 13 unique sequences. The five copies in W83 and W50 are identical and the three copies in HG66 are identical to the four copies in ATCC 33277, suggesting close evolutionary lineage between W83 and W50, as well as HG66 and ATCC 33277. Genome-wide comparison based on “Rapid Annotation using Subsystem Technology” (RAST also showed that for the overall biological functions of the genomes, W83 is closer to W50, and HG66 to ATCC33277, than to other genomes. The comparison of the RAST subsystems identified biological functions that are unique to individual, shared by some, or by all genomes. Functions unique to individual genomes include: a tetracycline resistance protein TetQ, DNA metabolism gene YcfH, and DNA repair gene exonuclease SbcC (only in SJD2; very-short-patch mismatch repair endonuclease and a phage packaging terminase similar to Bacteroides phage B124-14 (in W4087; an internalin similar to a Listeria surface virulence protein (W83; a Type I restriction-modification system (F0569; an iron acquisition/heme transport protein (F0566; colicin I receptor and carbamoylputrescine amidase (W50; L-serine dehydratase (TDC60; and spermidine synthase and ribokinase (JCVISC001. The results also identified biological functions that are missing in individual or several genomes. For

  10. Low-pass sequencing for microbial comparative genomics

    Directory of Open Access Journals (Sweden)

    Kennedy Sean

    2004-01-01

    Full Text Available Abstract Background We studied four extremely halophilic archaea by low-pass shotgun sequencing: (1 the metabolically versatile Haloarcula marismortui; (2 the non-pigmented Natrialba asiatica; (3 the psychrophile Halorubrum lacusprofundi and (4 the Dead Sea isolate Halobaculum gomorrense. Approximately one thousand single pass genomic sequences per genome were obtained. The data were analyzed by comparative genomic analyses using the completed Halobacterium sp. NRC-1 genome as a reference. Low-pass shotgun sequencing is a simple, inexpensive, and rapid approach that can readily be performed on any cultured microbe. Results As expected, the four archaeal halophiles analyzed exhibit both bacterial and eukaryotic characteristics as well as uniquely archaeal traits. All five halophiles exhibit greater than sixty percent GC content and low isoelectric points (pI for their predicted proteins. Multiple insertion sequence (IS elements, often involved in genome rearrangements, were identified in H. lacusprofundi and H. marismortui. The core biological functions that govern cellular and genetic mechanisms of H. sp. NRC-1 appear to be conserved in these four other halophiles. Multiple TATA box binding protein (TBP and transcription factor IIB (TFB homologs were identified from most of the four shotgunned halophiles. The reconstructed molecular tree of all five halophiles shows a large divergence between these species, but with the closest relationship being between H. sp. NRC-1 and H. lacusprofundi. Conclusion Despite the diverse habitats of these species, all five halophiles share (1 high GC content and (2 low protein isoelectric points, which are characteristics associated with environmental exposure to UV radiation and hypersalinity, respectively. Identification of multiple IS elements in the genome of H. lacusprofundi and H. marismortui suggest that genome structure and dynamic genome reorganization might be similar to that previously observed in the

  11. Genetic profiles of gastroesophageal cancer: combined analysis using expression array and tiling array--comparative genomic hybridization

    DEFF Research Database (Denmark)

    Jönsson, Mats; Isinger-Ekstrand, Anna; Johansson, Jan;

    2010-01-01

    /losses and gene expression profiles show strong similarity between cancers in the distal esophagus and the gastroesophageal junction with frequent upregulation of CDK6 and EGFR, whereas gastric cancer displays distinct genetic changes. These data suggest that molecular diagnostics and targeted therapies can......15, 13q34, and 12q13, whereas different profiles with gains at 5p15, 7p22, 2q35, and 13q34 characterized gastric cancers. CDK6 and EGFR were identified as putative target genes in cancers of the esophagus and the gastroesophageal junction, with upregulation in one quarter of the tumors. Gains......-resolution array-based comparative genomic hybridization and 27k oligo gene expression arrays, and putative target genes were validated in an extended series. Adenocarcinomas in the distal esophagus and the gastroesophageal junction showed strong similarities with the most common gains at 20q13, 8q24, 1q21-23, 5p...

  12. On the Approximability of Comparing Genomes with Duplicates

    CERN Document Server

    Angibaud, Sébastien; Rusu, Irena; Thevenin, Annelyse; Vialette, Stéphane

    2008-01-01

    A central problem in comparative genomics consists in computing a (dis-)similarity measure between two genomes, e.g. in order to construct a phylogeny. All the existing measures are defined on genomes without duplicates. However, we know that genes can be duplicated within the same genome. One possible approach to overcome this difficulty is to establish a one-to-one correspondence (i.e. a matching) between genes of both genomes, where the correspondence is chosen in order to optimize the studied measure. In this paper, we are interested in three measures (number of breakpoints, number of common intervals and number of conserved intervals) and three models of matching (exemplar, intermediate and maximum matching models). We prove that, for each model and each measure M, computing a matching between two genomes that optimizes M is APX-hard. We also study the complexity of the following problem: is there an exemplarization (resp. an intermediate/maximum matching) that induces no breakpoint? We prove the problem...

  13. Evolution of cancer suppression as revealed by mammalian comparative genomics.

    Science.gov (United States)

    Tollis, Marc; Schiffman, Joshua D; Boddy, Amy M

    2017-02-02

    Cancer suppression is an important feature in the evolution of large and long-lived animals. While some tumor suppression pathways are conserved among all multicellular organisms, others mechanisms of cancer resistance are uniquely lineage specific. Comparative genomics has become a powerful tool to discover these unique and shared molecular adaptations in respect to cancer suppression. These findings may one day be translated to human patients through evolutionary medicine. Here, we will review theory and methods of comparative cancer genomics and highlight major findings of cancer suppression across mammals. Our current knowledge of cancer genomics suggests that more efficient DNA repair and higher sensitivity to DNA damage may be the key to tumor suppression in large or long-lived mammals.

  14. A translocation t(6;14) in two cases of leiomyosarcoma: Molecular cytogenetic and array-based comparative genomic hybridization characterization.

    Science.gov (United States)

    de Graaff, Marieke A; de Jong, Daniëlle; Briaire-de Bruijn, Inge H; Hogendoorn, Pancras C W; Bovée, Judith V M G; Szuhai, Károly

    2015-11-01

    Leiomyosarcomas are malignant mesenchymal tumors that recapitulate smooth muscle cell differentiation. Tumors are characterized by a genetic heterogeneity with complex karyotypes without a tumor-specific genetic aberration. Their pathobiology is still poorly understood and no specific targeted treatment is currently available for these aggressive tumors. For six leiomyosarcomas, cells were cultured and analyzed by combined binary ratio labeling fluorescence in situ hybridization (COBRA-FISH) karyotyping. A t(6;14) was identified in two cases. FISH breakpoint mapping of case L1339 reveals a breakpoint at chromosome 6p21.31 close to HMGA1, and a small deletion was observed on the distal side of the gene. A small homozygous deletion was also found in the breakpoint region of chromosome 14q24.1 involving ACTN1. The second case revealed a der(6)t(6;14)(p21.1;q21.3), with a duplication adjacent to the breakpoint at chromosome 6. Confirmatory FISH revealed a second leiomyosarcoma with an aberration at 14q24.1. Alterations at this locus were found in 5% (2 of 39) of the leiomyosarcomas in this study. The other identified breakpoints appeared to be non-recurrent, because they were not detected in other leiomyosarcomas, uterine leiomyomas, undifferentiated spindle cell sarcomas, or undifferentiated pleomorphic sarcomas.

  15. Congenital diaphragmatic hernia and chromosome 15q26: determination of a candidate region by use of fluorescent in situ hybridization and array-based comparative genomic hybridization

    NARCIS (Netherlands)

    M. Klaassens (Merel); C. Wouters (Cokkie); M.F. van Dooren (Marieke); H.J.F.M.M. Eussen (Bert); H. Douben (Hannie); J.E.M.M. de Klein (Annelies); A.T. den Dekker (Alexander); C. Lee; P.K. Donahoe; D. Tibboel (Dick); R-J.H. Galjaard (Robert-Jan); N.N.T. Goemaere (Natascha); B.A. Oostra (Ben); R.R. de Krijger (Ronald); J. Wauters (Jan)

    2005-01-01

    textabstractCongenital diaphragmatic hernia (CDH) has an incidence of 1 in 3,000 births and a high mortality rate (33%-58%). Multifactorial inheritance, teratogenic agents, and genetic abnormalities have all been suggested as possible etiologic factors. To define candidate regions

  16. A combined array-based comparative genomic hybridization and functional library screening approach identifies mir-30d as an oncomir in cancer.

    Science.gov (United States)

    Li, Ning; Kaur, Sippy; Greshock, Joel; Lassus, Heini; Zhong, Xiaomin; Wang, Yanling; Leminen, Arto; Shao, Zhongjun; Hu, Xiaowen; Liang, Shun; Katsaros, Dionyssios; Huang, Qihong; Bützow, Ralf; Weber, Barbara L; Coukos, George; Zhang, Lin

    2012-01-01

    Oncomirs are microRNAs (miRNA) that acts as oncogenes or tumor suppressor genes. Efficient identification of oncomirs remains a challenge. Here we report a novel, clinically guided genetic screening approach for the identification of oncomirs, identifying mir-30d through this strategy. mir-30d regulates tumor cell proliferation, apoptosis, senescence, and migration. The chromosomal locus harboring mir-30d was amplified in more than 30% of multiple types of human solid tumors (n = 1,283). Importantly, higher levels of mir-30d expression were associated significantly with poor clinical outcomes in ovarian cancer patients (n = 330, P = 0.0016). Mechanistic investigations suggested that mir-30d regulates a large number of cancer-associated genes, including the apoptotic caspase CASP3. The guided genetic screening approach validated by this study offers a powerful tool to identify oncomirs that may have utility as biomarkers or targets for drug development.

  17. Comparative Genomics of Escherichia coli Strains Causing Urinary Tract Infections

    DEFF Research Database (Denmark)

    Vejborg, Rebecca Munk; Hancock, Viktoria; Schembri, Mark A.

    2011-01-01

    The virulence determinants of uropathogenic Escherichia coli have been studied extensively over the years, but relatively little is known about what differentiates isolates causing various types of urinary tract infections. In this study, we compared the genomic profiles of 45 strains from a range...

  18. Comparative Whole-Genome Mapping To Determine Staphylococcus aureus Genome Size, Virulence Motifs, and Clonality

    Science.gov (United States)

    Pantrang, Madhulatha; Stahl, Buffy; Briska, Adam M.; Stemper, Mary E.; Wagner, Trevor K.; Zentz, Emily B.; Callister, Steven M.; Lovrich, Steven D.; Henkhaus, John K.; Dykes, Colin W.

    2012-01-01

    Despite being a clonal pathogen, Staphylococcus aureus continues to acquire virulence and antibiotic-resistant genes located on mobile genetic elements such as genomic islands, prophages, pathogenicity islands, and the staphylococcal chromosomal cassette mec (SCCmec) by horizontal gene transfer from other staphylococci. The potential virulence of a S. aureus strain is often determined by comparing its pulsed-field gel electrophoresis (PFGE) or multilocus sequence typing profiles to that of known epidemic or virulent clones and by PCR of the toxin genes. Whole-genome mapping (formerly optical mapping), which is a high-resolution ordered restriction mapping of a bacterial genome, is a relatively new genomic tool that allows comparative analysis across entire bacterial genomes to identify regions of genomic similarities and dissimilarities, including small and large insertions and deletions. We explored whether whole-genome maps (WGMs) of methicillin-resistant S. aureus (MRSA) could be used to predict the presence of methicillin resistance, SCCmec type, and Panton-Valentine leukocidin (PVL)-producing genes on an S. aureus genome. We determined the WGMs of 47 diverse clinical isolates of S. aureus, including well-characterized reference MRSA strains, and annotated the signature restriction pattern in SCCmec types, arginine catabolic mobile element (ACME), and PVL-carrying prophage, PhiSa2 or PhiSa2-like regions on the genome. WGMs of these isolates accurately characterized them as MRSA or methicillin-sensitive S. aureus based on the presence or absence of the SCCmec motif, ACME and the unique signature pattern for the prophage insertion that harbored the PVL genes. Susceptibility to methicillin resistance and the presence of mecA, SCCmec types, and PVL genes were confirmed by PCR. A WGM clustering approach was further able to discriminate isolates within the same PFGE clonal group. These results showed that WGMs could be used not only to genotype S. aureus but also to

  19. Restauro-G: A Rapid Genome Re-Annotation System for Comparative Genomics

    Institute of Scientific and Technical Information of China (English)

    Satoshi Tamaki; Kazuharu Arakawa; Nobuaki Kono; Masaru Tomita

    2007-01-01

    Annotations of complete genome sequences submitted directly from sequencing projects are diverse in terms of annotation strategies and update frequencies. These inconsistencies make comparative studies difficult. To allow rapid data preparation of a large number of complete genomes, automation and speed are important for genome re-annotation. Here we introduce an open-source rapid genome re-annotation software system, Restauro-G, specialized for bacterial genomes. Restauro-G re-annotates a genome by similarity searches utilizing the BLAST-Like Alignment Tool, referring to protein databases such as UniProt KB, NCBI nr, NCBI COGs, Pfam, and PSORTb. Re-annotation by Restauro-G achieved over 98% accuracy for most bacterial chromosomes in comparison with the original manually curated annotation of EMBL releases. Restauro-G was developed in the generic bioinformatics workbench G-language Genome Analysis Environment and is distributed at http://restauro-g.iab.keio.ac.jp/ under the GNU General Public License.

  20. A web server for mining Comparative Genomic Hybridization (CGH) data

    Science.gov (United States)

    Liu, Jun; Ranka, Sanjay; Kahveci, Tamer

    2007-11-01

    Advances in cytogenetics and molecular biology has established that chromosomal alterations are critical in the pathogenesis of human cancer. Recurrent chromosomal alterations provide cytological and molecular markers for the diagnosis and prognosis of disease. They also facilitate the identification of genes that are important in carcinogenesis, which in the future may help in the development of targeted therapy. A large amount of publicly available cancer genetic data is now available and it is growing. There is a need for public domain tools that allow users to analyze their data and visualize the results. This chapter describes a web based software tool that will allow researchers to analyze and visualize Comparative Genomic Hybridization (CGH) datasets. It employs novel data mining methodologies for clustering and classification of CGH datasets as well as algorithms for identifying important markers (small set of genomic intervals with aberrations) that are potentially cancer signatures. The developed software will help in understanding the relationships between genomic aberrations and cancer types.

  1. CyanoClust: comparative genome resources of cyanobacteria and plastids.

    Science.gov (United States)

    Sasaki, Naobumi V; Sato, Naoki

    2010-01-01

    Cyanobacteria, which perform oxygen-evolving photosynthesis as do chloroplasts of plants and algae, are one of the best-studied prokaryotic phyla and one from which many representative genomes have been sequenced. Lack of a suitable comparative genomic database has been a problem in cyanobacterial genomics because many proteins involved in physiological functions such as photosynthesis and nitrogen fixation are not catalogued in commonly used databases, such as Clusters of Orthologous Proteins (COG). CyanoClust is a database of homolog groups in cyanobacteria and plastids that are produced by the program Gclust. We have developed a web-server system for the protein homology database featuring cyanobacteria and plastids. Database URL: http://cyanoclust.c.u-tokyo.ac.jp/.

  2. Phylogeny and comparative genome analysis of a Basidiomycete fungi

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Robert W.; Salamov, Asaf; Grigoriev, Igor; Hibbett, David

    2011-03-14

    Fungi of the phylum Basidiomycota, make up some 37percent of the described fungi, and are important from the perspectives of forestry, agriculture, medicine, and bioenergy. This diverse phylum includes the mushrooms, wood rots, plant pathogenic rusts and smuts, and some human pathogens. To better understand these important fungi, we have undertaken a comparative genomic analysis of the Basidiomycetes with available sequenced genomes. We report a phylogeny that sheds light on previously unclear evolutionary relationships among the Basidiomycetes. We also define a `core proteome? based on protein families conserved in all Basidiomycetes. We identify key expansions and contractions in protein families that may be responsible for the degradation of plant biomass such as cellulose, hemicellulose, and lignin. Finally, we speculate as to the genomic changes that drove such expansions and contractions.

  3. Lactobacillus paracasei comparative genomics: towards species pan-genome definition and exploitation of diversity.

    Directory of Open Access Journals (Sweden)

    Tamara Smokvina

    Full Text Available Lactobacillus paracasei is a member of the normal human and animal gut microbiota and is used extensively in the food industry in starter cultures for dairy products or as probiotics. With the development of low-cost, high-throughput sequencing techniques it has become feasible to sequence many different strains of one species and to determine its "pan-genome". We have sequenced the genomes of 34 different L. paracasei strains, and performed a comparative genomics analysis. We analysed genome synteny and content, focussing on the pan-genome, core genome and variable genome. Each genome was shown to contain around 2800-3100 protein-coding genes, and comparative analysis identified over 4200 ortholog groups that comprise the pan-genome of this species, of which about 1800 ortholog groups make up the conserved core. Several factors previously associated with host-microbe interactions such as pili, cell-envelope proteinase, hydrolases p40 and p75 or the capacity to produce short branched-chain fatty acids (bkd operon are part of the L. paracasei core genome present in all analysed strains. The variome consists mainly of hypothetical proteins, phages, plasmids, transposon/conjugative elements, and known functions such as sugar metabolism, cell-surface proteins, transporters, CRISPR-associated proteins, and EPS biosynthesis proteins. An enormous variety and variability of sugar utilization gene cassettes were identified, with each strain harbouring between 25-53 cassettes, reflecting the high adaptability of L. paracasei to different niches. A phylogenomic tree was constructed based on total genome contents, and together with an analysis of horizontal gene transfer events we conclude that evolution of these L. paracasei strains is complex and not always related to niche adaptation. The results of this genome content comparison was used, together with high-throughput growth experiments on various carbohydrates, to perform gene-trait matching analysis

  4. The Chlamydia psittaci genome: a comparative analysis of intracellular pathogens.

    Directory of Open Access Journals (Sweden)

    Anja Voigt

    Full Text Available BACKGROUND: Chlamydiaceae are a family of obligate intracellular pathogens causing a wide range of diseases in animals and humans, and facing unique evolutionary constraints not encountered by free-living prokaryotes. To investigate genomic aspects of infection, virulence and host preference we have sequenced Chlamydia psittaci, the pathogenic agent of ornithosis. RESULTS: A comparison of the genome of the avian Chlamydia psittaci isolate 6BC with the genomes of other chlamydial species, C. trachomatis, C. muridarum, C. pneumoniae, C. abortus, C. felis and C. caviae, revealed a high level of sequence conservation and synteny across taxa, with the major exception of the human pathogen C. trachomatis. Important differences manifest in the polymorphic membrane protein family specific for the Chlamydiae and in the highly variable chlamydial plasticity zone. We identified a number of psittaci-specific polymorphic membrane proteins of the G family that may be related to differences in host-range and/or virulence as compared to closely related Chlamydiaceae. We calculated non-synonymous to synonymous substitution rate ratios for pairs of orthologous genes to identify putative targets of adaptive evolution and predicted type III secreted effector proteins. CONCLUSIONS: This study is the first detailed analysis of the Chlamydia psittaci genome sequence. It provides insights in the genome architecture of C. psittaci and proposes a number of novel candidate genes mostly of yet unknown function that may be important for pathogen-host interactions.

  5. Comparative genomics of Neisseria meningitidis: core genome, islands of horizontal transfer and pathogen-specific genes.

    Science.gov (United States)

    Dunning Hotopp, Julie C; Grifantini, Renata; Kumar, Nikhil; Tzeng, Yih Ling; Fouts, Derrick; Frigimelica, Elisabetta; Draghi, Monia; Giuliani, Marzia Monica; Rappuoli, Rino; Stephens, David S; Grandi, Guido; Tettelin, Hervé

    2006-12-01

    To better understand Neisseria meningitidis genomes and virulence, microarray comparative genome hybridization (mCGH) data were collected from one Neisseria cinerea, two Neisseria lactamica, two Neisseria gonorrhoeae and 48 Neisseria meningitidis isolates. For N. meningitidis, these isolates are from diverse clonal complexes, invasive and carriage strains, and all major serogroups. The microarray platform represented N. meningitidis strains MC58, Z2491 and FAM18, and N. gonorrhoeae FA1090. By comparing hybridization data to genome sequences, the core N. meningitidis genome and insertions/deletions (e.g. capsule locus, type I secretion system) related to pathogenicity were identified, including further characterization of the capsule locus, bioinformatics analysis of a type I secretion system, and identification of some metabolic pathways associated with intracellular survival in pathogens. Hybridization data clustered meningococcal isolates from similar clonal complexes that were distinguished by the differential presence of six distinct islands of horizontal transfer. Several of these islands contained prophage or other mobile elements, including a novel prophage and a transposon carrying portions of a type I secretion system. Acquisition of some genetic islands appears to have occurred in multiple lineages, including transfer between N. lactamica and N. meningitidis. However, island acquisition occurs infrequently, such that the genomic-level relationship is not obscured within clonal complexes. The N. meningitidis genome is characterized by the horizontal acquisition of multiple genetic islands; the study of these islands reveals important sets of genes varying between isolates and likely to be related to pathogenicity.

  6. Whole genome comparative studies between chicken and turkey and their implications for avian genome evolution

    Directory of Open Access Journals (Sweden)

    Carré Wilfrid

    2008-04-01

    Full Text Available Abstract Background Comparative genomics is a powerful means of establishing inter-specific relationships between gene function/location and allows insight into genomic rearrangements, conservation and evolutionary phylogeny. The availability of the complete sequence of the chicken genome has initiated the development of detailed genomic information in other birds including turkey, an agriculturally important species where mapping has hitherto focused on linkage with limited physical information. No molecular study has yet examined conservation of avian microchromosomes, nor differences in copy number variants (CNVs between birds. Results We present a detailed comparative cytogenetic map between chicken and turkey based on reciprocal chromosome painting and mapping of 338 chicken BACs to turkey metaphases. Two inter-chromosomal changes (both involving centromeres and three pericentric inversions have been identified between chicken and turkey; and array CGH identified 16 inter-specific CNVs. Conclusion This is the first study to combine the modalities of zoo-FISH and array CGH between different avian species. The first insight into the conservation of microchromosomes, the first comparative cytogenetic map of any bird and the first appraisal of CNVs between birds is provided. Results suggest that avian genomes have remained relatively stable during evolution compared to mammalian equivalents.

  7. The Perennial Ryegrass GenomeZipper – Targeted Use of Genome Resources for Comparative Grass Genomics

    DEFF Research Database (Denmark)

    Pfeiffer, Matthias; Martis, Mihaela; Asp, Torben;

    2013-01-01

    to establish the chromosomal arrangement of syntenic genes from model grass species. This scaffold revealed a high degree of synteny and macrocollinearity and was then utilized to anchor a collection of perennial ryegrass genes in silico to their predicted genome positions. This resulted in the unambiguous...

  8. Sequencing and comparative genome analysis of two pathogenic Streptococcus gallolyticus subspecies: genome plasticity, adaptation and virulence.

    Directory of Open Access Journals (Sweden)

    I-Hsuan Lin

    Full Text Available Streptococcus gallolyticus infections in humans are often associated with bacteremia, infective endocarditis and colon cancers. The disease manifestations are different depending on the subspecies of S. gallolyticus causing the infection. Here, we present the complete genomes of S. gallolyticus ATCC 43143 (biotype I and S. pasteurianus ATCC 43144 (biotype II.2. The genomic differences between the two biotypes were characterized with comparative genomic analyses. The chromosome of ATCC 43143 and ATCC 43144 are 2,36 and 2,10 Mb in length and encode 2246 and 1869 CDS respectively. The organization and genomic contents of both genomes were most similar to the recently published S. gallolyticus UCN34, where 2073 (92% and 1607 (86% of the ATCC 43143 and ATCC 43144 CDS were conserved in UCN34 respectively. There are around 600 CDS conserved in all Streptococcus genomes, indicating the Streptococcus genus has a small core-genome (constitute around 30% of total CDS and substantial evolutionary plasticity. We identified eight and five regions of genome plasticity in ATCC 43143 and ATCC 43144 respectively. Within these regions, several proteins were recognized to contribute to the fitness and virulence of each of the two subspecies. We have also predicted putative cell-surface associated proteins that could play a role in adherence to host tissues, leading to persistent infections causing sub-acute and chronic diseases in humans. This study showed evidence that the S. gallolyticus still possesses genes making it suitable in a rumen environment, whereas the ability for S. pasteurianus to live in rumen is reduced. The genome heterogeneity and genetic diversity among the two biotypes, especially membrane and lipoproteins, most likely contribute to the differences in the pathogenesis of the two S. gallolyticus biotypes and the type of disease an infected patient eventually develops.

  9. Comparative genomics reveals diversity among xanthomonads infecting tomato and pepper

    Directory of Open Access Journals (Sweden)

    Koebnik Ralf

    2011-03-01

    Full Text Available Abstract Background Bacterial spot of tomato and pepper is caused by four Xanthomonas species and is a major plant disease in warm humid climates. The four species are distinct from each other based on physiological and molecular characteristics. The genome sequence of strain 85-10, a member of one of the species, Xanthomonas euvesicatoria (Xcv has been previously reported. To determine the relationship of the four species at the genome level and to investigate the molecular basis of their virulence and differing host ranges, draft genomic sequences of members of the other three species were determined and compared to strain 85-10. Results We sequenced the genomes of X. vesicatoria (Xv strain 1111 (ATCC 35937, X. perforans (Xp strain 91-118 and X. gardneri (Xg strain 101 (ATCC 19865. The genomes were compared with each other and with the previously sequenced Xcv strain 85-10. In addition, the molecular features were predicted that may be required for pathogenicity including the type III secretion apparatus, type III effectors, other secretion systems, quorum sensing systems, adhesins, extracellular polysaccharide, and lipopolysaccharide determinants. Several novel type III effectors from Xg strain 101 and Xv strain 1111 genomes were computationally identified and their translocation was validated using a reporter gene assay. A homolog to Ax21, the elicitor of XA21-mediated resistance in rice, and a functional Ax21 sulfation system were identified in Xcv. Genes encoding proteins with functions mediated by type II and type IV secretion systems have also been compared, including enzymes involved in cell wall deconstruction, as contributors to pathogenicity. Conclusions Comparative genomic analyses revealed considerable diversity among bacterial spot pathogens, providing new insights into differences and similarities that may explain the diverse nature of these strains. Genes specific to pepper pathogens, such as the O-antigen of the

  10. Comparative genomics reveals diversity among xanthomonads infecting tomato and pepper

    LENUS (Irish Health Repository)

    Potnis, Neha

    2011-03-11

    Abstract Background Bacterial spot of tomato and pepper is caused by four Xanthomonas species and is a major plant disease in warm humid climates. The four species are distinct from each other based on physiological and molecular characteristics. The genome sequence of strain 85-10, a member of one of the species, Xanthomonas euvesicatoria (Xcv) has been previously reported. To determine the relationship of the four species at the genome level and to investigate the molecular basis of their virulence and differing host ranges, draft genomic sequences of members of the other three species were determined and compared to strain 85-10. Results We sequenced the genomes of X. vesicatoria (Xv) strain 1111 (ATCC 35937), X. perforans (Xp) strain 91-118 and X. gardneri (Xg) strain 101 (ATCC 19865). The genomes were compared with each other and with the previously sequenced Xcv strain 85-10. In addition, the molecular features were predicted that may be required for pathogenicity including the type III secretion apparatus, type III effectors, other secretion systems, quorum sensing systems, adhesins, extracellular polysaccharide, and lipopolysaccharide determinants. Several novel type III effectors from Xg strain 101 and Xv strain 1111 genomes were computationally identified and their translocation was validated using a reporter gene assay. A homolog to Ax21, the elicitor of XA21-mediated resistance in rice, and a functional Ax21 sulfation system were identified in Xcv. Genes encoding proteins with functions mediated by type II and type IV secretion systems have also been compared, including enzymes involved in cell wall deconstruction, as contributors to pathogenicity. Conclusions Comparative genomic analyses revealed considerable diversity among bacterial spot pathogens, providing new insights into differences and similarities that may explain the diverse nature of these strains. Genes specific to pepper pathogens, such as the O-antigen of the lipopolysaccharide cluster

  11. Comparative genomics of transcriptional regulation of methionine metabolism in Proteobacteria.

    Directory of Open Access Journals (Sweden)

    Semen A Leyn

    Full Text Available Methionine metabolism and uptake genes in Proteobacteria are controlled by a variety of RNA and DNA regulatory systems. We have applied comparative genomics to reconstruct regulons for three known transcription factors, MetJ, MetR, and SahR, and three known riboswitch motifs, SAH, SAM-SAH, and SAM_alpha, in ∼ 200 genomes from 22 taxonomic groups of Proteobacteria. We also identified two novel regulons: a SahR-like transcription factor SamR controlling various methionine biosynthesis genes in the Xanthomonadales group, and a potential RNA regulatory element with terminator-antiterminator mechanism controlling the metX or metZ genes in beta-proteobacteria. For each analyzed regulator we identified the core, taxon-specific and genome-specific regulon members. By analyzing the distribution of these regulators in bacterial genomes and by comparing their regulon contents we elucidated possible evolutionary scenarios for the regulation of the methionine metabolism genes in Proteobacteria.

  12. Inference of self-regulated transcriptional networks by comparative genomics.

    Science.gov (United States)

    Cornish, Joseph P; Matthews, Fialelei; Thomas, Julien R; Erill, Ivan

    2012-01-01

    The assumption of basic properties, like self-regulation, in simple transcriptional regulatory networks can be exploited to infer regulatory motifs from the growing amounts of genomic and meta-genomic data. These motifs can in principle be used to elucidate the nature and scope of transcriptional networks through comparative genomics. Here we assess the feasibility of this approach using the SOS regulatory network of Gram-positive bacteria as a test case. Using experimentally validated data, we show that the known regulatory motif can be inferred through the assumption of self-regulation. Furthermore, the inferred motif provides a more robust search pattern for comparative genomics than the experimental motifs defined in reference organisms. We take advantage of this robustness to generate a functional map of the SOS response in Gram-positive bacteria. Our results reveal definite differences in the composition of the LexA regulon between Firmicutes and Actinobacteria, and confirm that regulation of cell-division inhibition is a widespread characteristic of this network among Gram-positive bacteria.

  13. Comparative genomics of Enterococcus faecalis from healthy Norwegian infants

    Directory of Open Access Journals (Sweden)

    Nes Ingolf F

    2009-04-01

    Full Text Available Abstract Background Enterococcus faecalis, traditionally considered a harmless commensal of the intestinal tract, is now ranked among the leading causes of nosocomial infections. In an attempt to gain insight into the genetic make-up of commensal E. faecalis, we have studied genomic variation in a collection of community-derived E. faecalis isolated from the feces of Norwegian infants. Results The E. faecalis isolates were first sequence typed by multilocus sequence typing (MLST and characterized with respect to antibiotic resistance and properties associated with virulence. A subset of the isolates was compared to the vancomycin resistant strain E. faecalis V583 (V583 by whole genome microarray comparison (comparative genomic hybridization (CGH. Several of the putative enterococcal virulence factors were found to be highly prevalent among the commensal baby isolates. The genomic variation as observed by CGH was less between isolates displaying the same MLST sequence type than between isolates belonging to different evolutionary lineages. Conclusion The variations in gene content observed among the investigated commensal E. faecalis is comparable to the genetic variation previously reported among strains of various origins thought to be representative of the major E. faecalis lineages. Previous MLST analysis of E. faecalis have identified so-called high-risk enterococcal clonal complexes (HiRECC, defined as genetically distinct subpopulations, epidemiologically associated with enterococcal infections. The observed correlation between CGH and MLST presented here, may offer a method for the identification of lineage-specific genes, and may therefore add clues on how to distinguish pathogenic from commensal E. faecalis. In this work, information on the core genome of E. faecalis is also substantially extended.

  14. A Web-Based Comparative Genomics Tutorial for Investigating Microbial Genomes

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    Michael Strong

    2009-12-01

    Full Text Available As the number of completely sequenced microbial genomes continues to rise at an impressive rate, it is important to prepare students with the skills necessary to investigate microorganisms at the genomic level. As a part of the core curriculum for first-year graduate students in the biological sciences, we have implemented a web-based tutorial to introduce students to the fields of comparative and functional genomics. The tutorial focuses on recent computational methods for identifying functionally linked genes and proteins on a genome-wide scale and was used to introduce students to the Rosetta Stone, Phylogenetic Profile, conserved Gene Neighbor, and Operon computational methods. Students learned to use a number of publicly available web servers and databases to identify functionally linked genes in the Escherichia coli genome, with emphasis on genome organization and operon structure. The overall effectiveness of the tutorial was assessed based on student evaluations and homework assignments. The tutorial is available to other educators at http://www.doe-mbi.ucla.edu/~strong/m253.php.

  15. Genomic characterization of some Iranian children with idiopathic mental retardation using array comparative genomic hybridization

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    Farkhondeh Behjati

    2013-01-01

    Full Text Available Background: Mental retardation (MR has a prevalence of 1-3% and genetic causes are present in more than 50% of patients. Chromosomal abnormalities are one of the most common genetic causes of MR and are responsible for 4-28% of mental retardation. However, the smallest loss or gain of material visible by standard cytogenetic is about 4 Mb and for smaller abnormalities, molecular cytogenetic techniques such as array comparative genomic hybridization (array CGH should be used. It has been shown that 15-25% of idiopathic MR (IMR has submicroscopic rearrangements detectable by array CGH. In this project, the genomic abnormalities were investigated in 32 MR patients using this technique. Materials and Methods: Patients with IMR with dysmorphism were investigated in this study. Karyotype analysis, fragile X and metabolic tests were first carried out on the patients. The copy number variation was then assessed in a total of 32 patients with normal results for the mentioned tests using whole genome oligo array CGH. Multiple ligation probe amplification was carried out as a confirmation test. Results: In total, 19% of the patients showed genomic abnormalities. This is reduced to 12.5% once the two patients with abnormal karyotypes (upon re-evaluation are removed. Conclusion: The array CGH technique increased the detection rate of genomic imbalances in our patients by 12.5%. It is an accurate and reliable method for the determination of genomic imbalances in patients with IMR and dysmorphism.

  16. Comparative analysis of Acinetobacters: three genomes for three lifestyles.

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    David Vallenet

    Full Text Available Acinetobacter baumannii is the source of numerous nosocomial infections in humans and therefore deserves close attention as multidrug or even pandrug resistant strains are increasingly being identified worldwide. Here we report the comparison of two newly sequenced genomes of A. baumannii. The human isolate A. baumannii AYE is multidrug resistant whereas strain SDF, which was isolated from body lice, is antibiotic susceptible. As reference for comparison in this analysis, the genome of the soil-living bacterium A. baylyi strain ADP1 was used. The most interesting dissimilarities we observed were that i whereas strain AYE and A. baylyi genomes harbored very few Insertion Sequence elements which could promote expression of downstream genes, strain SDF sequence contains several hundred of them that have played a crucial role in its genome reduction (gene disruptions and simple DNA loss; ii strain SDF has low catabolic capacities compared to strain AYE. Interestingly, the latter has even higher catabolic capacities than A. baylyi which has already been reported as a very nutritionally versatile organism. This metabolic performance could explain the persistence of A. baumannii nosocomial strains in environments where nutrients are scarce; iii several processes known to play a key role during host infection (biofilm formation, iron uptake, quorum sensing, virulence factors were either different or absent, the best example of which is iron uptake. Indeed, strain AYE and A. baylyi use siderophore-based systems to scavenge iron from the environment whereas strain SDF uses an alternate system similar to the Haem Acquisition System (HAS. Taken together, all these observations suggest that the genome contents of the 3 Acinetobacters compared are partly shaped by life in distinct ecological niches: human (and more largely hospital environment, louse, soil.

  17. Classical Oncogenes and Tumor Suppressor Genes: A Comparative Genomics Perspective

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    Oxana K. Pickeral

    2000-05-01

    Full Text Available We have curated a reference set of cancer-related genes and reanalyzed their sequences in the light of molecular information and resources that have become available since they were first cloned. Homology studies were carried out for human oncogenes and tumor suppressors, compared with the complete proteome of the nematode, Caenorhabditis elegans, and partial proteomes of mouse and rat and the fruit fly, Drosophila melanogaster. Our results demonstrate that simple, semi-automated bioinformatics approaches to identifying putative functionally equivalent gene products in different organisms may often be misleading. An electronic supplement to this article1 provides an integrated view of our comparative genomics analysis as well as mapping data, physical cDNA resources and links to published literature and reviews, thus creating a “window” into the genomes of humans and other organisms for cancer biology.

  18. Floral gene resources from basal angiosperms for comparative genomics research

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    Zhang Xiaohong

    2005-03-01

    Full Text Available Abstract Background The Floral Genome Project was initiated to bridge the genomic gap between the most broadly studied plant model systems. Arabidopsis and rice, although now completely sequenced and under intensive comparative genomic investigation, are separated by at least 125 million years of evolutionary time, and cannot in isolation provide a comprehensive perspective on structural and functional aspects of flowering plant genome dynamics. Here we discuss new genomic resources available to the scientific community, comprising cDNA libraries and Expressed Sequence Tag (EST sequences for a suite of phylogenetically basal angiosperms specifically selected to bridge the evolutionary gaps between model plants and provide insights into gene content and genome structure in the earliest flowering plants. Results Random sequencing of cDNAs from representatives of phylogenetically important eudicot, non-grass monocot, and gymnosperm lineages has so far (as of 12/1/04 generated 70,514 ESTs and 48,170 assembled unigenes. Efficient sorting of EST sequences into putative gene families based on whole Arabidopsis/rice proteome comparison has permitted ready identification of cDNA clones for finished sequencing. Preliminarily, (i proportions of functional categories among sequenced floral genes seem representative of the entire Arabidopsis transcriptome, (ii many known floral gene homologues have been captured, and (iii phylogenetic analyses of ESTs are providing new insights into the process of gene family evolution in relation to the origin and diversification of the angiosperms. Conclusion Initial comparisons illustrate the utility of the EST data sets toward discovery of the basic floral transcriptome. These first findings also afford the opportunity to address a number of conspicuous evolutionary genomic questions, including reproductive organ transcriptome overlap between angiosperms and gymnosperms, genome-wide duplication history, lineage

  19. Streptococcus thermophilus core genome: comparative genome hybridization study of 47 strains.

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    Rasmussen, Thomas Bovbjerg; Danielsen, Morten; Valina, Ondrej; Garrigues, Christel; Johansen, Eric; Pedersen, Martin Bastian

    2008-08-01

    A DNA microarray platform based on 2,200 genes from publicly available sequences was designed for Streptococcus thermophilus. We determined how single-nucleotide polymorphisms in the 65- to 75-mer oligonucleotide probe sequences affect the hybridization signals. The microarrays were then used for comparative genome hybridization (CGH) of 47 dairy S. thermophilus strains. An analysis of the exopolysaccharide genes in each strain confirmed previous findings that this class of genes is indeed highly variable. A phylogenetic tree based on the CGH data showed similar distances for most strains, indicating frequent recombination or gene transfer within S. thermophilus. By comparing genome sizes estimated from the microarrays and pulsed-field gel electrophoresis, the amount of unknown DNA in each strain was estimated. A core genome comprised of 1,271 genes detected in all 47 strains was identified. Likewise, a set of noncore genes detected in only some strains was identified. The concept of an industrial core genome is proposed. This is comprised of the genes in the core genome plus genes that are necessary in an applied industrial context.

  20. Genome analysis and comparative genomics of a Giardia intestinalis assemblage E isolate

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    Andersson Jan O

    2010-10-01

    Full Text Available Abstract Background Giardia intestinalis is a protozoan parasite that causes diarrhea in a wide range of mammalian species. To further understand the genetic diversity between the Giardia intestinalis species, we have performed genome sequencing and analysis of a wild-type Giardia intestinalis sample from the assemblage E group, isolated from a pig. Results We identified 5012 protein coding genes, the majority of which are conserved compared to the previously sequenced genomes of the WB and GS strains in terms of microsynteny and sequence identity. Despite this, there is an unexpectedly large number of chromosomal rearrangements and several smaller structural changes that are present in all chromosomes. Novel members of the VSP, NEK Kinase and HCMP gene families were identified, which may reveal possible mechanisms for host specificity and new avenues for antigenic variation. We used comparative genomics of the three diverse Giardia intestinalis isolates P15, GS and WB to define a core proteome for this species complex and to identify lineage-specific genes. Extensive analyses of polymorphisms in the core proteome of Giardia revealed differential rates of divergence among cellular processes. Conclusions Our results indicate that despite a well conserved core of genes there is significant genome variation between Giardia isolates, both in terms of gene content, gene polymorphisms, structural chromosomal variations and surface molecule repertoires. This study improves the annotation of the Giardia genomes and enables the identification of functionally important variation.

  1. Update on comparative genome mapping between Malus and Pyrus

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    Nishitani Chikako

    2009-09-01

    Full Text Available Abstract Background Comparative genome mapping determines the linkage between homologous genes of related taxa. It has already been used in plants to characterize agronomically important genes in lesser studied species, using information from better studied species. In the Maloideae sub-family, which includes fruit species such as apple, pear, loquat and quince, genome co-linearity has been suggested between the genera Malus and Pyrus; however map comparisons are incomplete to date. Findings Genetic maps for the apple rootstocks 'Malling 9' ('M.9' (Malus × domestica and 'Robusta 5' ('R5' (Malus × robusta, and pear cultivars 'Bartlett' and 'La France' (Pyrus communis were constructed using Simple Sequence Repeat (SSR markers developed from both species, including a new set of 73 pear Expressed Sequence Tag (EST SSR markers. Integrated genetic maps for apple and pear were then constructed using 87 and 131 SSR markers in common, respectively. The genetic maps were aligned using 102 markers in common, including 64 pear SSR markers and 38 apple SSR markers. Of these 102 markers, 90 anchor markers showed complete co-linearity between the two genomes. Conclusion Our alignment of the genetic maps of two Malus cultivars of differing species origin with two Pyrus communis cultivars confirms the ready transferability of SSR markers from one genus to the other and supports a high level of co-linearity within the sub-family Maloideae between the genomes of Malus and Pyrus.

  2. Bamboo Flowering from the Perspective of Comparative Genomics and Transcriptomics.

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    Biswas, Prasun; Chakraborty, Sukanya; Dutta, Smritikana; Pal, Amita; Das, Malay

    2016-01-01

    Bamboos are an important member of the subfamily Bambusoideae, family Poaceae. The plant group exhibits wide variation with respect to the timing (1-120 years) and nature (sporadic vs. gregarious) of flowering among species. Usually flowering in woody bamboos is synchronous across culms growing over a large area, known as gregarious flowering. In many monocarpic bamboos this is followed by mass death and seed setting. While in sporadic flowering an isolated wild clump may flower, set little or no seed and remain alive. Such wide variation in flowering time and extent means that the plant group serves as repositories for genes and expression patterns that are unique to bamboo. Due to the dearth of available genomic and transcriptomic resources, limited studies have been undertaken to identify the potential molecular players in bamboo flowering. The public release of the first bamboo genome sequence Phyllostachys heterocycla, availability of related genomes Brachypodium distachyon and Oryza sativa provide us the opportunity to study this long-standing biological problem in a comparative and functional genomics framework. We identified bamboo genes homologous to those of Oryza and Brachypodium that are involved in established pathways such as vernalization, photoperiod, autonomous, and hormonal regulation of flowering. Additionally, we investigated triggers like stress (drought), physiological maturity and micro RNAs that may play crucial roles in flowering. We also analyzed available transcriptome datasets of different bamboo species to identify genes and their involvement in bamboo flowering. Finally, we summarize potential research hurdles that need to be addressed in future research.

  3. Sequencing and comparative analysis of the gorilla MHC genomic sequence.

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    Wilming, Laurens G; Hart, Elizabeth A; Coggill, Penny C; Horton, Roger; Gilbert, James G R; Clee, Chris; Jones, Matt; Lloyd, Christine; Palmer, Sophie; Sims, Sarah; Whitehead, Siobhan; Wiley, David; Beck, Stephan; Harrow, Jennifer L

    2013-01-01

    Major histocompatibility complex (MHC) genes play a critical role in vertebrate immune response and because the MHC is linked to a significant number of auto-immune and other diseases it is of great medical interest. Here we describe the clone-based sequencing and subsequent annotation of the MHC region of the gorilla genome. Because the MHC is subject to extensive variation, both structural and sequence-wise, it is not readily amenable to study in whole genome shotgun sequence such as the recently published gorilla genome. The variation of the MHC also makes it of evolutionary interest and therefore we analyse the sequence in the context of human and chimpanzee. In our comparisons with human and re-annotated chimpanzee MHC sequence we find that gorilla has a trimodular RCCX cluster, versus the reference human bimodular cluster, and additional copies of Class I (pseudo)genes between Gogo-K and Gogo-A (the orthologues of HLA-K and -A). We also find that Gogo-H (and Patr-H) is coding versus the HLA-H pseudogene and, conversely, there is a Gogo-DQB2 pseudogene versus the HLA-DQB2 coding gene. Our analysis, which is freely available through the VEGA genome browser, provides the research community with a comprehensive dataset for comparative and evolutionary research of the MHC.

  4. Ecology of marine Bacteroidetes: a comparative genomics approach.

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    Fernández-Gómez, Beatriz; Richter, Michael; Schüler, Margarete; Pinhassi, Jarone; Acinas, Silvia G; González, José M; Pedrós-Alió, Carlos

    2013-05-01

    Bacteroidetes are commonly assumed to be specialized in degrading high molecular weight (HMW) compounds and to have a preference for growth attached to particles, surfaces or algal cells. The first sequenced genomes of marine Bacteroidetes seemed to confirm this assumption. Many more genomes have been sequenced recently. Here, a comparative analysis of marine Bacteroidetes genomes revealed a life strategy different from those of other important phyla of marine bacterioplankton such as Cyanobacteria and Proteobacteria. Bacteroidetes have many adaptations to grow attached to particles, have the capacity to degrade polymers, including a large number of peptidases, glycoside hydrolases (GHs), glycosyl transferases, adhesion proteins, as well as the genes for gliding motility. Several of the polymer degradation genes are located in close association with genes for TonB-dependent receptors and transducers, suggesting an integrated regulation of adhesion and degradation of polymers. This confirmed the role of this abundant group of marine bacteria as degraders of particulate matter. Marine Bacteroidetes had a significantly larger number of proteases than GHs, while non-marine Bacteroidetes had equal numbers of both. Proteorhodopsin containing Bacteroidetes shared two characteristics: small genome size and a higher number of genes involved in CO2 fixation per Mb. The latter may be important in order to survive when floating freely in the illuminated, but nutrient-poor, ocean surface.

  5. Whole-genome sequence of the Tibetan frog Nanorana parkeri and the comparative evolution of tetrapod genomes.

    Science.gov (United States)

    Sun, Yan-Bo; Xiong, Zi-Jun; Xiang, Xue-Yan; Liu, Shi-Ping; Zhou, Wei-Wei; Tu, Xiao-Long; Zhong, Li; Wang, Lu; Wu, Dong-Dong; Zhang, Bao-Lin; Zhu, Chun-Ling; Yang, Min-Min; Chen, Hong-Man; Li, Fang; Zhou, Long; Feng, Shao-Hong; Huang, Chao; Zhang, Guo-Jie; Irwin, David; Hillis, David M; Murphy, Robert W; Yang, Huan-Ming; Che, Jing; Wang, Jun; Zhang, Ya-Ping

    2015-03-17

    The development of efficient sequencing techniques has resulted in large numbers of genomes being available for evolutionary studies. However, only one genome is available for all amphibians, that of Xenopus tropicalis, which is distantly related from the majority of frogs. More than 96% of frogs belong to the Neobatrachia, and no genome exists for this group. This dearth of amphibian genomes greatly restricts genomic studies of amphibians and, more generally, our understanding of tetrapod genome evolution. To fill this gap, we provide the de novo genome of a Tibetan Plateau frog, Nanorana parkeri, and compare it to that of X. tropicalis and other vertebrates. This genome encodes more than 20,000 protein-coding genes, a number similar to that of Xenopus. Although the genome size of Nanorana is considerably larger than that of Xenopus (2.3 vs. 1.5 Gb), most of the difference is due to the respective number of transposable elements in the two genomes. The two frogs exhibit considerable conserved whole-genome synteny despite having diverged approximately 266 Ma, indicating a slow rate of DNA structural evolution in anurans. Multigenome synteny blocks further show that amphibians have fewer interchromosomal rearrangements than mammals but have a comparable rate of intrachromosomal rearrangements. Our analysis also identifies 11 Mb of anuran-specific highly conserved elements that will be useful for comparative genomic analyses of frogs. The Nanorana genome offers an improved understanding of evolution of tetrapod genomes and also provides a genomic reference for other evolutionary studies.

  6. Microarray comparative genomic hybridisation analysis incorporating genomic organisation, and application to enterobacterial plant pathogens.

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    Leighton Pritchard

    2009-08-01

    Full Text Available Microarray comparative genomic hybridisation (aCGH provides an estimate of the relative abundance of genomic DNA (gDNA taken from comparator and reference organisms by hybridisation to a microarray containing probes that represent sequences from the reference organism. The experimental method is used in a number of biological applications, including the detection of human chromosomal aberrations, and in comparative genomic analysis of bacterial strains, but optimisation of the analysis is desirable in each problem domain.We present a method for analysis of bacterial aCGH data that encodes spatial information from the reference genome in a hidden Markov model. This technique is the first such method to be validated in comparisons of sequenced bacteria that diverge at the strain and at the genus level: Pectobacterium atrosepticum SCRI1043 (Pba1043 and Dickeya dadantii 3937 (Dda3937; and Lactococcus lactis subsp. lactis IL1403 and L. lactis subsp. cremoris MG1363. In all cases our method is found to outperform common and widely used aCGH analysis methods that do not incorporate spatial information. This analysis is applied to comparisons between commercially important plant pathogenic soft-rotting enterobacteria (SRE Pba1043, P. atrosepticum SCRI1039, P. carotovorum 193, and Dda3937.Our analysis indicates that it should not be assumed that hybridisation strength is a reliable proxy for sequence identity in aCGH experiments, and robustly extends the applicability of aCGH to bacterial comparisons at the genus level. Our results in the SRE further provide evidence for a dynamic, plastic 'accessory' genome, revealing major genomic islands encoding gene products that provide insight into, and may play a direct role in determining, variation amongst the SRE in terms of their environmental survival, host range and aetiology, such as phytotoxin synthesis, multidrug resistance, and nitrogen fixation.

  7. The genome sequence of Caenorhabditis briggsae: a platform for comparative genomics.

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    Lincoln D Stein

    2003-11-01

    Full Text Available The soil nematodes Caenorhabditis briggsae and Caenorhabditis elegans diverged from a common ancestor roughly 100 million years ago and yet are almost indistinguishable by eye. They have the same chromosome number and genome sizes, and they occupy the same ecological niche. To explore the basis for this striking conservation of structure and function, we have sequenced the C. briggsae genome to a high-quality draft stage and compared it to the finished C. elegans sequence. We predict approximately 19,500 protein-coding genes in the C. briggsae genome, roughly the same as in C. elegans. Of these, 12,200 have clear C. elegans orthologs, a further 6,500 have one or more clearly detectable C. elegans homologs, and approximately 800 C. briggsae genes have no detectable matches in C. elegans. Almost all of the noncoding RNAs (ncRNAs known are shared between the two species. The two genomes exhibit extensive colinearity, and the rate of divergence appears to be higher in the chromosomal arms than in the centers. Operons, a distinctive feature of C. elegans, are highly conserved in C. briggsae, with the arrangement of genes being preserved in 96% of cases. The difference in size between the C. briggsae (estimated at approximately 104 Mbp and C. elegans (100.3 Mbp genomes is almost entirely due to repetitive sequence, which accounts for 22.4% of the C. briggsae genome in contrast to 16.5% of the C. elegans genome. Few, if any, repeat families are shared, suggesting that most were acquired after the two species diverged or are undergoing rapid evolution. Coclustering the C. elegans and C. briggsae proteins reveals 2,169 protein families of two or more members. Most of these are shared between the two species, but some appear to be expanding or contracting, and there seem to be as many as several hundred novel C. briggsae gene families. The C. briggsae draft sequence will greatly improve the annotation of the C. elegans genome. Based on similarity to C

  8. Diversity of Pseudomonas Genomes, Including Populus-Associated Isolates, as Revealed by Comparative Genome Analysis.

    Science.gov (United States)

    Jun, Se-Ran; Wassenaar, Trudy M; Nookaew, Intawat; Hauser, Loren; Wanchai, Visanu; Land, Miriam; Timm, Collin M; Lu, Tse-Yuan S; Schadt, Christopher W; Doktycz, Mitchel J; Pelletier, Dale A; Ussery, David W

    2015-10-30

    The Pseudomonas genus contains a metabolically versatile group of organisms that are known to occupy numerous ecological niches, including the rhizosphere and endosphere of many plants. Their diversity influences the phylogenetic diversity and heterogeneity of these communities. On the basis of average amino acid identity, comparative genome analysis of >1,000 Pseudomonas genomes, including 21 Pseudomonas strains isolated from the roots of native Populus deltoides (eastern cottonwood) trees resulted in consistent and robust genomic clusters with phylogenetic homogeneity. All Pseudomonas aeruginosa genomes clustered together, and these were clearly distinct from other Pseudomonas species groups on the basis of pangenome and core genome analyses. In contrast, the genomes of Pseudomonas fluorescens were organized into 20 distinct genomic clusters, representing enormous diversity and heterogeneity. Most of our 21 Populus-associated isolates formed three distinct subgroups within the major P. fluorescens group, supported by pathway profile analysis, while two isolates were more closely related to Pseudomonas chlororaphis and Pseudomonas putida. Genes specific to Populus-associated subgroups were identified. Genes specific to subgroup 1 include several sensory systems that act in two-component signal transduction, a TonB-dependent receptor, and a phosphorelay sensor. Genes specific to subgroup 2 contain hypothetical genes, and genes specific to subgroup 3 were annotated with hydrolase activity. This study justifies the need to sequence multiple isolates, especially from P. fluorescens, which displays the most genetic variation, in order to study functional capabilities from a pangenomic perspective. This information will prove useful when choosing Pseudomonas strains for use to promote growth and increase disease resistance in plants.

  9. A hybrid computational grid architecture for comparative genomics.

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    Singh, Aarti; Chen, Chen; Liu, Weiguo; Mitchell, Wayne; Schmidt, Bertil

    2008-03-01

    Comparative genomics provides a powerful tool for studying evolutionary changes among organisms, helping to identify genes that are conserved among species, as well as genes that give each organism its unique characteristics. However, the huge datasets involved makes this approach impractical on traditional computer architectures leading to prohibitively long runtimes. In this paper, we present a new computational grid architecture based on a hybrid computing model to significantly accelerate comparative genomics applications. The hybrid computing model consists of two types of parallelism: coarse grained and fine grained. The coarse-grained parallelism uses a volunteer computing infrastructure for job distribution, while the fine-grained parallelism uses commodity computer graphics hardware for fast sequence alignment. We present the deployment and evaluation of this approach on our grid test bed for the all-against-all comparison of microbial genomes. The results of this comparison are then used by phenotype--genotype explorer (PheGee). PheGee is a new tool that nominates candidate genes responsible for a given phenotype.

  10. The genome sequence of Blochmannia floridanus: Comparative analysis of reduced genomes

    Science.gov (United States)

    Gil, Rosario; Silva, Francisco J.; Zientz, Evelyn; Delmotte, François; González-Candelas, Fernando; Latorre, Amparo; Rausell, Carolina; Kamerbeek, Judith; Gadau, Jürgen; Hölldobler, Bert; van Ham, Roeland C. H. J.; Gross, Roy; Moya, Andrés

    2003-01-01

    Bacterial symbioses are widespread among insects, probably being one of the key factors of their evolutionary success. We present the complete genome sequence of Blochmannia floridanus, the primary endosymbiont of carpenter ants. Although these ants feed on a complex diet, this symbiosis very likely has a nutritional basis: Blochmannia is able to supply nitrogen and sulfur compounds to the host while it takes advantage of the host metabolic machinery. Remarkably, these bacteria lack all known genes involved in replication initiation (dnaA, priA, and recA). The phylogenetic analysis of a set of conserved protein-coding genes shows that Bl. floridanus is phylogenetically related to Buchnera aphidicola and Wigglesworthia glossinidia, the other endosymbiotic bacteria whose complete genomes have been sequenced so far. Comparative analysis of the five known genomes from insect endosymbiotic bacteria reveals they share only 313 genes, a number that may be close to the minimum gene set necessary to sustain endosymbiotic life. PMID:12886019

  11. Genomic analysis by oligonucleotide array Comparative Genomic Hybridization utilizing formalin-fixed, paraffin-embedded tissues.

    Science.gov (United States)

    Savage, Stephanie J; Hostetter, Galen

    2011-01-01

    Formalin fixation has been used to preserve tissues for more than a hundred years, and there are currently more than 300 million archival samples in the United States alone. The application of genomic protocols such as high-density oligonucleotide array Comparative Genomic Hybridization (aCGH) to formalin-fixed, paraffin-embedded (FFPE) tissues, therefore, opens an untapped resource of available tissues for research and facilitates utilization of existing clinical data in a research sample set. However, formalin fixation results in cross-linking of proteins and DNA, typically leading to such a significant degradation of DNA template that little is available for use in molecular applications. Here, we describe a protocol to circumvent formalin fixation artifact by utilizing enzymatic reactions to obtain quality DNA from a wide range of FFPE tissues for successful genome-wide discovery of gene dosage alterations in archival clinical samples.

  12. Comparative genome analysis of Bacillus cereus group genomes withBacillus subtilis

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Iain; Sorokin, Alexei; Kapatral, Vinayak; Reznik, Gary; Bhattacharya, Anamitra; Mikhailova, Natalia; Burd, Henry; Joukov, Victor; Kaznadzey, Denis; Walunas, Theresa; D' Souza, Mark; Larsen, Niels; Pusch,Gordon; Liolios, Konstantinos; Grechkin, Yuri; Lapidus, Alla; Goltsman,Eugene; Chu, Lien; Fonstein, Michael; Ehrlich, S. Dusko; Overbeek, Ross; Kyrpides, Nikos; Ivanova, Natalia

    2005-09-14

    Genome features of the Bacillus cereus group genomes (representative strains of Bacillus cereus, Bacillus anthracis and Bacillus thuringiensis sub spp israelensis) were analyzed and compared with the Bacillus subtilis genome. A core set of 1,381 protein families among the four Bacillus genomes, with an additional set of 933 families common to the B. cereus group, was identified. Differences in signal transduction pathways, membrane transporters, cell surface structures, cell wall, and S-layer proteins suggesting differences in their phenotype were identified. The B. cereus group has signal transduction systems including a tyrosine kinase related to two-component system histidine kinases from B. subtilis. A model for regulation of the stress responsive sigma factor sigmaB in the B. cereus group different from the well studied regulation in B. subtilis has been proposed. Despite a high degree of chromosomal synteny among these genomes, significant differences in cell wall and spore coat proteins that contribute to the survival and adaptation in specific hosts has been identified.

  13. Reduction and expansion in microsporidian genome evolution: new insights from comparative genomics.

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    Nakjang, Sirintra; Williams, Tom A; Heinz, Eva; Watson, Andrew K; Foster, Peter G; Sendra, Kacper M; Heaps, Sarah E; Hirt, Robert P; Martin Embley, T

    2013-01-01

    Microsporidia are an abundant group of obligate intracellular parasites of other eukaryotes, including immunocompromised humans, but the molecular basis of their intracellular lifestyle and pathobiology are poorly understood. New genomes from a taxonomically broad range of microsporidians, complemented by published expression data, provide an opportunity for comparative analyses to identify conserved and lineage-specific patterns of microsporidian genome evolution that have underpinned this success. In this study, we infer that a dramatic bottleneck in the last common microsporidian ancestor (LCMA) left a small conserved core of genes that was subsequently embellished by gene family expansion driven by gene acquisition in different lineages. Novel expressed protein families represent a substantial fraction of sequenced microsporidian genomes and are significantly enriched for signals consistent with secretion or membrane location. Further evidence of selection is inferred from the gain and reciprocal loss of functional domains between paralogous genes, for example, affecting transport proteins. Gene expansions among transporter families preferentially affect those that are located on the plasma membrane of model organisms, consistent with recruitment to plug conserved gaps in microsporidian biosynthesis and metabolism. Core microsporidian genes shared with other eukaryotes are enriched in orthologs that, in yeast, are highly expressed, highly connected, and often essential, consistent with strong negative selection against further reduction of the conserved gene set since the LCMA. Our study reveals that microsporidian genome evolution is a highly dynamic process that has balanced constraint, reductive evolution, and genome expansion during adaptation to an extraordinarily successful obligate intracellular lifestyle.

  14. A comparative encyclopedia of DNA elements in the mouse genome.

    Science.gov (United States)

    Yue, Feng; Cheng, Yong; Breschi, Alessandra; Vierstra, Jeff; Wu, Weisheng; Ryba, Tyrone; Sandstrom, Richard; Ma, Zhihai; Davis, Carrie; Pope, Benjamin D; Shen, Yin; Pervouchine, Dmitri D; Djebali, Sarah; Thurman, Robert E; Kaul, Rajinder; Rynes, Eric; Kirilusha, Anthony; Marinov, Georgi K; Williams, Brian A; Trout, Diane; Amrhein, Henry; Fisher-Aylor, Katherine; Antoshechkin, Igor; DeSalvo, Gilberto; See, Lei-Hoon; Fastuca, Meagan; Drenkow, Jorg; Zaleski, Chris; Dobin, Alex; Prieto, Pablo; Lagarde, Julien; Bussotti, Giovanni; Tanzer, Andrea; Denas, Olgert; Li, Kanwei; Bender, M A; Zhang, Miaohua; Byron, Rachel; Groudine, Mark T; McCleary, David; Pham, Long; Ye, Zhen; Kuan, Samantha; Edsall, Lee; Wu, Yi-Chieh; Rasmussen, Matthew D; Bansal, Mukul S; Kellis, Manolis; Keller, Cheryl A; Morrissey, Christapher S; Mishra, Tejaswini; Jain, Deepti; Dogan, Nergiz; Harris, Robert S; Cayting, Philip; Kawli, Trupti; Boyle, Alan P; Euskirchen, Ghia; Kundaje, Anshul; Lin, Shin; Lin, Yiing; Jansen, Camden; Malladi, Venkat S; Cline, Melissa S; Erickson, Drew T; Kirkup, Vanessa M; Learned, Katrina; Sloan, Cricket A; Rosenbloom, Kate R; Lacerda de Sousa, Beatriz; Beal, Kathryn; Pignatelli, Miguel; Flicek, Paul; Lian, Jin; Kahveci, Tamer; Lee, Dongwon; Kent, W James; Ramalho Santos, Miguel; Herrero, Javier; Notredame, Cedric; Johnson, Audra; Vong, Shinny; Lee, Kristen; Bates, Daniel; Neri, Fidencio; Diegel, Morgan; Canfield, Theresa; Sabo, Peter J; Wilken, Matthew S; Reh, Thomas A; Giste, Erika; Shafer, Anthony; Kutyavin, Tanya; Haugen, Eric; Dunn, Douglas; Reynolds, Alex P; Neph, Shane; Humbert, Richard; Hansen, R Scott; De Bruijn, Marella; Selleri, Licia; Rudensky, Alexander; Josefowicz, Steven; Samstein, Robert; Eichler, Evan E; Orkin, Stuart H; Levasseur, Dana; Papayannopoulou, Thalia; Chang, Kai-Hsin; Skoultchi, Arthur; Gosh, Srikanta; Disteche, Christine; Treuting, Piper; Wang, Yanli; Weiss, Mitchell J; Blobel, Gerd A; Cao, Xiaoyi; Zhong, Sheng; Wang, Ting; Good, Peter J; Lowdon, Rebecca F; Adams, Leslie B; Zhou, Xiao-Qiao; Pazin, Michael J; Feingold, Elise A; Wold, Barbara; Taylor, James; Mortazavi, Ali; Weissman, Sherman M; Stamatoyannopoulos, John A; Snyder, Michael P; Guigo, Roderic; Gingeras, Thomas R; Gilbert, David M; Hardison, Ross C; Beer, Michael A; Ren, Bing

    2014-11-20

    The laboratory mouse shares the majority of its protein-coding genes with humans, making it the premier model organism in biomedical research, yet the two mammals differ in significant ways. To gain greater insights into both shared and species-specific transcriptional and cellular regulatory programs in the mouse, the Mouse ENCODE Consortium has mapped transcription, DNase I hypersensitivity, transcription factor binding, chromatin modifications and replication domains throughout the mouse genome in diverse cell and tissue types. By comparing with the human genome, we not only confirm substantial conservation in the newly annotated potential functional sequences, but also find a large degree of divergence of sequences involved in transcriptional regulation, chromatin state and higher order chromatin organization. Our results illuminate the wide range of evolutionary forces acting on genes and their regulatory regions, and provide a general resource for research into mammalian biology and mechanisms of human diseases.

  15. Beyond the thale: comparative genomics and genetics of Arabidopsis relatives.

    Science.gov (United States)

    Koenig, Daniel; Weigel, Detlef

    2015-05-01

    For decades a small number of model species have rightly occupied a privileged position in laboratory experiments, but it is becoming increasingly clear that our knowledge of biology is greatly improved when informed by a broader diversity of species and evolutionary context. Arabidopsis thaliana has been the primary model organism for plants, benefiting from a high-quality reference genome sequence and resources for reverse genetics. However, recent studies have made a group of species also in the Brassicaceae family and closely related to A. thaliana a focal point for comparative molecular, genomic, phenotypic and evolutionary studies. In this Review, we emphasize how such studies complement continued study of the model plant itself, provide an evolutionary perspective and summarize our current understanding of genetic and phenotypic diversity in plants.

  16. A Comparative Encyclopedia of DNA Elements in the Mouse Genome

    Science.gov (United States)

    Yue, Feng; Cheng, Yong; Breschi, Alessandra; Vierstra, Jeff; Wu, Weisheng; Ryba, Tyrone; Sandstrom, Richard; Ma, Zhihai; Davis, Carrie; Pope, Benjamin D.; Shen, Yin; Pervouchine, Dmitri D.; Djebali, Sarah; Thurman, Bob; Kaul, Rajinder; Rynes, Eric; Kirilusha, Anthony; Marinov, Georgi K.; Williams, Brian A.; Trout, Diane; Amrhein, Henry; Fisher-Aylor, Katherine; Antoshechkin, Igor; DeSalvo, Gilberto; See, Lei-Hoon; Fastuca, Meagan; Drenkow, Jorg; Zaleski, Chris; Dobin, Alex; Prieto, Pablo; Lagarde, Julien; Bussotti, Giovanni; Tanzer, Andrea; Denas, Olgert; Li, Kanwei; Bender, M. A.; Zhang, Miaohua; Byron, Rachel; Groudine, Mark T.; McCleary, David; Pham, Long; Ye, Zhen; Kuan, Samantha; Edsall, Lee; Wu, Yi-Chieh; Rasmussen, Matthew D.; Bansal, Mukul S.; Keller, Cheryl A.; Morrissey, Christapher S.; Mishra, Tejaswini; Jain, Deepti; Dogan, Nergiz; Harris, Robert S.; Cayting, Philip; Kawli, Trupti; Boyle, Alan P.; Euskirchen, Ghia; Kundaje, Anshul; Lin, Shin; Lin, Yiing; Jansen, Camden; Malladi, Venkat S.; Cline, Melissa S.; Erickson, Drew T.; Kirkup, Vanessa M; Learned, Katrina; Sloan, Cricket A.; Rosenbloom, Kate R.; de Sousa, Beatriz Lacerda; Beal, Kathryn; Pignatelli, Miguel; Flicek, Paul; Lian, Jin; Kahveci, Tamer; Lee, Dongwon; Kent, W. James; Santos, Miguel Ramalho; Herrero, Javier; Notredame, Cedric; Johnson, Audra; Vong, Shinny; Lee, Kristen; Bates, Daniel; Neri, Fidencio; Diegel, Morgan; Canfield, Theresa; Sabo, Peter J.; Wilken, Matthew S.; Reh, Thomas A.; Giste, Erika; Shafer, Anthony; Kutyavin, Tanya; Haugen, Eric; Dunn, Douglas; Reynolds, Alex P.; Neph, Shane; Humbert, Richard; Hansen, R. Scott; De Bruijn, Marella; Selleri, Licia; Rudensky, Alexander; Josefowicz, Steven; Samstein, Robert; Eichler, Evan E.; Orkin, Stuart H.; Levasseur, Dana; Papayannopoulou, Thalia; Chang, Kai-Hsin; Skoultchi, Arthur; Gosh, Srikanta; Disteche, Christine; Treuting, Piper; Wang, Yanli; Weiss, Mitchell J.; Blobel, Gerd A.; Good, Peter J.; Lowdon, Rebecca F.; Adams, Leslie B.; Zhou, Xiao-Qiao; Pazin, Michael J.; Feingold, Elise A.; Wold, Barbara; Taylor, James; Kellis, Manolis; Mortazavi, Ali; Weissman, Sherman M.; Stamatoyannopoulos, John; Snyder, Michael P.; Guigo, Roderic; Gingeras, Thomas R.; Gilbert, David M.; Hardison, Ross C.; Beer, Michael A.; Ren, Bing

    2014-01-01

    Summary As the premier model organism in biomedical research, the laboratory mouse shares the majority of protein-coding genes with humans, yet the two mammals differ in significant ways. To gain greater insights into both shared and species-specific transcriptional and cellular regulatory programs in the mouse, the Mouse ENCODE Consortium has mapped transcription, DNase I hypersensitivity, transcription factor binding, chromatin modifications, and replication domains throughout the mouse genome in diverse cell and tissue types. By comparing with the human genome, we not only confirm substantial conservation in the newly annotated potential functional sequences, but also find a large degree of divergence of other sequences involved in transcriptional regulation, chromatin state and higher order chromatin organization. Our results illuminate the wide range of evolutionary forces acting on genes and their regulatory regions, and provide a general resource for research into mammalian biology and mechanisms of human diseases. PMID:25409824

  17. Comparative Genomics of the Ubiquitous, Hydrocarbon-degrading Genus Marinobacter

    Science.gov (United States)

    Singer, E.; Webb, E.; Edwards, K. J.

    2012-12-01

    The genus Marinobacter is amongst the most ubiquitous in the global oceans and strains have been isolated from a wide variety of marine environments, including offshore oil-well heads, coastal thermal springs, Antarctic sea water, saline soils and associations with diatoms and dinoflagellates. Many strains have been recognized to be important hydrocarbon degraders in various marine habitats presenting sometimes extreme pH or salinity conditions. Analysis of the genome of M. aquaeolei revealed enormous adaptation versatility with an assortment of strategies for carbon and energy acquisition, sensation, and defense. In an effort to elucidate the ecological and biogeochemical significance of the Marinobacters, seven Marinobacter strains from diverse environments were included in a comparative genomics study. Genomes were screened for metabolic and adaptation potential to elucidate the strategies responsible for the omnipresence of the Marinobacter genus and their remedial action potential in hydrocarbon-polluted waters. The core genome predominantly encodes for key genes involved in hydrocarbon degradation, biofilm-relevant processes, including utilization of external DNA, halotolerance, as well as defense mechanisms against heavy metals, antibiotics, and toxins. All Marinobacter strains were observed to degrade a wide spectrum of hydrocarbon species, including aliphatic, polycyclic aromatic as well as acyclic isoprenoid compounds. Various genes predicted to facilitate hydrocarbon degradation, e.g. alkane 1-monooxygenase, appear to have originated from lateral gene transfer as they are located on gene clusters of 10-20% lower GC-content compared to genome averages and are flanked by transposases. Top ortholog hits are found in other hydrocarbon degrading organisms, e.g. Alcanivorax borkumensis. Strategies for hydrocarbon uptake encoded by various Marinobacter strains include cell surface hydrophobicity adaptation via capsular polysaccharide biosynthesis and attachment

  18. Comparative genomics of Serratia spp.: two paths towards endosymbiotic life.

    Directory of Open Access Journals (Sweden)

    Alejandro Manzano-Marín

    Full Text Available Symbiosis is a widespread phenomenon in nature, in which insects show a great number of these associations. Buchnera aphidicola, the obligate endosymbiont of aphids, coexists in some species with another intracellular bacterium, Serratia symbiotica. Of particular interest is the case of the cedar aphid Cinara cedri, where B. aphidicola BCc and S. symbiotica SCc need each other to fulfil their symbiotic role with the insect. Moreover, various features seem to indicate that S. symbiotica SCc is closer to an obligate endosymbiont than to other facultative S. symbiotica, such as the one described for the aphid Acirthosyphon pisum (S. symbiotica SAp. This work is based on the comparative genomics of five strains of Serratia, three free-living and two endosymbiotic ones (one facultative and one obligate which should allow us to dissect the genome reduction taking place in the adaptive process to an intracellular life-style. Using a pan-genome approach, we have identified shared and strain-specific genes from both endosymbiotic strains and gained insight into the different genetic reduction both S. symbiotica have undergone. We have identified both retained and reduced functional categories in S. symbiotica compared to the Free-Living Serratia (FLS that seem to be related with its endosymbiotic role in their specific host-symbiont systems. By means of a phylogenomic reconstruction we have solved the position of both endosymbionts with confidence, established the probable insect-pathogen origin of the symbiotic clade as well as the high amino-acid substitution rate in S. symbiotica SCc. Finally, we were able to quantify the minimal number of rearrangements suffered in the endosymbiotic lineages and reconstruct a minimal rearrangement phylogeny. All these findings provide important evidence for the existence of at least two distinctive S. symbiotica lineages that are characterized by different rearrangements, gene content, genome size and branch lengths.

  19. Array comparative genomic hybridization in retinoma and retinoblastoma tissues.

    Science.gov (United States)

    Sampieri, Katia; Amenduni, Mariangela; Papa, Filomena Tiziana; Katzaki, Eleni; Mencarelli, Maria Antonietta; Marozza, Annabella; Epistolato, Maria Carmela; Toti, Paolo; Lazzi, Stefano; Bruttini, Mirella; De Filippis, Roberta; De Francesco, Sonia; Longo, Ilaria; Meloni, Ilaria; Mari, Francesca; Acquaviva, Antonio; Hadjistilianou, Theodora; Renieri, Alessandra; Ariani, Francesca

    2009-03-01

    In retinoblastoma, two RB1 mutations are necessary for tumor development. Recurrent genomic rearrangements may represent subsequent events required for retinoblastoma progression. Array-comparative genomic hybridization was carried out in 18 eye samples, 10 from bilateral and eight from unilateral retinoblastoma patients. Two unilateral cases also showed areas of retinoma. The most frequent imbalance in retinoblastomas was 6p gain (40%), followed by gains at 1q12-q25.3, 2p24.3-p24.2, 9q22.2, and 9q33.1 and losses at 11q24.3, 13q13.2-q22.3, and 16q12.1-q21. Bilateral cases showed a lower number of imbalances than unilateral cases (P = 0.002). Unilateral cases were divided into low-level ( or = 7) chromosomal instability groups. The first group presented with younger age at diagnosis (mean 511 days) compared with the second group (mean 1606 days). In one retinoma case ophthalmoscopically diagnosed as a benign lesion no rearrangements were detected, whereas the adjacent retinoblastoma displayed seven aberrations. The other retinoma case identified by retrospective histopathological examination shared three rearrangements with the adjacent retinoblastoma. Two other gene-free rearrangements were retinoma specific. One rearrangement, dup5p, was retinoblastoma specific and included the SKP2 gene. Genomic profiling indicated that the first retinoma was a pretumoral lesion, whereas the other represents a subclone of cells bearing 'benign' rearrangements overwhelmed by another subclone presenting aberrations with higher 'oncogenic' potential. In summary, the present study shows that bilateral and unilateral retinoblastoma have different chromosomal instability that correlates with the age of tumor onset in unilateral cases. This is the first report of genomic profiling in retinoma tissue, shedding light on the different nature of lesions named 'retinoma'.

  20. Comparative Genomics of the Listeria monocytogenes ST204 Subgroup.

    Science.gov (United States)

    Fox, Edward M; Allnutt, Theodore; Bradbury, Mark I; Fanning, Séamus; Chandry, P Scott

    2016-01-01

    The ST204 subgroup of Listeria monocytogenes is among the most frequently isolated in Australia from a range of environmental niches. In this study we provide a comparative genomics analysis of food and food environment isolates from geographically diverse sources. Analysis of the ST204 genomes showed a highly conserved core genome with the majority of variation seen in mobile genetic elements such as plasmids, transposons and phage insertions. Most strains (13/15) harbored plasmids, which although varying in size contained highly conserved sequences. Interestingly 4 isolates contained a conserved plasmid of 91,396 bp. The strains examined were isolated over a period of 12 years and from different geographic locations suggesting plasmids are an important component of the genetic repertoire of this subgroup and may provide a range of stress tolerance mechanisms. In addition to this 4 phage insertion sites and 2 transposons were identified among isolates, including a novel transposon. These genetic elements were highly conserved across isolates that harbored them, and also contained a range of genetic markers linked to stress tolerance and virulence. The maintenance of conserved mobile genetic elements in the ST204 population suggests these elements may contribute to the diverse range of niches colonized by ST204 isolates. Environmental stress selection may contribute to maintaining these genetic features, which in turn may be co-selecting for virulence markers relevant to clinical infection with ST204 isolates.

  1. Comparative genomics reveals mobile pathogenicity chromosomes in Fusarium

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Li Jun; van der Does, H. C.; Borkovich, Katherine A.; Coleman, Jeffrey J.; Daboussi, Marie-Jose; Di Pietro, Antonio; Dufresne, Marie; Freitag, Michael; Grabherr, Manfred; Henrissat, Bernard; Houterman, Petra M.; Kang, Seogchan; Shim, Won-Bo; Wolochuk, Charles; Xie, Xiaohui; Xu, Jin Rong; Antoniw, John; Baker, Scott E.; Bluhm, Burton H.; Breakspear, Andrew; Brown, Daren W.; Butchko, Robert A.; Chapman, Sinead; Coulson, Richard; Coutinho, Pedro M.; Danchin, Etienne G.; Diener, Andrew; Gale, Liane R.; Gardiner, Donald; Goff, Steven; Hammond-Kossack, Kim; Hilburn, Karen; Hua-Van, Aurelie; Jonkers, Wilfried; Kazan, Kemal; Kodira, Chinnappa D.; Koehrsen, Michael; Kumar, Lokesh; Lee, Yong Hwan; Li, Liande; Manners, John M.; Miranda-Saavedra, Diego; Mukherjee, Mala; Park, Gyungsoon; Park, Jongsun; Park, Sook Young; Proctor, Robert H.; Regev, Aviv; Ruiz-Roldan, M. C.; Sain, Divya; Sakthikumar, Sharadha; Sykes, Sean; Schwartz, David C.; Turgeon, Barbara G.; Wapinski, Ilan; Yoder, Olen; Young, Sarah; Zeng, Qiandong; Zhou, Shiguo; Galagan, James; Cuomo, Christina A.; Kistler, H. Corby; Rep, Martijn

    2010-03-18

    Fusarium species are among the most important phytopathogenic and toxigenic fungi, having significant impact on crop production and animal health. Distinctively, members of the F. oxysporum species complex exhibit wide host range but discontinuously distributed host specificity, reflecting remarkable genetic adaptability. To understand the molecular underpinnings of diverse phenotypic traits and their evolution in Fusarium, we compared the genomes of three economically important and phylogenetically related, yet phenotypically diverse plant-pathogenic species, F. graminearum, F. verticillioides and F. oxysporum f. sp. lycopersici. Our analysis revealed greatly expanded lineage-specific (LS) genomic regions in F. oxysporum that include four entire chromosomes, accounting for more than one-quarter of the genome. LS regions are rich in transposons and genes with distinct evolutionary profiles but related to pathogenicity. Experimentally, we demonstrate for the first time the transfer of two LS chromosomes between strains of F. oxysporum, resulting in the conversion of a non-pathogenic strain into a pathogen. Transfer of LS chromosomes between otherwise genetically isolated strains explains the polyphyletic origin of host specificity and the emergence of new pathogenic lineages in the F. oxysporum species complex, putting the evolution of fungal pathogenicity into a new perspective.

  2. Comparative Genomics of the Listeria monocytogenes ST204 Subgroup

    Science.gov (United States)

    Fox, Edward M.; Allnutt, Theodore; Bradbury, Mark I.; Fanning, Séamus; Chandry, P. Scott

    2016-01-01

    The ST204 subgroup of Listeria monocytogenes is among the most frequently isolated in Australia from a range of environmental niches. In this study we provide a comparative genomics analysis of food and food environment isolates from geographically diverse sources. Analysis of the ST204 genomes showed a highly conserved core genome with the majority of variation seen in mobile genetic elements such as plasmids, transposons and phage insertions. Most strains (13/15) harbored plasmids, which although varying in size contained highly conserved sequences. Interestingly 4 isolates contained a conserved plasmid of 91,396 bp. The strains examined were isolated over a period of 12 years and from different geographic locations suggesting plasmids are an important component of the genetic repertoire of this subgroup and may provide a range of stress tolerance mechanisms. In addition to this 4 phage insertion sites and 2 transposons were identified among isolates, including a novel transposon. These genetic elements were highly conserved across isolates that harbored them, and also contained a range of genetic markers linked to stress tolerance and virulence. The maintenance of conserved mobile genetic elements in the ST204 population suggests these elements may contribute to the diverse range of niches colonized by ST204 isolates. Environmental stress selection may contribute to maintaining these genetic features, which in turn may be co-selecting for virulence markers relevant to clinical infection with ST204 isolates. PMID:28066377

  3. Comparative genomics of flatworms (platyhelminthes) reveals shared genomic features of ecto- and endoparastic neodermata.

    Science.gov (United States)

    Hahn, Christoph; Fromm, Bastian; Bachmann, Lutz

    2014-05-01

    The ectoparasitic Monogenea comprise a major part of the obligate parasitic flatworm diversity. Although genomic adaptations to parasitism have been studied in the endoparasitic tapeworms (Cestoda) and flukes (Trematoda), no representative of the Monogenea has been investigated yet. We present the high-quality draft genome of Gyrodactylus salaris, an economically important monogenean ectoparasite of wild Atlantic salmon (Salmo salar). A total of 15,488 gene models were identified, of which 7,102 were functionally annotated. The controversial phylogenetic relationships within the obligate parasitic Neodermata were resolved in a phylogenomic analysis using 1,719 gene models (alignment length of >500,000 amino acids) for a set of 16 metazoan taxa. The Monogenea were found basal to the Cestoda and Trematoda, which implies ectoparasitism being plesiomorphic within the Neodermata and strongly supports a common origin of complex life cycles. Comparative analysis of seven parasitic flatworm genomes identified shared genomic features for the ecto- and endoparasitic lineages, such as a substantial reduction of the core bilaterian gene complement, including the homeodomain-containing genes, and a loss of the piwi and vasa genes, which are considered essential for animal development. Furthermore, the shared loss of functional fatty acid biosynthesis pathways and the absence of peroxisomes, the latter organelles presumed ubiquitous in eukaryotes except for parasitic protozoans, were inferred. The draft genome of G. salaris opens for future in-depth analyses of pathogenicity and host specificity of poorly characterized G. salaris strains, and will enhance studies addressing the genomics of host-parasite interactions and speciation in the highly diverse monogenean flatworms.

  4. The complete genome sequence and comparative genome analysis of the high pathogenicity Yersinia enterocolitica strain 8081.

    Directory of Open Access Journals (Sweden)

    Nicholas R Thomson

    2006-12-01

    Full Text Available The human enteropathogen, Yersinia enterocolitica, is a significant link in the range of Yersinia pathologies extending from mild gastroenteritis to bubonic plague. Comparison at the genomic level is a key step in our understanding of the genetic basis for this pathogenicity spectrum. Here we report the genome of Y. enterocolitica strain 8081 (serotype 0:8; biotype 1B and extensive microarray data relating to the genetic diversity of the Y. enterocolitica species. Our analysis reveals that the genome of Y. enterocolitica strain 8081 is a patchwork of horizontally acquired genetic loci, including a plasticity zone of 199 kb containing an extraordinarily high density of virulence genes. Microarray analysis has provided insights into species-specific Y. enterocolitica gene functions and the intraspecies differences between the high, low, and nonpathogenic Y. enterocolitica biotypes. Through comparative genome sequence analysis we provide new information on the evolution of the Yersinia. We identify numerous loci that represent ancestral clusters of genes potentially important in enteric survival and pathogenesis, which have been lost or are in the process of being lost, in the other sequenced Yersinia lineages. Our analysis also highlights large metabolic operons in Y. enterocolitica that are absent in the related enteropathogen, Yersinia pseudotuberculosis, indicating major differences in niche and nutrients used within the mammalian gut. These include clusters directing, the production of hydrogenases, tetrathionate respiration, cobalamin synthesis, and propanediol utilisation. Along with ancestral gene clusters, the genome of Y. enterocolitica has revealed species-specific and enteropathogen-specific loci. This has provided important insights into the pathology of this bacterium and, more broadly, into the evolution of the genus. Moreover, wider investigations looking at the patterns of gene loss and gain in the Yersinia have highlighted common

  5. Complete genome sequence of Enterococcus faecium strain TX16 and comparative genomic analysis of Enterococcus faecium genomes

    Directory of Open Access Journals (Sweden)

    Qin Xiang

    2012-07-01

    Full Text Available Abstract Background Enterococci are among the leading causes of hospital-acquired infections in the United States and Europe, with Enterococcus faecalis and Enterococcus faecium being the two most common species isolated from enterococcal infections. In the last decade, the proportion of enterococcal infections caused by E. faecium has steadily increased compared to other Enterococcus species. Although the underlying mechanism for the gradual replacement of E. faecalis by E. faecium in the hospital environment is not yet understood, many studies using genotyping and phylogenetic analysis have shown the emergence of a globally dispersed polyclonal subcluster of E. faecium strains in clinical environments. Systematic study of the molecular epidemiology and pathogenesis of E. faecium has been hindered by the lack of closed, complete E. faecium genomes that can be used as references. Results In this study, we report the complete genome sequence of the E. faecium strain TX16, also known as DO, which belongs to multilocus sequence type (ST 18, and was the first E. faecium strain ever sequenced. Whole genome comparison of the TX16 genome with 21 E. faecium draft genomes confirmed that most clinical, outbreak, and hospital-associated (HA strains (including STs 16, 17, 18, and 78, in addition to strains of non-hospital origin, group in the same clade (referred to as the HA clade and are evolutionally considerably more closely related to each other by phylogenetic and gene content similarity analyses than to isolates in the community-associated (CA clade with approximately a 3–4% average nucleotide sequence difference between the two clades at the core genome level. Our study also revealed that many genomic loci in the TX16 genome are unique to the HA clade. 380 ORFs in TX16 are HA-clade specific and antibiotic resistance genes are enriched in HA-clade strains. Mobile elements such as IS16 and transposons were also found almost exclusively in HA strains

  6. Comparative Genomic Analysis of Mannheimia haemolytica from Bovine Sources.

    Directory of Open Access Journals (Sweden)

    Cassidy L Klima

    Full Text Available Bovine respiratory disease is a common health problem in beef production. The primary bacterial agent involved, Mannheimia haemolytica, is a target for antimicrobial therapy and at risk for associated antimicrobial resistance development. The role of M. haemolytica in pathogenesis is linked to serotype with serotypes 1 (S1 and 6 (S6 isolated from pneumonic lesions and serotype 2 (S2 found in the upper respiratory tract of healthy animals. Here, we sequenced the genomes of 11 strains of M. haemolytica, representing all three serotypes and performed comparative genomics analysis to identify genetic features that may contribute to pathogenesis. Possible virulence associated genes were identified within 14 distinct prophage, including a periplasmic chaperone, a lipoprotein, peptidoglycan glycosyltransferase and a stress response protein. Prophage content ranged from 2-8 per genome, but was higher in S1 and S6 strains. A type I-C CRISPR-Cas system was identified in each strain with spacer diversity and organization conserved among serotypes. The majority of spacers occur in S1 and S6 strains and originate from phage suggesting that serotypes 1 and 6 may be more resistant to phage predation. However, two spacers complementary to the host chromosome targeting a UDP-N-acetylglucosamine 2-epimerase and a glycosyl transferases group 1 gene are present in S1 and S6 strains only indicating these serotypes may employ CRISPR-Cas to regulate gene expression to avoid host immune responses or enhance adhesion during infection. Integrative conjugative elements are present in nine of the eleven genomes. Three of these harbor extensive multi-drug resistance cassettes encoding resistance against the majority of drugs used to combat infection in beef cattle, including macrolides and tetracyclines used in human medicine. The findings here identify key features that are likely contributing to serotype related pathogenesis and specific targets for vaccine design

  7. Genomic Sequencing of Orientia tsutsugamushi Strain Karp, an Assembly Comparable to the Genome Size of the Strain Ikeda

    Science.gov (United States)

    Liao, Hsiao-Mei; Chao, Chien-Chung; Lei, Haiyan; Li, Bingjie; Tsai, Shien; Hung, Guo-Chiuan

    2016-01-01

    Orientia tsutsugamushi, an intracellular bacterium, belongs to the family Rickettsiaceae. This study presents the draft genome sequence of strain Karp, with 2.0 Mb as the size of the completed genome. This nearly finished draft genome sequence was annotated with the RAST server and the contents compared to those of the other strains. PMID:27540052

  8. Genomic Sequencing of Orientia tsutsugamushi Strain Karp, an Assembly Comparable to the Genome Size of the Strain Ikeda.

    Science.gov (United States)

    Liao, Hsiao-Mei; Chao, Chien-Chung; Lei, Haiyan; Li, Bingjie; Tsai, Shien; Hung, Guo-Chiuan; Ching, Wei-Mei; Lo, Shyh-Ching

    2016-08-18

    Orientia tsutsugamushi, an intracellular bacterium, belongs to the family Rickettsiaceae This study presents the draft genome sequence of strain Karp, with 2.0 Mb as the size of the completed genome. This nearly finished draft genome sequence was annotated with the RAST server and the contents compared to those of the other strains.

  9. Characterization of copy number variation in genomic regions containing STR loci using array comparative genomic hybridization.

    Science.gov (United States)

    Repnikova, Elena A; Rosenfeld, Jill A; Bailes, Andrea; Weber, Cecilia; Erdman, Linda; McKinney, Aimee; Ramsey, Sarah; Hashimoto, Sayaka; Lamb Thrush, Devon; Astbury, Caroline; Reshmi, Shalini C; Shaffer, Lisa G; Gastier-Foster, Julie M; Pyatt, Robert E

    2013-09-01

    Short tandem repeat (STR) loci are commonly used in forensic casework, familial analysis for human identification, and for monitoring hematopoietic cell engraftment after bone marrow transplant. Unexpected genetic variation leading to sequence and length differences in STR loci can complicate STR typing, and presents challenges in casework interpretation. Copy number variation (CNV) is a relatively recently identified form of genetic variation consisting of genomic regions present at variable copy numbers within an individual compared to a reference genome. Large scale population studies have demonstrated that likely all individuals carry multiple regions with CNV of 1kb in size or greater in their genome. To date, no study correlating genomic regions containing STR loci with CNV has been conducted. In this study, we analyzed results from 32,850 samples sent for clinical array comparative genomic hybridization (CGH) analysis for the presence of CNV at regions containing the 13 CODIS (Combined DNA Index System) STR, and the Amelogenin X (AMELX) and Amelogenin Y (AMELY) loci. Thirty-two individuals with CNV involving STR loci on chromosomes 2, 4, 7, 11, 12, 13, 16, and 21, and twelve with CNV involving the AMELX/AMELY loci were identified. These results were correlated with data from publicly available databases housing information on CNV identified in normal populations and additional clinical cases. These collective results demonstrate the presence of CNV in regions containing 9 of the 13 CODIS STR and AMELX/Y loci. Further characterization of STR profiles within regions of CNV, additional cataloging of these variants in multiple populations, and contributing such examples to the public domain will provide valuable information for reliable use of these loci.

  10. Comparative analysis of whole genome structure of Streptococcus suis using whole genome PCR scanning

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    An outbreak associated with Streptococcus suis infection in humans emerged in Sichuan province, China in 2005. The outbreak is atypical for the apparent large number of human cases, high fatality rate and geographical spread. To determine whether the bacterium has changed, we compared both human and animal isolates from the Sichuan outbreak with those collected previously within China and in other countries using whole genome PCR scanning (WGPScaning) comparative sequencing of several known virulence factor genes and multilocus sequence typing (MLST) analysis. WGPScanning analysis showed that all primer pairs yielded PCR products of the expected sizes in all four strains tested. The nucleotide sequences of all the detected virulence factor genes are identical in the four strains and MLST results showed that the four isolates studied and reference strain all belonged to the ST1 com-plex. No new genetic changes were found in the genome structure of the isolates from this Sichuan outbreak.

  11. Comparative analysis of whole genome structure of Streptococcus suis using whole genome PCR scanning

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    An outbreak associated with Streptococcus suis infection in humans emerged in Sichuan province, China in 2005. The outbreak is atypical for the apparent large number of human cases, high fatality rate and geographical spread. To determine whether the bacterium has changed, we compared both human and animal isolates from the Sichuan outbreak with those collected previously within China and in other countries using whole genome PCR scanning (WGPScaning) comparative sequencing of several known virulence factor genes and multilocus sequence typing (MLST) analysis. WGPScanning analysis showed that all primer pairs yielded PCR products of the expected sizes in all four strains tested. The nucleotide sequences of all the detected virulence factor genes are identical in the four strains and MLST results showed that the four isolates studied and reference strain all belonged to the ST1 complex. No new genetic changes were found in the genome structure of the isolates from this Sichuan outbreak.

  12. Comparative analysis of genomic signal processing for microarray data clustering.

    Science.gov (United States)

    Istepanian, Robert S H; Sungoor, Ala; Nebel, Jean-Christophe

    2011-12-01

    Genomic signal processing is a new area of research that combines advanced digital signal processing methodologies for enhanced genetic data analysis. It has many promising applications in bioinformatics and next generation of healthcare systems, in particular, in the field of microarray data clustering. In this paper we present a comparative performance analysis of enhanced digital spectral analysis methods for robust clustering of gene expression across multiple microarray data samples. Three digital signal processing methods: linear predictive coding, wavelet decomposition, and fractal dimension are studied to provide a comparative evaluation of the clustering performance of these methods on several microarray datasets. The results of this study show that the fractal approach provides the best clustering accuracy compared to other digital signal processing and well known statistical methods.

  13. Comparative genomics of Mycoplasma: analysis of conserved essential genes and diversity of the pan-genome.

    Directory of Open Access Journals (Sweden)

    Wei Liu

    Full Text Available Mycoplasma, the smallest self-replicating organism with a minimal metabolism and little genomic redundancy, is expected to be a close approximation to the minimal set of genes needed to sustain bacterial life. This study employs comparative evolutionary analysis of twenty Mycoplasma genomes to gain an improved understanding of essential genes. By analyzing the core genome of mycoplasmas, we finally revealed the conserved essential genes set for mycoplasma survival. Further analysis showed that the core genome set has many characteristics in common with experimentally identified essential genes. Several key genes, which are related to DNA replication and repair and can be disrupted in transposon mutagenesis studies, may be critical for bacteria survival especially over long period natural selection. Phylogenomic reconstructions based on 3,355 homologous groups allowed robust estimation of phylogenetic relatedness among mycoplasma strains. To obtain deeper insight into the relative roles of molecular evolution in pathogen adaptation to their hosts, we also analyzed the positive selection pressures on particular sites and lineages. There appears to be an approximate correlation between the divergence of species and the level of positive selection detected in corresponding lineages.

  14. Comparative Genomics and Transcriptomic Analysis of Mycobacterium Kansasii

    KAUST Repository

    Alzahid, Yara

    2014-04-01

    The group of Mycobacteria is one of the most intensively studied bacterial taxa, as they cause the two historical and worldwide known diseases: leprosy and tuberculosis. Mycobacteria not identified as tuberculosis or leprosy complex, have been referred to by ‘environmental mycobacteria’ or ‘Nontuberculous mycobacteria (NTM). Mycobacterium kansasii (M. kansasii) is one of the most frequent NTM pathogens, as it causes pulmonary disease in immuno-competent patients and pulmonary, and disseminated disease in patients with various immuno-deficiencies. There have been five documented subtypes of this bacterium, by different molecular typing methods, showing that type I causes tuberculosis-like disease in healthy individuals, and type II in immune-compromised individuals. The remaining types are said to be environmental, thereby, not causing any diseases. The aim of this project was to conduct a comparative genomic study of M. kansasii types I-V and investigating the gene expression level of those types. From various comparative genomics analysis, provided genomics evidence on why M. kansasii type I is considered pathogenic, by focusing on three key elements that are involved in virulence of Mycobacteria: ESX secretion system, Phospholipase c (plcb) and Mammalian cell entry (Mce) operons. The results showed the lack of the espA operon in types II-V, which renders the ESX- 1 operon dysfunctional, as espA is one of the key factors that control this secretion system. However, gene expression analysis showed this operon to be deleted in types II, III and IV. Furthermore, plcB was found to be truncated in types III and IV. Analysis of Mce operons (1-4) show that mce-1 operon is duplicated, mce-2 is absent and mce-3 and mce-4 is present in one copy in M. kansasii types I-V. Gene expression profiles of type I-IV, showed that the secreted proteins of ESX-1 were slightly upregulated in types II-IV when compared to type I and the secreted forms of ESX-5 were highly down

  15. Comparative genomic characterization of citrus-associated Xylella fastidiosa strains

    Directory of Open Access Journals (Sweden)

    Nunes Luiz R

    2007-12-01

    Full Text Available Abstract Background The xylem-inhabiting bacterium Xylella fastidiosa (Xf is the causal agent of Pierce's disease (PD in vineyards and citrus variegated chlorosis (CVC in orange trees. Both of these economically-devastating diseases are caused by distinct strains of this complex group of microorganisms, which has motivated researchers to conduct extensive genomic sequencing projects with Xf strains. This sequence information, along with other molecular tools, have been used to estimate the evolutionary history of the group and provide clues to understand the capacity of Xf to infect different hosts, causing a variety of symptoms. Nonetheless, although significant amounts of information have been generated from Xf strains, a large proportion of these efforts has concentrated on the study of North American strains, limiting our understanding about the genomic composition of South American strains – which is particularly important for CVC-associated strains. Results This paper describes the first genome-wide comparison among South American Xf strains, involving 6 distinct citrus-associated bacteria. Comparative analyses performed through a microarray-based approach allowed identification and characterization of large mobile genetic elements that seem to be exclusive to South American strains. Moreover, a large-scale sequencing effort, based on Suppressive Subtraction Hybridization (SSH, identified 290 new ORFs, distributed in 135 Groups of Orthologous Elements, throughout the genomes of these bacteria. Conclusion Results from microarray-based comparisons provide further evidence concerning activity of horizontally transferred elements, reinforcing their importance as major mediators in the evolution of Xf. Moreover, the microarray-based genomic profiles showed similarity between Xf strains 9a5c and Fb7, which is unexpected, given the geographical and chronological differences associated with the isolation of these microorganisms. The newly

  16. Comparative genomic analysis of Vibrio parahaemolyticus: serotype conversion and virulence

    Directory of Open Access Journals (Sweden)

    Gil Ana I

    2011-06-01

    Full Text Available Abstract Background Vibrio parahaemolyticus is a common cause of foodborne disease. Beginning in 1996, a more virulent strain having serotype O3:K6 caused major outbreaks in India and other parts of the world, resulting in the emergence of a pandemic. Other serovariants of this strain emerged during its dissemination and together with the original O3:K6 were termed strains of the pandemic clone. Two genomes, one of this virulent strain and one pre-pandemic strain have been sequenced. We sequenced four additional genomes of V. parahaemolyticus in this study that were isolated from different geographical regions and time points. Comparative genomic analyses of six strains of V. parahaemolyticus isolated from Asia and Peru were performed in order to advance knowledge concerning the evolution of V. parahaemolyticus; specifically, the genetic changes contributing to serotype conversion and virulence. Two pre-pandemic strains and three pandemic strains, isolated from different geographical regions, were serotype O3:K6 and either toxin profiles (tdh+, trh- or (tdh-, trh+. The sixth pandemic strain sequenced in this study was serotype O4:K68. Results Genomic analyses revealed that the trh+ and tdh+ strains had different types of pathogenicity islands and mobile elements as well as major structural differences between the tdh pathogenicity islands of the pre-pandemic and pandemic strains. In addition, the results of single nucleotide polymorphism (SNP analysis showed that 94% of the SNPs between O3:K6 and O4:K68 pandemic isolates were within a 141 kb region surrounding the O- and K-antigen-encoding gene clusters. The "core" genes of V. parahaemolyticus were also compared to those of V. cholerae and V. vulnificus, in order to delineate differences between these three pathogenic species. Approximately one-half (49-59% of each species' core genes were conserved in all three species, and 14-24% of the core genes were species-specific and in different

  17. The aggregate site frequency spectrum for comparative population genomic inference.

    Science.gov (United States)

    Xue, Alexander T; Hickerson, Michael J

    2015-12-01

    Understanding how assemblages of species responded to past climate change is a central goal of comparative phylogeography and comparative population genomics, an endeavour that has increasing potential to integrate with community ecology. New sequencing technology now provides the potential to perform complex demographic inference at unprecedented resolution across assemblages of nonmodel species. To this end, we introduce the aggregate site frequency spectrum (aSFS), an expansion of the site frequency spectrum to use single nucleotide polymorphism (SNP) data sets collected from multiple, co-distributed species for assemblage-level demographic inference. We describe how the aSFS is constructed over an arbitrary number of independent population samples and then demonstrate how the aSFS can differentiate various multispecies demographic histories under a wide range of sampling configurations while allowing effective population sizes and expansion magnitudes to vary independently. We subsequently couple the aSFS with a hierarchical approximate Bayesian computation (hABC) framework to estimate degree of temporal synchronicity in expansion times across taxa, including an empirical demonstration with a data set consisting of five populations of the threespine stickleback (Gasterosteus aculeatus). Corroborating what is generally understood about the recent postglacial origins of these populations, the joint aSFS/hABC analysis strongly suggests that the stickleback data are most consistent with synchronous expansion after the Last Glacial Maximum (posterior probability = 0.99). The aSFS will have general application for multilevel statistical frameworks to test models involving assemblages and/or communities, and as large-scale SNP data from nonmodel species become routine, the aSFS expands the potential for powerful next-generation comparative population genomic inference.

  18. Comparative genomics of the dormancy regulons in mycobacteria.

    Science.gov (United States)

    Gerasimova, Anna; Kazakov, Alexey E; Arkin, Adam P; Dubchak, Inna; Gelfand, Mikhail S

    2011-07-01

    In response to stresses, Mycobacterium cells become dormant. This process is regulated by the DosR transcription factor. In Mycobacterium tuberculosis, the dormancy regulon is well characterized and contains the dosR gene itself and dosS and dosT genes encoding DosR kinases, nitroreductases (acg; Rv3131), diacylglycerol acyltransferase (DGAT) (Rv3130c), and many universal stress proteins (USPs). In this study, we apply comparative genomic analysis to characterize the DosR regulons in nine Mycobacterium genomes, Rhodococcus sp. RHA1, Nocardia farcinica, and Saccharopolyspora erythraea. The regulons are highly labile, containing eight core gene groups (regulators, kinases, USPs, DGATs, nitroreductases, ferredoxins, heat shock proteins, and the orthologs of the predicted kinase [Rv2004c] from M. tuberculosis) and 10 additional genes with more restricted taxonomic distribution that are mostly involved in anaerobic respiration. The largest regulon is observed in M. marinum and the smallest in M. abscessus. Analysis of large gene families encoding USPs, nitroreductases, and DGATs demonstrates a mosaic distribution of regulated and nonregulated members, suggesting frequent acquisition and loss of DosR-binding sites.

  19. Chromosomal imbalances revealed in primary rhabdomyosarcomas by comparative genomic hybridization

    Institute of Scientific and Technical Information of China (English)

    LI Qiao-xin; LIU Chun-xia; CHUN Cai-pu; QI Yan; CHANG Bin; LI Xin-xia; CHEN Yun-zhao; NONG Wei-xia; LI Hong-an; LI Feng

    2009-01-01

    Background Previous cytogenetic studies revealed aberrations varied among the throe subtypes of rhabdomyosarcoma. We profiled chromosomal imbalances in the different subtypes and investigated the relationships between clinical parameters and genomic aberrations.Methods Comparative genomic hybridization was used to investigate genomic imbalances in 25 cases of primary rhabdomyosarcomas and two rhabdomyosarcoma cell lines. Specimens were reviewed to determine histological type, pathological grading and clinical staging.Results Changes involving one or more regions of the genome were seen in all rhabdomyosarcomal patients. For rhabdomyosarcoma, DNA sequence gains were most frequently (>30%) seen in chromosomes 2p, 12q, 6p, 9q, 10q, 1p,2q, 6q, 8q, 15q and 18q; losses from 3p, 11p and 6p. In aggressive alveolar rhabdomyosarcoma, frequent gains were seen on chromosomes 12q, 2p, 6p, 2q, 4q, 10q and 15q; losses from 3p, 6p, 1q and 5q. For embryonic rhabdomyosarcoma, frequent gains were on 7p, 9q, 2p, 18q, 1p and 8q; losses only from 11p. Frequently gained chromosome arms of translocation associated with rhabdomyosarcoma were 12q, 2, 6, 10q, 4q and 15q; losses from 3p,6p and 5q. The frequently gained chromosome arms of nontranslocation associated with rhabdomyosarcoma were 2p,9q and 18q, while 11p and 14q were the frequently lost chromosome arms. Gains on chromosome 12q were significantly correlated with translocation type. Gains on chromosome 9q were significantly correlated with clinical staging. Conclusions Gains on chromosomes 2p, 12q, 6p, 9q, 10q, 1p, 2q, 6q, 8q, 15q and 18q and losses on chromosomes 3p, 11p and 6p may be related to rhabdomyosarcomal carcinogenesis. Furthermore, gains on chromosome 12q may be correlated with translocation and gains on chromosome 9q with the early stages of rhabdomyosarcoma.

  20. Establishing a framework for comparative analysis of genome sequences

    Energy Technology Data Exchange (ETDEWEB)

    Bansal, A.K.

    1995-06-01

    This paper describes a framework and a high-level language toolkit for comparative analysis of genome sequence alignment The framework integrates the information derived from multiple sequence alignment and phylogenetic tree (hypothetical tree of evolution) to derive new properties about sequences. Multiple sequence alignments are treated as an abstract data type. Abstract operations have been described to manipulate a multiple sequence alignment and to derive mutation related information from a phylogenetic tree by superimposing parsimonious analysis. The framework has been applied on protein alignments to derive constrained columns (in a multiple sequence alignment) that exhibit evolutionary pressure to preserve a common property in a column despite mutation. A Prolog toolkit based on the framework has been implemented and demonstrated on alignments containing 3000 sequences and 3904 columns.

  1. Evolutionary insights into scleractinian corals using comparative genomic hybridizations.

    KAUST Repository

    Aranda, Manuel

    2012-09-21

    Coral reefs belong to the most ecologically and economically important ecosystems on our planet. Yet, they are under steady decline worldwide due to rising sea surface temperatures, disease, and pollution. Understanding the molecular impact of these stressors on different coral species is imperative in order to predict how coral populations will respond to this continued disturbance. The use of molecular tools such as microarrays has provided deep insight into the molecular stress response of corals. Here, we have performed comparative genomic hybridizations (CGH) with different coral species to an Acropora palmata microarray platform containing 13,546 cDNA clones in order to identify potentially rapidly evolving genes and to determine the suitability of existing microarray platforms for use in gene expression studies (via heterologous hybridization).

  2. Evolution of electron transfer out of the cell: comparative genomics of six Geobacter genomes

    Directory of Open Access Journals (Sweden)

    Young Nelson D

    2010-01-01

    Full Text Available Abstract Background Geobacter species grow by transferring electrons out of the cell - either to Fe(III-oxides or to man-made substances like energy-harvesting electrodes. Study of Geobacter sulfurreducens has shown that TCA cycle enzymes, inner-membrane respiratory enzymes, and periplasmic and outer-membrane cytochromes are required. Here we present comparative analysis of six Geobacter genomes, including species from the clade that predominates in the subsurface. Conservation of proteins across the genomes was determined to better understand the evolution of Geobacter species and to create a metabolic model applicable to subsurface environments. Results The results showed that enzymes for acetate transport and oxidation, and for proton transport across the inner membrane were well conserved. An NADH dehydrogenase, the ATP synthase, and several TCA cycle enzymes were among the best conserved in the genomes. However, most of the cytochromes required for Fe(III-reduction were not, including many of the outer-membrane cytochromes. While conservation of cytochromes was poor, an abundance and diversity of cytochromes were found in every genome, with duplications apparent in several species. Conclusions These results indicate there is a common pathway for acetate oxidation and energy generation across the family and in the last common ancestor. They also suggest that while cytochromes are important for extracellular electron transport, the path of electrons across the periplasm and outer membrane is variable. This combination of abundant cytochromes with weak sequence conservation suggests they may not be specific terminal reductases, but rather may be important in their heme-bearing capacity, as sinks for electrons between the inner-membrane electron transport chain and the extracellular acceptor.

  3. Genome sequence of Cronobacter sakazakii BAA-894 and comparative genomic hybridization analysis with other Cronobacter species.

    Directory of Open Access Journals (Sweden)

    Eva Kucerova

    Full Text Available BACKGROUND: The genus Cronobacter (formerly called Enterobacter sakazakii is composed of five species; C. sakazakii, C. malonaticus, C. turicensis, C. muytjensii, and C. dublinensis. The genus includes opportunistic human pathogens, and the first three species have been associated with neonatal infections. The most severe diseases are caused in neonates and include fatal necrotizing enterocolitis and meningitis. The genetic basis of the diversity within the genus is unknown, and few virulence traits have been identified. METHODOLOGY/PRINCIPAL FINDINGS: We report here the first sequence of a member of this genus, C. sakazakii strain BAA-894. The genome of Cronobacter sakazakii strain BAA-894 comprises a 4.4 Mb chromosome (57% GC content and two plasmids; 31 kb (51% GC and 131 kb (56% GC. The genome was used to construct a 387,000 probe oligonucleotide tiling DNA microarray covering the whole genome. Comparative genomic hybridization (CGH was undertaken on five other C. sakazakii strains, and representatives of the four other Cronobacter species. Among 4,382 annotated genes inspected in this study, about 55% of genes were common to all C. sakazakii strains and 43% were common to all Cronobacter strains, with 10-17% absence of genes. CONCLUSIONS/SIGNIFICANCE: CGH highlighted 15 clusters of genes in C. sakazakii BAA-894 that were divergent or absent in more than half of the tested strains; six of these are of probable prophage origin. Putative virulence factors were identified in these prophage and in other variable regions. A number of genes unique to Cronobacter species associated with neonatal infections (C. sakazakii, C. malonaticus and C. turicensis were identified. These included a copper and silver resistance system known to be linked to invasion of the blood-brain barrier by neonatal meningitic strains of Escherichia coli. In addition, genes encoding for multidrug efflux pumps and adhesins were identified that were unique to C. sakazakii

  4. Comparative genomic hybridizations reveal absence of large Streptomyces coelicolor genomic islands in Streptomyces lividans

    Directory of Open Access Journals (Sweden)

    Sherman David H

    2007-07-01

    Full Text Available Abstract Background The genomes of Streptomyces coelicolor and Streptomyces lividans bear a considerable degree of synteny. While S. coelicolor is the model streptomycete for studying antibiotic synthesis and differentiation, S. lividans is almost exclusively considered as the preferred host, among actinomycetes, for cloning and expression of exogenous DNA. We used whole genome microarrays as a comparative genomics tool for identifying the subtle differences between these two chromosomes. Results We identified five large S. coelicolor genomic islands (larger than 25 kb and 18 smaller islets absent in S. lividans chromosome. Many of these regions show anomalous GC bias and codon usage patterns. Six of them are in close vicinity of tRNA genes while nine are flanked with near perfect repeat sequences indicating that these are probable recent evolutionary acquisitions into S. coelicolor. Embedded within these segments are at least four DNA methylases and two probable methyl-sensing restriction endonucleases. Comparison with S. coelicolor transcriptome and proteome data revealed that some of the missing genes are active during the course of growth and differentiation in S. coelicolor. In particular, a pair of methylmalonyl CoA mutase (mcm genes involved in polyketide precursor biosynthesis, an acyl-CoA dehydrogenase implicated in timing of actinorhodin synthesis and bldB, a developmentally significant regulator whose mutation causes complete abrogation of antibiotic synthesis belong to this category. Conclusion Our findings provide tangible hints for elucidating the genetic basis of important phenotypic differences between these two streptomycetes. Importantly, absence of certain genes in S. lividans identified here could potentially explain the relative ease of DNA transformations and the conditional lack of actinorhodin synthesis in S. lividans.

  5. Survey Sequencing and Comparative Analysis of the Elephant Shark (Callorhinchus milii) Genome

    Science.gov (United States)

    Venkatesh, Byrappa; Kirkness, Ewen F; Loh, Yong-Hwee; Halpern, Aaron L; Lee, Alison P; Johnson, Justin; Dandona, Nidhi; Viswanathan, Lakshmi D; Tay, Alice; Venter, J. Craig; Strausberg, Robert L; Brenner, Sydney

    2007-01-01

    Owing to their phylogenetic position, cartilaginous fishes (sharks, rays, skates, and chimaeras) provide a critical reference for our understanding of vertebrate genome evolution. The relatively small genome of the elephant shark, Callorhinchus milii, a chimaera, makes it an attractive model cartilaginous fish genome for whole-genome sequencing and comparative analysis. Here, the authors describe survey sequencing (1.4× coverage) and comparative analysis of the elephant shark genome, one of the first cartilaginous fish genomes to be sequenced to this depth. Repetitive sequences, represented mainly by a novel family of short interspersed element–like and long interspersed element–like sequences, account for about 28% of the elephant shark genome. Fragments of approximately 15,000 elephant shark genes reveal specific examples of genes that have been lost differentially during the evolution of tetrapod and teleost fish lineages. Interestingly, the degree of conserved synteny and conserved sequences between the human and elephant shark genomes are higher than that between human and teleost fish genomes. Elephant shark contains putative four Hox clusters indicating that, unlike teleost fish genomes, the elephant shark genome has not experienced an additional whole-genome duplication. These findings underscore the importance of the elephant shark as a critical reference vertebrate genome for comparative analysis of the human and other vertebrate genomes. This study also demonstrates that a survey-sequencing approach can be applied productively for comparative analysis of distantly related vertebrate genomes. PMID:17407382

  6. Evolutionary insights into scleractinian corals using comparative genomic hybridizations

    Directory of Open Access Journals (Sweden)

    Aranda Manuel

    2012-09-01

    Full Text Available Abstract Background Coral reefs belong to the most ecologically and economically important ecosystems on our planet. Yet, they are under steady decline worldwide due to rising sea surface temperatures, disease, and pollution. Understanding the molecular impact of these stressors on different coral species is imperative in order to predict how coral populations will respond to this continued disturbance. The use of molecular tools such as microarrays has provided deep insight into the molecular stress response of corals. Here, we have performed comparative genomic hybridizations (CGH with different coral species to an Acropora palmata microarray platform containing 13,546 cDNA clones in order to identify potentially rapidly evolving genes and to determine the suitability of existing microarray platforms for use in gene expression studies (via heterologous hybridization. Results Our results showed that the current microarray platform for A. palmata is able to provide biological relevant information for a wide variety of coral species covering both the complex clade as well the robust clade. Analysis of the fraction of highly diverged genes showed a significantly higher amount of genes without annotation corroborating previous findings that point towards a higher rate of divergence for taxonomically restricted genes. Among the genes with annotation, we found many mitochondrial genes to be highly diverged in M. faveolata when compared to A. palmata, while the majority of nuclear encoded genes maintained an average divergence rate. Conclusions The use of present microarray platforms for transcriptional analyses in different coral species will greatly enhance the understanding of the molecular basis of stress and health and highlight evolutionary differences between scleractinian coral species. On a genomic basis, we show that cDNA arrays can be used to identify patterns of divergence. Mitochondrion-encoded genes seem to have diverged faster than

  7. Abductive Inference using Array-Based Logic

    DEFF Research Database (Denmark)

    Frisvad, Jeppe Revall; Falster, Peter; Møller, Gert L.;

    The notion of abduction has found its usage within a wide variety of AI fields. Computing abductive solutions has, however, shown to be highly intractable in logic programming. To avoid this intractability we present a new approach to logicbased abduction; through the geometrical view of data...... employed in array-based logic we embrace abduction in a simple structural operation. We argue that a theory of abduction on this form allows for an implementation which, at runtime, can perform abductive inference quite efficiently on arbitrary rules of logic representing knowledge of finite domains....

  8. Automated comparative auditing of NCIT genomic roles using NCBI.

    Science.gov (United States)

    Cohen, Barry; Oren, Marc; Min, Hua; Perl, Yehoshua; Halper, Michael

    2008-12-01

    Biomedical research has identified many human genes and various knowledge about them. The National Cancer Institute Thesaurus (NCIT) represents such knowledge as concepts and roles (relationships). Due to the rapid advances in this field, it is to be expected that the NCIT's Gene hierarchy will contain role errors. A comparative methodology to audit the Gene hierarchy with the use of the National Center for Biotechnology Information's (NCBI's) Entrez Gene database is presented. The two knowledge sources are accessed via a pair of Web crawlers to ensure up-to-date data. Our algorithms then compare the knowledge gathered from each, identify discrepancies that represent probable errors, and suggest corrective actions. The primary focus is on two kinds of gene-roles: (1) the chromosomal locations of genes, and (2) the biological processes in which genes play a role. Regarding chromosomal locations, the discrepancies revealed are striking and systematic, suggesting a structurally common origin. In regard to the biological processes, difficulties arise because genes frequently play roles in multiple processes, and processes may have many designations (such as synonymous terms). Our algorithms make use of the roles defined in the NCIT Biological Process hierarchy to uncover many probable gene-role errors in the NCIT. These results show that automated comparative auditing is a promising technique that can identify a large number of probable errors and corrections for them in a terminological genomic knowledge repository, thus facilitating its overall maintenance.

  9. Comparative Genomic Analyses of the Human NPHP1 Locus Reveal Complex Genomic Architecture and Its Regional Evolution in Primates.

    Directory of Open Access Journals (Sweden)

    Bo Yuan

    2015-12-01

    Full Text Available Many loci in the human genome harbor complex genomic structures that can result in susceptibility to genomic rearrangements leading to various genomic disorders. Nephronophthisis 1 (NPHP1, MIM# 256100 is an autosomal recessive disorder that can be caused by defects of NPHP1; the gene maps within the human 2q13 region where low copy repeats (LCRs are abundant. Loss of function of NPHP1 is responsible for approximately 85% of the NPHP1 cases-about 80% of such individuals carry a large recurrent homozygous NPHP1 deletion that occurs via nonallelic homologous recombination (NAHR between two flanking directly oriented ~45 kb LCRs. Published data revealed a non-pathogenic inversion polymorphism involving the NPHP1 gene flanked by two inverted ~358 kb LCRs. Using optical mapping and array-comparative genomic hybridization, we identified three potential novel structural variant (SV haplotypes at the NPHP1 locus that may protect a haploid genome from the NPHP1 deletion. Inter-species comparative genomic analyses among primate genomes revealed massive genomic changes during evolution. The aggregated data suggest that dynamic genomic rearrangements occurred historically within the NPHP1 locus and generated SV haplotypes observed in the human population today, which may confer differential susceptibility to genomic instability and the NPHP1 deletion within a personal genome. Our study documents diverse SV haplotypes at a complex LCR-laden human genomic region. Comparative analyses provide a model for how this complex region arose during primate evolution, and studies among humans suggest that intra-species polymorphism may potentially modulate an individual's susceptibility to acquiring disease-associated alleles.

  10. Comparative genome research between maize and rice using genomic in situ hybridization

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Using the genomic DNAs of maize and rice as probes respectively,the homology of maize and rice genomes was assessed by genomic in situ hybridization. When rice genomic DNAs were hybridized to maize, all chromosomes displayed many multiple discrete regions, while each rice chromosome delineated a single consecutive chromosomal region after they were hybridized with maize genomic DNAs. The results indicate that the genomes of maize and rice share high homology, and confirm the proposal that maize and rice are diverged from a common ancestor.

  11. Genome Stability of Lyme Disease Spirochetes: Comparative Genomics of Borrelia burgdorferi Plasmids

    Energy Technology Data Exchange (ETDEWEB)

    Casjens S. R.; Dunn J.; Mongodin, E. F.; Qiu, W.-G.; Luft, B. J.; Schutzer, S. E.; Gilcrease, E. B.; Huang, W. M.; Vujadinovic, M.; Aron, J. K.; Vargas, L. C.; Freeman, S.; Radune, D.; Weidman, J. F.; Dimitrov, G. I.; Khouri, H. M.; Sosa, J. E.; Halpin, R. A.; Fraser, C. M.

    2012-03-14

    Lyme disease is the most common tick-borne human illness in North America. In order to understand the molecular pathogenesis, natural diversity, population structure and epizootic spread of the North American Lyme agent, Borrelia burgdorferi sensu stricto, a much better understanding of the natural diversity of its genome will be required. Towards this end we present a comparative analysis of the nucleotide sequences of the numerous plasmids of B. burgdorferi isolates B31, N40, JD1 and 297. These strains were chosen because they include the three most commonly studied laboratory strains, and because they represent different major genetic lineages and so are informative regarding the genetic diversity and evolution of this organism. A unique feature of Borrelia genomes is that they carry a large number of linear and circular plasmids, and this work shows that strains N40, JD1, 297 and B31 carry related but non-identical sets of 16, 20, 19 and 21 plasmids, respectively, that comprise 33-40% of their genomes. We deduce that there are at least 28 plasmid compatibility types among the four strains. The B. burgdorferi {approx}900 Kbp linear chromosomes are evolutionarily exceptionally stable, except for a short {le}20 Kbp plasmid-like section at the right end. A few of the plasmids, including the linear lp54 and circular cp26, are also very stable. We show here that the other plasmids, especially the linear ones, are considerably more variable. Nearly all of the linear plasmids have undergone one or more substantial inter-plasmid rearrangements since their last common ancestor. In spite of these rearrangements and differences in plasmid contents, the overall gene complement of the different isolates has remained relatively constant.

  12. Genome stability of Lyme disease spirochetes: comparative genomics of Borrelia burgdorferi plasmids.

    Directory of Open Access Journals (Sweden)

    Sherwood R Casjens

    Full Text Available Lyme disease is the most common tick-borne human illness in North America. In order to understand the molecular pathogenesis, natural diversity, population structure and epizootic spread of the North American Lyme agent, Borrelia burgdorferi sensu stricto, a much better understanding of the natural diversity of its genome will be required. Towards this end we present a comparative analysis of the nucleotide sequences of the numerous plasmids of B. burgdorferi isolates B31, N40, JD1 and 297. These strains were chosen because they include the three most commonly studied laboratory strains, and because they represent different major genetic lineages and so are informative regarding the genetic diversity and evolution of this organism. A unique feature of Borrelia genomes is that they carry a large number of linear and circular plasmids, and this work shows that strains N40, JD1, 297 and B31 carry related but non-identical sets of 16, 20, 19 and 21 plasmids, respectively, that comprise 33-40% of their genomes. We deduce that there are at least 28 plasmid compatibility types among the four strains. The B. burgdorferi ∼900 Kbp linear chromosomes are evolutionarily exceptionally stable, except for a short ≤20 Kbp plasmid-like section at the right end. A few of the plasmids, including the linear lp54 and circular cp26, are also very stable. We show here that the other plasmids, especially the linear ones, are considerably more variable. Nearly all of the linear plasmids have undergone one or more substantial inter-plasmid rearrangements since their last common ancestor. In spite of these rearrangements and differences in plasmid contents, the overall gene complement of the different isolates has remained relatively constant.

  13. Comparative genomics of the relationship between gene structure and expression

    NARCIS (Netherlands)

    Ren, X.

    2006-01-01

    The relationship between the structure of genes and their expression is a relatively new aspect of genome organization and regulation. With more genome sequences and expression data becoming available, bioinformatics approaches can help the further elucidation of the relationships between gene struc

  14. Comparative Genomic Analysis of Meningitis- and Bacteremia-Causing Pneumococci Identifies a Common Core Genome.

    Science.gov (United States)

    Kulohoma, Benard W; Cornick, Jennifer E; Chaguza, Chrispin; Yalcin, Feyruz; Harris, Simon R; Gray, Katherine J; Kiran, Anmol M; Molyneux, Elizabeth; French, Neil; Parkhill, Julian; Faragher, Brian E; Everett, Dean B; Bentley, Stephen D; Heyderman, Robert S

    2015-10-01

    Streptococcus pneumoniae is a nasopharyngeal commensal that occasionally invades normally sterile sites to cause bloodstream infection and meningitis. Although the pneumococcal population structure and evolutionary genetics are well defined, it is not clear whether pneumococci that cause meningitis are genetically distinct from those that do not. Here, we used whole-genome sequencing of 140 isolates of S. pneumoniae recovered from bloodstream infection (n = 70) and meningitis (n = 70) to compare their genetic contents. By fitting a double-exponential decaying-function model, we show that these isolates share a core of 1,427 genes (95% confidence interval [CI], 1,425 to 1,435 genes) and that there is no difference in the core genome or accessory gene content from these disease manifestations. Gene presence/absence alone therefore does not explain the virulence behavior of pneumococci that reach the meninges. Our analysis, however, supports the requirement of a range of previously described virulence factors and vaccine candidates for both meningitis- and bacteremia-causing pneumococci. This high-resolution view suggests that, despite considerable competency for genetic exchange, all pneumococci are under considerable pressure to retain key components advantageous for colonization and transmission and that these components are essential for access to and survival in sterile sites.

  15. The Aspergillus Genome Database, a curated comparative genomics resource for gene, protein and sequence information for the Aspergillus research community.

    Science.gov (United States)

    Arnaud, Martha B; Chibucos, Marcus C; Costanzo, Maria C; Crabtree, Jonathan; Inglis, Diane O; Lotia, Adil; Orvis, Joshua; Shah, Prachi; Skrzypek, Marek S; Binkley, Gail; Miyasato, Stuart R; Wortman, Jennifer R; Sherlock, Gavin

    2010-01-01

    The Aspergillus Genome Database (AspGD) is an online genomics resource for researchers studying the genetics and molecular biology of the Aspergilli. AspGD combines high-quality manual curation of the experimental scientific literature examining the genetics and molecular biology of Aspergilli, cutting-edge comparative genomics approaches to iteratively refine and improve structural gene annotations across multiple Aspergillus species, and web-based research tools for accessing and exploring the data. All of these data are freely available at http://www.aspgd.org. We welcome feedback from users and the research community at aspergillus-curator@genome.stanford.edu.

  16. Serological evaluation of Mycobacterium ulcerans antigens identified by comparative genomics.

    Directory of Open Access Journals (Sweden)

    Sacha J Pidot

    Full Text Available A specific and sensitive serodiagnostic test for Mycobacterium ulcerans infection would greatly assist the diagnosis of Buruli ulcer and would also facilitate seroepidemiological surveys. By comparative genomics, we identified 45 potential M. ulcerans specific proteins, of which we were able to express and purify 33 in E. coli. Sera from 30 confirmed Buruli ulcer patients, 24 healthy controls from the same endemic region and 30 healthy controls from a non-endemic region in Benin were screened for antibody responses to these specific proteins by ELISA. Serum IgG responses of Buruli ulcer patients were highly variable, however, seven proteins (MUP045, MUP057, MUL_0513, Hsp65, and the polyketide synthase domains ER, AT propionate, and KR A showed a significant difference between patient and non-endemic control antibody responses. However, when sera from the healthy control subjects living in the same Buruli ulcer endemic area as the patients were examined, none of the proteins were able to discriminate between these two groups. Nevertheless, six of the seven proteins showed an ability to distinguish people living in an endemic area from those in a non-endemic area with an average sensitivity of 69% and specificity of 88%, suggesting exposure to M. ulcerans. Further validation of these six proteins is now underway to assess their suitability for use in Buruli ulcer seroepidemiological studies. Such studies are urgently needed to assist efforts to uncover environmental reservoirs and understand transmission pathways of the M. ulcerans.

  17. Comparative genomics of Geobacter chemotaxis genes reveals diverse signaling function

    Directory of Open Access Journals (Sweden)

    Antommattei Frances M

    2008-10-01

    Full Text Available Abstract Background Geobacter species are δ-Proteobacteria and are often the predominant species in a variety of sedimentary environments where Fe(III reduction is important. Their ability to remediate contaminated environments and produce electricity makes them attractive for further study. Cell motility, biofilm formation, and type IV pili all appear important for the growth of Geobacter in changing environments and for electricity production. Recent studies in other bacteria have demonstrated that signaling pathways homologous to the paradigm established for Escherichia coli chemotaxis can regulate type IV pili-dependent motility, the synthesis of flagella and type IV pili, the production of extracellular matrix material, and biofilm formation. The classification of these pathways by comparative genomics improves the ability to understand how Geobacter thrives in natural environments and better their use in microbial fuel cells. Results The genomes of G. sulfurreducens, G. metallireducens, and G. uraniireducens contain multiple (~70 homologs of chemotaxis genes arranged in several major clusters (six, seven, and seven, respectively. Unlike the single gene cluster of E. coli, the Geobacter clusters are not all located near the flagellar genes. The probable functions of some Geobacter clusters are assignable by homology to known pathways; others appear to be unique to the Geobacter sp. and contain genes of unknown function. We identified large numbers of methyl-accepting chemotaxis protein (MCP homologs that have diverse sensing domain architectures and generate a potential for sensing a great variety of environmental signals. We discuss mechanisms for class-specific segregation of the MCPs in the cell membrane, which serve to maintain pathway specificity and diminish crosstalk. Finally, the regulation of gene expression in Geobacter differs from E. coli. The sequences of predicted promoter elements suggest that the alternative sigma factors

  18. New genomic resources for switchgrass: a BAC library and comparative analysis of homoeologous genomic regions harboring bioenergy traits

    Directory of Open Access Journals (Sweden)

    Feltus Frank A

    2011-07-01

    Full Text Available Abstract Background Switchgrass, a C4 species and a warm-season grass native to the prairies of North America, has been targeted for development into an herbaceous biomass fuel crop. Genetic improvement of switchgrass feedstock traits through marker-assisted breeding and biotechnology approaches calls for genomic tools development. Establishment of integrated physical and genetic maps for switchgrass will accelerate mapping of value added traits useful to breeding programs and to isolate important target genes using map based cloning. The reported polyploidy series in switchgrass ranges from diploid (2X = 18 to duodecaploid (12X = 108. Like in other large, repeat-rich plant genomes, this genomic complexity will hinder whole genome sequencing efforts. An extensive physical map providing enough information to resolve the homoeologous genomes would provide the necessary framework for accurate assembly of the switchgrass genome. Results A switchgrass BAC library constructed by partial digestion of nuclear DNA with EcoRI contains 147,456 clones covering the effective genome approximately 10 times based on a genome size of 3.2 Gigabases (~1.6 Gb effective. Restriction digestion and PFGE analysis of 234 randomly chosen BACs indicated that 95% of the clones contained inserts, ranging from 60 to 180 kb with an average of 120 kb. Comparative sequence analysis of two homoeologous genomic regions harboring orthologs of the rice OsBRI1 locus, a low-copy gene encoding a putative protein kinase and associated with biomass, revealed that orthologous clones from homoeologous chromosomes can be unambiguously distinguished from each other and correctly assembled to respective fingerprint contigs. Thus, the data obtained not only provide genomic resources for further analysis of switchgrass genome, but also improve efforts for an accurate genome sequencing strategy. Conclusions The construction of the first switchgrass BAC library and comparative analysis of

  19. A reference pan-genome approach to comparative bacterial genomics: identification of novel epidemiological markers in pathogenic Campylobacter.

    Directory of Open Access Journals (Sweden)

    Guillaume Méric

    Full Text Available The increasing availability of hundreds of whole bacterial genomes provides opportunities for enhanced understanding of the genes and alleles responsible for clinically important phenotypes and how they evolved. However, it is a significant challenge to develop easy-to-use and scalable methods for characterizing these large and complex data and relating it to disease epidemiology. Existing approaches typically focus on either homologous sequence variation in genes that are shared by all isolates, or non-homologous sequence variation--focusing on genes that are differentially present in the population. Here we present a comparative genomics approach that simultaneously approximates core and accessory genome variation in pathogen populations and apply it to pathogenic species in the genus Campylobacter. A total of 7 published Campylobacter jejuni and Campylobacter coli genomes were selected to represent diversity across these species, and a list of all loci that were present at least once was compiled. After filtering duplicates a 7-isolate reference pan-genome, of 3,933 loci, was defined. A core genome of 1,035 genes was ubiquitous in the sample accounting for 59% of the genes in each isolate (average genome size of 1.68 Mb. The accessory genome contained 2,792 genes. A Campylobacter population sample of 192 genomes was screened for the presence of reference pan-genome loci with gene presence defined as a BLAST match of ≥ 70% identity over ≥ 50% of the locus length--aligned using MUSCLE on a gene-by-gene basis. A total of 21 genes were present only in C. coli and 27 only in C. jejuni, providing information about functional differences associated with species and novel epidemiological markers for population genomic analyses. Homologs of these genes were found in several of the genomes used to define the pan-genome and, therefore, would not have been identified using a single reference strain approach.

  20. In silico comparative genomic analysis of GABAA receptor transcriptional regulation

    Directory of Open Access Journals (Sweden)

    Joyce Christopher J

    2007-06-01

    Full Text Available Abstract Background Subtypes of the GABAA receptor subunit exhibit diverse temporal and spatial expression patterns. In silico comparative analysis was used to predict transcriptional regulatory features in individual mammalian GABAA receptor subunit genes, and to identify potential transcriptional regulatory components involved in the coordinate regulation of the GABAA receptor gene clusters. Results Previously unreported putative promoters were identified for the β2, γ1, γ3, ε, θ and π subunit genes. Putative core elements and proximal transcriptional factors were identified within these predicted promoters, and within the experimentally determined promoters of other subunit genes. Conserved intergenic regions of sequence in the mammalian GABAA receptor gene cluster comprising the α1, β2, γ2 and α6 subunits were identified as potential long range transcriptional regulatory components involved in the coordinate regulation of these genes. A region of predicted DNase I hypersensitive sites within the cluster may contain transcriptional regulatory features coordinating gene expression. A novel model is proposed for the coordinate control of the gene cluster and parallel expression of the α1 and β2 subunits, based upon the selective action of putative Scaffold/Matrix Attachment Regions (S/MARs. Conclusion The putative regulatory features identified by genomic analysis of GABAA receptor genes were substantiated by cross-species comparative analysis and now require experimental verification. The proposed model for the coordinate regulation of genes in the cluster accounts for the head-to-head orientation and parallel expression of the α1 and β2 subunit genes, and for the disruption of transcription caused by insertion of a neomycin gene in the close vicinity of the α6 gene, which is proximal to a putative critical S/MAR.

  1. Functional and Comparative Genomics of Lignocellulose Degradation by Schizophyllum commune

    Energy Technology Data Exchange (ETDEWEB)

    Ohm, Robin A.; Lee, Hanbyul; Park, Hongjae; Brewer, Heather M.; Carver, Akiko; Copeland, Alex; Grimwood, Jane; Lindquist, Erika; Lipzen, Anna; Martin, Joel; Purvine, Samuel O.; Schackwitz, Wendy; Tegelaar, Martin; Tritt, Andrew; Baker, Scott; Choi, In-Geol; Lugones, Luis G.; Wosten, Han A. B.; Grigoriev, Igor V.

    2014-03-14

    The Basidiomycete fungus Schizophyllum commune is a wood-decaying fungus and is used as a model system to study lignocellulose degradation. Version 3.0 of the genome assembly filled 269 of 316 sequence gaps and added 680 kb of sequence. This new assembly was reannotated using RNAseq transcriptomics data, and this resulted in 3110 (24percent) more genes. Two additional S. commune strains with different wood-decaying properties were sequenced, from Tattone (France) and Loenen (The Netherlands). Sequence comparison shows remarkably high sequence diversity between the strains. The overall SNP rate of > 100 SNPs/kb is among the highest rates of within-species polymorphisms in Basidiomycetes. Some well-described proteins like hydrophobins and transcription factors have less than 70percent sequence identity among the strains. Some chromosomes are better conserved than others and in some cases large parts of chromosomes are missing from one or more strains. Gene expression on glucose, cellulose and wood was analyzed in two S. commune strains. Overall, gene expression correlated between the two strains, but there were some notable exceptions. Of particular interest are CAZymes (carbohydrate-active enzymes) that are regulated in different ways in the different strains. In both strains the transcription factor Fsp1 was strongly up-regulated during growth on cellulose and wood, when compared to glucose. Over-expression of Fsp1 using a constitutive promoter resulted in higher cellulose and xylose-degrading enzyme activity, which suggests that Fsp1 is involved in regulating CAZyme gene expression. Two CAZyme genes (of family GH61 and GH11) were shown to be strongly up-regulated during growth on cellulose, compared to glucose. Proteomics on the secreted proteins in the growth medium confirmed this. A promoter analysis revealed the shortest active promoters for these two genes, as well as putative transcription factor binding sites.

  2. DeltaProt: a software toolbox for comparative genomics

    Directory of Open Access Journals (Sweden)

    Willassen Nils P

    2010-11-01

    Full Text Available Abstract Background Statistical bioinformatics is the study of biological data sets obtained by new micro-technologies by means of proper statistical methods. For a better understanding of environmental adaptations of proteins, orthologous sequences from different habitats may be explored and compared. The main goal of the DeltaProt Toolbox is to provide users with important functionality that is needed for comparative screening and studies of extremophile proteins and protein classes. Visualization of the data sets is also the focus of this article, since visualizations can play a key role in making the various relationships transparent. This application paper is intended to inform the reader of the existence, functionality, and applicability of the toolbox. Results We present the DeltaProt Toolbox, a software toolbox that may be useful in importing, analyzing and visualizing data from multiple alignments of proteins. The toolbox has been written in MATLAB™ to provide an easy and user-friendly platform, including a graphical user interface, while ensuring good numerical performance. Problems in genome biology may be easily stated thanks to a compact input format. The toolbox also offers the possibility of utilizing structural information from the SABLE or other structure predictors. Different sequence plots can then be viewed and compared in order to find their similarities and differences. Detailed statistics are also calculated during the procedure. Conclusions The DeltaProt package is open source and freely available for academic, non-commercial use. The latest version of DeltaProt can be obtained from http://services.cbu.uib.no/software/deltaprot/. The website also contains documentation, and the toolbox comes with real data sets that are intended for training in applying the models to carry out bioinformatical and statistical analyses of protein sequences. Equipped with the new algorithms proposed here, DeltaProt serves as an auxiliary

  3. Comparative analysis of genome maintenance genes in naked mole rat, mouse, and human

    NARCIS (Netherlands)

    S.L. Macrae (Sheila L.); Q. Zhang (Quanwei); C. Lemetre (Christophe); I. Seim (Inge); R.B. Calder (Robert B.); J.H.J. Hoeijmakers (Jan); Y. Suh (Yousin); V.N. Gladyshev (Vadim N.); A. Seluanov (Andrei); V. Gorbunova (Vera); J. Vijg (Jan); Z.D. Zhang (Zhengdong D.)

    2015-01-01

    textabstractGenome maintenance (GM) is an essential defense system against aging and cancer, as both are characterized by increased genome instability. Here, we compared the copy number variation and mutation rate of 518 GM-associated genes in the naked mole rat (NMR), mouse, and human genomes. GM g

  4. Comparative genomic analysis of Lactobacillus rhamnosus GG reveals pili containing a human- mucus binding protein

    NARCIS (Netherlands)

    Kankainen, M.; Paulin, L.; Tynkkynen, S.; Ossowski, von I.; Reunanen, J.; Partanen, P.; Satokari, A.; Vesterlund, S.; Hendrickx, A.P.; Lebeer, S.; Keersmaecker, de S.C.; Vanderleyden, J.; Hämäläinen, T.; Laukkanen, S.; Salovuori, N.; Ritari, J.; Alatalo, E.; Korpela, R.; Mattila-Sandholm, T.; Lassig, A.; Hatakka, K.; Kinnunen, K.T.; Karjalainen, H.; Saxelin, M.; Laakso, K.; Surakka, A.; Palva, A.; Salusjärvi, T.; Auvinen, P.; Vos, de W.M.

    2009-01-01

    To unravel the biological function of the widely used probiotic bacterium Lactobacillus rhamnosus GG, we compared its 3.0-Mbp genome sequence with the similarly sized genome of L. rhamnosus LC705, an adjunct starter culture exhibiting reduced binding to mucus. Both genomes demonstrated high sequence

  5. Approaches for Comparative Genomics in Aspergillus and Penicillium

    DEFF Research Database (Denmark)

    Rasmussen, Jane Lind Nybo; Theobald, Sebastian; Brandl, Julian;

    2016-01-01

    The number of available genomes in the closely related fungal genera Aspergillus and Penicillium is rapidly increasing. At the time of writing, the genomes of 62 species are available, and an even higher number is being prepared. Fungal comparative genomics is thus becoming steadily more powerful...

  6. Microbial comparative pan-genomics using binomial mixture models

    DEFF Research Database (Denmark)

    Ussery, David; Snipen, L; Almøy, T

    2009-01-01

    The size of the core- and pan-genome of bacterial species is a topic of increasing interest due to the growing number of sequenced prokaryote genomes, many from the same species. Attempts to estimate these quantities have been made, using regression methods or mixture models. We extend the latter...... approach by using statistical ideas developed for capture-recapture problems in ecology and epidemiology. RESULTS: We estimate core- and pan-genome sizes for 16 different bacterial species. The results reveal a complex dependency structure for most species, manifested as heterogeneous detection...... probabilities. Estimated pan-genome sizes range from small (around 2600 gene families) in Buchnera aphidicola to large (around 43000 gene families) in Escherichia coli. Results for Echerichia coli show that as more data become available, a larger diversity is estimated, indicating an extensive pool of rarely...

  7. Metagenome Skimming of Insect Specimen Pools: Potential for Comparative Genomics.

    Science.gov (United States)

    Linard, Benjamin; Crampton-Platt, Alex; Gillett, Conrad P D T; Timmermans, Martijn J T N; Vogler, Alfried P

    2015-05-14

    Metagenomic analyses are challenging in metazoans, but high-copy number and repeat regions can be assembled from low-coverage sequencing by "genome skimming," which is applied here as a new way of characterizing metagenomes obtained in an ecological or taxonomic context. Illumina shotgun sequencing on two pools of Coleoptera (beetles) of approximately 200 species each were assembled into tens of thousands of scaffolds. Repeated low-coverage sequencing recovered similar scaffold sets consistently, although approximately 70% of scaffolds could not be identified against existing genome databases. Identifiable scaffolds included mitochondrial DNA, conserved sequences with hits to expressed sequence tag and protein databases, and known repeat elements of high and low complexity, including numerous copies of rRNA and histone genes. Assemblies of histones captured a diversity of gene order and primary sequence in Coleoptera. Scaffolds with similarity to multiple sites in available coleopteran genome sequences for Dendroctonus and Tribolium revealed high specificity of scaffolds to either of these genomes, in particular for high-copy number repeats. Numerous "clusters" of scaffolds mapped to the same genomic site revealed intra- and/or intergenomic variation within a metagenome pool. In addition to effect of taxonomic composition of the metagenomes, the number of mapped scaffolds also revealed structural differences between the two reference genomes, although the significance of this striking finding remains unclear. Finally, apparently exogenous sequences were recovered, including potential food plants, fungal pathogens, and bacterial symbionts. The "metagenome skimming" approach is useful for capturing the genomic diversity of poorly studied, species-rich lineages and opens new prospects in environmental genomics.

  8. Microbial comparative pan-genomics using binomial mixture models

    Directory of Open Access Journals (Sweden)

    Ussery David W

    2009-08-01

    Full Text Available Abstract Background The size of the core- and pan-genome of bacterial species is a topic of increasing interest due to the growing number of sequenced prokaryote genomes, many from the same species. Attempts to estimate these quantities have been made, using regression methods or mixture models. We extend the latter approach by using statistical ideas developed for capture-recapture problems in ecology and epidemiology. Results We estimate core- and pan-genome sizes for 16 different bacterial species. The results reveal a complex dependency structure for most species, manifested as heterogeneous detection probabilities. Estimated pan-genome sizes range from small (around 2600 gene families in Buchnera aphidicola to large (around 43000 gene families in Escherichia coli. Results for Echerichia coli show that as more data become available, a larger diversity is estimated, indicating an extensive pool of rarely occurring genes in the population. Conclusion Analyzing pan-genomics data with binomial mixture models is a way to handle dependencies between genomes, which we find is always present. A bottleneck in the estimation procedure is the annotation of rarely occurring genes.

  9. e-Fungi: a data resource for comparative analysis of fungal genomes

    Directory of Open Access Journals (Sweden)

    Hubbard Simon J

    2007-11-01

    Full Text Available Abstract Background The number of sequenced fungal genomes is ever increasing, with about 200 genomes already fully sequenced or in progress. Only a small percentage of those genomes have been comprehensively studied, for example using techniques from functional genomics. Comparative analysis has proven to be a useful strategy for enhancing our understanding of evolutionary biology and of the less well understood genomes. However, the data required for these analyses tends to be distributed in various heterogeneous data sources, making systematic comparative studies a cumbersome task. Furthermore, comparative analyses benefit from close integration of derived data sets that cluster genes or organisms in a way that eases the expression of requests that clarify points of similarity or difference between species. Description To support systematic comparative analyses of fungal genomes we have developed the e-Fungi database, which integrates a variety of data for more than 30 fungal genomes. Publicly available genome data, functional annotations, and pathway information has been integrated into a single data repository and complemented with results of comparative analyses, such as MCL and OrthoMCL cluster analysis, and predictions of signaling proteins and the sub-cellular localisation of proteins. To access the data, a library of analysis tasks is available through a web interface. The analysis tasks are motivated by recent comparative genomics studies, and aim to support the study of evolutionary biology as well as community efforts for improving the annotation of genomes. Web services for each query are also available, enabling the tasks to be incorporated into workflows. Conclusion The e-Fungi database provides fungal biologists with a resource for comparative studies of a large range of fungal genomes. Its analysis library supports the comparative study of genome data, functional annotation, and results of large scale analyses over all the

  10. Complete genome sequences and comparative genome analysis of Lactobacillus plantarum strain 5-2 isolated from fermented soybean.

    Science.gov (United States)

    Liu, Chen-Jian; Wang, Rui; Gong, Fu-Ming; Liu, Xiao-Feng; Zheng, Hua-Jun; Luo, Yi-Yong; Li, Xiao-Ran

    2015-12-01

    Lactobacillus plantarum is an important probiotic and is mostly isolated from fermented foods. We sequenced the genome of L. plantarum strain 5-2, which was derived from fermented soybean isolated from Yunnan province, China. The strain was determined to contain 3114 genes. Fourteen complete insertion sequence (IS) elements were found in 5-2 chromosome. There were 24 DNA replication proteins and 76 DNA repair proteins in the 5-2 genome. Consistent with the classification of L. plantarum as a facultative heterofermentative lactobacillus, the 5-2 genome encodes key enzymes required for the EMP (Embden-Meyerhof-Parnas) and phosphoketolase (PK) pathways. Several components of the secretion machinery are found in the 5-2 genome, which was compared with L. plantarum ST-III, JDM1 and WCFS1. Most of the specific proteins in the four genomes appeared to be related to their prophage elements.

  11. Natural Product Biosynthetic Diversity and Comparative Genomics of the Cyanobacteria.

    Science.gov (United States)

    Dittmann, Elke; Gugger, Muriel; Sivonen, Kaarina; Fewer, David P

    2015-10-01

    Cyanobacteria are an ancient lineage of slow-growing photosynthetic bacteria and a prolific source of natural products with intricate chemical structures and potent biological activities. The bulk of these natural products are known from just a handful of genera. Recent efforts have elucidated the mechanisms underpinning the biosynthesis of a diverse array of natural products from cyanobacteria. Many of the biosynthetic mechanisms are unique to cyanobacteria or rarely described from other organisms. Advances in genome sequence technology have precipitated a deluge of genome sequences for cyanobacteria. This makes it possible to link known natural products to biosynthetic gene clusters but also accelerates the discovery of new natural products through genome mining. These studies demonstrate that cyanobacteria encode a huge variety of cryptic gene clusters for the production of natural products, and the known chemical diversity is likely to be just a fraction of the true biosynthetic capabilities of this fascinating and ancient group of organisms.

  12. Comparative genomics of Vibrio cholerae from Haiti, Asia, and Africa.

    Science.gov (United States)

    Reimer, Aleisha R; Van Domselaar, Gary; Stroika, Steven; Walker, Matthew; Kent, Heather; Tarr, Cheryl; Talkington, Deborah; Rowe, Lori; Olsen-Rasmussen, Melissa; Frace, Michael; Sammons, Scott; Dahourou, Georges Anicet; Boncy, Jacques; Smith, Anthony M; Mabon, Philip; Petkau, Aaron; Graham, Morag; Gilmour, Matthew W; Gerner-Smidt, Peter

    2011-11-01

    Cholera was absent from the island of Hispaniola at least a century before an outbreak that began in Haiti in the fall of 2010. Pulsed-field gel electrophoresis (PFGE) analysis of clinical isolates from the Haiti outbreak and recent global travelers returning to the United States showed indistinguishable PFGE fingerprints. To better explore the genetic ancestry of the Haiti outbreak strain, we acquired 23 whole-genome Vibrio cholerae sequences: 9 isolates obtained in Haiti or the Dominican Republic, 12 PFGE pattern-matched isolates linked to Asia or Africa, and 2 nonmatched outliers from the Western Hemisphere. Phylogenies for whole-genome sequences and core genome single-nucleotide polymorphisms showed that the Haiti outbreak strain is genetically related to strains originating in India and Cameroon. However, because no identical genetic match was found among sequenced contemporary isolates, a definitive genetic origin for the outbreak in Haiti remains speculative.

  13. IMG 4 version of the integrated microbial genomes comparative analysis system

    Energy Technology Data Exchange (ETDEWEB)

    Markowitz, Victor M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Chen, I-Min A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Palaniappan, Krishna [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Chu, Ken [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Szeto, Ernest [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Pillay, Manoj [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Ratner, Anna [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Huang, Jinghua [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Data Management and Technology Center. Computational Research Division; Woyke, Tanja [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Huntemann, Marcel [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Anderson, Iain [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Billis, Konstantinos [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Varghese, Neha [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Mavromatis, Konstantinos [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Pati, Amrita [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Ivanova, Natalia N. [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program; Kyrpides, Nikos C. [USDOE Joint Genome Institute (JGI), Walnut Creek, CA (United States). Microbial Genome and Metagenome Program

    2013-10-27

    The Integrated Microbial Genomes (IMG) data warehouse integrates genomes from all three domains of life, as well as plasmids, viruses and genome fragments. IMG provides tools for analyzing and reviewing the structural and functional annotations of genomes in a comparative context. IMG’s data content and analytical capabilities have increased continuously since its first version released in 2005. Since the last report published in the 2012 NAR Database Issue, IMG’s annotation and data integration pipelines have evolved while new tools have been added for recording and analyzing single cell genomes, RNA Seq and biosynthetic cluster data. Finally, different IMG datamarts provide support for the analysis of publicly available genomes (IMG/W: http://img.jgi.doe.gov/w), expert review of genome annotations (IMG/ER: http://img.jgi.doe.gov/er) and teaching and training in the area of microbial genome analysis (IMG/EDU: http://img.jgi.doe.gov/edu).

  14. IMG 4 version of the integrated microbial genomes comparative analysis system.

    Science.gov (United States)

    Markowitz, Victor M; Chen, I-Min A; Palaniappan, Krishna; Chu, Ken; Szeto, Ernest; Pillay, Manoj; Ratner, Anna; Huang, Jinghua; Woyke, Tanja; Huntemann, Marcel; Anderson, Iain; Billis, Konstantinos; Varghese, Neha; Mavromatis, Konstantinos; Pati, Amrita; Ivanova, Natalia N; Kyrpides, Nikos C

    2014-01-01

    The Integrated Microbial Genomes (IMG) data warehouse integrates genomes from all three domains of life, as well as plasmids, viruses and genome fragments. IMG provides tools for analyzing and reviewing the structural and functional annotations of genomes in a comparative context. IMG's data content and analytical capabilities have increased continuously since its first version released in 2005. Since the last report published in the 2012 NAR Database Issue, IMG's annotation and data integration pipelines have evolved while new tools have been added for recording and analyzing single cell genomes, RNA Seq and biosynthetic cluster data. Different IMG datamarts provide support for the analysis of publicly available genomes (IMG/W: http://img.jgi.doe.gov/w), expert review of genome annotations (IMG/ER: http://img.jgi.doe.gov/er) and teaching and training in the area of microbial genome analysis (IMG/EDU: http://img.jgi.doe.gov/edu).

  15. Comparative genomics in cyprinids: Common carp EST's help the annotation of the zebrafish genome

    NARCIS (Netherlands)

    Christoffels, A.; Bartfai, R.; Srinivasan, H.; Komen, J.

    2006-01-01

    Background - Automatic annotation of sequenced eukaryotic genomes integrates a combination of methodologies such as ab-initio methods and alignment of homologous genes and/or proteins. For example, annotation of the zebrafish genome within Ensembl relies heavily on available cDNA and protein sequenc

  16. Complete genome sequence and comparative genomic analysis of an emerging human pathogen, serotype V Streptococcus agalactiae

    NARCIS (Netherlands)

    Tettelin, H; Masignani, [No Value; Cieslewicz, MJ; Eisen, JA; Peterson, S; Paulsen, IT; Nelson, KE; Margarit, [No Value; Read, TD; Madoff, LC; Beanan, MJ; Brinkac, LM; Daugherty, SC; DeBoy, RT; Durkin, AS; Kolonay, JF; Madupu, R; Lewis, MR; Radune, D; Fedorova, NB; Scanlan, D; Khouri, H; Mulligan, S; Carty, HA; Cline, RT; Van Aken, SE; Gill, J; Scarselli, M; Mora, M; Iacobini, ET; Brettoni, C; Galli, G; Mariani, M; Vegni, F; Maione, D; Rinaudo, D; Rappuoli, R; Telford, JL; Kasper, DL; Grandi, G; Fraser, CM

    2002-01-01

    The 2,160,267 bp genome sequence of Streptococcus agalactiae, the leading cause of bacterial sepsis, pneumonia, and meningitis in neonates in the U.S. and Europe, is predicted to encode 2,175 genes. Genome comparisons among S. agalactiae, Streptococcus pneumoniae, Streptococcus pyogenes, and the oth

  17. Comparative and functional genomics of lipases in holometabolous insects.

    Science.gov (United States)

    Horne, Irene; Haritos, Victoria S; Oakeshott, John G

    2009-08-01

    Lipases have key roles in insect lipid acquisition, storage and mobilisation and are also fundamental to many physiological processes underpinning insect reproduction, development, defence from pathogens and oxidative stress, and pheromone signalling. We have screened the recently sequenced genomes of five species from four orders of holometabolous insects, the dipterans Drosophila melanogaster and Anopheles gambiae, the hymenopteran Apis mellifera, the moth Bombyx mori and the beetle Tribolium castaneum, for the six major lipase families that are also found in other organisms. The two most numerous families in the insects, the neutral and acid lipases, are also the main families in mammals, albeit not in Caenorhabditis elegans, plants or microbes. Total numbers of the lipases vary two-fold across the five insect species, from numbers similar to those in mammals up to numbers comparable to those seen in C. elegans. Whilst there is a high degree of orthology with mammalian lipases in the other four families, the great majority of the insect neutral and acid lipases have arisen since the insect orders themselves diverged. Intriguingly, about 10% of the insect neutral and acid lipases have lost motifs critical for catalytic function. Examination of the length of lid and loop regions of the neutral lipase sequences suggest that most of the insect lipases lack triacylglycerol (TAG) hydrolysis activity, although the acid lipases all have intact cap domains required for TAG hydrolysis. We have also reviewed the sequence databases and scientific literature for insights into the expression profiles and functions of the insect neutral and acid lipases and the orthologues of the mammalian adipose triglyceride lipase which has a pivotal role in lipid mobilisation. These data suggest that some of the acid and neutral lipase diversity may be due to a requirement for rapid accumulation of dietary lipids. The different roles required of lipases at the four discrete life stages of

  18. Genome sequence and comparative analysis of Avibacterium paragallinarum

    Science.gov (United States)

    Requena, David; Chumbe, Ana; Torres, Michael; Alzamora, Ofelia; Ramirez, Manuel; Valdivia-Olarte, Hugo; Gutierrez, Andres Hazaet; Izquierdo-Lara, Ray; Saravia, Luis Enrique; Zavaleta, Milagros; Tataje-Lavanda, Luis; Best, Ivan; Fernández-Sánchez, Manolo; Icochea, Eliana; Zimic, Mirko; Fernández-Díaz, Manolo

    2013-01-01

    Background: Avibacterium paragallinarum, the causative agent of infectious coryza, is a highly contagious respiratory acute disease of poultry, which affects commercial chickens, laying hens and broilers worldwide. Methodology: In this study, we performed the whole genome sequencing, assembly and annotation of a Peruvian isolate of A. paragallinarum. Genome was sequenced in a 454 GS FLX Titanium system. De novo assembly was performed and annotation was completed with GS De Novo Assembler 2.6 using the H. influenzae str. F3031 gene model. Manual curation of the genome was performed with Artemis. Putative function of genes was predicted with Blast2GO. Virulence factors were identified by comparison with the Virulence Factor Database. Results: The genome obtained has a length of 2.47 Mb with 40.66% of GC content. Seventy five large contigs (>500 nt) were obtained, which comprised 1,204 predicted genes. All the contigs are available in Genbank [GenBank: PRJNA64665]. A total of 103 virulence factors, reported in the Virulence Factor Database, were found in A. paragallinarum. Forty four of them are present in 7 species of Haemophilus, which are related with pathogenesis, virulence and host immune system evasion. A tetracycline-resistance associated transposon (Tn10), was found in A. paragallinarum, possibly acting as a defense mechanism. Discussion and conclusion: The availability of A. paragallinarum genome represents an important source of information for the development of diagnostic tests, genotyping, and novel antigens for potential vaccines against infectious coryza. Identification of virulence factors contributes to better understanding the pathogenesis, and planning efforts for prevention and control of the disease. PMID:23861570

  19. Genome sequences and comparative genomics of two Lactobacillus ruminis strains from the bovine and human intestinal tracts

    LENUS (Irish Health Repository)

    2011-08-30

    Abstract Background The genus Lactobacillus is characterized by an extraordinary degree of phenotypic and genotypic diversity, which recent genomic analyses have further highlighted. However, the choice of species for sequencing has been non-random and unequal in distribution, with only a single representative genome from the L. salivarius clade available to date. Furthermore, there is no data to facilitate a functional genomic analysis of motility in the lactobacilli, a trait that is restricted to the L. salivarius clade. Results The 2.06 Mb genome of the bovine isolate Lactobacillus ruminis ATCC 27782 comprises a single circular chromosome, and has a G+C content of 44.4%. In silico analysis identified 1901 coding sequences, including genes for a pediocin-like bacteriocin, a single large exopolysaccharide-related cluster, two sortase enzymes, two CRISPR loci and numerous IS elements and pseudogenes. A cluster of genes related to a putative pilin was identified, and shown to be transcribed in vitro. A high quality draft assembly of the genome of a second L. ruminis strain, ATCC 25644 isolated from humans, suggested a slightly larger genome of 2.138 Mb, that exhibited a high degree of synteny with the ATCC 27782 genome. In contrast, comparative analysis of L. ruminis and L. salivarius identified a lack of long-range synteny between these closely related species. Comparison of the L. salivarius clade core proteins with those of nine other Lactobacillus species distributed across 4 major phylogenetic groups identified the set of shared proteins, and proteins unique to each group. Conclusions The genome of L. ruminis provides a comparative tool for directing functional analyses of other members of the L. salivarius clade, and it increases understanding of the divergence of this distinct Lactobacillus lineage from other commensal lactobacilli. The genome sequence provides a definitive resource to facilitate investigation of the genetics, biochemistry and host

  20. Comparative genomics of the Staphylococcus intermedius group of animal pathogens

    Directory of Open Access Journals (Sweden)

    Nouri eBen Zakour

    2012-04-01

    Full Text Available The Staphylococcus intermedius group consists of 3 closely-related coagulase-positive bacterial species including S. intermedius, Staphylococus pseudintermedius, and Staphylococcus delphini. S. pseudintermedius is a major skin pathogen of dogs, which occasionally causes severe zoonotic infections of humans. S. delphini has been isolated from an array of different animals including horses, mink and pigeons, whereas S. intermedius has been isolated only from pigeons to date. Here we provide a detailed analysis of the S. pseudintermedius whole genome sequence in comparison to high quality draft S. intermedius and S. delphini genomes, and to other sequenced staphylococcal species. The core genome of the SIG was highly conserved with average nucleotide identity (ANI between the 3 species of 93.61%, which is very close to the threshold of species delineation (95% ANI, highlighting the close-relatedness of the SIG species. However, considerable variation was identified in the content of mobile genetic elements, cell wall-associated proteins, and iron and sugar transporters, reflecting the distinct ecological niches inhabited. Of note, S. pseudintermedius ED99 contained a Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR locus of the Nmeni subtype and S. intermedius contained both Nmeni and Mtube subtypes. In contrast to S. intermedius and S. delphini and most other staphylococci examined to date, S. pseudintermedius contained at least 9 predicted reverse transcriptase (RT Group II introns. Furthermore, S. pseudintermedius ED99 encoded several transposons which were largely responsible for its multi-resistant phenotype. Overall, the study highlights extensive differences in accessory genome content between closely-related staphylococcal species inhabiting distinct host niches, providing new avenues for research into pathogenesis and bacterial host-adaptation.

  1. Comparative Genomic Analysis of Human Fungal Pathogens Causing Paracoccidioidomycosis

    OpenAIRE

    Desjardins, Christopher A; Champion, Mia D.; Holder, Jason W.; Muszewska, Anna; Goldberg, Jonathan; Bailao, Alexandre M.; Brigido, Marcelo de Macedo; Silva Ferreira, Marcia Eliana da; Garcia, Ana Maria; Grynberg, Marcin; Gujja, Sharvari; Heiman, David I.; Henn, Matthew R.; Kodira, Chinnappa D.; Leon-Narvaez, Henry

    2011-01-01

    Paracoccidioides is a fungal pathogen and the cause of paracoccidioidomycosis, a health-threatening human systemic mycosis endemic to Latin America. Infection by Paracoccidioides, a dimorphic fungus in the order Onygenales, is coupled with a thermally regulated transition from a soil-dwelling filamentous form to a yeast-like pathogenic form. To better understand the genetic basis of growth and pathogenicity in Paracoccidioides, we sequenced the genomes of two strains of Paracoccidioides brasi...

  2. The surprising diversity of clostridial hydrogenases: a comparative genomic perspective

    OpenAIRE

    Calusinska, Magdalena; Happe, Thomas; Joris, Bernard; Wilmotte, Annick

    2010-01-01

    Among the large variety of micro-organisms capable of fermentative hydrogen production, strict anaerobes such as members of the genus Clostridium are the most widely studied. They can produce hydrogen by a reversible reduction of protons accumulated during fermentation to dihydrogen, a reaction which is catalysed by hydrogenases. Sequenced genomes provide completely new insights into the diversity of clostridial hydrogenases. Building on previous reports, we found that [FeFe] hydrogenases are...

  3. Comparative analysis of whole-genome sequences of Streptococcus suis

    Institute of Scientific and Technical Information of China (English)

    LI Pengli; WEI Wu; LI Yixue; MA Yuanyuan; DING Guohui; LI Xiaoping; WANG Xiaojing; ZHANG Liwen; SUN Jingchun; WANG Yong; TU Kang; WANG Ningning; HAO Pei; WANG Chuan; CAO Zhiwei; SHI Tieliu

    2006-01-01

    The outbreak of Streptococcus suis recently in some districts of Sichuan Province in China has caused over 30 deaths and over 200 infections in human beings. In order to study the pathogenicity mechanism and to prevent the bacteria from spreading and infecting human beings and swine, we have annotated and analyzed the genomes of two strains, Streptococcus suis P1/7 and 89-1591 respectively. The whole length of P1/7 is 2.007 Mb,and has 1969 ORFs. In contrast, the partial genome sequence of 89-1591 is 1.98 Mb in length and exists in 177 contigs with 1918 ORFs. Analysis shows that the average lengths of CDSs in two genomes are very close, and the numbers of the homolog ORFs are 1306 between those two strains. Most of the toxicity factors of the two strains are homologeous, but there are still some significant differences between those two strains. For example, among the 11 genes (cps2A-cps2K) encoding for the capsules in P1/7, 4(cps2A, 2B, 2I, 2J) are not detected in strain 89-1591.At the same time, the genes encoding EF and Haemolysin in P1/7 are also not found in strain 89-1591. Besides, the genes related to DNA replication, repair and recombination differ from each other significantly and there also exist certain differences among the surface proteins. Those characteristics indicate that those two strains have evolved their own specific functions to adapt to the different environments and that the pathogenesis of the two strains is different. We have accumulated comprehensive genomics information for future systematic studies of S.sui. Our results are helpful for disease prevention,vaccine development, as well as drug design for S.suis.

  4. Comparative genomics in chicken and Pekin duck using FISH mapping and microarray analysis

    Directory of Open Access Journals (Sweden)

    Fowler Katie E

    2009-08-01

    Full Text Available Abstract Background The availability of the complete chicken (Gallus gallus genome sequence as well as a large number of chicken probes for fluorescent in-situ hybridization (FISH and microarray resources facilitate comparative genomic studies between chicken and other bird species. In a previous study, we provided a comprehensive cytogenetic map for the turkey (Meleagris gallopavo and the first analysis of copy number variants (CNVs in birds. Here, we extend this approach to the Pekin duck (Anas platyrhynchos, an obvious target for comparative genomic studies due to its agricultural importance and resistance to avian flu. Results We provide a detailed molecular cytogenetic map of the duck genome through FISH assignment of 155 chicken clones. We identified one inter- and six intrachromosomal rearrangements between chicken and duck macrochromosomes and demonstrated conserved synteny among all microchromosomes analysed. Array comparative genomic hybridisation revealed 32 CNVs, of which 5 overlap previously designated "hotspot" regions between chicken and turkey. Conclusion Our results suggest extensive conservation of avian genomes across 90 million years of evolution in both macro- and microchromosomes. The data on CNVs between chicken and duck extends previous analyses in chicken and turkey and supports the hypotheses that avian genomes contain fewer CNVs than mammalian genomes and that genomes of evolutionarily distant species share regions of copy number variation ("CNV hotspots". Our results will expedite duck genomics, assist marker development and highlight areas of interest for future evolutionary and functional studies.

  5. Complete genome sequence of the fire blight pathogen Erwinia pyrifoliae DSM 12163T and comparative genomic insights into plant pathogenicity

    Directory of Open Access Journals (Sweden)

    Frey Jürg E

    2010-01-01

    Full Text Available Abstract Background Erwinia pyrifoliae is a newly described necrotrophic pathogen, which causes fire blight on Asian (Nashi pear and is geographically restricted to Eastern Asia. Relatively little is known about its genetics compared to the closely related main fire blight pathogen E. amylovora. Results The genome of the type strain of E. pyrifoliae strain DSM 12163T, was sequenced using both 454 and Solexa pyrosequencing and annotated. The genome contains a circular chromosome of 4.026 Mb and four small plasmids. Based on their respective role in virulence in E. amylovora or related organisms, we identified several putative virulence factors, including type III and type VI secretion systems and their effectors, flagellar genes, sorbitol metabolism, iron uptake determinants, and quorum-sensing components. A deletion in the rpoS gene covering the most conserved region of the protein was identified which may contribute to the difference in virulence/host-range compared to E. amylovora. Comparative genomics with the pome fruit epiphyte Erwinia tasmaniensis Et1/99 showed that both species are overall highly similar, although specific differences were identified, for example the presence of some phage gene-containing regions and a high number of putative genomic islands containing transposases in the E. pyrifoliae DSM 12163T genome. Conclusions The E. pyrifoliae genome is an important addition to the published genome of E. tasmaniensis and the unfinished genome of E. amylovora providing a foundation for re-sequencing additional strains that may shed light on the evolution of the host-range and virulence/pathogenicity of this important group of plant-associated bacteria.

  6. Clinical array-based karyotyping of breast cancer with equivocal HER2 status resolves gene copy number and reveals chromosome 17 complexity

    Directory of Open Access Journals (Sweden)

    Zadeh Soheila

    2010-07-01

    Full Text Available Abstract Background HER2 gene copy status, and concomitant administration of trastuzumab (Herceptin, remains one of the best examples of targeted cancer therapy based on understanding the genomic etiology of disease. However, newly diagnosed breast cancer cases with equivocal HER2 results present a challenge for the oncologist who must make treatment decisions despite the patient's unresolved HER2 status. In some cases both immunohistochemistry (IHC and fluorescence in situ hybridization (FISH are reported as equivocal, whereas in other cases IHC results and FISH are discordant for positive versus negative results. The recent validation of array-based, molecular karyotyping for clinical oncology testing provides an alternative method for determination of HER2 gene copy number status in cases remaining unresolved by traditional methods. Methods In the current study, DNA extracted from 20 formalin fixed paraffin embedded (FFPE tissue samples from newly diagnosed cases of invasive ductal carcinoma referred to our laboratory with unresolved HER2 status, were analyzed using a clinically validated genomic array containing 127 probes covering the HER2 amplicon, the pericentromeric regions, and both chromosome 17 arms. Results Array-based comparative genomic hybridization (array CGH analysis of chromosome 17 resolved HER2 gene status in [20/20] (100% of cases and revealed additional chromosome 17 copy number changes in [18/20] (90% of cases. Array CGH analysis also revealed two false positives and one false negative by FISH due to "ratio skewing" caused by chromosomal gains and losses in the centromeric region. All cases with complex rearrangements of chromosome 17 showed genome-wide chromosomal instability. Conclusions These results illustrate the analytical power of array-based genomic analysis as a clinical laboratory technique for resolution of HER2 status in breast cancer cases with equivocal results. The frequency of complex chromosome 17

  7. Mitochondrial genome sequences and comparative genomics ofPhytophthora ramorum and P. sojae

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Frank N.; Douda, Bensasson; Tyler, Brett M.; Boore,Jeffrey L.

    2007-01-01

    The complete sequences of the mitochondrial genomes of theoomycetes of Phytophthora ramorum and P. sojae were determined during thecourse of their complete nuclear genome sequencing (Tyler, et al. 2006).Both are circular, with sizes of 39,314 bp for P. ramorum and 42,975 bpfor P. sojae. Each contains a total of 37 identifiable protein-encodinggenes, 25 or 26 tRNAs (P. sojae and P. ramorum, respectively)specifying19 amino acids, and a variable number of ORFs (7 for P. ramorum and 12for P. sojae) which are potentially additional functional genes.Non-coding regions comprise approximately 11.5 percent and 18.4 percentof the genomes of P. ramorum and P. sojae, respectively. Relative to P.sojae, there is an inverted repeat of 1,150 bp in P. ramorum thatincludes an unassigned unique ORF, a tRNA gene, and adjacent non-codingsequences, but otherwise the gene order in both species is identical.Comparisons of these genomes with published sequences of the P. infestansmitochondrial genome reveals a number of similarities, but the gene orderin P. infestans differs in two adjacent locations due to inversions.Sequence alignments of the three genomes indicated sequence conservationranging from 75 to 85 percent and that specific regions were morevariable than others.

  8. Leveraging Comparative Genomics to Identify and Functionally Characterize Genes Associated with Sperm Phenotypes in Python bivittatus (Burmese Python)

    OpenAIRE

    Kristopher J. L. Irizarry; Josep Rutllant

    2016-01-01

    Comparative genomics approaches provide a means of leveraging functional genomics information from a highly annotated model organism’s genome (such as the mouse genome) in order to make physiological inferences about the role of genes and proteins in a less characterized organism’s genome (such as the Burmese python). We employed a comparative genomics approach to produce the functional annotation of Python bivittatus genes encoding proteins associated with sperm phenotypes. We identify 129 g...

  9. Comparative Genomics Analysis of Streptomyces Species Reveals Their Adaptation to the Marine Environment and Their Diversity at the Genomic Level.

    Science.gov (United States)

    Tian, Xinpeng; Zhang, Zhewen; Yang, Tingting; Chen, Meili; Li, Jie; Chen, Fei; Yang, Jin; Li, Wenjie; Zhang, Bing; Zhang, Zhang; Wu, Jiayan; Zhang, Changsheng; Long, Lijuan; Xiao, Jingfa

    2016-01-01

    Over 200 genomes of streptomycete strains that were isolated from various environments are available from the NCBI. However, little is known about the characteristics that are linked to marine adaptation in marine-derived streptomycetes. The particularity and complexity of the marine environment suggest that marine streptomycetes are genetically diverse. Here, we sequenced nine strains from the Streptomyces genus that were isolated from different longitudes, latitudes, and depths of the South China Sea. Then we compared these strains to 22 NCBI downloaded streptomycete strains. Thirty-one streptomycete strains are clearly grouped into a marine-derived subgroup and multiple source subgroup-based phylogenetic tree. The phylogenetic analyses have revealed the dynamic process underlying streptomycete genome evolution, and lateral gene transfer is an important driving force during the process. Pan-genomics analyses have revealed that streptomycetes have an open pan-genome, which reflects the diversity of these streptomycetes and guarantees the species a quick and economical response to diverse environments. Functional and comparative genomics analyses indicate that the marine-derived streptomycetes subgroup possesses some common characteristics of marine adaptation. Our findings have expanded our knowledge of how ocean isolates of streptomycete strains adapt to marine environments. The availability of streptomycete genomes from the South China Sea will be beneficial for further analysis on marine streptomycetes and will enrich the South China Sea's genetic data sources.

  10. Comparative Genomics Analysis of Streptomyces Species Reveals Their Adaptation to the Marine Environment and Their Diversity at the Genomic Level

    Science.gov (United States)

    Tian, Xinpeng; Zhang, Zhewen; Yang, Tingting; Chen, Meili; Li, Jie; Chen, Fei; Yang, Jin; Li, Wenjie; Zhang, Bing; Zhang, Zhang; Wu, Jiayan; Zhang, Changsheng; Long, Lijuan; Xiao, Jingfa

    2016-01-01

    Over 200 genomes of streptomycete strains that were isolated from various environments are available from the NCBI. However, little is known about the characteristics that are linked to marine adaptation in marine-derived streptomycetes. The particularity and complexity of the marine environment suggest that marine streptomycetes are genetically diverse. Here, we sequenced nine strains from the Streptomyces genus that were isolated from different longitudes, latitudes, and depths of the South China Sea. Then we compared these strains to 22 NCBI downloaded streptomycete strains. Thirty-one streptomycete strains are clearly grouped into a marine-derived subgroup and multiple source subgroup-based phylogenetic tree. The phylogenetic analyses have revealed the dynamic process underlying streptomycete genome evolution, and lateral gene transfer is an important driving force during the process. Pan-genomics analyses have revealed that streptomycetes have an open pan-genome, which reflects the diversity of these streptomycetes and guarantees the species a quick and economical response to diverse environments. Functional and comparative genomics analyses indicate that the marine-derived streptomycetes subgroup possesses some common characteristics of marine adaptation. Our findings have expanded our knowledge of how ocean isolates of streptomycete strains adapt to marine environments. The availability of streptomycete genomes from the South China Sea will be beneficial for further analysis on marine streptomycetes and will enrich the South China Sea’s genetic data sources. PMID:27446038

  11. The Integrated Microbial Genomes (IMG) System: An Expanding Comparative Analysis Resource

    Energy Technology Data Exchange (ETDEWEB)

    Markowitz, Victor M.; Chen, I-Min A.; Palaniappan, Krishna; Chu, Ken; Szeto, Ernest; Grechkin, Yuri; Ratner, Anna; Anderson, Iain; Lykidis, Athanasios; Mavromatis, Konstantinos; Ivanova, Natalia N.; Kyrpides, Nikos C.

    2009-09-13

    The integrated microbial genomes (IMG) system serves as a community resource for comparative analysis of publicly available genomes in a comprehensive integrated context. IMG contains both draft and complete microbial genomes integrated with other publicly available genomes from all three domains of life, together with a large number of plasmids and viruses. IMG provides tools and viewers for analyzing and reviewing the annotations of genes and genomes in a comparative context. Since its first release in 2005, IMG's data content and analytical capabilities have been constantly expanded through regular releases. Several companion IMG systems have been set up in order to serve domain specific needs, such as expert review of genome annotations. IMG is available at .

  12. Complete genome sequence of Borrelia afzelii K78 and comparative genome analysis.

    Directory of Open Access Journals (Sweden)

    Wolfgang Schüler

    Full Text Available The main Borrelia species causing Lyme borreliosis in Europe and Asia are Borrelia afzelii, B. garinii, B. burgdorferi and B. bavariensis. This is in contrast to the United States, where infections are exclusively caused by B. burgdorferi. Until to date the genome sequences of four B. afzelii strains, of which only two include the numerous plasmids, are available. In order to further assess the genetic diversity of B. afzelii, the most common species in Europe, responsible for the large variety of clinical manifestations of Lyme borreliosis, we have determined the full genome sequence of the B. afzelii strain K78, a clinical isolate from Austria. The K78 genome contains a linear chromosome (905,949 bp and 13 plasmids (8 linear and 5 circular together presenting 1,309 open reading frames of which 496 are located on plasmids. With the exception of lp28-8, all linear replicons in their full length including their telomeres have been sequenced. The comparison with the genomes of the four other B. afzelii strains, ACA-1, PKo, HLJ01 and Tom3107, as well as the one of B. burgdorferi strain B31, confirmed a high degree of conservation within the linear chromosome of B. afzelii, whereas plasmid encoded genes showed a much larger diversity. Since some plasmids present in B. burgdorferi are missing in the B. afzelii genomes, the corresponding virulence factors of B. burgdorferi are found in B. afzelii on other unrelated plasmids. In addition, we have identified a species specific region in the circular plasmid, cp26, which could be used for species determination. Different non-coding RNAs have been located on the B. afzelii K78 genome, which have not previously been annotated in any of the published Borrelia genomes.

  13. Improving molecular diagnosis of aniridia and WAGR syndrome using customized targeted array-based CGH

    Science.gov (United States)

    Vallespín, Elena; Villaverde, Cristina; Martín-Arenas, Rubén; Vélez-Monsalve, Camilo; Lorda-Sánchez, Isabel; Nevado, Julián; Trujillo-Tiebas, María José; Lapunzina, Pablo; Ayuso, Carmen; Corton, Marta

    2017-01-01

    Chromosomal deletions at 11p13 are a frequent cause of congenital Aniridia, a rare pan-ocular genetic disease, and of WAGR syndrome, accounting up to 30% of cases. First-tier genetic testing for newborn with aniridia, to detect 11p13 rearrangements, includes Multiplex Ligation-dependent Probe Amplification (MLPA) and karyotyping. However, neither of these approaches allow obtaining a complete picture of the high complexity of chromosomal deletions and breakpoints in aniridia. Here, we report the development and validation of a customized targeted array-based comparative genomic hybridization, so called WAGR-array, for comprehensive high-resolution analysis of CNV in the WAGR locus. Our approach increased the detection rate in a Spanish cohort of 38 patients with aniridia, WAGR syndrome and other related ocular malformations, allowing to characterize four undiagnosed aniridia cases, and to confirm MLPA findings in four additional patients. For all patients, breakpoints were accurately established and a contiguous deletion syndrome, involving a large number of genes, was identified in three patients. Moreover, we identified novel microdeletions affecting 3' PAX6 regulatory regions in three families with isolated aniridia. This tool represents a good strategy for the genetic diagnosis of aniridia and associated syndromes, allowing for a more accurate CNVs detection, as well as a better delineation of breakpoints. Our results underline the clinical importance of performing exhaustive and accurate analysis of chromosomal rearrangements for patients with aniridia, especially newborns and those without defects in PAX6 after diagnostic screening. PMID:28231309

  14. Comparative Analysis of CpG Islands in Four Fish Genomes

    Directory of Open Access Journals (Sweden)

    Leng Han

    2008-01-01

    Full Text Available There has been much interest in CpG islands (CGIs, clusters of CpG dinucleotides in GC-rich regions, because they are considered gene markers and involved in gene regulation. To date, there has been no genome-wide analysis of CGIs in the fish genome. We first evaluated the performance of three popular CGI identification algorithms in four fish genomes (tetraodon, stickleback, medaka, and zebrafish. Our results suggest that Takai and Jones' (2002 algorithm is most suitable for comparative analysis of CGIs in the fish genome. Then, we performed a systematic analysis of CGIs in the four fish genomes using Takai and Jones' algorithm, compared to other vertebrate genomes. We found that both the number of CGIs and the CGI density vary greatly among these genomes. Remarkably, each fish genome presents a distinct distribution of CGI density with some genomic factors (e.g., chromosome size and chromosome GC content. These findings are helpful for understanding evolution of fish genomes and the features of fish CGIs.

  15. Progress in the detection of human genome structural variations

    Institute of Scientific and Technical Information of China (English)

    WU XueMei; XIAO HuaSheng

    2009-01-01

    The emerging of high.throughput and high-resolution genomic technologies led to the detection of submicroscopic variants ranging from 1 kb to 3 Mb in the human genome. These variants include copy number variations (CNVs), inversions, insertions, deletions and other complex rearrangements of DNA sequences. This paper briefly reviews the commonly used technologies to discover both genomic structural variants and their potential influences. Particularly, we highlight the array-based, PCR-based and sequencing-based assays, including array-based comparative genomic hybridization (aCGH),representational oligonucleotide microarray analysis (ROMA), multiplex amplifiable probe hybridization (MAPH), multiplex ligation-dependent probe amplification (MLPA), paired-end mapping (PEM), and next-generation DNA sequencing technologies. Furthermore, we discuss the limitations and challenges of current assays and give advices on how to make the database of genomic variations more reliable.

  16. Progress in the detection of human genome structural variations

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The emerging of high-throughput and high-resolution genomic technologies led to the detection of submicroscopic variants ranging from 1 kb to 3 Mb in the human genome.These variants include copy number variations(CNVs),inversions,insertions,deletions and other complex rearrangements of DNA sequences.This paper briefly reviews the commonly used technologies to discover both genomic structural variants and their potential influences.Particularly,we highlight the array-based,PCR-based and sequencing-based assays,including array-based comparative genomic hybridization(aCGH),representational oligonucleotide microarray analysis(ROMA),multiplex amplifiable probe hybridization(MAPH),multiplex ligation-dependent probe amplification(MLPA),paired-end mapping(PEM),and next-generation DNA sequencing technologies.Furthermore,we discuss the limitations and challenges of current assays and give advices on how to make the database of genomic variations more reliable.

  17. Comparative analysis of catfish BAC end sequences with the zebrafish genome

    Directory of Open Access Journals (Sweden)

    Abernathy Jason

    2009-12-01

    Full Text Available Abstract Background Comparative mapping is a powerful tool to transfer genomic information from sequenced genomes to closely related species for which whole genome sequence data are not yet available. However, such an approach is still very limited in catfish, the most important aquaculture species in the United States. This project was initiated to generate additional BAC end sequences and demonstrate their applications in comparative mapping in catfish. Results We reported the generation of 43,000 BAC end sequences and their applications for comparative genome analysis in catfish. Using these and the additional 20,000 existing BAC end sequences as a resource along with linkage mapping and existing physical map, conserved syntenic regions were identified between the catfish and zebrafish genomes. A total of 10,943 catfish BAC end sequences (17.3% had significant BLAST hits to the zebrafish genome (cutoff value ≤ e-5, of which 3,221 were unique gene hits, providing a platform for comparative mapping based on locations of these genes in catfish and zebrafish. Genetic linkage mapping of microsatellites associated with contigs allowed identification of large conserved genomic segments and construction of super scaffolds. Conclusion BAC end sequences and their associated polymorphic markers are great resources for comparative genome analysis in catfish. Highly conserved chromosomal regions were identified to exist between catfish and zebrafish. However, it appears that the level of conservation at local genomic regions are high while a high level of chromosomal shuffling and rearrangements exist between catfish and zebrafish genomes. Orthologous regions established through comparative analysis should facilitate both structural and functional genome analysis in catfish.

  18. Array comparative genomic hybridization of keratoacanthomas and squamous cell carcinomas

    DEFF Research Database (Denmark)

    Li, Jian; Wang, Kai; Gao, Fei

    2012-01-01

    Keratoacanthoma (KA) is a benign keratinocytic neoplasm that spontaneously regresses after 3-6 months and shares features with squamous cell carcinomas (SCCs). Furthermore, there are reports of KAs that have metastasized, invoking the question of whether KA is a variant of SCC (Hodak et al., 1993......). To date, no reported criteria are sensitive enough to discriminate reliably between KA and SCC, and consequently there is a clinical need for discriminating markers. Our previous study analyzed 132 KAs and 29 SCCs and revealed significantly different regions of genomic aberrations using chromosomal...

  19. Comparative and functional genomic analyses of the pathogenicity of phytopathogen Xanthomonas campestris pv. campestris

    OpenAIRE

    Qian, Wei; Jia, Yantao; Ren, Shuang-Xi; He, Yong-Qiang; Feng, Jia-Xun; Lu, Ling-Feng; Sun, Qihong; Ying, Ge; Tang, Dong-Jie; Tang, Hua; Wu, Wei; Hao, Pei; Wang, Lifeng; Jiang, Bo-Le; Zeng, Shenyan

    2005-01-01

    Xanthomonas campestris pathovar campestris (Xcc) is the causative agent of crucifer black rot disease, which causes severe losses in agricultural yield world-wide. This bacterium is a model organism for studying plant-bacteria interactions. We sequenced the complete genome of Xcc 8004 (5,148,708 bp), which is highly conserved relative to that of Xcc ATCC 33913. Comparative genomics analysis indicated that, in addition to a significant genomic-scale rearrangement cross the replication axis bet...

  20. Comparative Genomics of the Extreme Acidophile Acidithiobacillus thiooxidans Reveals Intraspecific Divergence and Niche Adaptation

    OpenAIRE

    Zhang, Xian; Feng, Xue; Tao, Jiemeng; Ma, Liyuan; Xiao, Yunhua; Liang, Yili; Liu, Xueduan; Yin, Huaqun

    2016-01-01

    Acidithiobacillus thiooxidans known for its ubiquity in diverse acidic and sulfur-bearing environments worldwide was used as the research subject in this study. To explore the genomic fluidity and intraspecific diversity of Acidithiobacillus thiooxidans (A. thiooxidans) species, comparative genomics based on nine draft genomes was performed. Phylogenomic scrutiny provided first insights into the multiple groupings of these strains, suggesting that genetic diversity might be potentially correl...

  1. Delineation of Steroid-Degrading Microorganisms through Comparative Genomic Analysis

    Directory of Open Access Journals (Sweden)

    Lee H. Bergstrand

    2016-03-01

    Full Text Available Steroids are ubiquitous in natural environments and are a significant growth substrate for microorganisms. Microbial steroid metabolism is also important for some pathogens and for biotechnical applications. This study delineated the distribution of aerobic steroid catabolism pathways among over 8,000 microorganisms whose genomes are available in the NCBI RefSeq database. Combined analysis of bacterial, archaeal, and fungal genomes with both hidden Markov models and reciprocal BLAST identified 265 putative steroid degraders within only Actinobacteria and Proteobacteria, which mainly originated from soil, eukaryotic host, and aquatic environments. These bacteria include members of 17 genera not previously known to contain steroid degraders. A pathway for cholesterol degradation was conserved in many actinobacterial genera, particularly in members of the Corynebacterineae, and a pathway for cholate degradation was conserved in members of the genus Rhodococcus. A pathway for testosterone and, sometimes, cholate degradation had a patchy distribution among Proteobacteria. The steroid degradation genes tended to occur within large gene clusters. Growth experiments confirmed bioinformatic predictions of steroid metabolism capacity in nine bacterial strains. The results indicate there was a single ancestral 9,10-seco-steroid degradation pathway. Gene duplication, likely in a progenitor of Rhodococcus, later gave rise to a cholate degradation pathway. Proteobacteria and additional Actinobacteria subsequently obtained a cholate degradation pathway via horizontal gene transfer, in some cases facilitated by plasmids. Catabolism of steroids appears to be an important component of the ecological niches of broad groups of Actinobacteria and individual species of Proteobacteria.

  2. Comparative Genomic Analysis Reveals Ecological Differentiation in the Genus Carnobacterium

    Science.gov (United States)

    Iskandar, Christelle F.; Borges, Frédéric; Taminiau, Bernard; Daube, Georges; Zagorec, Monique; Remenant, Benoît; Leisner, Jørgen J.; Hansen, Martin A.; Sørensen, Søren J.; Mangavel, Cécile; Cailliez-Grimal, Catherine; Revol-Junelles, Anne-Marie

    2017-01-01

    Lactic acid bacteria (LAB) differ in their ability to colonize food and animal-associated habitats: while some species are specialized and colonize a limited number of habitats, other are generalist and are able to colonize multiple animal-linked habitats. In the current study, Carnobacterium was used as a model genus to elucidate the genetic basis of these colonization differences. Analyses of 16S rRNA gene meta-barcoding data showed that C. maltaromaticum followed by C. divergens are the most prevalent species in foods derived from animals (meat, fish, dairy products), and in the gut. According to phylogenetic analyses, these two animal-adapted species belong to one of two deeply branched lineages. The second lineage contains species isolated from habitats where contact with animal is rare. Genome analyses revealed that members of the animal-adapted lineage harbor a larger secretome than members of the other lineage. The predicted cell-surface proteome is highly diversified in C. maltaromaticum and C. divergens with genes involved in adaptation to the animal milieu such as those encoding biopolymer hydrolytic enzymes, a heme uptake system, and biopolymer-binding adhesins. These species also exhibit genes for gut adaptation and respiration. In contrast, Carnobacterium species belonging to the second lineage encode a poorly diversified cell-surface proteome, lack genes for gut adaptation and are unable to respire. These results shed light on the important genomics traits required for adaptation to animal-linked habitats in generalist Carnobacterium. PMID:28337181

  3. The surprising diversity of clostridial hydrogenases: a comparative genomic perspective.

    Science.gov (United States)

    Calusinska, Magdalena; Happe, Thomas; Joris, Bernard; Wilmotte, Annick

    2010-06-01

    Among the large variety of micro-organisms capable of fermentative hydrogen production, strict anaerobes such as members of the genus Clostridium are the most widely studied. They can produce hydrogen by a reversible reduction of protons accumulated during fermentation to dihydrogen, a reaction which is catalysed by hydrogenases. Sequenced genomes provide completely new insights into the diversity of clostridial hydrogenases. Building on previous reports, we found that [FeFe] hydrogenases are not a homogeneous group of enzymes, but exist in multiple forms with different modular structures and are especially abundant in members of the genus Clostridium. This unusual diversity seems to support the central role of hydrogenases in cell metabolism. In particular, the presence of multiple putative operons encoding multisubunit [FeFe] hydrogenases highlights the fact that hydrogen metabolism is very complex in this genus. In contrast with [FeFe] hydrogenases, their [NiFe] hydrogenase counterparts, widely represented in other bacteria and archaea, are found in only a few clostridial species. Surprisingly, a heteromultimeric Ech hydrogenase, known to be an energy-converting [NiFe] hydrogenase and previously described only in methanogenic archaea and some sulfur-reducing bacteria, was found to be encoded by the genomes of four cellulolytic strains: Clostridum cellulolyticum, Clostridum papyrosolvens, Clostridum thermocellum and Clostridum phytofermentans.

  4. Comparative genomics provide insights into evolution of trichoderma nutrition style.

    Science.gov (United States)

    Xie, Bin-Bin; Qin, Qi-Long; Shi, Mei; Chen, Lei-Lei; Shu, Yan-Li; Luo, Yan; Wang, Xiao-Wei; Rong, Jin-Cheng; Gong, Zhi-Ting; Li, Dan; Sun, Cai-Yun; Liu, Gui-Ming; Dong, Xiao-Wei; Pang, Xiu-Hua; Huang, Feng; Liu, Weifeng; Chen, Xiu-Lan; Zhou, Bai-Cheng; Zhang, Yu-Zhong; Song, Xiao-Yan

    2014-02-01

    Saprotrophy on plant biomass is a recently developed nutrition strategy for Trichoderma. However, the physiology and evolution of this new nutrition strategy is still elusive. We report the deep sequencing and analysis of the genome of Trichoderma longibrachiatum, an efficient cellulase producer. The 31.7-Mb genome, smallest among the sequenced Trichoderma species, encodes fewer nutrition-related genes than saprotrophic T. reesei (Tr), including glycoside hydrolases and nonribosomal peptide synthetase-polyketide synthase. Homology and phylogenetic analyses suggest that a large number of nutrition-related genes, including GH18 chitinases, β-1,3/1,6-glucanases, cellulolytic enzymes, and hemicellulolytic enzymes, were lost in the common ancestor of T. longibrachiatum (Tl) and Tr. dN/dS (ω) calculation indicates that all the nutrition-related genes analyzed are under purifying selection. Cellulolytic enzymes, the key enzymes for saprotrophy on plant biomass, are under stronger purifying selection pressure in Tl and Tr than in mycoparasitic species, suggesting that development of the nutrition strategy of saprotrophy on plant biomass has increased the selection pressure. In addition, aspartic proteases, serine proteases, and metalloproteases are subject to stronger purifying selection pressure in Tl and Tr, suggesting that these enzymes may also play important roles in the nutrition. This study provides insights into the physiology and evolution of the nutrition strategy of Trichoderma.

  5. Comparative genomics of 12 strains of Erwinia amylovora identifies a pan-genome with a large conserved core.

    Science.gov (United States)

    Mann, Rachel A; Smits, Theo H M; Bühlmann, Andreas; Blom, Jochen; Goesmann, Alexander; Frey, Jürg E; Plummer, Kim M; Beer, Steven V; Luck, Joanne; Duffy, Brion; Rodoni, Brendan

    2013-01-01

    The plant pathogen Erwinia amylovora can be divided into two host-specific groupings; strains infecting a broad range of hosts within the Rosaceae subfamily Spiraeoideae (e.g., Malus, Pyrus, Crataegus, Sorbus) and strains infecting Rubus (raspberries and blackberries). Comparative genomic analysis of 12 strains representing distinct populations (e.g., geographic, temporal, host origin) of E. amylovora was used to describe the pan-genome of this major pathogen. The pan-genome contains 5751 coding sequences and is highly conserved relative to other phytopathogenic bacteria comprising on average 89% conserved, core genes. The chromosomes of Spiraeoideae-infecting strains were highly homogeneous, while greater genetic diversity was observed between Spiraeoideae- and Rubus-infecting strains (and among individual Rubus-infecting strains), the majority of which was attributed to variable genomic islands. Based on genomic distance scores and phylogenetic analysis, the Rubus-infecting strain ATCC BAA-2158 was genetically more closely related to the Spiraeoideae-infecting strains of E. amylovora than it was to the other Rubus-infecting strains. Analysis of the accessory genomes of Spiraeoideae- and Rubus-infecting strains has identified putative host-specific determinants including variation in the effector protein HopX1(Ea) and a putative secondary metabolite pathway only present in Rubus-infecting strains.

  6. Analysis of the Complete Mitochondrial Genome Sequence of the Diploid Cotton Gossypium raimondii by Comparative Genomics Approaches

    Directory of Open Access Journals (Sweden)

    Changwei Bi

    2016-01-01

    Full Text Available Cotton is one of the most important economic crops and the primary source of natural fiber and is an important protein source for animal feed. The complete nuclear and chloroplast (cp genome sequences of G. raimondii are already available but not mitochondria. Here, we assembled the complete mitochondrial (mt DNA sequence of G. raimondii into a circular genome of length of 676,078 bp and performed comparative analyses with other higher plants. The genome contains 39 protein-coding genes, 6 rRNA genes, and 25 tRNA genes. We also identified four larger repeats (63.9 kb, 10.6 kb, 9.1 kb, and 2.5 kb in this mt genome, which may be active in intramolecular recombination in the evolution of cotton. Strikingly, nearly all of the G. raimondii mt genome has been transferred to nucleus on Chr1, and the transfer event must be very recent. Phylogenetic analysis reveals that G. raimondii, as a member of Malvaceae, is much closer to another cotton (G. barbadense than other rosids, and the clade formed by two Gossypium species is sister to Brassicales. The G. raimondii mt genome may provide a crucial foundation for evolutionary analysis, molecular biology, and cytoplasmic male sterility in cotton and other higher plants.

  7. Comparative genomics analysis of rice and pineapple contributes to understand the chromosome number reduction and genomic changes in grasses

    Directory of Open Access Journals (Sweden)

    Jinpeng Wang

    2016-10-01

    Full Text Available Rice is one of the most researched model plant, and has a genome structure most resembling that of the grass common ancestor after a grass common tetraploidization ~100 million years ago. There has been a standing controversy whether there had been 5 or 7 basic chromosomes, before the tetraploidization, which were tackled but could not be well solved for the lacking of a sequenced and assembled outgroup plant to have a conservative genome structure. Recently, the availability of pineapple genome, which has not been subjected to the grass-common tetraploidization, provides a precious opportunity to solve the above controversy and to research into genome changes of rice and other grasses. Here, we performed a comparative genomics analysis of pineapple and rice, and found solid evidence that grass-common ancestor had 2n =2x =14 basic chromosomes before the tetraploidization and duplicated to 2n = 4x = 28 after the event. Moreover, we proposed that enormous gene missing from duplicated regions in rice should be explained by an allotetraploid produced by prominently divergent parental lines, rather than gene losses after their divergence. This means that genome fractionation might have occurred before the formation of the allotetraploid grass ancestor.

  8. Comparative genomics of 12 strains of Erwinia amylovora identifies a pan-genome with a large conserved core.

    Directory of Open Access Journals (Sweden)

    Rachel A Mann

    Full Text Available The plant pathogen Erwinia amylovora can be divided into two host-specific groupings; strains infecting a broad range of hosts within the Rosaceae subfamily Spiraeoideae (e.g., Malus, Pyrus, Crataegus, Sorbus and strains infecting Rubus (raspberries and blackberries. Comparative genomic analysis of 12 strains representing distinct populations (e.g., geographic, temporal, host origin of E. amylovora was used to describe the pan-genome of this major pathogen. The pan-genome contains 5751 coding sequences and is highly conserved relative to other phytopathogenic bacteria comprising on average 89% conserved, core genes. The chromosomes of Spiraeoideae-infecting strains were highly homogeneous, while greater genetic diversity was observed between Spiraeoideae- and Rubus-infecting strains (and among individual Rubus-infecting strains, the majority of which was attributed to variable genomic islands. Based on genomic distance scores and phylogenetic analysis, the Rubus-infecting strain ATCC BAA-2158 was genetically more closely related to the Spiraeoideae-infecting strains of E. amylovora than it was to the other Rubus-infecting strains. Analysis of the accessory genomes of Spiraeoideae- and Rubus-infecting strains has identified putative host-specific determinants including variation in the effector protein HopX1(Ea and a putative secondary metabolite pathway only present in Rubus-infecting strains.

  9. Comparative genomics in chicken and Pekin duck using FISH mapping and microarray analysis

    NARCIS (Netherlands)

    Skinner, M.; Robertson, L.B.; Tempest, H.G.; Langley, E.J.; Ioannou, D.; Fowler, K.E.; Crooijmans, R.P.M.A.

    2009-01-01

    Background: The availability of the complete chicken (Gallus gallus) genome sequence as well as a large number of chicken probes for fluorescent in-situ hybridization (FISH) and microarray resources facilitate comparative genomic studies between chicken and other bird species. In a previous study, w

  10. BGI-RIS: an integrated information resource and comparative analysis workbench for rice genomics

    DEFF Research Database (Denmark)

    Zhao, Wenming; Wang, Jing; He, Ximiao

    2004-01-01

    the application of the rice genomic information and to provide a foundation for functional and evolutionary studies of other important cereal crops, we implemented our Rice Information System (BGI-RIS), the most up-to-date integrated information resource as well as a workbench for comparative genomic analysis...

  11. The Establishment of the Pfizer-Canine Comparative Oncology and Genomics Consortium Biospecimen Repository

    Directory of Open Access Journals (Sweden)

    Christina Mazcko

    2015-07-01

    Full Text Available The Canine Comparative Oncology and Genomics Consortium (CCOGC was formed in 2004 in an effort to capitalize on the generation of a domestic dog genome sequence assembly [1], which created new opportunities to investigate canine cancers at the molecular level [2]. [...

  12. Family Competition Pheromone Genetic Algorithm for Comparative Genome Assembly

    Institute of Scientific and Technical Information of China (English)

    Chien-Hao Su; Chien-Shun Chiou; Jung-Che Kuo; Pei-Jen Wang; Cheng-Yan Kao; Hsueh-Ting Chu

    2014-01-01

    Genome assembly is a prerequisite step for analyzing next generation sequencing data and also far from being solved. Many assembly tools have been proposed and used extensively. Majority of them aim to assemble sequencing reads into contigs; however, we focus on the assembly of contigs into scaffolds in this paper. This is called scaffolding, which estimates the relative order of the contigs as well as the size of the gaps between these contigs. Pheromone trail-based genetic algorithm (PGA) was previously proposed and had decent performance according to their paper. From our previous study, we found that family competition mechanism in genetic algorithm is able to further improve the results. Therefore, we propose family competition pheromone genetic algorithm (FCPGA) and demonstrate the improvement over PGA.

  13. Comparative population genomics of maize domestication and improvement.

    Science.gov (United States)

    Hufford, Matthew B; Xu, Xun; van Heerwaarden, Joost; Pyhäjärvi, Tanja; Chia, Jer-Ming; Cartwright, Reed A; Elshire, Robert J; Glaubitz, Jeffrey C; Guill, Kate E; Kaeppler, Shawn M; Lai, Jinsheng; Morrell, Peter L; Shannon, Laura M; Song, Chi; Springer, Nathan M; Swanson-Wagner, Ruth A; Tiffin, Peter; Wang, Jun; Zhang, Gengyun; Doebley, John; McMullen, Michael D; Ware, Doreen; Buckler, Edward S; Yang, Shuang; Ross-Ibarra, Jeffrey

    2012-06-03

    Domestication and plant breeding are ongoing 10,000-year-old evolutionary experiments that have radically altered wild species to meet human needs. Maize has undergone a particularly striking transformation. Researchers have sought for decades to identify the genes underlying maize evolution, but these efforts have been limited in scope. Here, we report a comprehensive assessment of the evolution of modern maize based on the genome-wide resequencing of 75 wild, landrace and improved maize lines. We find evidence of recovery of diversity after domestication, likely introgression from wild relatives, and evidence for stronger selection during domestication than improvement. We identify a number of genes with stronger signals of selection than those previously shown to underlie major morphological changes. Finally, through transcriptome-wide analysis of gene expression, we find evidence both consistent with removal of cis-acting variation during maize domestication and improvement and suggestive of modern breeding having increased dominance in expression while targeting highly expressed genes.

  14. Comparative genomics of 274 Vibrio cholerae genomes reveals mobile functions structuring three niche dimensions

    NARCIS (Netherlands)

    Dutilh, Bas E; Thompson, Cristiane C; Vicente, Ana C P; Marin, Michel A; Lee, Clarence; Silva, Genivaldo G Z; Schmieder, Robert; Andrade, Bruno G N; Chimetto, Luciane; Cuevas, Daniel; Garza, Daniel R; Okeke, Iruka N; Aboderin, Aaron Oladipo; Spangler, Jessica; Ross, Tristen; Dinsdale, Elizabeth A; Thompson, Fabiano L; Harkins, Timothy T; Edwards, Robert A

    2014-01-01

    BACKGROUND: Vibrio cholerae is a globally dispersed pathogen that has evolved with humans for centuries, but also includes non-pathogenic environmental strains. Here, we identify the genomic variability underlying this remarkable persistence across the three major niche dimensions space, time, and h

  15. The genome sequence of Blochmannia floridanus: Comparative analysis of reduced genomes

    NARCIS (Netherlands)

    Gil, R.; Silva, F.J.; Zientz, E.; Delmotte, F.; Gonzalez-Candelas, F.; Latorre, A.; Rausell, C.; Kamerbeek, J.; Gadau, J.; Hölldobler, B.; Ham, van R.C.H.J.; Gross, R.; Moya, A.

    2003-01-01

    Bacterial symbioses are widespread among insects, probably being one of the key factors of their evolutionary success. We present the complete genome sequence of Blochmannia floridanus, the primary endosymbiont of carpenter ants. Although these ants feed on a complex diet, this symbiosis very likely

  16. Identification of conserved regulatory elements by comparative genome analysis

    Directory of Open Access Journals (Sweden)

    Jareborg Niclas

    2003-05-01

    Full Text Available Abstract Background For genes that have been successfully delineated within the human genome sequence, most regulatory sequences remain to be elucidated. The annotation and interpretation process requires additional data resources and significant improvements in computational methods for the detection of regulatory regions. One approach of growing popularity is based on the preferential conservation of functional sequences over the course of evolution by selective pressure, termed 'phylogenetic footprinting'. Mutations are more likely to be disruptive if they appear in functional sites, resulting in a measurable difference in evolution rates between functional and non-functional genomic segments. Results We have devised a flexible suite of methods for the identification and visualization of conserved transcription-factor-binding sites. The system reports those putative transcription-factor-binding sites that are both situated in conserved regions and located as pairs of sites in equivalent positions in alignments between two orthologous sequences. An underlying collection of metazoan transcription-factor-binding profiles was assembled to facilitate the study. This approach results in a significant improvement in the detection of transcription-factor-binding sites because of an increased signal-to-noise ratio, as demonstrated with two sets of promoter sequences. The method is implemented as a graphical web application, ConSite, which is at the disposal of the scientific community at http://www.phylofoot.org/. Conclusions Phylogenetic footprinting dramatically improves the predictive selectivity of bioinformatic approaches to the analysis of promoter sequences. ConSite delivers unparalleled performance using a novel database of high-quality binding models for metazoan transcription factors. With a dynamic interface, this bioinformatics tool provides broad access to promoter analysis with phylogenetic footprinting.

  17. Comparative Genomic Analysis of Human Fungal Pathogens Causing Paracoccidioidomycosis

    Science.gov (United States)

    Desjardins, Christopher A.; Champion, Mia D.; Holder, Jason W.; Muszewska, Anna; Goldberg, Jonathan; Bailão, Alexandre M.; Brigido, Marcelo Macedo; Ferreira, Márcia Eliana da Silva; Garcia, Ana Maria; Grynberg, Marcin; Gujja, Sharvari; Heiman, David I.; Henn, Matthew R.; Kodira, Chinnappa D.; León-Narváez, Henry; Longo, Larissa V. G.; Ma, Li-Jun; Malavazi, Iran; Matsuo, Alisson L.; Morais, Flavia V.; Pereira, Maristela; Rodríguez-Brito, Sabrina; Sakthikumar, Sharadha; Salem-Izacc, Silvia M.; Sykes, Sean M.; Teixeira, Marcus Melo; Vallejo, Milene C.; Walter, Maria Emília Machado Telles; Yandava, Chandri; Young, Sarah; Zeng, Qiandong; Zucker, Jeremy; Felipe, Maria Sueli; Goldman, Gustavo H.; Haas, Brian J.; McEwen, Juan G.; Nino-Vega, Gustavo; Puccia, Rosana; San-Blas, Gioconda; Soares, Celia Maria de Almeida; Birren, Bruce W.; Cuomo, Christina A.

    2011-01-01

    Paracoccidioides is a fungal pathogen and the cause of paracoccidioidomycosis, a health-threatening human systemic mycosis endemic to Latin America. Infection by Paracoccidioides, a dimorphic fungus in the order Onygenales, is coupled with a thermally regulated transition from a soil-dwelling filamentous form to a yeast-like pathogenic form. To better understand the genetic basis of growth and pathogenicity in Paracoccidioides, we sequenced the genomes of two strains of Paracoccidioides brasiliensis (Pb03 and Pb18) and one strain of Paracoccidioides lutzii (Pb01). These genomes range in size from 29.1 Mb to 32.9 Mb and encode 7,610 to 8,130 genes. To enable genetic studies, we mapped 94% of the P. brasiliensis Pb18 assembly onto five chromosomes. We characterized gene family content across Onygenales and related fungi, and within Paracoccidioides we found expansions of the fungal-specific kinase family FunK1. Additionally, the Onygenales have lost many genes involved in carbohydrate metabolism and fewer genes involved in protein metabolism, resulting in a higher ratio of proteases to carbohydrate active enzymes in the Onygenales than their relatives. To determine if gene content correlated with growth on different substrates, we screened the non-pathogenic onygenale Uncinocarpus reesii, which has orthologs for 91% of Paracoccidioides metabolic genes, for growth on 190 carbon sources. U. reesii showed growth on a limited range of carbohydrates, primarily basic plant sugars and cell wall components; this suggests that Onygenales, including dimorphic fungi, can degrade cellulosic plant material in the soil. In addition, U. reesii grew on gelatin and a wide range of dipeptides and amino acids, indicating a preference for proteinaceous growth substrates over carbohydrates, which may enable these fungi to also degrade animal biomass. These capabilities for degrading plant and animal substrates suggest a duality in lifestyle that could enable pathogenic species of

  18. Comparative genomic analysis of human fungal pathogens causing paracoccidioidomycosis.

    Directory of Open Access Journals (Sweden)

    Christopher A Desjardins

    2011-10-01

    Full Text Available Paracoccidioides is a fungal pathogen and the cause of paracoccidioidomycosis, a health-threatening human systemic mycosis endemic to Latin America. Infection by Paracoccidioides, a dimorphic fungus in the order Onygenales, is coupled with a thermally regulated transition from a soil-dwelling filamentous form to a yeast-like pathogenic form. To better understand the genetic basis of growth and pathogenicity in Paracoccidioides, we sequenced the genomes of two strains of Paracoccidioides brasiliensis (Pb03 and Pb18 and one strain of Paracoccidioides lutzii (Pb01. These genomes range in size from 29.1 Mb to 32.9 Mb and encode 7,610 to 8,130 genes. To enable genetic studies, we mapped 94% of the P. brasiliensis Pb18 assembly onto five chromosomes. We characterized gene family content across Onygenales and related fungi, and within Paracoccidioides we found expansions of the fungal-specific kinase family FunK1. Additionally, the Onygenales have lost many genes involved in carbohydrate metabolism and fewer genes involved in protein metabolism, resulting in a higher ratio of proteases to carbohydrate active enzymes in the Onygenales than their relatives. To determine if gene content correlated with growth on different substrates, we screened the non-pathogenic onygenale Uncinocarpus reesii, which has orthologs for 91% of Paracoccidioides metabolic genes, for growth on 190 carbon sources. U. reesii showed growth on a limited range of carbohydrates, primarily basic plant sugars and cell wall components; this suggests that Onygenales, including dimorphic fungi, can degrade cellulosic plant material in the soil. In addition, U. reesii grew on gelatin and a wide range of dipeptides and amino acids, indicating a preference for proteinaceous growth substrates over carbohydrates, which may enable these fungi to also degrade animal biomass. These capabilities for degrading plant and animal substrates suggest a duality in lifestyle that could enable pathogenic

  19. Comparative genomics of the bacterial genus Listeria: Genome evolution is characterized by limited gene acquisition and limited gene loss

    Directory of Open Access Journals (Sweden)

    Barker Melissa

    2010-12-01

    Full Text Available Abstract Background The bacterial genus Listeria contains pathogenic and non-pathogenic species, including the pathogens L. monocytogenes and L. ivanovii, both of which carry homologous virulence gene clusters such as the prfA cluster and clusters of internalin genes. Initial evidence for multiple deletions of the prfA cluster during the evolution of Listeria indicates that this genus provides an interesting model for studying the evolution of virulence and also presents practical challenges with regard to definition of pathogenic strains. Results To better understand genome evolution and evolution of virulence characteristics in Listeria, we used a next generation sequencing approach to generate draft genomes for seven strains representing Listeria species or clades for which genome sequences were not available. Comparative analyses of these draft genomes and six publicly available genomes, which together represent the main Listeria species, showed evidence for (i a pangenome with 2,032 core and 2,918 accessory genes identified to date, (ii a critical role of gene loss events in transition of Listeria species from facultative pathogen to saprotroph, even though a consistent pattern of gene loss seemed to be absent, and a number of isolates representing non-pathogenic species still carried some virulence associated genes, and (iii divergence of modern pathogenic and non-pathogenic Listeria species and strains, most likely circa 47 million years ago, from a pathogenic common ancestor that contained key virulence genes. Conclusions Genome evolution in Listeria involved limited gene loss and acquisition as supported by (i a relatively high coverage of the predicted pan-genome by the observed pan-genome, (ii conserved genome size (between 2.8 and 3.2 Mb, and (iii a highly syntenic genome. Limited gene loss in Listeria did include loss of virulence associated genes, likely associated with multiple transitions to a saprotrophic lifestyle. The genus

  20. The 19 genomes of Drosophila: a BAC library resource for genus-wide and genome-scale comparative evolutionary research.

    Science.gov (United States)

    Song, Xiang; Goicoechea, Jose Luis; Ammiraju, Jetty S S; Luo, Meizhong; He, Ruifeng; Lin, Jinke; Lee, So-Jeong; Sisneros, Nicholas; Watts, Tom; Kudrna, David A; Golser, Wolfgang; Ashley, Elizabeth; Collura, Kristi; Braidotti, Michele; Yu, Yeisoo; Matzkin, Luciano M; McAllister, Bryant F; Markow, Therese Ann; Wing, Rod A

    2011-04-01

    The genus Drosophila has been the subject of intense comparative phylogenomics characterization to provide insights into genome evolution under diverse biological and ecological contexts and to functionally annotate the Drosophila melanogaster genome, a model system for animal and insect genetics. Recent sequencing of 11 additional Drosophila species from various divergence points of the genus is a first step in this direction. However, to fully reap the benefits of this resource, the Drosophila community is faced with two critical needs: i.e., the expansion of genomic resources from a much broader range of phylogenetic diversity and the development of additional resources to aid in finishing the existing draft genomes. To address these needs, we report the first synthesis of a comprehensive set of bacterial artificial chromosome (BAC) resources for 19 Drosophila species from all three subgenera. Ten libraries were derived from the exact source used to generate 10 of the 12 draft genomes, while the rest were generated from a strategically selected set of species on the basis of salient ecological and life history features and their phylogenetic positions. The majority of the new species have at least one sequenced reference genome for immediate comparative benefit. This 19-BAC library set was rigorously characterized and shown to have large insert sizes (125-168 kb), low nonrecombinant clone content (0.3-5.3%), and deep coverage (9.1-42.9×). Further, we demonstrated the utility of this BAC resource for generating physical maps of targeted loci, refining draft sequence assemblies and identifying potential genomic rearrangements across the phylogeny.

  1. CMG-biotools, a free workbench for basic comparative microbial genomics.

    Directory of Open Access Journals (Sweden)

    Tammi Vesth

    Full Text Available BACKGROUND: Today, there are more than a hundred times as many sequenced prokaryotic genomes than were present in the year 2000. The economical sequencing of genomic DNA has facilitated a whole new approach to microbial genomics. The real power of genomics is manifested through comparative genomics that can reveal strain specific characteristics, diversity within species and many other aspects. However, comparative genomics is a field not easily entered into by scientists with few computational skills. The CMG-biotools package is designed for microbiologists with limited knowledge of computational analysis and can be used to perform a number of analyses and comparisons of genomic data. RESULTS: The CMG-biotools system presents a stand-alone interface for comparative microbial genomics. The package is a customized operating system, based on Xubuntu 10.10, available through the open source Ubuntu project. The system can be installed on a virtual computer, allowing the user to run the system alongside any other operating system. Source codes for all programs are provided under GNU license, which makes it possible to transfer the programs to other systems if so desired. We here demonstrate the package by comparing and analyzing the diversity within the class Negativicutes, represented by 31 genomes including 10 genera. The analyses include 16S rRNA phylogeny, basic DNA and codon statistics, proteome comparisons using BLAST and graphical analyses of DNA structures. CONCLUSION: This paper shows the strength and diverse use of the CMG-biotools system. The system can be installed on a vide range of host operating systems and utilizes as much of the host computer as desired. It allows the user to compare multiple genomes, from various sources using standardized data formats and intuitive visualizations of results. The examples presented here clearly shows that users with limited computational experience can perform complicated analysis without much

  2. Comparative genomics of the syndecans defines an ancestral genomic context associated with matrilins in vertebrates

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    Adams Josephine C

    2006-04-01

    Full Text Available Abstract Background The syndecans are the major family of transmembrane proteoglycans in animals and are known for multiple roles in cell interactions and growth factor signalling during development, inflammatory response, wound-repair and tumorigenesis. Although syndecans have been cloned from several invertebrate and vertebrate species, the extent of conservation of the family across the animal kingdom is unknown and there are gaps in our knowledge of chordate syndecans. Here, we develop a new level of knowledge for the whole syndecan family, by combining molecular phylogeny of syndecan protein sequences with analysis of the genomic contexts of syndecan genes in multiple vertebrate organisms. Results We identified syndecan-encoding sequences in representative Cnidaria and throughout the Bilateria. The C1 and C2 regions of the cytoplasmic domain are highly conserved throughout the animal kingdom. We identified in the variable region a universally-conserved leucine residue and a tyrosine residue that is conserved throughout the Bilateria. Of all the genomes examined, only tetrapod and fish genomes encode multiple syndecans. No syndecan-1 was identified in fish. The genomic context of each vertebrate syndecan gene is syntenic between human, mouse and chicken, and this conservation clearly extends to syndecan-2 and -3 in T. nigroviridis. In addition, tetrapod syndecans were found to be encoded from paralogous chromosomal regions that also contain the four members of the matrilin family. Whereas the matrilin-3 and syndecan-1 genes are adjacent in tetrapods, this chromosomal region appears to have undergone extensive lineage-specific rearrangements in fish. Conclusion Throughout the animal kingdom, syndecan extracellular domains have undergone rapid change and elements of the cytoplasmic domains have been very conserved. The four syndecan genes of vertebrates are syntenic across tetrapods, and synteny of the syndecan-2 and -3 genes is apparent

  3. Comparative Genome Analyses of Vibrio anguillarum Strains Reveal a Link with Pathogenicity Traits

    Science.gov (United States)

    Castillo, Daniel; Alvise, Paul D.; Xu, Ruiqi; Zhang, Faxing; Middelboe, Mathias

    2017-01-01

    ABSTRACT Vibrio anguillarum is a marine bacterium that can cause vibriosis in many fish and shellfish species, leading to high mortalities and economic losses in aquaculture. Although putative virulence factors have been identified, the mechanism of pathogenesis of V. anguillarum is not fully understood. Here, we analyzed whole-genome sequences of a collection of V. anguillarum strains and compared them to virulence of the strains as determined in larval challenge assays. Previously identified virulence factors were globally distributed among the strains, with some genetic diversity. However, the pan-genome revealed that six out of nine high-virulence strains possessed a unique accessory genome that was attributed to pathogenic genomic islands, prophage-like elements, virulence factors, and a new set of gene clusters involved in biosynthesis, modification, and transport of polysaccharides. In contrast, V. anguillarum strains that were medium to nonvirulent had a high degree of genomic homogeneity. Finally, we found that a phylogeny based on the core genomes clustered the strains with moderate to no virulence, while six out of nine high-virulence strains represented phylogenetically separate clusters. Hence, we suggest a link between genotype and virulence characteristics of Vibrio anguillarum, which can be used to unravel the molecular evolution of V. anguillarum and can also be important from survey and diagnostic perspectives. IMPORTANCE Comparative genome analysis of strains of a pathogenic bacterial species can be a powerful tool to discover acquisition of mobile genetic elements related to virulence. Here, we compared 28 V. anguillarum strains that differed in virulence in fish larval models. By pan-genome analyses, we found that six of nine highly virulent strains had a unique core and accessory genome. In contrast, V. anguillarum strains that were medium to nonvirulent had low genomic diversity. Integration of genomic and phenotypic features provides

  4. Comparative Analysis of Fatty Acid Desaturases in Cyanobacterial Genomes

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    Xiaoyuan Chi

    2008-01-01

    Full Text Available Fatty acid desaturases are enzymes that introduce double bonds into the hydrocarbon chains of fatty acids. The fatty acid desaturases from 37 cyanobacterial genomes were identified and classified based upon their conserved histidine-rich motifs and phylogenetic analysis, which help to determine the amounts and distributions of desaturases in cyanobacterial species. The filamentous or N2-fixing cyanobacteria usually possess more types of fatty acid desaturases than that of unicellular species. The pathway of acyl-lipid desaturation for unicellular marine cyanobacteria Synechococcus and Prochlorococcus differs from that of other cyanobacteria, indicating different phylogenetic histories of the two genera from other cyanobacteria isolated from freshwater, soil, or symbiont. Strain Gloeobacter violaceus PCC 7421 was isolated from calcareous rock and lacks thylakoid membranes. The types and amounts of desaturases of this strain are distinct to those of other cyanobacteria, reflecting the earliest divergence of it from the cyanobacterial line. Three thermophilic unicellular strains, Thermosynechococcus elongatus BP-1 and two Synechococcus Yellowstone species, lack highly unsaturated fatty acids in lipids and contain only one Δ9 desaturase in contrast with mesophilic strains, which is probably due to their thermic habitats. Thus, the amounts and types of fatty acid desaturases are various among different cyanobacterial species, which may result from the adaption to environments in evolution.

  5. Investigating hookworm genomes by comparative analysis of two Ancylostoma species

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    Kapulkin Wadim

    2005-04-01

    Full Text Available Abstract Background Hookworms, infecting over one billion people, are the mostly closely related major human parasites to the model nematode Caenorhabditis elegans. Applying genomics techniques to these species, we analyzed 3,840 and 3,149 genes from Ancylostoma caninum and A. ceylanicum. Results Transcripts originated from libraries representing infective L3 larva, stimulated L3, arrested L3, and adults. Most genes are represented in single stages including abundant transcripts like hsp-20 in infective L3 and vit-3 in adults. Over 80% of the genes have homologs in C. elegans, and nearly 30% of these were with observable RNA interference phenotypes. Homologies were identified to nematode-specific and clade V specific gene families. To study the evolution of hookworm genes, 574 A. caninum / A. ceylanicum orthologs were identified, all of which were found to be under purifying selection with distribution ratios of nonsynonymous to synonymous amino acid substitutions similar to that reported for C. elegans / C. briggsae orthologs. The phylogenetic distance between A. caninum and A. ceylanicum is almost identical to that for C. elegans / C. briggsae. Conclusion The genes discovered should substantially accelerate research toward better understanding of the parasites' basic biology as well as new therapies including vaccines and novel anthelmintics.

  6. An orphan gyrB in the Mycobacterium smegmatis genome uncovered by comparative genomics

    Indian Academy of Sciences (India)

    P. Jain; V. Nagaraja

    2002-11-01

    DNA gyrase is an essential topoisomerase found in all bacteria. It is encoded by gyrB and gyrA genes. These genes are organized differently in different bacteria. Direct comparison of Mycobacterium tuberculosis and Mycobacterium smegmatis genomes reveals presence of an additional gyrB in M. smegmatis flanked by novel genes. Analysis of the amino acid sequence of GyrB from different organisms suggests that the orphan GyrB in M. smegmatis may have an important cellular role.

  7. Integrating cytogenetics and genomics in comparative evolutionary studies of cichlid fish

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    Mazzuchelli Juliana

    2012-09-01

    Full Text Available Abstract Background The availability of a large number of recently sequenced vertebrate genomes opens new avenues to integrate cytogenetics and genomics in comparative and evolutionary studies. Cytogenetic mapping can offer alternative means to identify conserved synteny shared by distinct genomes and also to define genome regions that are still not fine characterized even after wide-ranging nucleotide sequence efforts. An efficient way to perform comparative cytogenetic mapping is based on BAC clones mapping by fluorescence in situ hybridization. In this report, to address the knowledge gap on the genome evolution in cichlid fishes, BAC clones of an Oreochromis niloticus library covering the linkage groups (LG 1, 3, 5, and 7 were mapped onto the chromosomes of 9 African cichlid species. The cytogenetic mapping data were also integrated with BAC-end sequences information of O. niloticus and comparatively analyzed against the genome of other fish species and vertebrates. Results The location of BACs from LG1, 3, 5, and 7 revealed a strong chromosomal conservation among the analyzed cichlid species genomes, which evidenced a synteny of the markers of each LG. Comparative in silico analysis also identified large genomic blocks that were conserved in distantly related fish groups and also in other vertebrates. Conclusions Although it has been suggested that fishes contain plastic genomes with high rates of chromosomal rearrangements and probably low rates of synteny conservation, our results evidence that large syntenic chromosome segments have been maintained conserved during evolution, at least for the considered markers. Additionally, our current cytogenetic mapping efforts integrated with genomic approaches conduct to a new perspective to address important questions involving chromosome evolution in fishes.

  8. Organization and comparative analysis of the mitochondrial genomes of bioluminescent Elateroidea (Coleoptera: Polyphaga).

    Science.gov (United States)

    Amaral, Danilo T; Mitani, Yasuo; Ohmiya, Yoshihiro; Viviani, Vadim R

    2016-07-25

    Mitochondrial genome organization in the Elateroidea superfamily (Coleoptera), which include the main families of bioluminescent beetles, has been poorly studied and lacking information about Phengodidae family. We sequenced the mitochondrial genomes of Neotropical Lampyridae (Bicellonycha lividipennis), Phengodidae (Brasilocerus sp.2 and Phrixothrix hirtus) and Elateridae (Pyrearinus termitilluminans, Hapsodrilus ignifer and Teslasena femoralis). All species had a typical insect mitochondrial genome except for the following: in the elaterid T. femoralis genome there is a non-coding region between NADH2 and tRNA-Trp; in the phengodids Brasilocerus sp.2 and P. hirtus genomes we did not find the tRNA-Ile and tRNA-Gln. The P. hirtus genome showed a ~1.6kb non-coding region, the rearrangement of tRNA-Tyr, a new tRNA-Leu copy, and several regions with higher AT contents. Phylogenetics analysis using Bayesian and ML models indicated that the Phengodidae+Rhagophthalmidae are closely related to Lampyridae family, and included Drilus flavescens (Drilidae) as an internal clade within Elateridae. This is the first report that compares the mitochondrial genomes organization of the three main families of bioluminescent Elateroidea, including the first Neotropical Lampyridae and Phengodidae. The losses of tRNAs, and translocation and duplication events found in Phengodidae mt genomes, mainly in P. hirtus, may indicate different evolutionary rates in these mitochondrial genomes. The mitophylogenomics analysis indicates the monophyly of the three bioluminescent families and a closer relationship between Lampyridae and Phengodidae/Rhagophthalmidae, in contrast with previous molecular analysis.

  9. New Markov Model Approaches to Deciphering Microbial Genome Function and Evolution: Comparative Genomics of Laterally Transferred Genes

    Energy Technology Data Exchange (ETDEWEB)

    Borodovsky, M.

    2013-04-11

    Algorithmic methods for gene prediction have been developed and successfully applied to many different prokaryotic genome sequences. As the set of genes in a particular genome is not homogeneous with respect to DNA sequence composition features, the GeneMark.hmm program utilizes two Markov models representing distinct classes of protein coding genes denoted "typical" and "atypical". Atypical genes are those whose DNA features deviate significantly from those classified as typical and they represent approximately 10% of any given genome. In addition to the inherent interest of more accurately predicting genes, the atypical status of these genes may also reflect their separate evolutionary ancestry from other genes in that genome. We hypothesize that atypical genes are largely comprised of those genes that have been relatively recently acquired through lateral gene transfer (LGT). If so, what fraction of atypical genes are such bona fide LGTs? We have made atypical gene predictions for all fully completed prokaryotic genomes; we have been able to compare these results to other "surrogate" methods of LGT prediction.

  10. Comparative Genome Analysis Provides Insights into the Pathogenicity of Flavobacterium psychrophilum

    Science.gov (United States)

    Castillo, Daniel; Christiansen, Rói Hammershaimb; Dalsgaard, Inger; Madsen, Lone; Espejo, Romilio

    2016-01-01

    Flavobacterium psychrophilum is a fish pathogen in salmonid aquaculture worldwide that causes cold water disease (CWD) and rainbow trout fry syndrome (RTFS). Comparative genome analyses of 11 F. psychrophilum isolates representing temporally and geographically distant populations were used to describe the F. psychrophilum pan-genome and to examine virulence factors, prophages, CRISPR arrays, and genomic islands present in the genomes. Analysis of the genomic DNA sequences were complemented with selected phenotypic characteristics of the strains. The pan genome analysis showed that F. psychrophilum could hold at least 3373 genes, while the core genome contained 1743 genes. On average, 67 new genes were detected for every new genome added to the analysis, indicating that F. psychrophilum possesses an open pan genome. The putative virulence factors were equally distributed among isolates, independent of geographic location, year of isolation and source of isolates. Only one prophage-related sequence was found which corresponded to the previously described prophage 6H, and appeared in 5 out of 11 isolates. CRISPR array analysis revealed two different loci with dissimilar spacer content, which only matched one sequence in the database, the temperate bacteriophage 6H. Genomic Islands (GIs) were identified in F. psychrophilum isolates 950106-1/1 and CSF 259–93, associated with toxins and antibiotic resistance. Finally, phenotypic characterization revealed a high degree of similarity among the strains with respect to biofilm formation and secretion of extracellular enzymes. Global scale dispersion of virulence factors in the genomes and the abilities for biofilm formation, hemolytic activity and secretion of extracellular enzymes among the strains suggested that F. psychrophilum isolates have a similar mode of action on adhesion, colonization and destruction of fish tissues across large spatial and temporal scales of occurrence. Overall, the genomic characterization and

  11. Analysis of the Complete Chloroplast Genome of a Medicinal Plant, Dianthus superbus var. longicalyncinus, from a Comparative Genomics Perspective.

    Science.gov (United States)

    Raman, Gurusamy; Park, SeonJoo

    2015-01-01

    Dianthus superbus var. longicalycinus is an economically important traditional Chinese medicinal plant that is also used for ornamental purposes. In this study, D. superbus was compared to its closely related family of Caryophyllaceae chloroplast (cp) genomes such as Lychnis chalcedonica and Spinacia oleracea. D. superbus had the longest large single copy (LSC) region (82,805 bp), with some variations in the inverted repeat region A (IRA)/LSC regions. The IRs underwent both expansion and constriction during evolution of the Caryophyllaceae family; however, intense variations were not identified. The pseudogene ribosomal protein subunit S19 (rps19) was identified at the IRA/LSC junction, but was not present in the cp genome of other Caryophyllaceae family members. The translation initiation factor IF-1 (infA) and ribosomal protein subunit L23 (rpl23) genes were absent from the Dianthus cp genome. When the cp genome of Dianthus was compared with 31 other angiosperm lineages, the infA gene was found to have been lost in most members of rosids, solanales of asterids and Lychnis of Caryophyllales, whereas rpl23 gene loss or pseudogization had occurred exclusively in Caryophyllales. Nevertheless, the cp genome of Dianthus and Spinacia has two introns in the proteolytic subunit of ATP-dependent protease (clpP) gene, but Lychnis has lost introns from the clpP gene. Furthermore, phylogenetic analysis of individual protein-coding genes infA and rpl23 revealed that gene loss or pseudogenization occurred independently in the cp genome of Dianthus. Molecular phylogenetic analysis also demonstrated a sister relationship between Dianthus and Lychnis based on 78 protein-coding sequences. The results presented herein will contribute to studies of the evolution, molecular biology and genetic engineering of the medicinal and ornamental plant, D. superbus var. longicalycinus.

  12. Analysis of the Complete Chloroplast Genome of a Medicinal Plant, Dianthus superbus var. longicalyncinus, from a Comparative Genomics Perspective.

    Directory of Open Access Journals (Sweden)

    Gurusamy Raman

    Full Text Available Dianthus superbus var. longicalycinus is an economically important traditional Chinese medicinal plant that is also used for ornamental purposes. In this study, D. superbus was compared to its closely related family of Caryophyllaceae chloroplast (cp genomes such as Lychnis chalcedonica and Spinacia oleracea. D. superbus had the longest large single copy (LSC region (82,805 bp, with some variations in the inverted repeat region A (IRA/LSC regions. The IRs underwent both expansion and constriction during evolution of the Caryophyllaceae family; however, intense variations were not identified. The pseudogene ribosomal protein subunit S19 (rps19 was identified at the IRA/LSC junction, but was not present in the cp genome of other Caryophyllaceae family members. The translation initiation factor IF-1 (infA and ribosomal protein subunit L23 (rpl23 genes were absent from the Dianthus cp genome. When the cp genome of Dianthus was compared with 31 other angiosperm lineages, the infA gene was found to have been lost in most members of rosids, solanales of asterids and Lychnis of Caryophyllales, whereas rpl23 gene loss or pseudogization had occurred exclusively in Caryophyllales. Nevertheless, the cp genome of Dianthus and Spinacia has two introns in the proteolytic subunit of ATP-dependent protease (clpP gene, but Lychnis has lost introns from the clpP gene. Furthermore, phylogenetic analysis of individual protein-coding genes infA and rpl23 revealed that gene loss or pseudogenization occurred independently in the cp genome of Dianthus. Molecular phylogenetic analysis also demonstrated a sister relationship between Dianthus and Lychnis based on 78 protein-coding sequences. The results presented herein will contribute to studies of the evolution, molecular biology and genetic engineering of the medicinal and ornamental plant, D. superbus var. longicalycinus.

  13. MIPS PlantsDB: a database framework for comparative plant genome research.

    Science.gov (United States)

    Nussbaumer, Thomas; Martis, Mihaela M; Roessner, Stephan K; Pfeifer, Matthias; Bader, Kai C; Sharma, Sapna; Gundlach, Heidrun; Spannagl, Manuel

    2013-01-01

    The rapidly increasing amount of plant genome (sequence) data enables powerful comparative analyses and integrative approaches and also requires structured and comprehensive information resources. Databases are needed for both model and crop plant organisms and both intuitive search/browse views and comparative genomics tools should communicate the data to researchers and help them interpret it. MIPS PlantsDB (http://mips.helmholtz-muenchen.de/plant/genomes.jsp) was initially described in NAR in 2007 [Spannagl,M., Noubibou,O., Haase,D., Yang,L., Gundlach,H., Hindemitt, T., Klee,K., Haberer,G., Schoof,H. and Mayer,K.F. (2007) MIPSPlantsDB-plant database resource for integrative and comparative plant genome research. Nucleic Acids Res., 35, D834-D840] and was set up from the start to provide data and information resources for individual plant species as well as a framework for integrative and comparative plant genome research. PlantsDB comprises database instances for tomato, Medicago, Arabidopsis, Brachypodium, Sorghum, maize, rice, barley and wheat. Building up on that, state-of-the-art comparative genomics tools such as CrowsNest are integrated to visualize and investigate syntenic relationships between monocot genomes. Results from novel genome analysis strategies targeting the complex and repetitive genomes of triticeae species (wheat and barley) are provided and cross-linked with model species. The MIPS Repeat Element Database (mips-REdat) and Catalog (mips-REcat) as well as tight connections to other databases, e.g. via web services, are further important components of PlantsDB.

  14. Comparative genomics and stx phage characterization of LEE-negative Shiga toxin-producing Escherichia coli

    Directory of Open Access Journals (Sweden)

    Susan Renee Steyert

    2012-11-01

    Full Text Available Infection by Escherichia coli and Shigella species are among the leading causes of death due to diarrheal disease in the world. Shiga toxin producing Escherichia coli (STEC that do not encode the locus of enterocyte effacement (LEE-negative STEC often possess Shiga toxin gene variants and have been isolated from humans and a variety of animal sources. In this study, we compare the genomes of nine LEE-negative STEC harboring various stx alleles with four complete reference LEE-positive STEC isolates. Compared to a representative collection of prototype E. coli and Shigella isolates representing each of the pathotypes, the whole genome phylogeny demonstrated that these isolates are diverse. Whole genome comparative analysis of the 13 genomes revealed that in addition to the absence of the LEE pathogenicity island, phage encoded genes including non-LEE encoded effectors, were absent from all nine LEE-negative STEC genomes. Several plasmid-encoded virulence factors reportedly identified in LEE-negative STEC isolates were identified in only a subset of the nine LEE-negative isolates further confirming the diversity of this group. In combination with whole genome analysis, we characterized the lambdoid phages harboring the various stx alleles and determined their genomic insertion sites. Although the integrase gene sequence corresponded with genomic location, it was not correlated with stx variant, further highlighting the mosaic nature of these phages. The transcription of these phages in different genomic backgrounds was examined. Expression of the Shiga toxin genes, stx1 and/or stx2, as well as the Q genes, were examined with quantitative reverse transcriptase polymerase chain reaction (qRT-PCR assays. A wide range of basal and induced toxin induction was observed. Overall, this is a first significant foray into the genome space of this unexplored group of emerging and divergent pathogens.

  15. Complete genome sequence and comparative genome analysis of a new special Yersinia enterocolitica.

    Science.gov (United States)

    Shi, Guoxiang; Su, Mingming; Liang, Junrong; Duan, Ran; Gu, Wenpeng; Xiao, Yuchun; Zhang, Zhewen; Qiu, Haiyan; Zhang, Zheng; Li, Yi; Zhang, Xiaohe; Ling, Yunchao; Song, Lai; Chen, Meili; Zhao, Yongbing; Wu, Jiayan; Jing, Huaiqi; Xiao, Jingfa; Wang, Xin

    2016-09-01

    Yersinia enterocolitica is the most diverse species among the Yersinia genera and shows more polymorphism, especially for the non-pathogenic strains. Individual non-pathogenic Y. enterocolitica strains are wrongly identified because of atypical phenotypes. In this study, we isolated an unusual Y. enterocolitica strain LC20 from Rattus norvegicus. The strain did not utilize urea and could not be classified as the biotype. API 20E identified Escherichia coli; however, it grew well at 25 °C, but E. coli grew well at 37 °C. We analyzed the genome of LC20 and found the whole chromosome of LC20 was collinear with Y. enterocolitica 8081, and the urease gene did not exist on the genome which is consistent with the result of API 20E. Also, the 16 S and 23 SrRNA gene of LC20 lay on a branch of Y. enterocolitica. Furthermore, the core-based and pan-based phylogenetic trees showed that LC20 was classified into the Y. enterocolitica cluster. Two plasmids (80 and 50 k) from LC20 shared low genetic homology with pYV from the Yersinia genus, one was an ancestral Yersinia plasmid and the other was novel encoding a number of transposases. Some pathogenic and non-pathogenic Y. enterocolitica-specific genes coexisted in LC20. Thus, although it could not be classified into any Y. enterocolitica biotype due to its special biochemical metabolism, we concluded the LC20 was a Y. enterocolitica strain because its genome was similar to other Y. enterocolitica and it might be a strain with many mutations and combinations emerging in the processes of its evolution.

  16. Comparative genomic analysis as a tool for biologicaldiscovery

    Energy Technology Data Exchange (ETDEWEB)

    Nobrega, Marcelo A.; Pennacchio, Len A.

    2003-03-30

    Biology is a discipline rooted in comparisons. Comparative physiology has assembled a detailed catalogue of the biological similarities and differences between species, revealing insights into how life has adapted to fill a wide-range of environmental niches. For example, the oxygen and carbon dioxide carrying capacity of vertebrate has evolved to provide strong advantages for species respiring at sea level, at high elevation or within water. Comparative- anatomy, -biochemistry, -pharmacology, -immunology and -cell biology have provided the fundamental paradigms from which each discipline has grown.

  17. PLAZA 3.0: an access point for plant comparative genomics.

    Science.gov (United States)

    Proost, Sebastian; Van Bel, Michiel; Vaneechoutte, Dries; Van de Peer, Yves; Inzé, Dirk; Mueller-Roeber, Bernd; Vandepoele, Klaas

    2015-01-01

    Comparative sequence analysis has significantly altered our view on the complexity of genome organization and gene functions in different kingdoms. PLAZA 3.0 is designed to make comparative genomics data for plants available through a user-friendly web interface. Structural and functional annotation, gene families, protein domains, phylogenetic trees and detailed information about genome organization can easily be queried and visualized. Compared with the first version released in 2009, which featured nine organisms, the number of integrated genomes is more than four times higher, and now covers 37 plant species. The new species provide a wider phylogenetic range as well as a more in-depth sampling of specific clades, and genomes of additional crop species are present. The functional annotation has been expanded and now comprises data from Gene Ontology, MapMan, UniProtKB/Swiss-Prot, PlnTFDB and PlantTFDB. Furthermore, we improved the algorithms to transfer functional annotation from well-characterized plant genomes to other species. The additional data and new features make PLAZA 3.0 (http://bioinformatics.psb.ugent.be/plaza/) a versatile and comprehensible resource for users wanting to explore genome information to study different aspects of plant biology, both in model and non-model organisms.

  18. Parallel WGA and WTA for Comparative Genome and Transcriptome NGS Analysis Using Tiny Cell Numbers.

    Science.gov (United States)

    Korfhage, Christian; Fricke, Evelyn; Meier, Andreas

    2015-07-01

    Genomic DNA determines how and when the transcriptome is changed by a trigger or environmental change and how cellular metabolism is influenced. Comparative genome and transcriptome analysis of the same cell sample links a defined genome with all changes in the bases, structure, or numbers of the transcriptome. However, comparative genome and transcriptome analysis using next-generation sequencing (NGS) or real-time PCR is often limited by the small amount of sample available. In mammals, the amount of DNA and RNA in a single cell is ∼10 picograms, but deep analysis of the genome and transcriptome currently requires several hundred nanograms of nucleic acids for library preparation for NGS sequencing. Consequently, accurate whole-genome amplification (WGA) and whole-transcriptome amplification (WTA) is required for such quantitative analysis. This unit describes how the genome and the transcriptome of a tiny number of cells can be amplified in a highly parallel and comparable process. Protocols for quality control of amplified DNA and application of amplified DNA for NGS are included.

  19. Genome Sequencing and Comparative Genomics Analysis Revealed Pathogenic Potential in Penicillium capsulatum as a Novel Fungal Pathogen Belonging to Eurotiales

    Science.gov (United States)

    Yang, Ying; Chen, Min; Li, Zongwei; Al-Hatmi, Abdullah M. S.; de Hoog, Sybren; Pan, Weihua; Ye, Qiang; Bo, Xiaochen; Li, Zhen; Wang, Shengqi; Wang, Junzhi; Chen, Huipeng; Liao, Wanqing

    2016-01-01

    Penicillium capsulatum is a rare Penicillium species used in paper manufacturing, but recently it has been reported to cause invasive infection. To research the pathogenicity of the clinical Penicillium strain, we sequenced the genomes and transcriptomes of the clinical and environmental strains of P. capsulatum. Comparative analyses of these two P. capsulatum strains and close related strains belonging to Eurotiales were performed. The assembled genome sizes of P. capsulatum are approximately 34.4 Mbp in length and encode 11,080 predicted genes. The different isolates of P. capsulatum are highly similar, with the exception of several unique genes, INDELs or SNPs in the genes coding for glycosyl hydrolases, amino acid transporters and circumsporozoite protein. A phylogenomic analysis was performed based on the whole genome data of 38 strains belonging to Eurotiales. By comparing the whole genome sequences and the virulence-related genes from 20 important related species, including fungal pathogens and non-human pathogens belonging to Eurotiales, we found meaningful pathogenicity characteristics between P. capsulatum and its closely related species. Our research indicated that P. capsulatum may be a neglected opportunistic pathogen. This study is beneficial for mycologists, geneticists and epidemiologists to achieve a deeper understanding of the genetic basis of the role of P. capsulatum as a newly reported fungal pathogen. PMID:27761131

  20. DNA Copy Number Aberrations in Breast Cancer by Array Comparative Genomic Hybridization

    Institute of Scientific and Technical Information of China (English)

    Jian Li; Kai Wang; Shengting Li; Vera Timmermans-Wielenga; Fritz Rank; Carsten Wiuf; Xiuqing Zhang; Huanming Yang; Lars Bolund

    2009-01-01

    Array comparative genomic hybridization (CGH) has been popularly used for an-alyzing DNA copy number variations in diseases like cancer. In this study, we investigated 82 sporadic samples from 49 breast cancer patients using 1-Mb reso-lution bacterial artificial chromosome CGH arrays. A number of highly frequent genomic aberrations were discovered, which may act as "drivers" of tumor pro-gression. Meanwhile, the genomic profiles of four "normal" breast tissue samples taken at least 2 cm away from the primary tumor sites were also found to have some genomic aberrations that recurred with high frequency in the primary tu-mors, which may have important implications for clinical therapy. Additionally, we performed class comparison and class prediction for various clinicopathological pa-rameters, and a list of characteristic genomic aberrations associated with different clinicopathological phenotypes was compiled. Our study provides clues for further investigations of the underlying mechanisms of breast carcinogenesis.

  1. Comparative mitochondrial genomics toward exploring molecular markers in the medicinal fungus Cordyceps militaris.

    Science.gov (United States)

    Zhang, Shu; Hao, Ai-Jing; Zhao, Yu-Xiang; Zhang, Xiao-Yu; Zhang, Yong-Jie

    2017-01-10

    Cordyceps militaris is a fungus used for developing health food, but knowledge about its intraspecific differentiation is limited due to lack of efficient markers. Herein, we assembled the mitochondrial genomes of eight C. militaris strains and performed a comparative mitochondrial genomic analysis together with three previously reported mitochondrial genomes of the fungus. Sizes of the 11 mitochondrial genomes varied from 26.5 to 33.9 kb mainly due to variable intron contents (from two to eight introns per strain). Nucleotide variability varied according to different regions with non-coding regions showing higher variation frequency than coding regions. Recombination events were identified between some locus pairs but seemed not to contribute greatly to genetic variations of the fungus. Based on nucleotide diversity fluctuations across the alignment of all mitochondrial genomes, molecular markers with the potential to be used for future typing studies were determined.

  2. Comparative genomics of Synechococcus and proposal of the new genus Parasynechococcus

    Directory of Open Access Journals (Sweden)

    Felipe Coutinho

    2016-01-01

    Full Text Available Synechococcus is among the most important contributors to global primary productivity. The genomes of several strains of this taxon have been previously sequenced in an effort to understand the physiology and ecology of these highly diverse microorganisms. Here we present a comparative study of Synechococcus genomes. For that end, we developed GenTaxo, a program written in Perl to perform genomic taxonomy based on average nucleotide identity, average amino acid identity and dinucleotide signatures, which revealed that the analyzed strains are drastically distinct regarding their genomic content. Phylogenomic reconstruction indicated a division of Synechococcus in two clades (i.e. Synechococcus and the new genus Parasynechococcus, corroborating evidences that this is in fact a polyphyletic group. By clustering protein encoding genes into homologue groups we were able to trace the Pangenome and core genome of both marine and freshwater Synechococcus and determine the genotypic traits that differentiate these lineages.

  3. Comparative genomics of Synechococcus and proposal of the new genus Parasynechococcus.

    Science.gov (United States)

    Coutinho, Felipe; Tschoeke, Diogo Antonio; Thompson, Fabiano; Thompson, Cristiane

    2016-01-01

    Synechococcus is among the most important contributors to global primary productivity. The genomes of several strains of this taxon have been previously sequenced in an effort to understand the physiology and ecology of these highly diverse microorganisms. Here we present a comparative study of Synechococcus genomes. For that end, we developed GenTaxo, a program written in Perl to perform genomic taxonomy based on average nucleotide identity, average amino acid identity and dinucleotide signatures, which revealed that the analyzed strains are drastically distinct regarding their genomic content. Phylogenomic reconstruction indicated a division of Synechococcus in two clades (i.e. Synechococcus and the new genus Parasynechococcus), corroborating evidences that this is in fact a polyphyletic group. By clustering protein encoding genes into homologue groups we were able to trace the Pangenome and core genome of both marine and freshwater Synechococcus and determine the genotypic traits that differentiate these lineages.

  4. Comparative genomic assessment of Multi-Locus Sequence Typing: rapid accumulation of genomic heterogeneity among clonal isolates of Campylobacter jejuni

    Directory of Open Access Journals (Sweden)

    Nash John HE

    2008-08-01

    Full Text Available Abstract Background Multi-Locus Sequence Typing (MLST has emerged as a leading molecular typing method owing to its high ability to discriminate among bacterial isolates, the relative ease with which data acquisition and analysis can be standardized, and the high portability of the resulting sequence data. While MLST has been successfully applied to the study of the population structure for a number of different bacterial species, it has also provided compelling evidence for high rates of recombination in some species. We have analyzed a set of Campylobacter jejuni strains using MLST and Comparative Genomic Hybridization (CGH on a full-genome microarray in order to determine whether recombination and high levels of genomic mosaicism adversely affect the inference of strain relationships based on the analysis of a restricted number of genetic loci. Results Our results indicate that, in general, there is significant concordance between strain relationships established by MLST and those based on shared gene content as established by CGH. While MLST has significant predictive power with respect to overall genome similarity of isolates, we also found evidence for significant differences in genomic content among strains that would otherwise appear to be highly related based on their MLST profiles. Conclusion The extensive genomic mosaicism between closely related strains has important implications in the context of establishing strain to strain relationships because it suggests that the exact gene content of strains, and by extension their phenotype, is less likely to be "predicted" based on a small number of typing loci. This in turn suggests that a greater emphasis should be placed on analyzing genes of clinical interest as we forge ahead with the next generation of molecular typing methods.

  5. Genome-based comparative analyses of Antarctic and temperate species of Paenibacillus.

    Directory of Open Access Journals (Sweden)

    Melissa Dsouza

    Full Text Available Antarctic soils represent a unique environment characterised by extremes of temperature, salinity, elevated UV radiation, low nutrient and low water content. Despite the harshness of this environment, members of 15 bacterial phyla have been identified in soils of the Ross Sea Region (RSR. However, the survival mechanisms and ecological roles of these phyla are largely unknown. The aim of this study was to investigate whether strains of Paenibacillus darwinianus owe their resilience to substantial genomic changes. For this, genome-based comparative analyses were performed on three P. darwinianus strains, isolated from gamma-irradiated RSR soils, together with nine temperate, soil-dwelling Paenibacillus spp. The genome of each strain was sequenced to over 1,000-fold coverage, then assembled into contigs totalling approximately 3 Mbp per genome. Based on the occurrence of essential, single-copy genes, genome completeness was estimated at approximately 88%. Genome analysis revealed between 3,043-3,091 protein-coding sequences (CDSs, primarily associated with two-component systems, sigma factors, transporters, sporulation and genes induced by cold-shock, oxidative and osmotic stresses. These comparative analyses provide an insight into the metabolic potential of P. darwinianus, revealing potential adaptive mechanisms for survival in Antarctic soils. However, a large proportion of these mechanisms were also identified in temperate Paenibacillus spp., suggesting that these mechanisms are beneficial for growth and survival in a range of soil environments. These analyses have also revealed that the P. darwinianus genomes contain significantly fewer CDSs and have a lower paralogous content. Notwithstanding the incompleteness of the assemblies, the large differences in genome sizes, determined by the number of genes in paralogous clusters and the CDS content, are indicative of genome content scaling. Finally, these sequences are a resource for further

  6. CGHScan: finding variable regions using high-density microarray comparative genomic hybridization data

    Directory of Open Access Journals (Sweden)

    Rajashekara Gireesh

    2006-04-01

    Full Text Available Abstract Background Comparative genomic hybridization can rapidly identify chromosomal regions that vary between organisms and tissues. This technique has been applied to detecting differences between normal and cancerous tissues in eukaryotes as well as genomic variability in microbial strains and species. The density of oligonucleotide probes available on current microarray platforms is particularly well-suited for comparisons of organisms with smaller genomes like bacteria and yeast where an entire genome can be assayed on a single microarray with high resolution. Available methods for analyzing these experiments typically confine analyses to data from pre-defined annotated genome features, such as entire genes. Many of these methods are ill suited for datasets with the number of measurements typical of high-density microarrays. Results We present an algorithm for analyzing microarray hybridization data to aid identification of regions that vary between an unsequenced genome and a sequenced reference genome. The program, CGHScan, uses an iterative random walk approach integrating multi-layered significance testing to detect these regions from comparative genomic hybridization data. The algorithm tolerates a high level of noise in measurements of individual probe intensities and is relatively insensitive to the choice of method for normalizing probe intensity values and identifying probes that differ between samples. When applied to comparative genomic hybridization data from a published experiment, CGHScan identified eight of nine known deletions in a Brucella ovis strain as compared to Brucella melitensis. The same result was obtained using two different normalization methods and two different scores to classify data for individual probes as representing conserved or variable genomic regions. The undetected region is a small (58 base pair deletion that is below the resolution of CGHScan given the array design employed in the study

  7. Comparative Genomics of the Extreme Acidophile Acidithiobacillus thiooxidans Reveals Intraspecific Divergence and Niche Adaptation.

    Science.gov (United States)

    Zhang, Xian; Feng, Xue; Tao, Jiemeng; Ma, Liyuan; Xiao, Yunhua; Liang, Yili; Liu, Xueduan; Yin, Huaqun

    2016-01-01

    Acidithiobacillus thiooxidans known for its ubiquity in diverse acidic and sulfur-bearing environments worldwide was used as the research subject in this study. To explore the genomic fluidity and intraspecific diversity of Acidithiobacillus thiooxidans (A. thiooxidans) species, comparative genomics based on nine draft genomes was performed. Phylogenomic scrutiny provided first insights into the multiple groupings of these strains, suggesting that genetic diversity might be potentially correlated with their geographic distribution as well as geochemical conditions. While these strains shared a large number of common genes, they displayed differences in gene content. Functional assignment indicated that the core genome was essential for microbial basic activities such as energy acquisition and uptake of nutrients, whereas the accessory genome was thought to be involved in niche adaptation. Comprehensive analysis of their predicted central metabolism revealed that few differences were observed among these strains. Further analyses showed evidences of relevance between environmental conditions and genomic diversification. Furthermore, a diverse pool of mobile genetic elements including insertion sequences and genomic islands in all A. thiooxidans strains probably demonstrated the frequent genetic flow (such as lateral gene transfer) in the extremely acidic environments. From another perspective, these elements might endow A. thiooxidans species with capacities to withstand the chemical constraints of their natural habitats. Taken together, our findings bring some valuable data to better understand the genomic diversity and econiche adaptation within A. thiooxidans strains.

  8. Comparative Genomics of the Extreme Acidophile Acidithiobacillus thiooxidans Reveals Intraspecific Divergence and Niche Adaptation

    Directory of Open Access Journals (Sweden)

    Xian Zhang

    2016-08-01

    Full Text Available Acidithiobacillus thiooxidans known for its ubiquity in diverse acidic and sulfur-bearing environments worldwide was used as the research subject in this study. To explore the genomic fluidity and intraspecific diversity of Acidithiobacillus thiooxidans (A. thiooxidans species, comparative genomics based on nine draft genomes was performed. Phylogenomic scrutiny provided first insights into the multiple groupings of these strains, suggesting that genetic diversity might be potentially correlated with their geographic distribution as well as geochemical conditions. While these strains shared a large number of common genes, they displayed differences in gene content. Functional assignment indicated that the core genome was essential for microbial basic activities such as energy acquisition and uptake of nutrients, whereas the accessory genome was thought to be involved in niche adaptation. Comprehensive analysis of their predicted central metabolism revealed that few differences were observed among these strains. Further analyses showed evidences of relevance between environmental conditions and genomic diversification. Furthermore, a diverse pool of mobile genetic elements including insertion sequences and genomic islands in all A. thiooxidans strains probably demonstrated the frequent genetic flow (such as lateral gene transfer in the extremely acidic environments. From another perspective, these elements might endow A. thiooxidans species with capacities to withstand the chemical constraints of their natural habitats. Taken together, our findings bring some valuable data to better understand the genomic diversity and econiche adaptation within A. thiooxidans strains.

  9. Comparative genomics of an endophytic Pseudomonas putida isolated from mango orchard

    Directory of Open Access Journals (Sweden)

    Huma Asif

    Full Text Available Abstract We analyzed the genome sequence of an endophytic bacterial strain Pseudomonas putida TJI51 isolated from mango bark tissues. Next generation DNA sequencing and short read de novo assembly generated the 5,805,096 bp draft genome of P. putida TJI51. Out of 6,036 protein coding genes in P. putida TJI51 sequences, 4,367 (72% were annotated with functional specifications, while the remaining encoded hypothetical proteins. Comparative genome sequence analysis revealed that the P. putida TJI51genome contains several regions, not identified in so far sequenced P. putida genomes. Some of these regions were predicted to encode enzymes, including acetylornithine deacetylase, betaine aldehyde dehydrogenase, aldehyde dehydrogenase, benzoylformate decarboxylase, hydroxyacylglutathione hydrolase, and uroporphyrinogen decarboxylase. The genome of P. putida TJI51 contained three nonribosomal peptide synthetase gene clusters. Genome sequence analysis of P. putidaTJI51 identified this bacterium as an endophytic resident. The endophytic fitness might be linked with alginate, which facilitates bacterial colonization in plant tissues. Genome sequence analysis shed light on the presence of a diverse spectrum of metabolic activities and adaptation of this isolate to various niches.

  10. Comparative chloroplast genomics: analyses including new sequences from the angiosperms Nuphar advena and Ranunculus macranthus

    Directory of Open Access Journals (Sweden)

    Boore Jeffrey L

    2007-06-01

    Full Text Available Abstract Background The number of completely sequenced plastid genomes available is growing rapidly. This array of sequences presents new opportunities to perform comparative analyses. In comparative studies, it is often useful to compare across wide phylogenetic spans and, within angiosperms, to include representatives from basally diverging lineages such as the genomes reported here: Nuphar advena (from a basal-most lineage and Ranunculus macranthus (a basal eudicot. We report these two new plastid genome sequences and make comparisons (within angiosperms, seed plants, or all photosynthetic lineages to evaluate features such as the status of ycf15 and ycf68 as protein coding genes, the distribution of simple sequence repeats (SSRs and longer dispersed repeats (SDR, and patterns of nucleotide composition. Results The Nuphar [GenBank:NC_008788] and Ranunculus [GenBank:NC_008796] plastid genomes share characteristics of gene content and organization with many other chloroplast genomes. Like other plastid genomes, these genomes are A+T-rich, except for rRNA and tRNA genes. Detailed comparisons of Nuphar with Nymphaea, another Nymphaeaceae, show that more than two-thirds of these genomes exhibit at least 95% sequence identity and that most SSRs are shared. In broader comparisons, SSRs vary among genomes in terms of abundance and length and most contain repeat motifs based on A and T nucleotides. Conclusion SSR and SDR abundance varies by genome and, for SSRs, is proportional to genome size. Long SDRs are rare in the genomes assessed. SSRs occur less frequently than predicted and, although the majority of the repeat motifs do include A and T nucleotides, the A+T bias in SSRs is less than that predicted from the underlying genomic nucleotide composition. In codon usage third positions show an A+T bias, however variation in codon usage does not correlate with differences in A+T-richness. Thus, although plastome nucleotide composition shows "A

  11. Comparative assessment of genetic diversity in cytoplasmic and nuclear genome of upland cotton.

    Science.gov (United States)

    Egamberdiev, Sharof S; Saha, Sukumar; Salakhutdinov, Ilkhom; Jenkins, Johnie N; Deng, Dewayne; Y Abdurakhmonov, Ibrokhim

    2016-06-01

    The importance of the cytoplasmic genome for many economically important traits is well documented in several crop species, including cotton. There is no report on application of cotton chloroplast specific SSR markers as a diagnostic tool to study genetic diversity among improved Upland cotton lines. The complete plastome sequence information in GenBank provided us an opportunity to report on 17 chloroplast specific SSR markers using a cost-effective data mining strategy. Here we report the comparative analysis of genetic diversity among a set of 42 improved Upland cotton lines using SSR markers specific to chloroplast and nuclear genome, respectively. Our results revealed that low to moderate level of genetic diversity existed in both nuclear and cytoplasm genome among this set of cotton lines. However, the specific estimation suggested that genetic diversity is lower in cytoplasmic genome compared to the nuclear genome among this set of Upland cotton lines. In summary, this research is important from several perspectives. We detected a set of cytoplasm genome specific SSR primer pairs by using a cost-effective data mining strategy. We reported for the first time the genetic diversity in the cytoplasmic genome within a set of improved Upland cotton accessions. Results revealed that the genetic diversity in cytoplasmic genome is narrow, compared to the nuclear genome within this set of Upland cotton accessions. Our results suggested that most of these polymorphic chloroplast SSRs would be a valuable complementary tool in addition to the nuclear SSR in the study of evolution, gene flow and genetic diversity in Upland cotton.

  12. Comparative analysis of microsatellites in chloroplast genomes of lower and higher plants.

    Science.gov (United States)

    George, Biju; Bhatt, Bhavin S; Awasthi, Mayur; George, Binu; Singh, Achuit K

    2015-11-01

    Microsatellites, or simple sequence repeats (SSRs), contain repetitive DNA sequence where tandem repeats of one to six base pairs are present number of times. Chloroplast genome sequences have been  shown to possess extensive variations in the length, number and distribution of SSRs. However, a comparative analysis of chloroplast microsatellites is not available. Considering their potential importance in generating genomic diversity, we have systematically analysed the abundance and distribution of simple and compound microsatellites in 164 sequenced chloroplast genomes from wide range of plants. The key findings of these studies are (1) a large number of mononucleotide repeats as compared to SSR(2-6)(di-, tri-, tetra-, penta-, hexanucleotide repeats) are present in all chloroplast genomes investigated, (2) lower plants such as algae show wide variation in relative abundance, density and distribution of microsatellite repeats as compared to flowering plants, (3) longer SSRs are excluded from coding regions of most chloroplast genomes, (4) GC content has a weak influence on number, relative abundance and relative density of mononucleotide as well as SSR(2-6). However, GC content strongly showed negative correlation with relative density (R (2) = 0.5, P plants possesses relatively more genomic diversity compared to higher plants.

  13. New families of human regulatory RNA structures identified by comparative analysis of vertebrate genomes

    DEFF Research Database (Denmark)

    Parker, Brian John; Moltke, Ida; Roth, Adam Anders Edvin;

    2011-01-01

    involving six long hairpins in the 3'-UTR of MAT2A, a key metabolic gene that produces the primary human methyl donor S-adenosylmethionine; the other involving a tRNA-like structure in the intron of the tRNA maturation gene POP1. We experimentally validate the predicted MAT2A structures. Finally, we...... a comparative method, EvoFam, for genome-wide identification of families of regulatory RNA structures, based on primary sequence and secondary structure similarity. We apply EvoFam to a 41-way genomic vertebrate alignment. Genome-wide, we identify 220 human, high-confidence families outside protein...

  14. Comparative Analysis on Genomes from Oryza alta and Oryza latifolia by C0t-1 DNA

    Institute of Scientific and Technical Information of China (English)

    WANG De-bin; WANG Yang; WU Qi; ZHAO Hou-ming; LI Gang; QIN Rui; WANG Chun-tai; LIU Hong

    2010-01-01

    In order to reveal the origin and evolutionary relationship between two CCDD genome species, Oryza alta and Oryza latifolia, fluorescence in situ hybridization (FISH) was adopted to analyze the genomes of the two species with C0t-1 DNA from O. alta as a probe. Karyotype was also comparatively analyzed between O. alta and O. latifolia based on their similar band patterns of the hybridization signals. There were a high homology and close relationship between O. alta and O. latifolia, however, the distinction between the hybridization signals was also clear. C0t-1 DNA was proved to be species- and genome type-specific. It is suggested that C0t-1 DNA-FISH could be more efficient to analyze the genomic relationship between different species. According to the comparative analysis of highly and moderately repetitive DNA sequences between the two allotetraploidy species, O. alta and O. latifolia, the possible origin and evolutionary mechanism of allotetraploidy of Oryza were discussed.

  15. Comparative genomics of human stem cell factor (SCF

    Directory of Open Access Journals (Sweden)

    Moein Dehbashi

    2017-03-01

    Full Text Available Stem cell factor (SCF is a critical protein with key roles in the cell such as hematopoiesis, gametogenesis and melanogenesis. In the present study a comparative analysis on nucleotide sequences of SCF was performed in Humanoids using bioinformatics tools including NCBI-BLAST, MEGA6, and JBrowse. Our analysis of nucleotide sequences to find closely evolved organisms with high similarity by NCBI-BLAST tools and MEGA6 showed that human and Chimpanzee (Pan troglodytes were placed into the same cluster. By using JBrowse, we found that SCF in Neanderthal had a single copy number similar to modern human and partly conserved nucleotide sequences. Together, the results approved the gene flow and genetics similarity of SCF among human and P. troglodytes. This may suggest that during evolution, SCF gene transferred partly intact either on the basis of sequence or function from the same ancestors to P. troglodytes, the ancient human like Neanderthal, and then to the modern human.

  16. Characterization of genomic alterations in radiation-associated breast cancer among childhood cancer survivors, using comparative genomic hybridization (CGH arrays.

    Directory of Open Access Journals (Sweden)

    Xiaohong R Yang

    Full Text Available Ionizing radiation is an established risk factor for breast cancer. Epidemiologic studies of radiation-exposed cohorts have been primarily descriptive; molecular events responsible for the development of radiation-associated breast cancer have not been elucidated. In this study, we used array comparative genomic hybridization (array-CGH to characterize genome-wide copy number changes in breast tumors collected in the Childhood Cancer Survivor Study (CCSS. Array-CGH data were obtained from 32 cases who developed a second primary breast cancer following chest irradiation at early ages for the treatment of their first cancers, mostly Hodgkin lymphoma. The majority of these cases developed breast cancer before age 45 (91%, n = 29, had invasive ductal tumors (81%, n = 26, estrogen receptor (ER-positive staining (68%, n = 19 out of 28, and high proliferation as indicated by high Ki-67 staining (77%, n = 17 out of 22. Genomic regions with low-copy number gains and losses and high-level amplifications were similar to what has been reported in sporadic breast tumors, however, the frequency of amplifications of the 17q12 region containing human epidermal growth factor receptor 2 (HER2 was much higher among CCSS cases (38%, n = 12. Our findings suggest that second primary breast cancers in CCSS were enriched for an "amplifier" genomic subgroup with highly proliferative breast tumors. Future investigation in a larger irradiated cohort will be needed to confirm our findings.

  17. A Whole Genome Pairwise Comparative and Functional Analysis of Geobacter sulfurreducens PCA

    OpenAIRE

    2013-01-01

    Geobacter species are involved in electricity production, bioremediations, and various environmental friendly activities. Whole genome comparative analyses of Geobacter sulfurreducens PCA, Geobacter bemidjiensis Bem, Geobacter sp. FRC-32, Geobacter lovleyi SZ, Geobacter sp. M21, Geobacter metallireducens GS-15, Geobacter uraniireducens Rf4 have been made to find out similarities and dissimilarities among them. For whole genome comparison of Geobacter species, an in-house tool, Geobacter Compa...

  18. Complete Chloroplast Genome Sequence of Omani Lime (Citrus aurantiifolia) and Comparative Analysis within the Rosids

    OpenAIRE

    Huei-Jiun Su; Hogenhout, Saskia A.; Al-Sadi, Abdullah M.; Chih-Horng Kuo

    2014-01-01

    The genus Citrus contains many economically important fruits that are grown worldwide for their high nutritional and medicinal value. Due to frequent hybridizations among species and cultivars, the exact number of natural species and the taxonomic relationships within this genus are unclear. To compare the differences between the Citrus chloroplast genomes and to develop useful genetic markers, we used a reference-assisted approach to assemble the complete chloroplast genome of Omani lime (C....

  19. Comparative analysis of Salmonella genomes identifies a metabolic network for escalating growth in the inflamed gut.

    Science.gov (United States)

    Nuccio, Sean-Paul; Bäumler, Andreas J

    2014-03-18

    The Salmonella genus comprises a group of pathogens associated with illnesses ranging from gastroenteritis to typhoid fever. We performed an in silico analysis of comparatively reannotated Salmonella genomes to identify genomic signatures indicative of disease potential. By removing numerous annotation inconsistencies and inaccuracies, the process of reannotation identified a network of 469 genes involved in central anaerobic metabolism, which was intact in genomes of gastrointestinal pathogens but degrading in genomes of extraintestinal pathogens. This large network contained pathways that enable gastrointestinal pathogens to utilize inflammation-derived nutrients as well as many of the biochemical reactions used for the enrichment and biochemical discrimination of Salmonella serovars. Thus, comparative genome analysis identifies a metabolic network that provides clues about the strategies for nutrient acquisition and utilization that are characteristic of gastrointestinal pathogens. IMPORTANCE While some Salmonella serovars cause infections that remain localized to the gut, others disseminate throughout the body. Here, we compared Salmonella genomes to identify characteristics that distinguish gastrointestinal from extraintestinal pathogens. We identified a large metabolic network that is functional in gastrointestinal pathogens but decaying in extraintestinal pathogens. While taxonomists have used traits from this network empirically for many decades for the enrichment and biochemical discrimination of Salmonella serovars, our findings suggest that it is part of a "business plan" for growth in the inflamed gastrointestinal tract. By identifying a large metabolic network characteristic of Salmonella serovars associated with gastroenteritis, our in silico analysis provides a blueprint for potential strategies to utilize inflammation-derived nutrients and edge out competing gut microbes.

  20. Comparative anatomy of marmoset and mouse cortex from genomic expression.

    Science.gov (United States)

    Mashiko, Hiromi; Yoshida, Aya C; Kikuchi, Satomi S; Niimi, Kimie; Takahashi, Eiki; Aruga, Jun; Okano, Hideyuki; Shimogori, Tomomi

    2012-04-11

    Advances in mouse neural circuit genetics, brain atlases, and behavioral assays provide a powerful system for modeling the genetic basis of cognition and psychiatric disease. However, a critical limitation of this approach is how to achieve concordance of mouse neurobiology with the ultimate goal of understanding the human brain. Previously, the common marmoset has shown promise as a genetic model system toward the linking of mouse and human studies. However, the advent of marmoset transgenic approaches will require an understanding of developmental principles in marmoset compared to mouse. In this study, we used gene expression analysis in marmoset brain to pose a series of fundamental questions on cortical development and evolution for direct comparison to existing mouse brain atlas expression data. Most genes showed reliable conservation of expression between marmoset and mouse. However, certain markers had strikingly divergent expression patterns. The lateral geniculate nucleus and pulvinar in the thalamus showed diversification of genetic organization between marmoset and mouse, suggesting they share some similarity. In contrast, gene expression patterns in early visual cortical areas showed marmoset-specific expression. In prefrontal cortex, some markers labeled architectonic areas and layers distinct between mouse and marmoset. Core hippocampus was conserved, while afferent areas showed divergence. Together, these results indicate that existing cortical areas are genetically conserved between marmoset and mouse, while differences in areal parcellation, afferent diversification, and layer complexity are associated with specific genes. Collectively, we propose that gene expression patterns in marmoset brain reveal important clues to the principles underlying the molecular evolution of cortical and cognitive expansion.

  1. The Methanosarcina barkeri genome: comparative analysis withMethanosarcina acetivorans and Methanosarcina mazei reveals extensiverearrangement within methanosarcinal genomes

    Energy Technology Data Exchange (ETDEWEB)

    Maeder, Dennis L.; Anderson, Iain; Brettin, Thomas S.; Bruce,David C.; Gilna, Paul; Han, Cliff S.; Lapidus, Alla; Metcalf, William W.; Saunders, Elizabeth; Tapia, Roxanne; Sowers, Kevin R.

    2006-05-19

    We report here a comparative analysis of the genome sequence of Methanosarcina barkeri with those of Methanosarcina acetivorans and Methanosarcina mazei. All three genomes share a conserved double origin of replication and many gene clusters. M. barkeri is distinguished by having an organization that is well conserved with respect to the other Methanosarcinae in the region proximal to the origin of replication with interspecies gene similarities as high as 95%. However it is disordered and marked by increased transposase frequency and decreased gene synteny and gene density in the proximal semi-genome. Of the 3680 open reading frames in M. barkeri, 678 had paralogs with better than 80% similarity to both M. acetivorans and M. mazei while 128 nonhypothetical orfs were unique (non-paralogous) amongst these species including a complete formate dehydrogenase operon, two genes required for N-acetylmuramic acid synthesis, a 14 gene gas vesicle cluster and a bacterial P450-specific ferredoxin reductase cluster not previously observed or characterized in this genus. A cryptic 36 kbp plasmid sequence was detected in M. barkeri that contains an orc1 gene flanked by a presumptive origin of replication consisting of 38 tandem repeats of a 143 nt motif. Three-way comparison of these genomes reveals differing mechanisms for the accrual of changes. Elongation of the large M. acetivorans is the result of multiple gene-scale insertions and duplications uniformly distributed in that genome, while M. barkeri is characterized by localized inversions associated with the loss of gene content. In contrast, the relatively short M. mazei most closely approximates the ancestral organizational state.

  2. Genomic organization, annotation, and ligand-receptor inferences of chicken chemokines and chemokine receptor genes based on comparative genomics

    Directory of Open Access Journals (Sweden)

    Sze Sing-Hoi

    2005-03-01

    Full Text Available Abstract Background Chemokines and their receptors play important roles in host defense, organogenesis, hematopoiesis, and neuronal communication. Forty-two chemokines and 19 cognate receptors have been found in the human genome. Prior to this report, only 11 chicken chemokines and 7 receptors had been reported. The objectives of this study were to systematically identify chicken chemokines and their cognate receptor genes in the chicken genome and to annotate these genes and ligand-receptor binding by a comparative genomics approach. Results Twenty-three chemokine and 14 chemokine receptor genes were identified in the chicken genome. All of the chicken chemokines contained a conserved CC, CXC, CX3C, or XC motif, whereas all the chemokine receptors had seven conserved transmembrane helices, four extracellular domains with a conserved cysteine, and a conserved DRYLAIV sequence in the second intracellular domain. The number of coding exons in these genes and the syntenies are highly conserved between human, mouse, and chicken although the amino acid sequence homologies are generally low between mammalian and chicken chemokines. Chicken genes were named with the systematic nomenclature used in humans and mice based on phylogeny, synteny, and sequence homology. Conclusion The independent nomenclature of chicken chemokines and chemokine receptors suggests that the chicken may have ligand-receptor pairings similar to mammals. All identified chicken chemokines and their cognate receptors were identified in the chicken genome except CCR9, whose ligand was not identified in this study. The organization of these genes suggests that there were a substantial number of these genes present before divergence between aves and mammals and more gene duplications of CC, CXC, CCR, and CXCR subfamilies in mammals than in aves after the divergence.

  3. Comparative genomics and transcriptomics of lineages I, II, and III strains of Listeria monocytogenes

    Directory of Open Access Journals (Sweden)

    Hain Torsten

    2012-04-01

    Full Text Available Abstract Background Listeria monocytogenes is a food-borne pathogen that causes infections with a high-mortality rate and has served as an invaluable model for intracellular parasitism. Here, we report complete genome sequences for two L. monocytogenes strains belonging to serotype 4a (L99 and 4b (CLIP80459, and transcriptomes of representative strains from lineages I, II, and III, thereby permitting in-depth comparison of genome- and transcriptome -based data from three lineages of L. monocytogenes. Lineage III, represented by the 4a L99 genome is known to contain strains less virulent for humans. Results The genome analysis of the weakly pathogenic L99 serotype 4a provides extensive evidence of virulence gene decay, including loss of several important surface proteins. The 4b CLIP80459 genome, unlike the previously sequenced 4b F2365 genome harbours an intact inlB invasion gene. These lineage I strains are characterized by the lack of prophage genes, as they share only a single prophage locus with other L. monocytogenes genomes 1/2a EGD-e and 4a L99. Comparative transcriptome analysis during intracellular growth uncovered adaptive expression level differences in lineages I, II and III of Listeria, notable amongst which was a strong intracellular induction of flagellar genes in strain 4a L99 compared to the other lineages. Furthermore, extensive differences between strains are manifest at levels of metabolic flux control and phosphorylated sugar uptake. Intriguingly, prophage gene expression was found to be a hallmark of intracellular gene expression. Deletion mutants in the single shared prophage locus of lineage II strain EGD-e 1/2a, the lma operon, revealed severe attenuation of virulence in a murine infection model. Conclusion Comparative genomics and transcriptome analysis of L. monocytogenes strains from three lineages implicate prophage genes in intracellular adaptation and indicate that gene loss and decay may have led to the emergence

  4. Phage morphology recapitulates phylogeny: the comparative genomics of a new group of myoviruses.

    Directory of Open Access Journals (Sweden)

    André M Comeau

    Full Text Available Among dsDNA tailed bacteriophages (Caudovirales, members of the Myoviridae family have the most sophisticated virion design that includes a complex contractile tail structure. The Myoviridae generally have larger genomes than the other phage families. Relatively few "dwarf" myoviruses, those with a genome size of less than 50 kb such as those of the Mu group, have been analyzed in extenso. Here we report on the genome sequencing and morphological characterization of a new group of such phages that infect a diverse range of Proteobacteria, namely Aeromonas salmonicida phage 56, Vibrio cholerae phages 138 and CP-T1, Bdellovibrio phage φ1422, and Pectobacterium carotovorum phage ZF40. This group of dwarf myoviruses shares an identical virion morphology, characterized by usually short contractile tails, and have genome sizes of approximately 45 kb. Although their genome sequences are variable in their lysogeny, replication, and host adaption modules, presumably reflecting differing lifestyles and hosts, their structural and morphogenesis modules have been evolutionarily constrained by their virion morphology. Comparative genomic analysis reveals that these phages, along with related prophage genomes, form a new coherent group within the Myoviridae. The results presented in this communication support the hypothesis that the diversity of phages may be more structured than generally believed and that the innumerable phages in the biosphere all belong to discrete lineages or families.

  5. MultiMetEval : Comparative and Multi-Objective Analysis of Genome-Scale Metabolic Models

    NARCIS (Netherlands)

    Zakrzewski, Piotr; Medema, Marnix H.; Gevorgyan, Albert; Kierzek, Andrzej M.; Breitling, Rainer; Takano, Eriko; Fong, Stephen S.

    2012-01-01

    Comparative metabolic modelling is emerging as a novel field, supported by the development of reliable and standardized approaches for constructing genome-scale metabolic models in high throughput. New software solutions are needed to allow efficient comparative analysis of multiple models in the co

  6. The Genome of Nosema sp. Isolate YNPr: A Comparative Analysis of Genome Evolution within the Nosema/Vairimorpha Clade

    Science.gov (United States)

    Ma, Zhenggang; Li, Tian; Zhang, Xiaoyan; Debrunner-Vossbrinck, Bettina A.; Zhou, Zeyang; Vossbrinck, Charles R.

    2016-01-01

    The microsporidian parasite designated here as Nosema sp. Isolate YNPr was isolated from the cabbage butterfly Pieris rapae collected in Honghe Prefecture, Yunnan Province, China. The genome was sequenced by Illumina sequencing and compared to those of two related members of the Nosema/Vairimorpha clade, Nosema ceranae and Nosema apis. Based upon assembly statistics, the Nosema sp. YNPr genome is 3.36 x 106bp with a G+C content of 23.18% and 2,075 protein coding sequences. An “ACCCTT” motif is present approximately 50-bp upstream of the start codon, as reported from other members of the clade and from Encephalitozoon cuniculi, a sister taxon. Comparative small subunit ribosomal DNA (SSU rDNA) analysis as well as genome-wide phylogenetic analysis confirms a closer relationship between N. ceranae and Nosema sp. YNPr than between the two honeybee parasites N. ceranae and N. apis. The more closely related N. ceranae and Nosema sp. YNPr show similarities in a number of structural characteristics such as gene synteny, gene length, gene number, transposon composition and gene reduction. Based on transposable element content of the assemblies, the transposon content of Nosema sp. YNPr is 4.8%, that of N. ceranae is 3.7%, and that of N. apis is 2.5%, with large differences in the types of transposons present among these 3 species. Gene function annotation indicates that the number of genes participating in most metabolic activities is similar in all three species. However, the number of genes in the transcription, general function, and cysteine protease categories is greater in N. apis than in the other two species. Our studies further characterize the evolution of the Nosema/Vairimorpha clade of microsporidia. These organisms maintain variable but very reduced genomes. We are interested in understanding the effects of genetic drift versus natural selection on genome size in the microsporidia and in developing a testable hypothesis for further studies on the genomic

  7. Comparative genomics of the bacterial genus Streptococcus illuminates evolutionary implications of species groups.

    Directory of Open Access Journals (Sweden)

    Xiao-Yang Gao

    Full Text Available Members of the genus Streptococcus within the phylum Firmicutes are among the most diverse and significant zoonotic pathogens. This genus has gone through considerable taxonomic revision due to increasing improvements of chemotaxonomic approaches, DNA hybridization and 16S rRNA gene sequencing. It is proposed to place the majority of streptococci into "species groups". However, the evolutionary implications of species groups are not clear presently. We use comparative genomic approaches to yield a better understanding of the evolution of Streptococcus through genome dynamics, population structure, phylogenies and virulence factor distribution of species groups. Genome dynamics analyses indicate that the pan-genome size increases with the addition of newly sequenced strains, while the core genome size decreases with sequential addition at the genus level and species group level. Population structure analysis reveals two distinct lineages, one including Pyogenic, Bovis, Mutans and Salivarius groups, and the other including Mitis, Anginosus and Unknown groups. Phylogenetic dendrograms show that species within the same species group cluster together, and infer two main clades in accordance with population structure analysis. Distribution of streptococcal virulence factors has no obvious patterns among the species groups; however, the evolution of some common virulence factors is congruous with the evolution of species groups, according to phylogenetic inference. We suggest that the proposed streptococcal species groups are reasonable from the viewpoints of comparative genomics; evolution of the genus is congruent with the individual evolutionary trajectories of different species groups.

  8. Comparative genomics of rhizobia nodulating soybean suggests extensive recruitment of lineage-specific genes in adaptations.

    Science.gov (United States)

    Tian, Chang Fu; Zhou, Yuan Jie; Zhang, Yan Ming; Li, Qin Qin; Zhang, Yun Zeng; Li, Dong Fang; Wang, Shuang; Wang, Jun; Gilbert, Luz B; Li, Ying Rui; Chen, Wen Xin

    2012-05-29

    The rhizobium-legume symbiosis has been widely studied as the model of mutualistic evolution and the essential component of sustainable agriculture. Extensive genetic and recent genomic studies have led to the hypothesis that many distinct strategies, regardless of rhizobial phylogeny, contributed to the varied rhizobium-legume symbiosis. We sequenced 26 genomes of Sinorhizobium and Bradyrhizobium nodulating soybean to test this hypothesis. The Bradyrhizobium core genome is disproportionally enriched in lipid and secondary metabolism, whereas several gene clusters known to be involved in osmoprotection and adaptation to alkaline pH are specific to the Sinorhizobium core genome. These features are consistent with biogeographic patterns of these bacteria. Surprisingly, no genes are specifically shared by these soybean microsymbionts compared with other legume microsymbionts. On the other hand, phyletic patterns of 561 known symbiosis genes of rhizobia reflected the species phylogeny of these soybean microsymbionts and other rhizobia. Similar analyses with 887 known functional genes or the whole pan genome of rhizobia revealed that only the phyletic distribution of functional genes was consistent with the species tree of rhizobia. Further evolutionary genetics revealed that recombination dominated the evolution of core genome. Taken together, our results suggested that faithfully vertical genes were rare compared with those with history of recombination including lateral gene transfer, although rhizobial adaptations to symbiotic interactions and other environmental conditions extensively recruited lineage-specific shell genes under direct or indirect control through the speciation process.

  9. Comparative genomics of Japanese Erwinia pyrifoliae strain Ejp617 with closely related erwinias.

    Science.gov (United States)

    Thapa, Shree P; Park, Duck H; Kim, Won S; Choi, Beom S; Lim, Jong S; Choi, Ik Y; Hur, Jang H; Lim, Chun K

    2013-02-01

    Japanese Erwinia pyrifoliae strains cause bacterial shoot blight of pear (BSBP) in Japan. The genetics of Japanese Erwinia remains largely unknown relative to the abundant genomic information available for other Erwinia strains. We compared the genome of Japanese and Korean E. pyrifoliae strains along with those of E. amylovora and E. tasmaniensis. Comparisons with the Korean E. pyrifoliae strain revealed numerous gene insertions/deletions, rearrangements, and inversions in the central regions of the chromosomes. Approximately 80% (2843) of coding DNA sequences (CDSs) are shared by these two genomes which represent about three-quarters of the genome, and there are about 20% unique CDSs. Comparative analysis with closely related erwinias showed that 1942 (more than 50%) core open reading frames (ORF) are shared by all these strains. In addition to two type III secretion systems (hrp/dsp and inv/spa), the genome of Ejp617 encodes numerous virulence factors, including a type VI secretion system, an exopolysaccharide synthesis cluster, and another protein secretion system present in plant pathogenic Erwinia strains. The availability of whole genome sequence should provide a resource to further improve the understanding of pathogenesis in Japanese E. pyrifoliae Ejp617 and to facilitate evolutionary studies among the species of the genus Erwinia.

  10. Genetic Characterization and Comparative Genome Analysis of Brucella melitensis Isolates from India

    Directory of Open Access Journals (Sweden)

    Sarwar Azam

    2016-01-01

    Full Text Available Brucellosis is the most frequent zoonotic disease worldwide, with over 500,000 new human infections every year. Brucella melitensis, the most virulent species in humans, primarily affects goats and the zoonotic transmission occurs by ingestion of unpasteurized milk products or through direct contact with fetal tissues. Brucellosis is endemic in India but no information is available on population structure and genetic diversity of Brucella spp. in India. We performed multilocus sequence typing of four B. melitensis strains isolated from naturally infected goats from India. For more detailed genetic characterization, we carried out whole genome sequencing and comparative genome analysis of one of the B. melitensis isolates, Bm IND1. Genome analysis identified 141 unique SNPs, 78 VNTRs, 51 Indels, and 2 putative prophage integrations in the Bm IND1 genome. Our data may help to develop improved epidemiological typing tools and efficient preventive strategies to control brucellosis.

  11. Genetic Characterization and Comparative Genome Analysis of Brucella melitensis Isolates from India

    Science.gov (United States)

    Azam, Sarwar; Rao, Sashi Bhushan; Jakka, Padmaja; NarasimhaRao, Veera; Bhargavi, Bindu; Gupta, Vivek Kumar

    2016-01-01

    Brucellosis is the most frequent zoonotic disease worldwide, with over 500,000 new human infections every year. Brucella melitensis, the most virulent species in humans, primarily affects goats and the zoonotic transmission occurs by ingestion of unpasteurized milk products or through direct contact with fetal tissues. Brucellosis is endemic in India but no information is available on population structure and genetic diversity of Brucella spp. in India. We performed multilocus sequence typing of four B. melitensis strains isolated from naturally infected goats from India. For more detailed genetic characterization, we carried out whole genome sequencing and comparative genome analysis of one of the B. melitensis isolates, Bm IND1. Genome analysis identified 141 unique SNPs, 78 VNTRs, 51 Indels, and 2 putative prophage integrations in the Bm IND1 genome. Our data may help to develop improved epidemiological typing tools and efficient preventive strategies to control brucellosis. PMID:27525259

  12. Comparative genomic analysis of the thermophilic biomass-degrading fungi Myceliophthora thermophila and Thielavia terrestris.

    Science.gov (United States)

    Berka, Randy M; Grigoriev, Igor V; Otillar, Robert; Salamov, Asaf; Grimwood, Jane; Reid, Ian; Ishmael, Nadeeza; John, Tricia; Darmond, Corinne; Moisan, Marie-Claude; Henrissat, Bernard; Coutinho, Pedro M; Lombard, Vincent; Natvig, Donald O; Lindquist, Erika; Schmutz, Jeremy; Lucas, Susan; Harris, Paul; Powlowski, Justin; Bellemare, Annie; Taylor, David; Butler, Gregory; de Vries, Ronald P; Allijn, Iris E; van den Brink, Joost; Ushinsky, Sophia; Storms, Reginald; Powell, Amy J; Paulsen, Ian T; Elbourne, Liam D H; Baker, Scott E; Magnuson, Jon; Laboissiere, Sylvie; Clutterbuck, A John; Martinez, Diego; Wogulis, Mark; de Leon, Alfredo Lopez; Rey, Michael W; Tsang, Adrian

    2011-10-02

    Thermostable enzymes and thermophilic cell factories may afford economic advantages in the production of many chemicals and biomass-based fuels. Here we describe and compare the genomes of two thermophilic fungi, Myceliophthora thermophila and Thielavia terrestris. To our knowledge, these genomes are the first described for thermophilic eukaryotes and the first complete telomere-to-telomere genomes for filamentous fungi. Genome analyses and experimental data suggest that both thermophiles are capable of hydrolyzing all major polysaccharides found in biomass. Examination of transcriptome data and secreted proteins suggests that the two fungi use shared approaches in the hydrolysis of cellulose and xylan but distinct mechanisms in pectin degradation. Characterization of the biomass-hydrolyzing activity of recombinant enzymes suggests that these organisms are highly efficient in biomass decomposition at both moderate and high temperatures. Furthermore, we present evidence suggesting that aside from representing a potential reservoir of thermostable enzymes, thermophilic fungi are amenable to manipulation using classical and molecular genetics.

  13. Genetic Characterization and Comparative Genome Analysis of Brucella melitensis Isolates from India.

    Science.gov (United States)

    Azam, Sarwar; Rao, Sashi Bhushan; Jakka, Padmaja; NarasimhaRao, Veera; Bhargavi, Bindu; Gupta, Vivek Kumar; Radhakrishnan, Girish

    2016-01-01

    Brucellosis is the most frequent zoonotic disease worldwide, with over 500,000 new human infections every year. Brucella melitensis, the most virulent species in humans, primarily affects goats and the zoonotic transmission occurs by ingestion of unpasteurized milk products or through direct contact with fetal tissues. Brucellosis is endemic in India but no information is available on population structure and genetic diversity of Brucella spp. in India. We performed multilocus sequence typing of four B. melitensis strains isolated from naturally infected goats from India. For more detailed genetic characterization, we carried out whole genome sequencing and comparative genome analysis of one of the B. melitensis isolates, Bm IND1. Genome analysis identified 141 unique SNPs, 78 VNTRs, 51 Indels, and 2 putative prophage integrations in the Bm IND1 genome. Our data may help to develop improved epidemiological typing tools and efficient preventive strategies to control brucellosis.

  14. Comparative genomic analysis of the thermophilic biomass-degrading fungi Myceliophthora thermophila and Thielavia terrestris

    Energy Technology Data Exchange (ETDEWEB)

    Berka, Randy M.; Grigoriev, Igor V.; Otillar, Robert; Salamov, Asaf; Grimwood, Jane; Reid, Ian; Ishmael, Nadeeza; John, Tricia; Darmond, Corinne; Moisan, Marie-Claude; Henrissat, Bernard; Coutinho, Pedro M.; Lombard, Vincent; Natvig, Donald O.; Lindquist, Erika; Schmutz, Jeremy; Lucas, Susan; Harris, Paul; Powlowski, Justin; Bellemare, Annie; Taylor, David; Butler, Gregory; de Vries, Ronald P.; Allijn, Iris E.; van den Brink, Joost; Ushinsky, Sophia; Storms, Reginald; Powell, Amy J.; Paulsen, Ian T.; Elbourne, Liam D. H.; Baker, Scott E.; Magnuson, Jon; LaBoissiere, Sylvie; Clutterbuck, A. John; Martinez, Diego; Wogulis, Mark; de Leon, Alfredo Lopez; Rey, Michael W.; Tsang, Adrian

    2011-10-02

    Thermostable enzymes and thermophilic cell factories may afford economic advantages in the production of many chemicals and biomass-based fuels. Here we describe and compare the genomes of two thermophilic fungi, Myceliophthora thermophila and Thielavia terrestris. To our knowledge, these genomes are the first described for thermophilic eukaryotes and the first complete telomere-to-telomere genomes for filamentous fungi. Genome analyses and experimental data suggest that both thermophiles are capable of hydrolyzing all major polysaccharides found in biomass. Examination of transcriptome data and secreted proteins suggests that the two fungi use shared approaches in the hydrolysis of cellulose and xylan but distinct mechanisms in pectin degradation. Characterization of the biomass-hydrolyzing activity of recombinant enzymes suggests that these organisms are highly efficient in biomass decomposition at both moderate and high temperatures. Furthermore, we present evidence suggesting that aside from representing a potential reservoir of thermostable enzymes, thermophilic fungi are amenable to manipulation using classical and molecular genetics.

  15. Comparative Genome Analyses of Vibrio anguillarum Strains Reveal a Link with Pathogenicity Traits

    DEFF Research Database (Denmark)

    Castillo, Daniel; D'Alvise, Paul; Xu, Ruiqi

    2017-01-01

    Vibrio anguillarum is a marine bacterium that can cause vibriosis in many fish and shellfish species, leading to high mortalities and economic losses in aquaculture. Although putative virulence factors have been identified, the mechanism of pathogenesis of V. anguillarum is not fully understood....... anguillarum strains that were medium to nonvirulent had a high degree of genomic homogeneity. Finally, we found that a phylogeny based on the core genomes clustered the strains with moderate to no virulence, while six out of nine high-virulence strains represented phylogenetically separate clusters. Hence, we suggest...... be a powerful tool to discover acquisition of mobile genetic elements related to virulence. Here, we compared 28 V. anguillarum strains that differed in virulence in fish larval models. By pan-genome analyses, we found that six of nine highly virulent strains had a unique core and accessory genome. In contrast...

  16. Comparative genomic analysis of the thermophilic biomass-degrading fungi Myceliophthora thermophila and Thielavia terrestris

    Energy Technology Data Exchange (ETDEWEB)

    Berka, Randy M.; Grigoriev, Igor V.; Otillar, Robert; Salamov, Asaf; Grimwood, Jane; Reid, Ian; Ishmael, Nadeeza; John, Tricia; Darmond, Corinne; Moisan, Marie-Claude; Henrissat, Bernard; Coutinho, Pedro M.; Lombard, Vincent; Natvig, Donald O.; Lindquist, Erika; Schmutz, Jeremy; Lucas, Susan; Harris, Paul; Powlowski, Justin; Bellemare, Annie; Taylor, David; Butler, Gregory; de Vries, Ronald P.; Allijn, Iris E.; van den Brink, Joost; Ushinsky, Sophia; Storms, Reginald; Powell, Amy J.; Paulsen, Ian T.; Elbourne, Liam D. H.; Baker, Scott. E.; Magnuson, Jon; LaBoissiere, Sylvie; Clutterbuck, A. John; Martinez, Diego; Wogulis, Mark; Lopez de Leon, Alfredo; Rey, Michael W.; Tsang, Adrian

    2011-05-16

    Thermostable enzymes and thermophilic cell factories may afford economic advantages in the production of many chemicals and biomass-based fuels. Here we describe and compare the genomes of two thermophilic fungi, Myceliophthora thermophila and Thielavia terrestris. To our knowledge, these genomes are the first described for thermophilic eukaryotes and the first complete telomere-to-telomere genomes for filamentous fungi. Genome analyses and experimental data suggest that both thermophiles are capable of hydrolyzing all major polysaccharides found in biomass. Examination of transcriptome data and secreted proteins suggests that the two fungi use shared approaches in the hydrolysis of cellulose and xylan but distinct mechanisms in pectin degradation. Characterization of the biomass-hydrolyzing activity of recombinant enzymes suggests that these organisms are highly efficient in biomass decomposition at both moderate and high temperatures. Furthermore, we present evidence suggesting that aside from representing a potential reservoir of thermostable enzymes, thermophilic fungi are amenable to manipulation using classical and molecular genetics.

  17. Comparative genomic analyses of Streptococcus mutans provide insights into chromosomal shuffling and species-specific content

    Directory of Open Access Journals (Sweden)

    Nakai Kenta

    2009-08-01

    Full Text Available Abstract Background Streptococcus mutans is the major pathogen of dental caries, and it occasionally causes infective endocarditis. While the pathogenicity of this species is distinct from other human pathogenic streptococci, the species-specific evolution of the genus Streptococcus and its genomic diversity are poorly understood. Results We have sequenced the complete genome of S. mutans serotype c strain NN2025, and compared it with the genome of UA159. The NN2025 genome is composed of 2,013,587 bp, and the two strains show highly conserved core-genome. However, comparison of the two S. mutans strains showed a large genomic inversion across the replication axis producing an X-shaped symmetrical DNA dot plot. This phenomenon was also observed between other streptococcal species, indicating that streptococcal genetic rearrangements across the replication axis play an important role in Streptococcus genetic shuffling. We further confirmed the genomic diversity among 95 clinical isolates using long-PCR analysis. Genomic diversity in S. mutans appears to occur frequently between insertion sequence (IS elements and transposons, and these diversity regions consist of restriction/modification systems, antimicrobial peptide synthesis systems, and transporters. S. mutans may preferentially reject the phage infection by clustered regularly interspaced short palindromic repeats (CRISPRs. In particular, the CRISPR-2 region, which is highly divergent between strains, in NN2025 has long repeated spacer sequences corresponding to the streptococcal phage genome. Conclusion These observations suggest that S. mutans strains evolve through chromosomal shuffling and that phage infection is not needed for gene acquisition. In contrast, S. pyogenes tolerates phage infection for acquisition of virulence determinants for niche adaptation.

  18. A critical assessment of cross-species detection of gene duplicates using comparative genomic hybridization

    Directory of Open Access Journals (Sweden)

    Renn Suzy CP

    2010-05-01

    Full Text Available Abstract Background Comparison of genomic DNA among closely related strains or species is a powerful approach for identifying variation in evolutionary processes. One potent source of genomic variation is gene duplication, which is prevalent among individuals and species. Array comparative genomic hybridization (aCGH has been successfully utilized to detect this variation among lineages. Here, beyond the demonstration that gene duplicates among species can be quantified with aCGH, we consider the effect of sequence divergence on the ability to detect gene duplicates. Results Using the X chromosome genomic content difference between male D. melanogaster and female D. yakuba and D. simulans, we describe a decrease in the ability to accurately measure genomic content (copy number for orthologs that are only 90% identical. We demonstrate that genome characteristics (e.g. chromatin environment and non-orthologous sequence similarity can also affect the ability to accurately measure genomic content. We describe a normalization strategy and statistical criteria to be used for the identification of gene duplicates among any species group for which an array platform is available from a closely related species. Conclusions Array CGH can be used to effectively identify gene duplication and genome content; however, certain biases are present due to sequence divergence and other genome characteristics resulting from the divergence between lineages. Highly conserved gene duplicates will be more readily recovered by aCGH. Duplicates that have been retained for a selective advantage due to directional selection acting on many loci in one or both gene copies are likely to be under-represented. The results of this study should inform the interpretation of both previously published and future work that employs this powerful technique.

  19. Exploring the zoonotic potential of Mycobacterium avium subspecies paratuberculosis through comparative genomics.

    Directory of Open Access Journals (Sweden)

    James W Wynne

    Full Text Available A comparative genomics approach was utilised to compare the genomes of Mycobacterium avium subspecies paratuberculosis (MAP isolated from early onset paediatric Crohn's disease (CD patients as well as Johne's diseased animals. Draft genome sequences were produced for MAP isolates derived from four CD patients, one ulcerative colitis (UC patient, and two non-inflammatory bowel disease (IBD control individuals using Illumina sequencing, complemented by comparative genome hybridisation (CGH. MAP isolates derived from two bovine and one ovine host were also subjected to whole genome sequencing and CGH. All seven human derived MAP isolates were highly genetically similar and clustered together with one bovine type isolate following phylogenetic analysis. Three other sequenced isolates (including the reference bovine derived isolate K10 were genetically distinct. The human isolates contained two large tandem duplications, the organisations of which were confirmed by PCR. Designated vGI-17 and vGI-18 these duplications spanned 63 and 109 open reading frames, respectively. PCR screening of over 30 additional MAP isolates (3 human derived, 27 animal derived and one environmental isolate confirmed that vGI-17 and vGI-18 are common across many isolates. Quantitative real-time PCR of vGI-17 demonstrated that the proportion of cells containing the vGI-17 duplication varied between 0.01 to 15% amongst isolates with human isolates containing a higher proportion of vGI-17 compared to most animal isolates. These findings suggest these duplications are transient genomic rearrangements. We hypothesise that the over-representation of vGI-17 in human derived MAP strains may enhance their ability to infect or persist within a human host by increasing genome redundancy and conferring crude regulation of protein expression across biologically important regions.

  20. Comparative chloroplast genomics: Analyses including new sequencesfrom the angiosperms Nuphar advena and Ranunculus macranthus

    Energy Technology Data Exchange (ETDEWEB)

    Raubeso, Linda A.; Peery, Rhiannon; Chumley, Timothy W.; Dziubek,Chris; Fourcade, H. Matthew; Boore, Jeffrey L.; Jansen, Robert K.

    2007-03-01

    The number of completely sequenced plastid genomes available is growing rapidly. This new array of sequences presents new opportunities to perform comparative analyses. In comparative studies, it is most useful to compare across wide phylogenetic spans and, within angiosperms, to include representatives from basally diverging lineages such as the new genomes reported here: Nuphar advena (from a basal-most lineage) and Ranunculus macranthus (from the basal group of eudicots). We report these two new plastid genome sequences and make comparisons (within angiosperms, seed plants, or all photosynthetic lineages) to evaluate features such as the status of ycf15 and ycf68 as protein coding genes, the distribution of simple sequence repeats (SSRs) and longer dispersed repeats (SDR), and patterns of nucleotide composition.

  1. Comparative genomic reconstruction of transcriptional networks controlling central metabolism in the Shewanella genus

    Directory of Open Access Journals (Sweden)

    Kovaleva Galina

    2011-06-01

    Full Text Available Abstract Background Genome-scale prediction of gene regulation and reconstruction of transcriptional regulatory networks in bacteria is one of the critical tasks of modern genomics. The Shewanella genus is comprised of metabolically versatile gamma-proteobacteria, whose lifestyles and natural environments are substantially different from Escherichia coli and other model bacterial species. The comparative genomics approaches and computational identification of regulatory sites are useful for the in silico reconstruction of transcriptional regulatory networks in bacteria. Results To explore conservation and variations in the Shewanella transcriptional networks we analyzed the repertoire of transcription factors and performed genomics-based reconstruction and comparative analysis of regulons in 16 Shewanella genomes. The inferred regulatory network includes 82 transcription factors and their DNA binding sites, 8 riboswitches and 6 translational attenuators. Forty five regulons were newly inferred from the genome context analysis, whereas others were propagated from previously characterized regulons in the Enterobacteria and Pseudomonas spp.. Multiple variations in regulatory strategies between the Shewanella spp. and E. coli include regulon contraction and expansion (as in the case of PdhR, HexR, FadR, numerous cases of recruiting non-orthologous regulators to control equivalent pathways (e.g. PsrA for fatty acid degradation and, conversely, orthologous regulators to control distinct pathways (e.g. TyrR, ArgR, Crp. Conclusions We tentatively defined the first reference collection of ~100 transcriptional regulons in 16 Shewanella genomes. The resulting regulatory network contains ~600 regulated genes per genome that are mostly involved in metabolism of carbohydrates, amino acids, fatty acids, vitamins, metals, and stress responses. Several reconstructed regulons including NagR for N-acetylglucosamine catabolism were experimentally validated in S

  2. The complex hybrid origins of the root knot nematodes revealed through comparative genomics

    Directory of Open Access Journals (Sweden)

    David H. Lunt

    2014-05-01

    Full Text Available Root knot nematodes (RKN can infect most of the world’s agricultural crop species and are among the most important of all plant pathogens. As yet however we have little understanding of their origins or the genomic basis of their extreme polyphagy. The most damaging pathogens reproduce by obligatory mitotic parthenogenesis and it has been suggested that these species originated from interspecific hybridizations between unknown parental taxa. We have sequenced the genome of the diploid meiotic parthenogen Meloidogyne floridensis, and use a comparative genomic approach to test the hypothesis that this species was involved in the hybrid origin of the tropical mitotic parthenogen Meloidogyne incognita. Phylogenomic analysis of gene families from M. floridensis, M. incognita and an outgroup species Meloidogyne hapla was carried out to trace the evolutionary history of these species’ genomes, and we demonstrate that M. floridensis was one of the parental species in the hybrid origins of M. incognita. Analysis of the M. floridensis genome itself revealed many gene loci present in divergent copies, as they are in M. incognita, indicating that it too had a hybrid origin. The triploid M. incognita is shown to be a complex double-hybrid between M. floridensis and a third, unidentified, parent. The agriculturally important RKN have very complex origins involving the mixing of several parental genomes by hybridization and their extreme polyphagy and success in agricultural environments may be related to this hybridization, producing transgressive variation on which natural selection can act. It is now clear that studying RKN variation via individual marker loci may fail due to the species’ convoluted origins, and multi-species population genomics is essential to understand the hybrid diversity and adaptive variation of this important species complex. This comparative genomic analysis provides a compelling example of the importance and complexity of

  3. Copy Number Variation Analysis by Array Analysis of Single Cells Following Whole Genome Amplification.

    Science.gov (United States)

    Dimitriadou, Eftychia; Zamani Esteki, Masoud; Vermeesch, Joris Robert

    2015-01-01

    Whole genome amplification is required to ensure the availability of sufficient material for copy number variation analysis of a genome deriving from an individual cell. Here, we describe the protocols we use for copy number variation analysis of non-fixed single cells by array-based approaches following single-cell isolation and whole genome amplification. We are focusing on two alternative protocols, an isothermal and a PCR-based whole genome amplification method, followed by either comparative genome hybridization (aCGH) or SNP array analysis, respectively.

  4. Genomics and Comparative Genomic Analyses Provide Insight into the Taxonomy and Pathogenic Potential of Novel Emmonsia Pathogens

    Science.gov (United States)

    Yang, Ying; Ye, Qiang; Li, Kang; Li, Zongwei; Bo, Xiaochen; Li, Zhen; Xu, Yingchun; Wang, Shengqi; Wang, Peng; Chen, Huipeng; Wang, Junzhi

    2017-01-01

    Over the last 50 years, newly described species of Emmonsia-like fungi have been implicated globally as sources of systemic human mycosis (emmonsiosis). Their ability to convert into yeast-like cells capable of replication and extra-pulmonary dissemination during the course of infection differentiates them from classical Emmonsia species. Immunocompromised patients are at highest risk of emmonsiosis and exhibit high mortality rates. In order to investigate the molecular basis for pathogenicity of the newly described Emmonsia species, genomic sequencing and comparative genomic analyses of Emmonsia sp. 5z489, which was isolated from a non-deliberately immunosuppressed diabetic patient in China and represents a novel seventh isolate of Emmonsia-like fungi, was performed. The genome size of 5z489 was 35.5 Mbp in length, which is ~5 Mbp larger than other Emmonsia strains. Further, 9,188 protein genes were predicted in the 5z489 genome and 16% of the assembly was identified as repetitive elements, which is the largest abundance in Emmonsia species. Phylogenetic analyses based on whole genome data classified 5z489 and CAC-2015a, another novel isolate, as members of the genus Emmonsia. Our analyses showed that divergences among Emmonsia occurred much earlier than other genera within the family Ajellomycetaceae, suggesting relatively distant evolutionary relationships among the genus. Through comparisons of Emmonsia species, we discovered significant pathogenicity characteristics within the genus as well as putative virulence factors that may play a role in the infection and pathogenicity of the novel Emmonsia strains. Moreover, our analyses revealed a novel distribution mode of DNA methylation patterns across the genome of 5z489, with >50% of methylated bases located in intergenic regions. These methylation patterns differ considerably from other reported fungi, where most methylation occurs in repetitive loci. It is unclear if this difference is related to physiological

  5. Comparative Genomic Study of the Thioredoxin Family in Photosynthetic Organisms with Emphasis on Populus trichocarpa

    Institute of Scientific and Technical Information of China (English)

    Kamel Chibani; Gunnar Wingsle; Jean-Pierre Jacquot; Eric Gelhaye; Nicolas Rouhier

    2009-01-01

    The recent genome sequencing of Populus trichocarpa and Vitis vinifera, two models of woody plants, of Sorghum bicolor, a model of monocot using C4 metabolism, and of the moss Physcomitrella patens, together with the availability of photosynthetic organism genomes allows performance of a comparative genomic study with organisms having different ways of life, reproduction modes, biological traits, and physiologies. Thioredoxins (Trxs) are small ubiq-uitous proteins involved in the reduction of disulfide bridges in a variety of target enzymes present in all sub-cellular compartments and involved in many biochemical reactions. The genes coding for these enzymes have been identified in these newly sequenced genomes and annotated. The gene content, organization and distribution were compared to other photosynthetic organisms, leading to a refined classification. This analysis revealed that higher plants and bryo-phytes have a more complex family compared to algae and cyanobacteria and to non-photosynthetic organisms, since poplar exhibits 49 genes coding for typical and atypical thioredoxins and thioredoxin reductases, namely one-third more than monocots such as Oryza sativa and S. bicolor. The higher number of Trxs in poplar is partially explained by gene duplication in the Trx m, h, and nucleoredoxin classes. Particular attention was paid to poplar genes with emphasis on Trx-like classes called Clot, thioredoxin-like, thioredoxins of the lilium type and nucleoredoxins, which were not described in depth in previous genomic studies.

  6. RegPredict: an integrated system for regulon inference in prokaryotes by comparative genomics approach

    Energy Technology Data Exchange (ETDEWEB)

    Novichkov, Pavel S.; Rodionov, Dmitry A.; Stavrovskaya, Elena D.; Novichkova, Elena S.; Kazakov, Alexey E.; Gelfand, Mikhail S.; Arkin, Adam P.; Mironov, Andrey A.; Dubchak, Inna

    2010-05-26

    RegPredict web server is designed to provide comparative genomics tools for reconstruction and analysis of microbial regulons using comparative genomics approach. The server allows the user to rapidly generate reference sets of regulons and regulatory motif profiles in a group of prokaryotic genomes. The new concept of a cluster of co-regulated orthologous operons allows the user to distribute the analysis of large regulons and to perform the comparative analysis of multiple clusters independently. Two major workflows currently implemented in RegPredict are: (i) regulon reconstruction for a known regulatory motif and (ii) ab initio inference of a novel regulon using several scenarios for the generation of starting gene sets. RegPredict provides a comprehensive collection of manually curated positional weight matrices of regulatory motifs. It is based on genomic sequences, ortholog and operon predictions from the MicrobesOnline. An interactive web interface of RegPredict integrates and presents diverse genomic and functional information about the candidate regulon members from several web resources. RegPredict is freely accessible at http://regpredict.lbl.gov.

  7. An initial comparative map of copy number variations in the goat (Capra hircus genome

    Directory of Open Access Journals (Sweden)

    Casadio Rita

    2010-11-01

    Full Text Available Abstract Background The goat (Capra hircus represents one of the most important farm animal species. It is reared in all continents with an estimated world population of about 800 million of animals. Despite its importance, studies on the goat genome are still in their infancy compared to those in other farm animal species. Comparative mapping between cattle and goat showed only a few rearrangements in agreement with the similarity of chromosome banding. We carried out a cross species cattle-goat array comparative genome hybridization (aCGH experiment in order to identify copy number variations (CNVs in the goat genome analysing animals of different breeds (Saanen, Camosciata delle Alpi, Girgentana, and Murciano-Granadina using a tiling oligonucleotide array with ~385,000 probes designed on the bovine genome. Results We identified a total of 161 CNVs (an average of 17.9 CNVs per goat, with the largest number in the Saanen breed and the lowest in the Camosciata delle Alpi goat. By aggregating overlapping CNVs identified in different animals we determined CNV regions (CNVRs: on the whole, we identified 127 CNVRs covering about 11.47 Mb of the virtual goat genome referred to the bovine genome (0.435% of the latter genome. These 127 CNVRs included 86 loss and 41 gain and ranged from about 24 kb to about 1.07 Mb with a mean and median equal to 90,292 bp and 49,530 bp, respectively. To evaluate whether the identified goat CNVRs overlap with those reported in the cattle genome, we compared our results with those obtained in four independent cattle experiments. Overlapping between goat and cattle CNVRs was highly significant (P Conclusions We describe a first map of goat CNVRs. This provides information on a comparative basis with the cattle genome by identifying putative recurrent interspecies CNVs between these two ruminant species. Several goat CNVs affect genes with important biological functions. Further studies are needed to evaluate the

  8. The genome sequence of E. coli W (ATCC 9637: comparative genome analysis and an improved genome-scale reconstruction of E. coli

    Directory of Open Access Journals (Sweden)

    Lee Sang

    2011-01-01

    Full Text Available Abstract Background Escherichia coli is a model prokaryote, an important pathogen, and a key organism for industrial biotechnology. E. coli W (ATCC 9637, one of four strains designated as safe for laboratory purposes, has not been sequenced. E. coli W is a fast-growing strain and is the only safe strain that can utilize sucrose as a carbon source. Lifecycle analysis has demonstrated that sucrose from sugarcane is a preferred carbon source for industrial bioprocesses. Results We have sequenced and annotated the genome of E. coli W. The chromosome is 4,900,968 bp and encodes 4,764 ORFs. Two plasmids, pRK1 (102,536 bp and pRK2 (5,360 bp, are also present. W has unique features relative to other sequenced laboratory strains (K-12, B and Crooks: it has a larger genome and belongs to phylogroup B1 rather than A. W also grows on a much broader range of carbon sources than does K-12. A genome-scale reconstruction was developed and validated in order to interrogate metabolic properties. Conclusions The genome of W is more similar to commensal and pathogenic B1 strains than phylogroup A strains, and therefore has greater utility for comparative analyses with these strains. W should therefore be the strain of choice, or 'type strain' for group B1 comparative analyses. The genome annotation and tools created here are expected to allow further utilization and development of E. coli W as an industrial organism for sucrose-based bioprocesses. Refinements in our E. coli metabolic reconstruction allow it to more accurately define E. coli metabolism relative to previous models.

  9. Titania nanotube array based photovoltaic cells

    Science.gov (United States)

    Yip, C. T.; Cheung, K. Y.; Djurišić, A. B.; Chan, W. K.

    2007-09-01

    It has been shown that dye sensitized solar cells (DSSCs) based on porous titanium dioxide (titania) layers have efficiencies exceeding 10%. Although porous structure has the advantage of large surface area for light harvesting, electron transport through the random nanoparticle network forming a porous film results in electron mobilities which are two orders of magnitude lower compared to the single crystal materials. Therefore, considerable efforts have been made to fabricate DSSC based on one dimensional nanostructures, such as nanowires or nanotubes. Titania nanotube arrays are typically made by anodization of titanium, followed by annealing to improve crystallinity. In this work, we investigated the influence of annealing temperature and annealing atmosphere on the crystal structure, the electron transport, and the solar cell performance of titania nanotube arrays. The titania nanotube arrays were prepared from electrochemically anodized titanium foils and their morphology and crystal structure were characterized by scanning electron microscopy and transmission electron microscopy. The crystal phases and the compositions of nanotube arrays were further investigated by X-ray diffraction for different annealing temperatures and X-ray photoelectron spectroscopy for different annealing atmospheres. For optimal annealing conditions, the short circuit current density of 4.27 mA/cm2 and power conversion efficiency of 1.30% could be achieved under AM 1.5 simulated solar irradiation for 2 μm long nanotubes.

  10. Comparing the Dictyostelium and Entamoeba genomes reveals an ancient split in the Conosa lineage.

    Directory of Open Access Journals (Sweden)

    Jie Song

    2005-12-01

    Full Text Available The Amoebozoa are a sister clade to the fungi and the animals, but are poorly sampled for completely sequenced genomes. The social amoeba Dictyostelium discoideum and amitochondriate pathogen Entamoeba histolytica are the first Amoebozoa with genomes completely sequenced. Both organisms are classified under the Conosa subphylum. To identify Amoebozoa-specific genomic elements, we compared these two genomes to each other and to other eukaryotic genomes. An expanded phylogenetic tree built from the complete predicted proteomes of 23 eukaryotes places the two amoebae in the same lineage, although the divergence is estimated to be greater than that between animals and fungi, and probably happened shortly after the Amoebozoa split from the opisthokont lineage. Most of the 1,500 orthologous gene families shared between the two amoebae are also shared with plant, animal, and fungal genomes. We found that only 42 gene families are distinct to the amoeba lineage; among these are a large number of proteins that contain repeats of the FNIP domain, and a putative transcription factor essential for proper cell type differentiation in D. discoideum. These Amoebozoa-specific genes may be useful in the design of novel diagnostics and therapies for amoebal pathologies.

  11. Evolution of a microbial nitrilase gene family: a comparative and environmental genomics study

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    Eads Jonathan R

    2005-08-01

    Full Text Available Abstract Background Completed genomes and environmental genomic sequences are bringing a significant contribution to understanding the evolution of gene families, microbial metabolism and community eco-physiology. Here, we used comparative genomics and phylogenetic analyses in conjunction with enzymatic data to probe the evolution and functions of a microbial nitrilase gene family. Nitrilases are relatively rare in bacterial genomes, their biological function being unclear. Results We examined the genetic neighborhood of the different subfamily genes and discovered conserved gene clusters or operons associated with specific nitrilase clades. The inferred evolutionary transitions that separate nitrilases which belong to different gene clusters correlated with changes in their enzymatic properties. We present evidence that Darwinian adaptation acted during one of those transitions and identified sites in the enzyme that may have been under positive selection. Conclusion Changes in the observed biochemical properties of the nitrilases associated with the different gene clusters are consistent with a hypothesis that those enzymes have been recruited to a novel metabolic pathway following gene duplication and neofunctionalization. These results demonstrate the benefits of combining environmental genomic sampling and completed genomes data with evolutionary and biochemical analyses in the study of gene families. They also open new directions for studying the functions of nitrilases and the genes they are associated with.

  12. IMG/M: integrated genome and metagenome comparative data analysis system.

    Science.gov (United States)

    Chen, I-Min A; Markowitz, Victor M; Chu, Ken; Palaniappan, Krishna; Szeto, Ernest; Pillay, Manoj; Ratner, Anna; Huang, Jinghua; Andersen, Evan; Huntemann, Marcel; Varghese, Neha; Hadjithomas, Michalis; Tennessen, Kristin; Nielsen, Torben; Ivanova, Natalia N; Kyrpides, Nikos C

    2017-01-04

    The Integrated Microbial Genomes with Microbiome Samples (IMG/M: https://img.jgi.doe.gov/m/) system contains annotated DNA and RNA sequence data of (i) archaeal, bacterial, eukaryotic and viral genomes from cultured organisms, (ii) single cell genomes (SCG) and genomes from metagenomes (GFM) from uncultured archaea, bacteria and viruses and (iii) metagenomes from environmental, host associated and engineered microbiome samples. Sequence data are generated by DOE's Joint Genome Institute (JGI), submitted by individual scientists, or collected from public sequence data archives. Structural and functional annotation is carried out by JGI's genome and metagenome annotation pipelines. A variety of analytical and visualization tools provide support for examining and comparing IMG/M's datasets. IMG/M allows open access interactive analysis of publicly available datasets, while manual curation, submission and access to private datasets and computationally intensive workspace-based analysis require login/password access to its expert review (ER) companion system (IMG/M ER: https://img.jgi.doe.gov/mer/). Since the last report published in the 2014 NAR Database Issue, IMG/M's dataset content has tripled in terms of number of datasets and overall protein coding genes, while its analysis tools have been extended to cope with the rapid growth in the number and size of datasets handled by the system.

  13. Mapping reads on a genomic sequence: an algorithmic overview and a practical comparative analysis.

    Science.gov (United States)

    Schbath, Sophie; Martin, Véronique; Zytnicki, Matthias; Fayolle, Julien; Loux, Valentin; Gibrat, Jean-François

    2012-06-01

    Mapping short reads against a reference genome is classically the first step of many next-generation sequencing data analyses, and it should be as accurate as possible. Because of the large number of reads to handle, numerous sophisticated algorithms have been developped in the last 3 years to tackle this problem. In this article, we first review the underlying algorithms used in most of the existing mapping tools, and then we compare the performance of nine of these tools on a well controled benchmark built for this purpose. We built a set of reads that exist in single or multiple copies in a reference genome and for which there is no mismatch, and a set of reads with three mismatches. We considered as reference genome both the human genome and a concatenation of all complete bacterial genomes. On each dataset, we quantified the capacity of the different tools to retrieve all the occurrences of the reads in the reference genome. Special attention was paid to reads uniquely reported and to reads with multiple hits.

  14. Comparative genomic analysis of multiple strains of two unusual plant pathogens: Pseudomonas corrugata and Pseudomonas mediterranea

    Directory of Open Access Journals (Sweden)

    Emmanouil A Trantas

    2015-08-01

    Full Text Available The non-fluorescent pseudomonads, Pseudomonas corrugata (Pcor and P. mediterranea (Pmed, are closely related species that cause pith necrosis, a disease of tomato that causes severe crop losses. However, they also show strong antagonistic effects against economically important pathogens, demonstrating their potential for utilization as biological control agents. In addition, their metabolic versatility makes them attractive for the production of commercial biomolecules and bioremediation. An extensive comparative genomics study is required to dissect the mechanisms that Pcor and Pmed employ to cause disease, prevent disease caused by other pathogens, and to mine their genomes for commercially significant chemical pathways. Here, we present the draft genomes of nine Pcor and Pmed strains from different geographical locations. This analysis covered significant genetic heterogeneity and allowed in-depth genomic comparison. All examined strains were able to trigger symptoms in tomato plants but not all induced a hypersensitive-like response in Nicotiana benthamiana. Genome-mining revealed the absence of a type III secretion system and of known type III effectors from all examined Pcor and Pmed strains. The lack of a type III secretion system appears to be unique among the plant pathogenic pseudomonads. Several gene clusters coding for type VI secretion system were detected in all genomes.

  15. Chromosomal imbalances in nasopharyngeal carcinoma: a meta-analysis of comparative genomic hybridization results

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    Jin Ping

    2006-01-01

    Full Text Available Abstract Nasopharyngeal carcinoma (NPC is a highly prevalent disease in Southeast Asia and its prevalence is clearly affected by genetic background. Various theories have been suggested for its high incidence in this geographical region but to these days no conclusive explanation has been identified. Chromosomal imbalances identifiable through comparative genomic hybridization may shed some light on common genetic alterations that may be of relevance to the onset and progression of NPC. Review of the literature, however, reveals contradictory results among reported findings possibly related to factors associated with patient selection, stage of disease, differences in methodological details etc. To increase the power of the analysis and attempt to identify commonalities among the reported findings, we performed a meta-analysis of results described in NPC tissues based on chromosomal comparative genomic hybridization (CGH. This meta-analysis revealed consistent patters in chromosomal abnormalities that appeared to cluster in specific "hot spots" along the genome following a stage-dependent progression.

  16. Comparative genome analysis of deleted genes in Shigella flexneri 2a strain 301

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Comparative genome analysis is performed between Shigella flexneri 2a strain 301 and its close relatives, the nonpathogenic E. Coli K-12 strain MG1655. Result shows that there are 136 DNA segments whose size is larger than 1000 bp absent from Shigella flexneri 2a strain 301, which is up to 717253 bp in total length. These deleted segments altogether contain 670 open reading frames (ORFs). Prediction of these ORFs indicates that there are 40% genes of unknown function. The other genes of definite functions encode metabolic enzymes, structure proteins, transcription regulatory factors and some elements correlated with horizontal transfer. Here we compare the complete genomic sequences of the two closely related species, which differ in pathogenic phenotype. To our knowledge, this not only reveals the difference of genomic sequence between the two important enteric pathogens for the first time, but also provides valuable clues to further researches in its process of physiological activity, pathogenesis and the evolution of enteric bacteria.

  17. Comparative genomics of Escherichia coli isolated from patients with inflammatory bowel disease

    DEFF Research Database (Denmark)

    Vejborg, Rebecca Munk; Hancock, Viktoria; Petersen, Andreas M.;

    2011-01-01

    Background: Inflammatory bowel disease (IBD) is used to describe a state of idiopathic, chronic inflammation of the gastrointestinal tract. The two main phenotypes of IBD are Crohn's disease (CD) and ulcerative colitis (UC). The major cause of IBD-associated mortality is colorectal cancer. Although...... both host-genetic and exogenous factors have been found to be involved, the aetiology of IBD is still not well understood. In this study we characterized thirteen Escherichia coli strains from patients with IBD by comparative genomic hybridization employing a microarray based on 31 sequenced E. coli...... genomes from a wide range of commensal and pathogenic isolates. Results: The IBD isolates, obtained from patients with UC and CD, displayed remarkably heterogeneous genomic profiles with little or no evidence of group-specific determinants. No IBD-specific genes were evident when compared...

  18. Gridded genomic libraries of different chordate species: a reference library system for basic and comparative genetic studies of chordate genomes.

    Science.gov (United States)

    Burgtorf, C; Welzel, K; Hasenbank, R; Zehetner, G; Weis, S; Lehrach, H

    1998-09-01

    The use of genomic libraries maintained in arrayed format is becoming a more and more popular tool for the analysis of molecular evolution and comparative molecular development. Being able to use already existing reference libraries considerably reduces the work load, and if results are made publicly available, it will facilitate in silica experiments in the future. Here we describe the construction and preliminary characterization of six cosmid libraries of different chordate species, Ciona intestinalis (Hemichordate), Branchiostoma floridae (Cephalochordate), Lampetra fluviatilis (Cyclostoma), Xiphophorus maculatus, and Danio rerio (Osteichthyes) in Lawrist7 and Fugu rubripes in Lawrist4.

  19. Comparative genome analysis: selection pressure on the Borrelia vls cassettes is essential for infectivity

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    Wilske Bettina

    2006-08-01

    Full Text Available Abstract Background At least three species of Borrelia burgdorferi sensu lato (Bbsl cause tick-borne Lyme disease. Previous work including the genome analysis of B. burgdorferi B31 and B. garinii PBi suggested a highly variable plasmid part. The frequent occurrence of duplicated sequence stretches, the observed plasmid redundancy, as well as the mainly unknown function and variability of plasmid encoded genes rendered the relationships between plasmids within and between species largely unresolvable. Results To gain further insight into Borreliae genome properties we completed the plasmid sequences of B. garinii PBi, added the genome of a further species, B. afzelii PKo, to our analysis, and compared for both species the genomes of pathogenic and apathogenic strains. The core of all Bbsl genomes consists of the chromosome and two plasmids collinear between all species. We also found additional groups of plasmids, which share large parts of their sequences. This makes it very likely that these plasmids are relatively stable and share common ancestors before the diversification of Borrelia species. The analysis of the differences between B. garinii PBi and B. afzelii PKo genomes of low and high passages revealed that the loss of infectivity is accompanied in both species by a loss of similar genetic material. Whereas B. garinii PBi suffered only from the break-off of a plasmid end, B. afzelii PKo lost more material, probably an entire plasmid. In both cases the vls gene locus encoding for variable surface proteins is affected. Conclusion The complete genome sequences of a B. garinii and a B. afzelii strain facilitate further comparative studies within the genus Borrellia. Our study shows that loss of infectivity can be traced back to only one single event in B. garinii PBi: the loss of the vls cassettes possibly due to error prone gene conversion. Similar albeit extended losses in B. afzelii PKo support the hypothesis that infectivity of Borrelia

  20. Comparative genomic reconstruction of transcriptional networks controlling central metabolism in the Shewanella genus

    Energy Technology Data Exchange (ETDEWEB)

    Rodionov, Dmitry A.; Novichkov, Pavel; Stavrovskaya, Elena D.; Rodionova, Irina A.; Li, Xiaoqing; Kazanov, Marat D.; Ravcheev, Dmitry A.; Gerasimova, Anna V.; Kazakov, Alexey E.; Kovaleva, Galina Y.; Permina, Elizabeth A.; Laikova, Olga N.; Overbeek, Ross; Romine, Margaret F.; Fredrickson, Jim K.; Arkin, Adam P.; Dubchak, Inna; Osterman, Andrei L.; Gelfand, Mikhail S.

    2011-06-15

    Genome-scale prediction of gene regulation and reconstruction of transcriptional regulatory networks in bacteria is one of the critical tasks of modern genomics. Despite the growing number of genome-scale gene expression studies, our abilities to convert the results of these studies into accurate regulatory annotations and to project them from model to other organisms are extremely limited. The comparative genomics approaches and computational identification of regulatory sites are useful for the in silico reconstruction of transcriptional regulatory networks in bacteria. The Shewanella genus is comprised of metabolically versatile gamma-proteobacteria, whose lifestyles and natural environments are substantially different from Escherichia coli and other model bacterial species. To explore conservation and variations in the Shewanella transcriptional networks we analyzed the repertoire of transcription factors and performed genomics-based reconstruction and comparative analysis of regulons in 16 Shewanella genomes. The inferred regulatory network includes 82 transcription factors and their DNA binding sites, 8 riboswitches and 6 translational attenuators. Forty five regulons were newly inferred from the genome context analysis, whereas others were propagated from previously characterized regulons in the Enterobacteria and Pseudomonas spp.. However, even orthologous regulators with conserved DNA-binding motifs may control substantially different gene sets, revealing striking differences in regulatory strategies between the Shewanella spp. and E. coli. Multiple examples of regulatory network rewiring include regulon contraction and expansion (as in the case of PdhR, HexR, FadR), and numerous cases of recruiting non-orthologous regulators to control equivalent pathways (e.g. NagR for N-acetylglucosamine catabolism and PsrA for fatty acid degradation) and, conversely, orthologous regulators to control distinct pathways (e.g. TyrR, ArgR, Crp).

  1. Comparative genome analysis of the high pathogenicity Salmonella Typhimurium strain UK-1.

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    Yingqin Luo

    Full Text Available Salmonella enterica serovar Typhimurium, a gram-negative facultative rod-shaped bacterium causing salmonellosis and foodborne disease, is one of the most common isolated Salmonella serovars in both developed and developing nations. Several S. Typhimurium genomes have been completed and many more genome-sequencing projects are underway. Comparative genome analysis of the multiple strains leads to a better understanding of the evolution of S. Typhimurium and its pathogenesis. S. Typhimurium strain UK-1 (belongs to phage type 1 is highly virulent when orally administered to mice and chickens and efficiently colonizes lymphoid tissues of these species. These characteristics make this strain a good choice for use in vaccine development. In fact, UK-1 has been used as the parent strain for a number of nonrecombinant and recombinant vaccine strains, including several commercial vaccines for poultry. In this study, we conducted a thorough comparative genome analysis of the UK-1 strain with other S. Typhimurium strains and examined the phenotypic impact of several genomic differences. Whole genomic comparison highlights an extremely close relationship between the UK-1 strain and other S. Typhimurium strains; however, many interesting genetic and genomic variations specific to UK-1 were explored. In particular, the deletion of a UK-1-specific gene that is highly similar to the gene encoding the T3SS effector protein NleC exhibited a significant decrease in oral virulence in BALB/c mice. The complete genetic complements in UK-1, especially those elements that contribute to virulence or aid in determining the diversity within bacterial species, provide key information in evaluating the functional characterization of important genetic determinants and for development of vaccines.

  2. Comparative Genomics of Erwinia amylovora and Related Erwinia Species—What do We Learn?

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    Youfu Zhao

    2011-09-01

    Full Text Available Erwinia amylovora, the causal agent of fire blight disease of apples and pears, is one of the most important plant bacterial pathogens with worldwide economic significance. Recent reports on the complete or draft genome sequences of four species in the genus Erwinia, including E. amylovora, E. pyrifoliae, E. tasmaniensis, and E. billingiae, have provided us near complete genetic information about this pathogen and its closely-related species. This review describes in silico subtractive hybridization-based comparative genomic analyses of eight genomes currently available, and highlights what we have learned from these comparative analyses, as well as genetic and functional genomic studies. Sequence analyses reinforce the assumption that E. amylovora is a relatively homogeneous species and support the current classification scheme of E. amylovora and its related species. The potential evolutionary origin of these Erwinia species is also proposed. The current understanding of the pathogen, its virulence mechanism and host specificity from genome sequencing data is summarized. Future research directions are also suggested.

  3. Comparative and functional genomic analyses of the pathogenicity of phytopathogen Xanthomonas campestris pv. campestris.

    Science.gov (United States)

    Qian, Wei; Jia, Yantao; Ren, Shuang-Xi; He, Yong-Qiang; Feng, Jia-Xun; Lu, Ling-Feng; Sun, Qihong; Ying, Ge; Tang, Dong-Jie; Tang, Hua; Wu, Wei; Hao, Pei; Wang, Lifeng; Jiang, Bo-Le; Zeng, Shenyan; Gu, Wen-Yi; Lu, Gang; Rong, Li; Tian, Yingchuan; Yao, Zhijian; Fu, Gang; Chen, Baoshan; Fang, Rongxiang; Qiang, Boqin; Chen, Zhu; Zhao, Guo-Ping; Tang, Ji-Liang; He, Chaozu

    2005-06-01

    Xanthomonas campestris pathovar campestris (Xcc) is the causative agent of crucifer black rot disease, which causes severe losses in agricultural yield world-wide. This bacterium is a model organism for studying plant-bacteria interactions. We sequenced the complete genome of Xcc 8004 (5,148,708 bp), which is highly conserved relative to that of Xcc ATCC 33913. Comparative genomics analysis indicated that, in addition to a significant genomic-scale rearrangement cross the replication axis between two IS1478 elements, loss and acquisition of blocks of genes, rather than point mutations, constitute the main genetic variation between the two Xcc strains. Screening of a high-density transposon insertional mutant library (16,512 clones) of Xcc 8004 against a host plant (Brassica oleraceae) identified 75 nonredundant, single-copy insertions in protein-coding sequences (CDSs) and intergenic regions. In addition to known virulence factors, full virulence was found to require several additional metabolic pathways and regulatory systems, such as fatty acid degradation, type IV secretion system, cell signaling, and amino acids and nucleotide metabolism. Among the identified pathogenicity-related genes, three of unknown function were found in Xcc 8004-specific chromosomal segments, revealing a direct correlation between genomic dynamics and Xcc virulence. The present combination of comparative and functional genomic analyses provides valuable information about the genetic basis of Xcc pathogenicity, which may offer novel insight toward the development of efficient methods for prevention of this important plant disease.

  4. arrayCGHbase: an analysis platform for comparative genomic hybridization microarrays

    Directory of Open Access Journals (Sweden)

    Moreau Yves

    2005-05-01

    Full Text Available Abstract Background The availability of the human genome sequence as well as the large number of physically accessible oligonucleotides, cDNA, and BAC clones across the entire genome has triggered and accelerated the use of several platforms for analysis of DNA copy number changes, amongst others microarray comparative genomic hybridization (arrayCGH. One of the challenges inherent to this new technology is the management and analysis of large numbers of data points generated in each individual experiment. Results We have developed arrayCGHbase, a comprehensive analysis platform for arrayCGH experiments consisting of a MIAME (Minimal Information About a Microarray Experiment supportive database using MySQL underlying a data mining web tool, to store, analyze, interpret, compare, and visualize arrayCGH results in a uniform and user-friendly format. Following its flexible design, arrayCGHbase is compatible with all existing and forthcoming arrayCGH platforms. Data can be exported in a multitude of formats, including BED files to map copy number information on the genome using the Ensembl or UCSC genome browser. Conclusion ArrayCGHbase is a web based and platform independent arrayCGH data analysis tool, that allows users to access the analysis suite through the internet or a local intranet after installation on a private server. ArrayCGHbase is available at http://medgen.ugent.be/arrayCGHbase/.

  5. Comparative genomic sequence analysis of strawberry and other rosids reveals significant microsynteny

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    Abbott Albert

    2010-06-01

    Full Text Available Abstract Background Fragaria belongs to the Rosaceae, an economically important family that includes a number of important fruit producing genera such as Malus and Prunus. Using genomic sequences from 50 Fragaria fosmids, we have examined the microsynteny between Fragaria and other plant models. Results In more than half of the strawberry fosmids, we found syntenic regions that are conserved in Populus, Vitis, Medicago and/or Arabidopsis with Populus containing the greatest number of syntenic regions with Fragaria. The longest syntenic region was between LG VIII of the poplar genome and the strawberry fosmid 72E18, where seven out of twelve predicted genes were collinear. We also observed an unexpectedly high level of conserved synteny between Fragaria (rosid I and Vitis (basal rosid. One of the strawberry fosmids, 34E24, contained a cluster of R gene analogs (RGAs with NBS and LRR domains. We detected clusters of RGAs with high sequence similarity to those in 34E24 in all the genomes compared. In the phylogenetic tree we have generated, all the NBS-LRR genes grouped together with Arabidopsis CNL-A type NBS-LRR genes. The Fragaria RGA grouped together with those of Vitis and Populus in the phylogenetic tree. Conclusions Our analysis shows considerable microsynteny between Fragaria and other plant genomes such as Populus, Medicago, Vitis, and Arabidopsis to a lesser degree. We also detected a cluster of NBS-LRR type genes that are conserved in all the genomes compared.

  6. MicrobesOnline: an integrated portal for comparative and functional genomics

    Energy Technology Data Exchange (ETDEWEB)

    Dehal, Paramvir; Joachimiak, Marcin; Price, Morgan; Bates, John; Baumohl, Jason; Chivian, Dylan; Friedland, Greg; Huang, Kathleen; Keller, Keith; Novichkov, Pavel; Dubchak, Inna; Alm, Eric; Arkin, Adam

    2011-07-14

    Since 2003, MicrobesOnline (http://www.microbesonline.org) has been providing a community resource for comparative and functional genome analysis. The portal includes over 1000 complete genomes of bacteria, archaea and fungi and thousands of expression microarrays from diverse organisms ranging from model organisms such as Escherichia coli and Saccharomyces cerevisiae to environmental microbes such as Desulfovibrio vulgaris and Shewanella oneidensis. To assist in annotating genes and in reconstructing their evolutionary history, MicrobesOnline includes a comparative genome browser based on phylogenetic trees for every gene family as well as a species tree. To identify co-regulated genes, MicrobesOnline can search for genes based on their expression profile, and provides tools for identifying regulatory motifs and seeing if they are conserved. MicrobesOnline also includes fast phylogenetic profile searches, comparative views of metabolic pathways, operon predictions, a workbench for sequence analysis and integration with RegTransBase and other microbial genome resources. The next update of MicrobesOnline will contain significant new functionality, including comparative analysis of metagenomic sequence data. Programmatic access to the database, along with source code and documentation, is available at http://microbesonline.org/programmers.html.

  7. MicrobesOnline: an integrated portal for comparative and functional genomics

    Energy Technology Data Exchange (ETDEWEB)

    Dehal, Paramvir S.; Joachimiak, Marcin P.; Price, Morgan N.; Bates, John T.; Baumohl, Jason K.; Chivian, Dylan; Friedland, Greg D.; Huang, Katherine H.; Keller, Keith; Novichkov, Pavel S.; Dubchak, Inna L.; Alm, Eric J.; Arkin, Adam P.

    2009-09-17

    Since 2003, MicrobesOnline (http://www.microbesonline.org) has been providing a community resource for comparative and functional genome analysis. The portal includes over 1000 complete genomes of bacteria, archaea and fungi and thousands of expression microarrays from diverse organisms ranging from model organisms such as Escherichia coli and Saccharomyces cerevisiae to environmental microbes such as Desulfovibrio vulgaris and Shewanella oneidensis. To assist in annotating genes and in reconstructing their evolutionary history, MicrobesOnline includes a comparative genome browser based on phylogenetic trees for every gene family as well as a species tree. To identify co-regulated genes, MicrobesOnline can search for genes based on their expression profile, and provides tools for identifying regulatory motifs and seeing if they are conserved. MicrobesOnline also includes fast phylogenetic profile searches, comparative views of metabolic pathways, operon predictions, a workbench for sequence analysis and integration with RegTransBase and other microbial genome resources. The next update of MicrobesOnline will contain significant new functionality, including comparative analysis of metagenomic sequence data. Programmatic access to the database, along with source code and documentation, is available at http://microbesonline.org/programmers.html.

  8. Comparative Genomic and Functional Analysis of Lactobacillus casei and Lactobacillus rhamnosus Strains Marketed as Probiotics

    NARCIS (Netherlands)

    Douillard, F.P.; Ribbera, A.; Järvinen, H.M.; Kant, R.; Pietilä, T.E.; Randazzo, C.L.; Paulin, L.; Laine, P.K.; Caggia, C.; Ossowski, von I.; Reunanen, J.; Satokari, R.; Salminen, S.; Palva, A.; Vos, de W.M.

    2013-01-01

    Four Lactobacillus strains were isolated from marketed probiotic products, including L. rhamnosus strains from Vifit (Friesland Campina) and Idoform (Ferrosan) and L. casei strains from Actimel (Danone) and Yakult (Yakult Honsa Co.). Their genomes and phenotypes were characterized and compared in de

  9. Metabolic capacity of Bacillus cereus strains ATCC 14579 and ATCC 10987 interlinked with comparative genomics.

    NARCIS (Netherlands)

    Mols, M.; Been, M.W.H.J. de; Zwietering, M.H.; Moezelaar, R.; Abee, T.

    2007-01-01

    Bacillus cereus is an important food-borne pathogen and spoilage organism. In this study, numerous phenotypes and the genomes of B.?cereus strains ATCC 14579 and ATCC 10987 were analysed to compare their metabolic capacity and stress resistance potential. The growth performance of the two strains wa

  10. Copy number variation in Fayoumi and Leghorn chickens analyzed using array comparative genomic hybridization

    NARCIS (Netherlands)

    Abernathy, J.; Li, X.; Jia, X.; Chou, W.; Lamont, S.J.; Crooijmans, R.P.M.A.; Zhou, H.

    2014-01-01

    Copy number variation refers to regions along chromosomes that harbor a type of structural variation, such as duplications or deletions. Copy number variants (CNVs) play a role in many important traits as well as in genetic diversity. Previous analyses of chickens using array comparative genomic hyb

  11. Features of 5'-splice-site efficiency derived from disease-causing mutations and comparative genomics

    DEFF Research Database (Denmark)

    Roca, Xavier; Olson, Andrew J; Rao, Atmakuri R

    2007-01-01

    Many human diseases, including Fanconi anemia, hemophilia B, neurofibromatosis, and phenylketonuria, can be caused by 5'-splice-site (5'ss) mutations that are not predicted to disrupt splicing, according to position weight matrices. By using comparative genomics, we identify pairwise dependencies...

  12. DNA copy number aberrations in breast cancer by array comparative genomic hybridization

    DEFF Research Database (Denmark)

    Li, J.; Wang, K.; Li, S.;

    2009-01-01

    Array comparative genomic hybridization (CGH) has been popularly used for analyzing DNA copy number variations in diseases like cancer. In this study, we investigated 82 sporadic samples from 49 breast cancer patients using 1-Mb resolution bacterial artificial chromosome CGH arrays. A number of h...

  13. Comparative genomic and in situ hybridization of germ cell tumors of the infantile testis

    NARCIS (Netherlands)

    Mostert, M; Rosenberg, C; Stoop, H; Schuyer, M; Timmer, A; Oosterhuis, W; Looijenga, L

    2000-01-01

    Chromosomal information on germ cell tumors of the infantile testis, ie, teratomas and yolk sac tumors, is limited and controversial. We studied two teratomas and four yolk sac tumors using comparative genomic hybridization (CGH) and in situ hybridization. No chromosomal anomalies were found in the

  14. Comparative functional genomics of amino acid metabolism of lactic acid bacteria

    NARCIS (Netherlands)

    Pastink, M.I.

    2009-01-01

    The amino acid metabolism of lactic acid bacteria used as starters in industrial fermentations has profound effects on the quality of the fermented foods. The work described in this PhD thesis was initiated to use genomics technologies and a comparative approach to link the gene content of some well

  15. Comparative genomic hybridization detects novel amplifications in fibroadenomas of the breast

    DEFF Research Database (Denmark)

    Ojopi, E P; Rogatto, S R; Caldeira, J R

    2001-01-01

    Comparative genomic hybridization analysis was performed for identification of chromosomal imbalances in 23 samples of fibroadenomas of the breast. Chromosomal gains rather than losses were a feature of these lesions. Only two cases with a familial and/or previous history of breast lesions had gain...

  16. Comparative genome-scale metabolic modeling of actinomycetes : The topology of essential core metabolism

    NARCIS (Netherlands)

    Alam, Mohammad Tauqeer; Medema, Marnix H.; Takano, Eriko; Breitling, Rainer; Gojobori, Takashi

    2011-01-01

    Actinomycetes are highly important bacteria. On one hand, some of them cause severe human and plant diseases, on the other hand, many species are known for their ability to produce antibiotics. Here we report the results of a comparative analysis of genome-scale metabolic models of 37 species of act

  17. Comparative genome-scale metabolic modeling of actinomycetes: the topology of essential core metabolism.

    NARCIS (Netherlands)

    Alam, M.T.; Medema, M.H.; Takano, E.; Breitling, R.

    2011-01-01

    Actinomycetes are highly important bacteria. On one hand, some of them cause severe human and plant diseases, on the other hand, many species are known for their ability to produce antibiotics. Here we report the results of a comparative analysis of genome-scale metabolic models of 37 species of act

  18. Comparative genomic hybridization: technical development and cytogenetic aspects for routine use in clinical laboratories.

    Science.gov (United States)

    Lapierre, J M; Cacheux, V; Da Silva, F; Collot, N; Hervy, N; Wiss, J; Tachdjian, G

    1998-01-01

    Comparative genomic hybridization (CGH) offers a new global approach for detection of chromosomal material imbalances of the entire genome in a single experiment without cell culture. In this paper, we discuss the technical development and the cytogenetic aspects of CGH in a clinical laboratory. Based only on the visual inspection of CGH metaphase spreads, the correct identification of numerical and structural anomalies are reported. No commercial image analysis software was required in these experiments. We have demonstrated that this new technology can be set up easily for routine use in a clinical cytogenetics laboratory.

  19. Bootstrap, Bayesian probability and maximum likelihood mapping: exploring new tools for comparative genome analyses

    Directory of Open Access Journals (Sweden)

    Gogarten J Peter

    2002-02-01

    Full Text Available Abstract Background Horizontal gene transfer (HGT played an important role in shaping microbial genomes. In addition to genes under sporadic selection, HGT also affects housekeeping genes and those involved in information processing, even ribosomal RNA encoding genes. Here we describe tools that provide an assessment and graphic illustration of the mosaic nature of microbial genomes. Results We adapted the Maximum Likelihood (ML mapping to the analyses of all detected quartets of orthologous genes found in four genomes. We have automated the assembly and analyses of these quartets of orthologs given the selection of four genomes. We compared the ML-mapping approach to more rigorous Bayesian probability and Bootstrap mapping techniques. The latter two approaches appear to be more conservative than the ML-mapping approach, but qualitatively all three approaches give equivalent results. All three tools were tested on mitochondrial genomes, which presumably were inherited as a single linkage group. Conclusions In some instances of interphylum relationships we find nearly equal numbers of quartets strongly supporting the three possible topologies. In contrast, our analyses of genome quartets containing the cyanobacterium Synechocystis sp. indicate that a large part of the cyanobacterial genome is related to that of low GC Gram positives. Other groups that had been suggested as sister groups to the cyanobacteria contain many fewer genes that group with the Synechocystis orthologs. Interdomain comparisons of genome quartets containing the archaeon Halobacterium sp. revealed that Halobacterium sp. shares more genes with Bacteria that live in the same environment than with Bacteria that are more closely related based on rRNA phylogeny . Many of these genes encode proteins involved in substrate transport and metabolism and in information storage and processing. The performed analyses demonstrate that relationships among prokaryotes cannot be accurately

  20. An HMM-based comparative genomic framework for detecting introgression in eukaryotes.

    Directory of Open Access Journals (Sweden)

    Kevin J Liu

    2014-06-01

    Full Text Available One outcome of interspecific hybridization and subsequent effects of evolutionary forces is introgression, which is the integration of genetic material from one species into the genome of an individual in another species. The evolution of several groups of eukaryotic species has involved hybridization, and cases of adaptation through introgression have been already established. In this work, we report on PhyloNet-HMM-a new comparative genomic framework for detecting introgression in genomes. PhyloNet-HMM combines phylogenetic networks with hidden Markov models (HMMs to simultaneously capture the (potentially reticulate evolutionary history of the genomes and dependencies within genomes. A novel aspect of our work is that it also accounts for incomplete lineage sorting and dependence across loci. Application of our model to variation data from chromosome 7 in the mouse (Mus musculus domesticus genome detected a recently reported adaptive introgression event involving the rodent poison resistance gene Vkorc1, in addition to other newly detected introgressed genomic regions. Based on our analysis, it is estimated that about 9% of all sites within chromosome 7 are of introgressive origin (these cover about 13 Mbp of chromosome 7, and over 300 genes. Further, our model detected no introgression in a negative control data set. We also found that our model accurately detected introgression and other evolutionary processes from synthetic data sets simulated under the coalescent model with recombination, isolation, and migration. Our work provides a powerful framework for systematic analysis of introgression while simultaneously accounting for dependence across sites, point mutations, recombination, and ancestral polymorphism.

  1. Genome Sequencing and Comparative Analysis of the Biocontrol Agent Trichoderma harzianum sensu stricto TR274

    Energy Technology Data Exchange (ETDEWEB)

    Steindorff, Andrei S.; Noronha, Elilane F.; Ulhoa, Cirano J.; Kuo, Alan; Salamov, Asaf A.; Haridas, Sajeet; Riley, Robert W.; Druzhinina, Irina S.; Kubicek, Christian P.; Grigoriev, Igor V.

    2015-03-17

    Biological control is a complex process which requires many mechanisms and a high diversity of biochemical pathways. The species of Trichoderma harzianum are well known for their biocontrol activity against many plant pathogens. To gain new insights into the biocontrol mechanism used by T. harzianum, we sequenced the isolate TR274 genome using Illumina. The assembly was performed using AllPaths-LG with a maximum coverage of 100x. The assembly resulted in 2282 contigs with a N50 of 37033bp. The genome size generated was 40.8 Mb and the GC content was 47.7%, similar to other Trichoderma genomes. Using the JGI Annotation Pipeline we predicted 13,932 genes with a high transcriptome support. CEGMA tests suggested 100% genome completeness and 97.9% of RNA-SEQ reads were mapped to the genome. The phylogenetic comparison using orthologous proteins with all Trichoderma genomes sequenced at JGI, corroborates the Trichoderma (T. asperellum and T. atroviride), Longibrachiatum (T. reesei and T. longibrachiatum) and Pachibasium (T. harzianum and T. virens) section division described previously. The comparison between two Trichoderma harzianum species suggests a high genome similarity but some strain-specific expansions. Analyses of the secondary metabolites, CAZymes, transporters, proteases, transcription factors were performed. The Pachybasium section expanded virtually all categories analyzed compared with the other sections, specially Longibrachiatum section, that shows a clear contraction. These results suggests that these proteins families have an important role in their respective phenotypes. Future analysis will improve the understanding of this complex genus and give some insights about its lifestyle and the interactions with the environment.

  2. The SOL Genomics Network. A Comparative Resource for Solanaceae Biology and Beyond1

    Science.gov (United States)

    Mueller, Lukas A.; Solow, Teri H.; Taylor, Nicolas; Skwarecki, Beth; Buels, Robert; Binns, John; Lin, Chenwei; Wright, Mark H.; Ahrens, Robert; Wang, Ying; Herbst, Evan V.; Keyder, Emil R.; Menda, Naama; Zamir, Dani; Tanksley, Steven D.

    2005-01-01

    The SOL Genomics Network (SGN; http://sgn.cornell.edu) is a rapidly evolving comparative resource for the plants of the Solanaceae family, which includes important crop and model plants such as potato (Solanum tuberosum), eggplant (Solanum melongena), pepper (Capsicum annuum), and tomato (Solanum lycopersicum). The aim of SGN is to relate these species to one another using a comparative genomics approach and to tie them to the other dicots through the fully sequenced genome of Arabidopsis (Arabidopsis thaliana). SGN currently houses map and marker data for Solanaceae species, a large expressed sequence tag collection with computationally derived unigene sets, an extensive database of phenotypic information for a mutagenized tomato population, and associated tools such as real-time quantitative trait loci. Recently, the International Solanaceae Project (SOL) was formed as an umbrella organization for Solanaceae research in over 30 countries to address important questions in plant biology. The first cornerstone of the SOL project is the sequencing of the entire euchromatic portion of the tomato genome. SGN is collaborating with other bioinformatics centers in building the bioinformatics infrastructure for the tomato sequencing project and implementing the bioinformatics strategy of the larger SOL project. The overarching goal of SGN is to make information available in an intuitive comparative format, thereby facilitating a systems approach to investigations into the basis of adaptation and phenotypic diversity in the Solanaceae family, other species in the Asterid clade such as coffee (Coffea arabica), Rubiaciae, and beyond. PMID:16010005

  3. Comparative analysis of genome maintenance genes in naked mole rat, mouse, and human

    Science.gov (United States)

    MacRae, Sheila L; Zhang, Quanwei; Lemetre, Christophe; Seim, Inge; Calder, Robert B; Hoeijmakers, Jan; Suh, Yousin; Gladyshev, Vadim N; Seluanov, Andrei; Gorbunova, Vera; Vijg, Jan; Zhang, Zhengdong D

    2015-01-01

    Genome maintenance (GM) is an essential defense system against aging and cancer, as both are characterized by increased genome instability. Here, we compared the copy number variation and mutation rate of 518 GM-associated genes in the naked mole rat (NMR), mouse, and human genomes. GM genes appeared to be strongly conserved, with copy number variation in only four genes. Interestingly, we found NMR to have a higher copy number of CEBPG, a regulator of DNA repair, and TINF2, a protector of telomere integrity. NMR, as well as human, was also found to have a lower rate of germline nucleotide substitution than the mouse. Together, the data suggest that the long-lived NMR, as well as human, has more robust GM than mouse and identifies new targets for the analysis of the exceptional longevity of the NMR. PMID:25645816

  4. Comparative genomic analysis of Brazilian Leptospira kirschneri serogroup Pomona serovar Mozdok

    Directory of Open Access Journals (Sweden)

    Luisa Z Moreno

    2016-08-01

    Full Text Available Leptospira kirschneri is one of the pathogenic species of the Leptospira genus. Human and animal infection from L. kirschneri gained further attention over the last few decades. Here we present the isolation and characterisation of Brazilian L. kirschneri serogroup Pomona serovar Mozdok strain M36/05 and the comparative genomic analysis with Brazilian human strain 61H. The M36/05 strain caused pulmonary hemorrhagic lesions in the hamster model, showing high virulence. The studied genomes presented high symmetrical identity and the in silico multilocus sequence typing analysis resulted in a new allelic profile (ST101 that so far has only been associated with the Brazilian L. kirschneri serogroup Pomona serovar Mozdok strains. Considering the environmental conditions and high genomic similarity observed between strains, we suggest the existence of a Brazilian L. kirschneri serogroup Pomona serovar Mozdok lineage that could represent a high public health risk; further studies are necessary to confirm the lineage significance and distribution.

  5. Comparative genomics study for identification of putative drug targets in Salmonella typhi Ty2.

    Science.gov (United States)

    Batool, Nisha; Waqar, Maleeha; Batool, Sidra

    2016-01-15

    Typhoid presents a major health concern in developing countries with an estimated annual infection rate of 21 million. The disease is caused by Salmonella typhi, a pathogenic bacterium acquiring multiple drug resistance. We aim to identify proteins that could prove to be putative drug targets in the genome of S. typhi str. Ty2. We employed comparative and subtractive genomics to identify targets that are absent in humans and are essential to S. typhi Ty2. We concluded that 46 proteins essential to pathogen are absent in the host genome. Filtration on the basis of drug target prioritization singled out 20 potentially therapeutic targets. Their absence in the host and specificity to S. typhi Ty2 makes them ideal targets for treating typhoid in Homo sapiens. 3D structures of two of the final target enzymes, MurA and MurB have been predicted via homology modeling which are then used for a docking study.

  6. Comparative cytogenetic analysis of Avena macrostachya and diploid C-genome Avena species.

    Science.gov (United States)

    Badaeva, Ekaterina D; Shelukhina, Olga Yu; Diederichsen, Axel; Loskutov, Igor G; Pukhalskiy, Vitaly A

    2010-02-01

    The chromosome set of Avena macrostachya Balansa ex Coss. et Durieu was analyzed using C-banding and fluorescence in situ hybridization with 5S and 18S-5.8S-26S rRNA gene probes, and the results were compared with the C-genome diploid Avena L. species. The location of major nucleolar organizer regions and 5S rDNA sites on different chromosomes confirmed the affiliation of A. macrostachya with the C-genome group. However, the symmetric karyotype, the absence of "diffuse heterochromatin" and the location of large C-band complexes in proximal chromosome regions pointed to an isolated position of A. macrostachya from other Avena species. Based on the distribution of rDNA loci on the C-genome chromosomes of diploid and polyploid Avena species, we propose a model of the chromosome alterations that occurred during the evolution of oat species.

  7. Comparative genomic analysis of Brazilian Leptospira kirschneri serogroup Pomona serovar Mozdok

    Science.gov (United States)

    Moreno, Luisa Z; Kremer, Frederico S; Miraglia, Fabiana; Loureiro, Ana P; Eslabao, Marcus R; Dellagostin, Odir A; Lilenbaum, Walter; Moreno, Andrea M

    2016-01-01

    Leptospira kirschneri is one of the pathogenic species of the Leptospira genus. Human and animal infection from L. kirschneri gained further attention over the last few decades. Here we present the isolation and characterisation of Brazilian L. kirschneri serogroup Pomona serovar Mozdok strain M36/05 and the comparative genomic analysis with Brazilian human strain 61H. The M36/05 strain caused pulmonary hemorrhagic lesions in the hamster model, showing high virulence. The studied genomes presented high symmetrical identity and the in silico multilocus sequence typing analysis resulted in a new allelic profile (ST101) that so far has only been associated with the Brazilian L. kirschneri serogroup Pomona serovar Mozdok strains. Considering the environmental conditions and high genomic similarity observed between strains, we suggest the existence of a Brazilian L. kirschneri serogroup Pomona serovar Mozdok lineage that could represent a high public health risk; further studies are necessary to confirm the lineage significance and distribution. PMID:27581124

  8. SINGLE CELL DEGENERATE OLIGONUCLEOTIDE PRIMER-PCR AND COMPARATIVE GENOMIC HYBRIDIZATION WITH MODIFIED CONTROL REFERENCE

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    For investigating the possibility of applying degenerate oligonucleotide primer PCR (DOP-PCR) and comparative genomic hybridization (CGH) technique to analyses of genomic genetics in a single cell, the whole genomic DNA of a single cell with XX, XY, XO, XXY, +13 or +21 was amplified by DOP-PCR. Single cell DOP-PCR CGHs with conventional and modified control references, the genomic DNA and a single cell DOP-PCR product from normal male, were carried out respectively. The results showed that the average profile of the fluorescence intensity ratio in CGH with the genomic DNA as reference fluctuates much and that the standard deviation in about 30% haploid is beyond the normal limits. False positive hyper-representation was found to exist in X chromosome while trisomy 13 and 21 were not detected. However, the distributions of the mean and the standard deviation of the ratio in the CGH with DOP-PCR product as reference were quite acceptable. The copy number changes of chromosome X,Y,13 and 21 were revealed. Those results suggested that there is unrandom unequal amplification in a single cell DOP-PCR. Using a single DOP-PCR product as reference can decrease its influence on CGH. Single cell DOP-PCR-CGH and its application in the genetic analyses of preimplantation embryo or fetal cell in maternal blood may be possible.

  9. Comparing Memory-Efficient Genome Assemblers on Stand-Alone and Cloud Infrastructures

    KAUST Repository

    Kleftogiannis, Dimitrios A.

    2013-09-27

    A fundamental problem in bioinformatics is genome assembly. Next-generation sequencing (NGS) technologies produce large volumes of fragmented genome reads, which require large amounts of memory to assemble the complete genome efficiently. With recent improvements in DNA sequencing technologies, it is expected that the memory footprint required for the assembly process will increase dramatically and will emerge as a limiting factor in processing widely available NGS-generated reads. In this report, we compare current memory-efficient techniques for genome assembly with respect to quality, memory consumption and execution time. Our experiments prove that it is possible to generate draft assemblies of reasonable quality on conventional multi-purpose computers with very limited available memory by choosing suitable assembly methods. Our study reveals the minimum memory requirements for different assembly programs even when data volume exceeds memory capacity by orders of magnitude. By combining existing methodologies, we propose two general assembly strategies that can improve short-read assembly approaches and result in reduction of the memory footprint. Finally, we discuss the possibility of utilizing cloud infrastructures for genome assembly and we comment on some findings regarding suitable computational resources for assembly.

  10. Complete chloroplast genome sequence of Omani lime (Citrus aurantiifolia and comparative analysis within the rosids.

    Directory of Open Access Journals (Sweden)

    Huei-Jiun Su

    Full Text Available The genus Citrus contains many economically important fruits that are grown worldwide for their high nutritional and medicinal value. Due to frequent hybridizations among species and cultivars, the exact number of natural species and the taxonomic relationships within this genus are unclear. To compare the differences between the Citrus chloroplast genomes and to develop useful genetic markers, we used a reference-assisted approach to assemble the complete chloroplast genome of Omani lime (C. aurantiifolia. The complete C. aurantiifolia chloroplast genome is 159,893 bp in length; the organization and gene content are similar to most of the rosids lineages characterized to date. Through comparison with the sweet orange (C. sinensis chloroplast genome, we identified three intergenic regions and 94 simple sequence repeats (SSRs that are potentially informative markers with resolution for interspecific relationships. These markers can be utilized to better understand the origin of cultivated Citrus. A comparison among 72 species belonging to 10 families of representative rosids lineages also provides new insights into their chloroplast genome evolution.

  11. Complete chloroplast genome sequence of Omani lime (Citrus aurantiifolia) and comparative analysis within the rosids.

    Science.gov (United States)

    Su, Huei-Jiun; Hogenhout, Saskia A; Al-Sadi, Abdullah M; Kuo, Chih-Horng

    2014-01-01

    The genus Citrus contains many economically important fruits that are grown worldwide for their high nutritional and medicinal value. Due to frequent hybridizations among species and cultivars, the exact number of natural species and the taxonomic relationships within this genus are unclear. To compare the differences between the Citrus chloroplast genomes and to develop useful genetic markers, we used a reference-assisted approach to assemble the complete chloroplast genome of Omani lime (C. aurantiifolia). The complete C. aurantiifolia chloroplast genome is 159,893 bp in length; the organization and gene content are similar to most of the rosids lineages characterized to date. Through comparison with the sweet orange (C. sinensis) chloroplast genome, we identified three intergenic regions and 94 simple sequence repeats (SSRs) that are potentially informative markers with resolution for interspecific relationships. These markers can be utilized to better understand the origin of cultivated Citrus. A comparison among 72 species belonging to 10 families of representative rosids lineages also provides new insights into their chloroplast genome evolution.

  12. Comparative genomics of the fungal pathogens Candida dubliniensis and Candida albicans.

    LENUS (Irish Health Repository)

    Jackson, Andrew P

    2009-12-01

    Candida dubliniensis is the closest known relative of Candida albicans, the most pathogenic yeast species in humans. However, despite both species sharing many phenotypic characteristics, including the ability to form true hyphae, C. dubliniensis is a significantly less virulent and less versatile pathogen. Therefore, to identify C. albicans-specific genes that may be responsible for an increased capacity to cause disease, we have sequenced the C. dubliniensis genome and compared it with the known C. albicans genome sequence. Although the two genome sequences are highly similar and synteny is conserved throughout, 168 species-specific genes are identified, including some encoding known hyphal-specific virulence factors, such as the aspartyl proteinases Sap4 and Sap5 and the proposed invasin Als3. Among the 115 pseudogenes confirmed in C. dubliniensis are orthologs of several filamentous growth regulator (FGR) genes that also have suspected roles in pathogenesis. However, the principal differences in genomic repertoire concern expansion of the TLO gene family of putative transcription factors and the IFA family of putative transmembrane proteins in C. albicans, which represent novel candidate virulence-associated factors. The results suggest that the recent evolutionary histories of C. albicans and C. dubliniensis are quite different. While gene families instrumental in pathogenesis have been elaborated in C. albicans, C. dubliniensis has lost genomic capacity and key pathogenic functions. This could explain why C. albicans is a more potent pathogen in humans than C. dubliniensis.

  13. Comparative genomics of Gossypium and Arabidopsis: Unraveling the consequences of both ancient and recent polyploidy

    Science.gov (United States)

    Rong, Junkang; Bowers, John E.; Schulze, Stefan R.; Waghmare, Vijay N.; Rogers, Carl J.; Pierce, Gary J.; Zhang, Hua; Estill, James C.; Paterson, Andrew H.

    2005-01-01

    Both ancient and recent polyploidy, together with post-polyploidization loss of many duplicated gene copies, complicates angiosperm comparative genomics. To explore an approach by which these challenges might be mitigated, genetic maps of extant diploid and tetraploid cottons (Gossypium spp.) were used to infer the approximate order of 3016 loci along the chromosomes of their hypothetical common ancestor. The inferred Gossypium gene order corresponded more closely than the original maps did to a similarly inferred ancestral gene order predating an independent paleopolyploidization (α) in Arabidopsis. At least 59% of the cotton map and 53% of the Arabidopsis transcriptome showed correspondence in multilocus gene arrangements based on one or both of two software packages (CrimeStatII, FISH). Genomic regions in which chromosome structural rearrangement has been rapid (obscuring gene order correspondence) have also been subject to greater divergence of individual gene sequences. About 26%-44% of corresponding regions involved multiple Arabidopsis or cotton chromosomes, in some cases consistent with known, more ancient, duplications. The genomic distributions of multiple-locus probes provided early insight into the consequences for chromosome structure of an ancient large-scale duplication in cotton. Inferences that mitigate the consequences of ancient duplications improve leveraging of genomic information for model organisms in the study of more complex genomes. PMID:16109973

  14. Comparative Genomics of Interreplichore Translocations in Bacteria: A Measure of Chromosome Topology?

    Science.gov (United States)

    Khedkar, Supriya; Seshasayee, Aswin Sai Narain

    2016-06-01

    Genomes evolve not only in base sequence but also in terms of their architecture, defined by gene organization and chromosome topology. Whereas genome sequence data inform us about the changes in base sequences for a large variety of organisms, the study of chromosome topology is restricted to a few model organisms studied using microscopy and chromosome conformation capture techniques. Here, we exploit whole genome sequence data to study the link between gene organization and chromosome topology in bacteria. Using comparative genomics across ∼250 pairs of closely related bacteria we show that: (a) many organisms show a high degree of interreplichore translocations throughout the chromosome and not limited to the inversion-prone terminus (ter) or the origin of replication (oriC); (b) translocation maps may reflect chromosome topologies; and (c) symmetric interreplichore translocations do not disrupt the distance of a gene from oriC or affect gene expression states or strand biases in gene densities. In summary, we suggest that translocation maps might be a first line in defining a gross chromosome topology given a pair of closely related genome sequences.

  15. ReplicationDomain: a visualization tool and comparative database for genome-wide replication timing data

    Directory of Open Access Journals (Sweden)

    Yokochi Tomoki

    2008-12-01

    Full Text Available Abstract Background Eukaryotic DNA replication is regulated at the level of large chromosomal domains (0.5–5 megabases in mammals within which replicons are activated relatively synchronously. These domains replicate in a specific temporal order during S-phase and our genome-wide analyses of replication timing have demonstrated that this temporal order of domain replication is a stable property of specific cell types. Results We have developed ReplicationDomain http://www.replicationdomain.org as a web-based database for analysis of genome-wide replication timing maps (replication profiles from various cell lines and species. This database also provides comparative information of transcriptional expression and is configured to display any genome-wide property (for instance, ChIP-Chip or ChIP-Seq data via an interactive web interface. Our published microarray data sets are publicly available. Users may graphically display these data sets for a selected genomic region and download the data displayed as text files, or alternatively, download complete genome-wide data sets. Furthermore, we have implemented a user registration system that allows registered users to upload their own data sets. Upon uploading, registered users may choose to: (1 view their data sets privately without sharing; (2 share with other registered users; or (3 make their published or "in press" data sets publicly available, which can fulfill journal and funding agencies' requirements for data sharing. Conclusion ReplicationDomain is a novel and powerful tool to facilitate the comparative visualization of replication timing in various cell types as well as other genome-wide chromatin features and is considerably faster and more convenient than existing browsers when viewing multi-megabase segments of chromosomes. Furthermore, the data upload function with the option of private viewing or sharing of data sets between registered users should be a valuable resource for the

  16. Evolution and comparative genomics of Campylobacter jejuni ST-677 clonal complex.

    Science.gov (United States)

    Kivistö, Rauni I; Kovanen, Sara; Skarp-de Haan, Astrid; Schott, Thomas; Rahkio, Marjatta; Rossi, Mirko; Hänninen, Marja-Liisa

    2014-09-04

    Campylobacter is the most common bacterial cause of gastroenteritis in the European Union with over 200,000 laboratory-confirmed cases reported annually. This is the first study to describe findings related to comparative genomics analyses of the sequence type (ST)-677 clonal complex (CC), a Campylobacter jejuni lineage associated with bacteremia cases in humans. We performed whole-genome sequencing, using Illumina HiSeq sequencing technology, on five related ST-677 CC isolates from two chicken farms to identify microevolution taking place at the farms. Our further aim was to identify novel putative virulence determinants from the ST-677 CC genomes. For this purpose, clinical isolates of the same CC were included in comparative genomic analyses against well-known reference strains of C. jejuni. Overall, the ST-677 CC was recognized as a highly clonal lineage with relatively small differences between the genomes. Among the farm isolates differences were identified mainly in the lengths of the homopolymeric tracts in genes related to the capsule, lipo-oligosaccharide, and flagella. We identified genomic features shared with C. jejuni subsp. doylei, which has also been shown to be associated with bacteremia in humans. These included the degradation of the cytolethal distending toxin operon and similarities between the capsular polysaccharide biosynthesis loci. The phase-variable GDP-mannose 4,6-dehydratase (EC 4.2.1.47) (wcbK, CAMP1649), associated with the capsular polysaccharide biosynthesis locus, may play a central role in ST-677 CC conferring acid and serum resistance during different stages of infection. Homology-based searches revealed several additional novel features and characteristics, including two putative type Vb secretion systems and a novel restriction modification/methyltransferase gene cluster, putatively associated with pathogenesis and niche adaptation.

  17. A general pipeline for the development of anchor markers for comparative genomics in plants

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    Stougaard Jens

    2006-08-01

    Full Text Available Abstract Background Complete or near-complete genomic sequence information is presently only available for a few plant species representing a large phylogenetic diversity among plants. In order to effectively transfer this information to species lacking sequence information, comparative genomic tools need to be developed. Molecular markers permitting cross-species mapping along co-linear genomic regions are central to comparative genomics. These "anchor" markers, defining unique loci in genetic linkage maps of multiple species, are gene-based and possess a number of features that make them relatively sparse. To identify potential anchor marker sequences more efficiently, we have established an automated bioinformatic pipeline that combines multi-species Expressed Sequence Tags (EST and genome sequence data. Results Taking advantage of sequence data from related species, the pipeline identifies evolutionarily conserved sequences that are likely to define unique orthologous loci in most species of the same phylogenetic clade. The key features are the identification of evolutionarily conserved sequences followed by automated design of intron-flanking Polymerase Chain Reaction (PCR primer pairs. Polymorphisms can subsequently be identified by size- or sequence variation of PCR products, amplified from mapping parents or populations. We illustrate our procedure in legumes and grasses and exemplify its application in legumes, where model plant studies and the genome- and EST-sequence data available have a potential impact on the breeding of crop species and on our understanding of the evolution of this large and diverse family. Conclusion We provide a database of 459 candidate anchor loci which have the potential to serve as map anchors in more than 18,000 legume species, a number of which are of agricultural importance. For grasses, the database contains 1335 candidate anchor loci. Based on this database, we have evaluated 76 candidate anchor loci

  18. Systematic discovery of regulatory motifs in Fusarium graminearum by comparing four Fusarium genomes

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    Kistler Corby

    2010-03-01

    Full Text Available Abstract Background Fusarium graminearum (Fg, a major fungal pathogen of cultivated cereals, is responsible for billions of dollars in agriculture losses. There is a growing interest in understanding the transcriptional regulation of this organism, especially the regulation of genes underlying its pathogenicity. The generation of whole genome sequence assemblies for Fg and three closely related Fusarium species provides a unique opportunity for such a study. Results Applying comparative genomics approaches, we developed a computational pipeline to systematically discover evolutionarily conserved regulatory motifs in the promoter, downstream and the intronic regions of Fg genes, based on the multiple alignments of sequenced Fusarium genomes. Using this method, we discovered 73 candidate regulatory motifs in the promoter regions. Nearly 30% of these motifs are highly enriched in promoter regions of Fg genes that are associated with a specific functional category. Through comparison to Saccharomyces cerevisiae (Sc and Schizosaccharomyces pombe (Sp, we observed conservation of transcription factors (TFs, their binding sites and the target genes regulated by these TFs related to pathways known to respond to stress conditions or phosphate metabolism. In addition, this study revealed 69 and 39 conserved motifs in the downstream regions and the intronic regions, respectively, of Fg genes. The top intronic motif is the splice donor site. For the downstream regions, we noticed an intriguing absence of the mammalian and Sc poly-adenylation signals among the list of conserved motifs. Conclusion This study provides the first comprehensive list of candidate regulatory motifs in Fg, and underscores the power of comparative genomics in revealing functional elements among related genomes. The conservation of regulatory pathways among the Fusarium genomes and the two yeast species reveals their functional significance, and provides new insights in their

  19. A genetic linkage map and comparative mapping of the prairie vole (Microtus ochrogaster genome

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    Young Larry J

    2011-07-01

    Full Text Available Abstract Background The prairie vole (Microtus ochrogaster is an emerging rodent model for investigating the genetics, evolution and molecular mechanisms of social behavior. Though a karyotype for the prairie vole has been reported and low-resolution comparative cytogenetic analyses have been done in this species, other basic genetic resources for this species, such as a genetic linkage map, are lacking. Results Here we report the construction of a genome-wide linkage map of the prairie vole. The linkage map consists of 406 markers that are spaced on average every 7 Mb and span an estimated ~90% of the genome. The sex average length of the linkage map is 1707 cM, which, like other Muroid rodent linkage maps, is on the lower end of the length distribution of linkage maps reported to date for placental mammals. Linkage groups were assigned to 19 out of the 26 prairie vole autosomes as well as the X chromosome. Comparative analyses of the prairie vole linkage map based on the location of 387 Type I markers identified 61 large blocks of synteny with the mouse genome. In addition, the results of the comparative analyses revealed a potential elevated rate of inversions in the prairie vole lineage compared to the laboratory mouse and rat. Conclusions A genetic linkage map of the prairie vole has been constructed and represents the fourth genome-wide high-resolution linkage map reported for Muroid rodents and the first for a member of the Arvicolinae sub-family. This resource will advance studies designed to dissect the genetic basis of a variety of social behaviors and other traits in the prairie vole as well as our understanding of genome evolution in the genus Microtus.

  20. Comparative genomics of bacterial and plant folate synthesis and salvage: predictions and validations

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    Noiriel Alexandre

    2007-07-01

    Full Text Available Abstract Background Folate synthesis and salvage pathways are relatively well known from classical biochemistry and genetics but they have not been subjected to comparative genomic analysis. The availability of genome sequences from hundreds of diverse bacteria, and from Arabidopsis thaliana, enabled such an analysis using the SEED database and its tools. This study reports the results of the analysis and integrates them with new and existing experimental data. Results Based on sequence similarity and the clustering, fusion, and phylogenetic distribution of genes, several functional predictions emerged from this analysis. For bacteria, these included the existence of novel GTP cyclohydrolase I and folylpolyglutamate synthase gene families, and of a trifunctional p-aminobenzoate synthesis gene. For plants and bacteria, the predictions comprised the identities of a 'missing' folate synthesis gene (folQ and of a folate transporter, and the absence from plants of a folate salvage enzyme. Genetic and biochemical tests bore out these predictions. Conclusion For bacteria, these results demonstrate that much can be learnt from comparative genomics, even for well-explored primary metabolic pathways. For plants, the findings particularly illustrate the potential for rapid functional assignment of unknown genes that have prokaryotic homologs, by analyzing which genes are associated with the latter. More generally, our data indicate how combined genomic analysis of both plants and prokaryotes can be more powerful than isolated examination of either group alone.

  1. Comparative genomics of xylose-fermenting fungi for enhanced biofuel production

    Energy Technology Data Exchange (ETDEWEB)

    Wohlbach, Dana J.; Kuo, Alan; Sato, Trey K.; Potts, Katlyn M.; Salamov, Asaf A.; LaButti, Kurt M.; Sun, Hui; Clum, Alicia; Pangilinan, Jasmyn L.; Lindquist, Erika A.; Lucas, Susan; Lapidus, Alla; Jin, Mingjie; Gunawan, Christa; Balan, Venkatesh; Dale, Bruce E.; Jeffries, Thomas W.; Zinkel, Robert; Barry, Kerrie W.; Grigoriev, Igor V.; Gasch, Audrey P.

    2011-02-24

    Cellulosic biomass is an abundant and underused substrate for biofuel production. The inability of many microbes to metabolize the pentose sugars abundant within hemicellulose creates specific challenges for microbial biofuel production from cellulosic material. Although engineered strains of Saccharomyces cerevisiae can use the pentose xylose, the fermentative capacity pales in comparison with glucose, limiting the economic feasibility of industrial fermentations. To better understand xylose utilization for subsequent microbial engineering, we sequenced the genomes of two xylose-fermenting, beetle-associated fungi, Spathaspora passalidarum and Candida tenuis. To identify genes involved in xylose metabolism, we applied a comparative genomic approach across 14 Ascomycete genomes, mapping phenotypes and genotypes onto the fungal phylogeny, and measured genomic expression across five Hemiascomycete species with different xylose-consumption phenotypes. This approach implicated many genes and processes involved in xylose assimilation. Several of these genes significantly improved xylose utilization when engineered into S. cerevisiae, demonstrating the power of comparative methods in rapidly identifying genes for biomass conversion while reflecting on fungal ecology.

  2. Comparative genomics of Helicobacter pylori strains of China associated with different clinical outcome.

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    Yuanhai You

    Full Text Available In this study, a whole-genome CombiMatrix Custom oligonucleotide tiling microarray with 90,000 probes covering six sequenced Helicobacter pylori (H. pylori genomes was designed. This microarray was used to compare the genomic profiles of eight unsequenced strains isolated from patients with different gastroduodenal diseases in Heilongjiang province of China. Since significant genomic variation was found among these strains, an additional 76 H. pylori strains associated with different clinical outcomes were isolated from various provinces of China. These strains were tested by polymerase chain reaction to demonstrate this distinction. We identified several highly variable regions in strains associated with gastritis, gastric ulceration, and gastric cancer. These regions are associated with genes involved in the bacterial type I, type II, and type III R-M systems. They were also associated with the virB gene, which lies on the well-studied cag pathogenic island. While previous studies have reported on the diverse genetic characterization of this pathogenic island, in this study, we find that it is conserved in all strains tested by microarray. Moreover, a number of genes involved in the type IV secretion system, which is related to horizontal DNA transfer between H. pylori strains, were identified in the comparative analysis of the strain-specific genes. These findings may provide insight into new biomarkers for the prediction of gastric diseases.

  3. A Comparative Analysis of the Lyve-SET Phylogenomics Pipeline for Genomic Epidemiology of Foodborne Pathogens

    Science.gov (United States)

    Katz, Lee S.; Griswold, Taylor; Williams-Newkirk, Amanda J.; Wagner, Darlene; Petkau, Aaron; Sieffert, Cameron; Van Domselaar, Gary; Deng, Xiangyu; Carleton, Heather A.

    2017-01-01

    Modern epidemiology of foodborne bacterial pathogens in industrialized countries relies increasingly on whole genome sequencing (WGS) techniques. As opposed to profiling techniques such as pulsed-field gel electrophoresis, WGS requires a variety of computational methods. Since 2013, United States agencies responsible for food safety including the CDC, FDA, and USDA, have been performing whole-genome sequencing (WGS) on all Listeria monocytogenes found in clinical, food, and environmental samples. Each year, more genomes of other foodborne pathogens such as Escherichia coli, Campylobacter jejuni, and Salmonella enterica are being sequenced. Comparing thousands of genomes across an entire species requires a fast method with coarse resolution; however, capturing the fine details of highly related isolates requires a computationally heavy and sophisticated algorithm. Most L. monocytogenes investigations employing WGS depend on being able to identify an outbreak clade whose inter-genomic distances are less than an empirically determined threshold. When the difference between a few single nucleotide polymorphisms (SNPs) can help distinguish between genomes that are likely outbreak-associated and those that are less likely to be associated, we require a fine-resolution method. To achieve this level of resolution, we have developed Lyve-SET, a high-quality SNP pipeline. We evaluated Lyve-SET by retrospectively investigating 12 outbreak data sets along with four other SNP pipelines that have been used in outbreak investigation or similar scenarios. To compare these pipelines, several distance and phylogeny-based comparison methods were applied, which collectively showed that multiple pipelines were able to identify most outbreak clusters and strains. Currently in the US PulseNet system, whole genome multi-locus sequence typing (wgMLST) is the preferred primary method for foodborne WGS cluster detection and outbreak investigation due to its ability to name standardized

  4. Comparative Analysis of Genomics and Proteomics in Bacillus thuringiensis 4.0718

    Science.gov (United States)

    Rang, Jie; He, Hao; Wang, Ting; Ding, Xuezhi; Zuo, Mingxing; Quan, Meifang; Sun, Yunjun; Yu, Ziquan; Hu, Shengbiao; Xia, Liqiu

    2015-01-01

    Bacillus thuringiensis is a widely used biopesticide that produced various insecticidal active substances during its life cycle. Separation and purification of numerous insecticide active substances have been difficult because of the relatively short half-life of such substances. On the other hand, substances can be synthetized at different times during development, so samples at different stages have to be studied, further complicating the analysis. A dual genomic and proteomic approach would enhance our ability to identify such substances, and particularily using mass spectrometry-based proteomic methods. The comparative analysis for genomic and proteomic data have showed that not all of the products deduced from the annotated genome could be identified among the proteomic data. For instance, genome annotation results showed that 39 coding sequences in the whole genome were related to insect pathogenicity, including five cry genes. However, Cry2Ab, Cry1Ia, Cytotoxin K, Bacteriocin, Exoenzyme C3 and Alveolysin could not be detected in the proteomic data obtained. The sporulation-related proteins were also compared analysis, results showed that the great majority sporulation-related proteins can be detected by mass spectrometry. This analysis revealed Spo0A~P, SigF, SigE(+), SigK(+) and SigG(+), all known to play an important role in the process of spore formation regulatory network, also were displayed in the proteomic data. Through the comparison of the two data sets, it was possible to infer that some genes were silenced or were expressed at very low levels. For instance, found that cry2Ab seems to lack a functional promoter while cry1Ia may not be expressed due to the presence of transposons. With this comparative study a relatively complete database can be constructed and used to transform hereditary material, thereby prompting the high expression of toxic proteins. A theoretical basis is provided for constructing highly virulent engineered bacteria and for

  5. Comparative analysis of genomics and proteomics in Bacillus thuringiensis 4.0718.

    Directory of Open Access Journals (Sweden)

    Jie Rang

    Full Text Available Bacillus thuringiensis is a widely used biopesticide that produced various insecticidal active substances during its life cycle. Separation and purification of numerous insecticide active substances have been difficult because of the relatively short half-life of such substances. On the other hand, substances can be synthetized at different times during development, so samples at different stages have to be studied, further complicating the analysis. A dual genomic and proteomic approach would enhance our ability to identify such substances, and particularily using mass spectrometry-based proteomic methods. The comparative analysis for genomic and proteomic data have showed that not all of the products deduced from the annotated genome could be identified among the proteomic data. For instance, genome annotation results showed that 39 coding sequences in the whole genome were related to insect pathogenicity, including five cry genes. However, Cry2Ab, Cry1Ia, Cytotoxin K, Bacteriocin, Exoenzyme C3 and Alveolysin could not be detected in the proteomic data obtained. The sporulation-related proteins were also compared analysis, results showed that the great majority sporulation-related proteins can be detected by mass spectrometry. This analysis revealed Spo0A~P, SigF, SigE(+, SigK(+ and SigG(+, all known to play an important role in the process of spore formation regulatory network, also were displayed in the proteomic data. Through the comparison of the two data sets, it was possible to infer that some genes were silenced or were expressed at very low levels. For instance, found that cry2Ab seems to lack a functional promoter while cry1Ia may not be expressed due to the presence of transposons. With this comparative study a relatively complete database can be constructed and used to transform hereditary material, thereby prompting the high expression of toxic proteins. A theoretical basis is provided for constructing highly virulent engineered

  6. Comparative analysis of copy number detection by whole-genome BAC and oligonucleotide array CGH

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    Bejjani Bassem A

    2010-06-01

    Full Text Available Abstract Background Microarray-based comparative genomic hybridization (aCGH is a powerful diagnostic tool for the detection of DNA copy number gains and losses associated with chromosome abnormalities, many of which are below the resolution of conventional chromosome analysis. It has been presumed that whole-genome oligonucleotide (oligo arrays identify more clinically significant copy-number abnormalities than whole-genome bacterial artificial chromosome (BAC arrays, yet this has not been systematically studied in a clinical diagnostic setting. Results To determine the difference in detection rate between similarly designed BAC and oligo arrays, we developed whole-genome BAC and oligonucleotide microarrays and validated them in a side-by-side comparison of 466 consecutive clinical specimens submitted to our laboratory for aCGH. Of the 466 cases studied, 67 (14.3% had a copy-number imbalance of potential clinical significance detectable by the whole-genome BAC array, and 73 (15.6% had a copy-number imbalance of potential clinical significance detectable by the whole-genome oligo array. However, because both platforms identified copy number variants of unclear clinical significance, we designed a systematic method for the interpretation of copy number alterations and tested an additional 3,443 cases by BAC array and 3,096 cases by oligo array. Of those cases tested on the BAC array, 17.6% were found to have a copy-number abnormality of potential clinical significance, whereas the detection rate increased to 22.5% for the cases tested by oligo array. In addition, we validated the oligo array for detection of mosaicism and found that it could routinely detect mosaicism at levels of 30% and greater. Conclusions Although BAC arrays have faster turnaround times, the increased detection rate of oligo arrays makes them attractive for clinical cytogenetic testing.

  7. The pangenome structure of Escherichia coli: comparative genomic analysis of E. coli commensal and pathogenic isolates.

    Science.gov (United States)

    Rasko, David A; Rosovitz, M J; Myers, Garry S A; Mongodin, Emmanuel F; Fricke, W Florian; Gajer, Pawel; Crabtree, Jonathan; Sebaihia, Mohammed; Thomson, Nicholas R; Chaudhuri, Roy; Henderson, Ian R; Sperandio, Vanessa; Ravel, Jacques

    2008-10-01

    Whole-genome sequencing has been skewed toward bacterial pathogens as a consequence of the prioritization of medical and veterinary diseases. However, it is becoming clear that in order to accurately measure genetic variation within and between pathogenic groups, multiple isolates, as well as commensal species, must be sequenced. This study examined the pangenomic content of Escherichia coli. Six distinct E. coli pathovars can be distinguished using molecular or phenotypic markers, but only two of the six pathovars have been subjected to any genome sequencing previously. Thus, this report provides a seminal description of the genomic contents and unique features of three unsequenced pathovars, enterotoxigenic E. coli, enteropathogenic E. coli, and enteroaggregative E. coli. We also determined the first genome sequence of a human commensal E. coli isolate, E. coli HS, which will undoubtedly provide a new baseline from which workers can examine the evolution of pathogenic E. coli. Comparison of 17 E. coli genomes, 8 of which are new, resulted in identification of approximately 2,200 genes conserved in all isolates. We were also able to identify genes that were isolate and pathovar specific. Fewer pathovar-specific genes were identified than anticipated, suggesting that each isolate may have independently developed virulence capabilities. Pangenome calculations indicate that E. coli genomic diversity represents an open pangenome model containing a reservoir of more than 13,000 genes, many of which may be uncharacterized but important virulence factors. This comparative study of the species E. coli, while descriptive, should provide the basis for future functional work on this important group of pathogens.

  8. Comparative genomics of oral isolates of Streptococcus mutans by in silico genome subtraction does not reveal accessory DNA associated with severe early childhood caries.

    Science.gov (United States)

    Argimón, Silvia; Konganti, Kranti; Chen, Hao; Alekseyenko, Alexander V; Brown, Stuart; Caufield, Page W

    2014-01-01

    Comparative genomics is a popular method for the identification of microbial virulence determinants, especially since the sequencing of a large number of whole bacterial genomes from pathogenic and non-pathogenic strains has become relatively inexpensive. The bioinformatics pipelines for comparative genomics usually include gene prediction and annotation and can require significant computer power. To circumvent this, we developed a rapid method for genome-scale in silico subtractive hybridization, based on blastn and independent of feature identification and annotation. Whole genome comparisons by in silico genome subtraction were performed to identify genetic loci specific to Streptococcus mutans strains associated with severe early childhood caries (S-ECC), compared to strains isolated from caries-free (CF) children. The genome similarity of the 20 S. mutans strains included in this study, calculated by Simrank k-mer sharing, ranged from 79.5% to 90.9%, confirming this is a genetically heterogeneous group of strains. We identified strain-specific genetic elements in 19 strains, with sizes ranging from 200 to 39 kb. These elements contained protein-coding regions with functions mostly associated with mobile DNA. We did not, however, identify any genetic loci consistently associated with dental caries, i.e., shared by all the S-ECC strains and absent in the CF strains. Conversely, we did not identify any genetic loci specific with the healthy group. Comparison of previously published genomes from pathogenic and carriage strains of Neisseria meningitidis with our in silico genome subtraction yielded the same set of genes specific to the pathogenic strains, thus validating our method. Our results suggest that S. mutans strains derived from caries active or caries free dentitions cannot be differentiated based on the presence or absence of specific genetic elements. Our in silico genome subtraction method is available as the Microbial Genome Comparison (MGC) tool

  9. Comparative analysis of the complete chloroplast genome sequences in psammophytic Haloxylon species (Amaranthaceae

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    Wenpan Dong

    2016-11-01

    Full Text Available The Haloxylon genus belongs to the Amaranthaceae (formerly Chenopodiaceae family. The small trees or shrubs in this genus are referred to as the King of psammophytic plants, and perform important functions in environmental protection, including wind control and sand fixation in deserts. To better understand these beneficial plants, we sequenced the chloroplast (cp genomes of Haloxylon ammodendron (HA and Haloxylon persicum (HP and conducted comparative genomic analyses on these and two other representative Amaranthaceae species. Similar to other higher plants, we found that the Haloxylon cp genome is a quadripartite, double-stranded, circular DNA molecule of 151,570 bp in HA and 151,586 bp in HP. It contains a pair of inverted repeats (24,171 bp in HA and 24,177 bp in HP that separate the genome into a large single copy region of 84,214 bp in HA and 84,217 bp in HP, and a small single copy region of 19,014 bp in HA and 19,015 bp in HP. Each Haloxylon cp genome contains 112 genes, including 78 coding, 30 tRNA, and four ribosomal RNA genes. We detected 59 different simple sequence repeat loci, including 44 mono-nucleotide, three di-nucleotide, one tri-nucleotide, and 11 tetra-nucleotide repeats. Comparative analysis revealed only 67 mutations between the two species, including 44 substitutions, 23 insertions/deletions, and two micro-inversions. The two inversions, with lengths of 14 and 3 bp, occur in the petA-psbJ intergenic region and rpl16 intron, respectively, and are predicted to form hairpin structures with repeat sequences of 27 and 19 bp, respectively, at the two ends. The ratio of transitions to transversions was 0.76. These results are valuable for future studies on Haloxylon genetic diversity and will enhance our understanding of the phylogenetic evolution of Amaranthaceae.

  10. High-resolution comparative genomic hybridization of inflammatory breast cancer and identification of candidate genes.

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    Ismahane Bekhouche

    Full Text Available BACKGROUND: Inflammatory breast cancer (IBC is an aggressive form of BC poorly defined at the molecular level. We compared the molecular portraits of 63 IBC and 134 non-IBC (nIBC clinical samples. METHODOLOGY/FINDINGS: Genomic imbalances of 49 IBCs and 124 nIBCs were determined using high-resolution array-comparative genomic hybridization, and mRNA expression profiles of 197 samples using whole-genome microarrays. Genomic profiles of IBCs were as heterogeneous as those of nIBCs, and globally relatively close. However, IBCs showed more frequent "complex" patterns and a higher percentage of genes with CNAs per sample. The number of altered regions was similar in both types, although some regions were altered more frequently and/or with higher amplitude in IBCs. Many genes were similarly altered in both types; however, more genes displayed recurrent amplifications in IBCs. The percentage of genes whose mRNA expression correlated with CNAs was similar in both types for the gained genes, but ∼7-fold lower in IBCs for the lost genes. Integrated analysis identified 24 potential candidate IBC-specific genes. Their combined expression accurately distinguished IBCs and nIBCS in an independent validation set, and retained an independent prognostic value in a series of 1,781 nIBCs, reinforcing the hypothesis for a link with IBC aggressiveness. Consistent with the hyperproliferative and invasive phenotype of IBC these genes are notably involved in protein translation, cell cycle, RNA processing and transcription, metabolism, and cell migration. CONCLUSIONS: Our results suggest a higher genomic instability of IBC. We established the first repertory of DNA copy number alterations in this tumor, and provided a list of genes that may contribute to its aggressiveness and represent novel therapeutic targets.

  11. Comparative Genomic Analysis of Rapid Evolution of an Extreme-Drug-Resistant Acinetobacter baumannii Clone

    DEFF Research Database (Denmark)

    Tan, Sean Yang-Yi; Chua, Song Lin; Liu, Yang

    2013-01-01

    , comparative genomics has been employed to analyze the rapid evolution of an EDR Acinetobacter baumannii clone from the intensive care unit (ICU) of Rigshospitalet at Copenhagen. Two resistant A. baumannii strains, 48055 and 53264, were sequentially isolated from two individuals who had been admitted to ICU...... within a 1-month interval. Multilocus sequence typing indicates that these two isolates belonged to ST208. The A. baumannii 53264 strain gained colistin resistance compared with the 48055 strain and became an EDR strain. Genome sequencing indicates that A. baumannii 53264 and 48055 have almost identical...... genomes—61 single-nucleotide polymorphisms (SNPs) were found between them. The A. baumannii 53264 strain was assembled into 130 contigs, with a total length of 3,976,592 bp with 38.93% GC content. The A. baumannii 48055 strain was assembled into 135 contigs, with a total length of 4,049,562 bp with 39...

  12. CMG-Biotools, a Free Workbench for Basic Comparative Microbial Genomics

    DEFF Research Database (Denmark)

    Vesth, Tammi Camilla; Lagesen, Karin; Acar, Öncel;

    2013-01-01

    This paper shows the strength and diverse use of the CMG-biotools system. The system can be installed on a vide range of host operating systems and utilizes as much of the host computer as desired. It allows the user to compare multiple genomes, from various sources using standardized data format...... and intuitive visualizations of results. The examples presented here clearly shows that users with limited computational experience can perform complicated analysis without much training....

  13. Comparative genomics of Toll-like receptor signalling in five species

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    Wu Chunhua

    2009-05-01

    Full Text Available Abstract Background Over the last decade, several studies have identified quantitative trait loci (QTL affecting variation of immune related traits in mammals. Recent studies in humans and mice suggest that part of this variation may be caused by polymorphisms in genes involved in Toll-like receptor (TLR signalling. In this project, we used a comparative approach to investigate the importance of TLR-related genes in comparison with other immunologically relevant genes for resistance traits in five species by associating their genomic location with previously published immune-related QTL regions. Results We report the genomic localisation of TLR1-10 and ten associated signalling molecules in sheep and pig using in-silico and/or radiation hybrid (RH mapping techniques and compare their positions with their annotated homologues in the human, cattle and mouse whole genome sequences. We also report medium-density RH maps for porcine chromosomes 8 and 13. A comparative analysis of the positions of previously published relevant QTLs allowed the identification of homologous regions that are associated with similar health traits in several species and which contain TLR related and other immunologically relevant genes. Additional evidence was gathered by examining relevant gene expression and association studies. Conclusion This comparative genomic approach identified eight genes as potentially causative genes for variations of health related traits. These include susceptibility to clinical mastitis in dairy cattle, general disease resistance in sheep, cattle, humans and mice, and tolerance to protozoan infection in cattle and mice. Four TLR-related genes (TLR1, 6, MyD88, IRF3 appear to be the most likely candidate genes underlying QTL regions which control the resistance to the same or similar pathogens in several species. Further studies are required to investigate the potential role of polymorphisms within these genes.

  14. A glimpse of streptococcal toxic shock syndrome from comparative genomics of S. suis 2 Chinese isolates.

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    Chen Chen

    Full Text Available BACKGROUND: Streptococcus suis serotype 2 (SS2 is an important zoonotic pathogen, causing more than 200 cases of severe human infection worldwide, with the hallmarks of meningitis, septicemia, arthritis, etc. Very recently, SS2 has been recognized as an etiological agent for streptococcal toxic shock syndrome (STSS, which was originally associated with Streptococcus pyogenes (GAS in Streptococci. However, the molecular mechanisms underlying STSS are poorly understood. METHODS AND FINDINGS: To elucidate the genetic determinants of STSS caused by SS2, whole genome sequencing of 3 different Chinese SS2 strains was undertaken. Comparative genomics accompanied by several lines of experiments, including experimental animal infection, PCR assay, and expression analysis, were utilized to further dissect a candidate pathogenicity island (PAI. Here we show, for the first time, a novel molecular insight into Chinese isolates of highly invasive SS2, which caused two large-scale human STSS outbreaks in China. A candidate PAI of approximately 89 kb in length, which is designated 89K and specific for Chinese SS2 virulent isolates, was investigated at the genomic level. It shares the universal properties of PAIs such as distinct GC content, consistent with its pivotal role in STSS and high virulence. CONCLUSIONS: To our knowledge, this is the first PAI candidate from S. suis worldwide. Our finding thus sheds light on STSS triggered by SS2 at the genomic level, facilitates further understanding of its pathogenesis and points to directions of development on some effective strategies to combat highly pathogenic SS2 infections.

  15. Comparative analysis of the domestic cat genome reveals genetic signatures underlying feline biology and domestication.

    Science.gov (United States)

    Montague, Michael J; Li, Gang; Gandolfi, Barbara; Khan, Razib; Aken, Bronwen L; Searle, Steven M J; Minx, Patrick; Hillier, LaDeana W; Koboldt, Daniel C; Davis, Brian W; Driscoll, Carlos A; Barr, Christina S; Blackistone, Kevin; Quilez, Javier; Lorente-Galdos, Belen; Marques-Bonet, Tomas; Alkan, Can; Thomas, Gregg W C; Hahn, Matthew W; Menotti-Raymond, Marilyn; O'Brien, Stephen J; Wilson, Richard K; Lyons, Leslie A; Murphy, William J; Warren, Wesley C

    2014-12-02

    Little is known about the genetic changes that distinguish domestic cat populations from their wild progenitors. Here we describe a high-quality domestic cat reference genome assembly and comparative inferences made with other cat breeds, wildcats, and other mammals. Based upon these comparisons, we identified positively selected genes enriched for genes involved in lipid metabolism that underpin adaptations to a hypercarnivorous diet. We also found positive selection signals within genes underlying sensory processes, especially those affecting vision and hearing in the carnivore lineage. We observed an evolutionary tradeoff between functional olfactory and vomeronasal receptor gene repertoires in the cat and dog genomes, with an expansion of the feline chemosensory system for detecting pheromones at the expense of odorant detection. Genomic regions harboring signatures of natural selection that distinguish domestic cats from their wild congeners are enriched in neural crest-related genes associated with behavior and reward in mouse models, as predicted by the domestication syndrome hypothesis. Our description of a previously unidentified allele for the gloving pigmentation pattern found in the Birman breed supports the hypothesis that cat breeds experienced strong selection on specific mutations drawn from random bred populations. Collectively, these findings provide insight into how the process of domestication altered the ancestral wildcat genome and build a resource for future disease mapping and phylogenomic studies across all members of the Felidae.

  16. Chromosomal Localization of DNA Amplifications in Neuroblastoma Tumors Using cDNA Microarray Comparative Genomic Hybridization

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    Ben Beheshti

    2003-01-01

    Full Text Available Conventional comparative genomic hybridization (CGH profiling of neuroblastomas has identified many genomic aberrations, although the limited resolution has precluded a precise localization of sequences of interest within amplicons. To map high copy number genomic gains in clinically matched stage IV neuroblastomas, CGH analysis using a 19,200-feature cDNA microarray was used. A dedicated (freely available algorithm was developed for rapid in silico determination of chromosomal localizations of microarray cDNA targets, and for generation of an ideogram-type profile of copy number changes. Using these methodologies, novel gene amplifications undetectable by chromosome CGH were identified, and larger MYCN amplicon sizes (in one tumor up to 6 Mb than those previously reported in neuroblastoma were identified. The genes HPCAL1, LPIN1/KIAA0188, NAG, and NSE1/LOC151354 were found to be coamplified with MYCN. To determine whether stage IV primary tumors could be further subclassified based on their genomic copy number profiles, hierarchical clustering was performed. Cluster analysis of microarray CGH data identified three groups: 1 no amplifications evident, 2 a small MYCN amplicon as the only detectable imbalance, and 3 a large MYCN amplicon with additional gene amplifications. Application of CGH to cDNA microarray targets will help to determine both the variation of amplicon size and help better define amplification-dependent and independent pathways of progression in neuroblastoma.

  17. Comparative genome sequencing of drosophila pseudoobscura: Chromosomal, gene and cis-element evolution

    Energy Technology Data Exchange (ETDEWEB)

    Richards, Stephen; Liu, Yue; Bettencourt, Brian R.; Hradecky, Pavel; Letovsky, Stan; Nielsen, Rasmus; Thornton, Kevin; Todd, Melissa J.; Chen, Rui; Meisel, Richard P.; Couronne, Olivier; Hua, Sujun; Smith, Mark A.; Bussemaker, Harmen J.; van Batenburg, Marinus F.; Howells, Sally L.; Scherer, Steven E.; Sodergren, Erica; Matthews, Beverly B.; Crosby, Madeline A.; Schroeder, Andrew J.; Ortiz-Barrientos, Daniel; Rives, Catherine M.; Metzker, Michael L.; Muzny, Donna M.; Scott, Graham; Steffen, David; Wheeler, David A.; Worley, Kim C.; Havlak, Paul; Durbin, K. James; Egan, Amy; Gill, Rachel; Hume, Jennifer; Morgan, Margaret B.; Miner, George; Hamilton, Cerissa; Huang, Yanmei; Waldron, Lenee; Verduzco, Daniel; Blankenburg, Kerstin P.; Dubchak, Inna; Noor, Mohamed A.F.; Anderson, Wyatt; White, Kevin P.; Clark, Andrew G.; Schaeffer, Stephen W.; Gelbart, William; Weinstock, George M.; Gibbs, Richard A.

    2004-04-01

    The genome sequence of a second fruit fly, D. pseudoobscura, presents an opportunity for comparative analysis of a primary model organism D. melanogaster. The vast majority of Drosophila genes have remained on the same arm, but within each arm gene order has been extensively reshuffled leading to the identification of approximately 1300 syntenic blocks. A repetitive sequence is found in the D. pseudoobscura genome at many junctions between adjacent syntenic blocks. Analysis of this novel repetitive element family suggests that recombination between offset elements may have given rise to many paracentric inversions, thereby contributing to the shuffling of gene order in the D. pseudoobscura lineage. Based on sequence similarity and synteny, 10,516 putative orthologs have been identified as a core gene set conserved over 35 My since divergence. Genes expressed in the testes had higher amino acid sequence divergence than the genome wide average consistent with the rapid evolution of sex-specific proteins. Cis-regulatory sequences are more conserved than control sequences between the species but the difference is slight, suggesting that the evolution of cis-regulatory elements is flexible. Overall, a picture of repeat mediated chromosomal rearrangement, and high co-adaptation of both male genes and cis-regulatory sequences emerges as important themes of genome divergence between these species of Drosophila.

  18. Comparative analysis of mitochondrial genomes of five aphid species (Hemiptera: Aphididae and phylogenetic implications.

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    Yuan Wang

    Full Text Available Insect mitochondrial genomes (mitogenomes are of great interest in exploring molecular evolution, phylogenetics and population genetics. Only two mitogenomes have been previously released in the insect group Aphididae, which consists of about 5,000 known species including some agricultural, forestry and horticultural pests. Here we report the complete 16,317 bp mitogenome of Cavariella salicicola and two nearly complete mitogenomes of Aphis glycines and Pterocomma pilosum. We also present a first comparative analysis of mitochondrial genomes of aphids. Results showed that aphid mitogenomes share conserved genomic organization, nucleotide and amino acid composition, and codon usage features. All 37 genes usually present in animal mitogenomes were sequenced and annotated. The analysis of gene evolutionary rate revealed the lowest and highest rates for COI and ATP8, respectively. A unique repeat region exclusively in aphid mitogenomes, which included variable numbers of tandem repeats in a lineage-specific manner, was highlighted for the first time. This region may have a function as another origin of replication. Phylogenetic reconstructions based on protein-coding genes and the stem-loop structures of control regions confirmed a sister relationship between Cavariella and pterocommatines. Current evidence suggest that pterocommatines could be formally transferred into Macrosiphini. Our paper also offers methodological instructions for obtaining other Aphididae mitochondrial genomes.

  19. Comparative evaluation of the genomes of three common Drosophila-associated bacteria.

    Science.gov (United States)

    Petkau, Kristina; Fast, David; Duggal, Aashna; Foley, Edan

    2016-09-15

    Drosophila melanogaster is an excellent model to explore the molecular exchanges that occur between an animal intestine and associated microbes. Previous studies in Drosophila uncovered a sophisticated web of host responses to intestinal bacteria. The outcomes of these responses define critical events in the host, such as the establishment of immune responses, access to nutrients, and the rate of larval development. Despite our steady march towards illuminating the host machinery that responds to bacterial presence in the gut, there are significant gaps in our understanding of the microbial products that influence bacterial association with a fly host. We sequenced and characterized the genomes of three common Drosophila-associated microbes: Lactobacillus plantarum, Lactobacillus brevis and Acetobacter pasteurianus For each species, we compared the genomes of Drosophila-associated strains to the genomes of strains isolated from alternative sources. We found that environmental Lactobacillus strains readily associated with adult Drosophila and were similar to fly isolates in terms of genome organization. In contrast, we identified a strain of A. pasteurianus that apparently fails to associate with adult Drosophila due to an inability to grow on fly nutrient food. Comparisons between association competent and incompetent A. pasteurianus strains identified a short list of candidate genes that may contribute to survival on fly medium. Many of the gene products unique to fly-associated strains have established roles in the stabilization of host-microbe interactions. These data add to a growing body of literature that examines the microbial perspective of host-microbe relationships.

  20. LegumeIP: an integrative database for comparative genomics and transcriptomics of model legumes.

    Science.gov (United States)

    Li, Jun; Dai, Xinbin; Liu, Tingsong; Zhao, Patrick Xuechun

    2012-01-01

    Legumes play a vital role in maintaining the nitrogen cycle of the biosphere. They conduct symbiotic nitrogen fixation through endosymbiotic relationships with bacteria in root nodules. However, this and other characteristics of legumes, including mycorrhization, compound leaf development and profuse secondary metabolism, are absent in the typical model plant Arabidopsis thaliana. We present LegumeIP (http://plantgrn.noble.org/LegumeIP/), an integrative database for comparative genomics and transcriptomics of model legumes, for studying gene function and genome evolution in legumes. LegumeIP compiles gene and gene family information, syntenic and phylogenetic context and tissue-specific transcriptomic profiles. The database holds the genomic sequences of three model legumes, Medicago truncatula, Glycine max and Lotus japonicus plus two reference plant species, A. thaliana and Populus trichocarpa, with annotations based on UniProt, InterProScan, Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes databases. LegumeIP also contains large-scale microarray and RNA-Seq-based gene expression data. Our new database is capable of systematic synteny analysis across M. truncatula, G. max, L. japonicas and A. thaliana, as well as construction and phylogenetic analysis of gene families across the five hosted species. Finally, LegumeIP provides comprehensive search and visualization tools that enable flexible queries based on gene annotation, gene family, synteny and relative gene expression.

  1. DNA Slippage Occurs at Microsatellite Loci without Minimal Threshold Length in Humans: A Comparative Genomic Approach

    Science.gov (United States)

    Leclercq, Sébastien; Rivals, Eric; Jarne, Philippe

    2010-01-01

    The dynamics of microsatellite, or short tandem repeats (STRs), is well documented for long, polymorphic loci, but much less is known for shorter ones. For example, the issue of a minimum threshold length for DNA slippage remains contentious. Model-fitting methods have generally concluded that slippage only occurs over a threshold length of about eight nucleotides, in contradiction with some direct observations of tandem duplications at shorter repeated sites. Using a comparative analysis of the human and chimpanzee genomes, we examined the mutation patterns at microsatellite loci with lengths as short as one period plus one nucleotide. We found that the rates of tandem insertions and deletions at microsatellite loci strongly deviated from background rates in other parts of the human genome and followed an exponential increase with STR size. More importantly, we detected no lower threshold length for slippage. The rate of tandem duplications at unrepeated sites was higher than expected from random insertions, providing evidence for genome-wide action of indel slippage (an alternative mechanism generating tandem repeats). The rate of point mutations adjacent to STRs did not differ from that estimated elsewhere in the genome, except around dinucleotide loci. Our results suggest that the emergence of STR depends on DNA slippage, indel slippage, and point mutations. We also found that the dynamics of tandem insertions and deletions differed in both rates and size at which these mutations take place. We discuss these results in both evolutionary and mechanistic terms. PMID:20624737

  2. Genome-level identification, gene expression, and comparative analysis of porcine ß-defensin genes

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    Choi Min-Kyeung

    2012-11-01

    Full Text Available Abstract Background Beta-defensins (β-defensins are innate immune peptides with evolutionary conservation across a wide range of species and has been suggested to play important roles in innate immune reactions against pathogens. However, the complete β-defensin repertoire in the pig has not been fully addressed. Result A BLAST analysis was performed against the available pig genomic sequence in the NCBI database to identify β-defensin-related sequences using previously reported β-defensin sequences of pigs, humans, and cattle. The porcine β-defensin gene clusters were mapped to chromosomes 7, 14, 15 and 17. The gene expression analysis of 17 newly annotated porcine β-defensin genes across 15 tissues using semi-quantitative reverse transcription polymerase chain reaction (RT-PCR showed differences in their tissue distribution, with the kidney and testis having the largest pBD expression repertoire. We also analyzed single nucleotide polymorphisms (SNPs in the mature peptide region of pBD genes from 35 pigs of 7 breeds. We found 8 cSNPs in 7 pBDs. Conclusion We identified 29 porcine β-defensin (pBD gene-like sequences, including 17 unreported pBDs in the porcine genome. Comparative analysis of β-defensin genes in the pig genome with those in human and cattle genomes showed structural conservation of β-defensin syntenic regions among these species.

  3. What can comparative genomics tell us about species concepts in the genus Aspergillus?

    Energy Technology Data Exchange (ETDEWEB)

    Rokas, Antonis; payne, gary; Federova, Natalie D.; Baker, Scott E.; Machida, Masa; yu, Jiujiang; georgianna, D. R.; Dean, Ralph A.; Bhatnagar, Deepak; Cleveland, T. E.; Wortman, Jennifer R.; Maiti, R.; Joardar, V.; Amedeo, Paolo; Denning, David W.; Nierman, William C.

    2007-12-15

    Understanding the nature of species" boundaries is a fundamental question in evolutionary biology. The availability of genomes from several species of the genus Aspergillus allows us for the first time to examine the demarcation of fungal species at the whole-genome level. Here, we examine four case studies, two of which involve intraspecific comparisons, whereas the other two deal with interspecific genomic comparisons between closely related species. These four comparisons reveal significant variation in the nature of species boundaries across Aspergillus. For example, comparisons between A. fumigatus and Neosartorya fischeri (the teleomorph of A. fischerianus) and between A. oryzae and A. flavus suggest that measures of sequence similarity and species-specific genes are significantly higher for the A. fumigatus - N. fischeri pair. Importantly, the values obtained from the comparison between A. oryzae and A. flavus are remarkably similar to those obtained from an intra-specific comparison of A. fumigatus strains, giving support to the proposal that A. oryzae represents a distinct ecotype of A. flavus and not a distinct species. We argue that genomic data can aid Aspergillus taxonomy by serving as a source of novel and unprecedented amounts of comparative data, as a resource for the development of additional diagnostic tools, and finally as a knowledge database about the biological differences between strains and species.

  4. Comparative analysis of field-isolate and monkey-adapted Plasmodium vivax genomes.

    Science.gov (United States)

    Chan, Ernest R; Barnwell, John W; Zimmerman, Peter A; Serre, David

    2015-03-01

    Significant insights into the biology of Plasmodium vivax have been gained from the ability to successfully adapt human infections to non-human primates. P. vivax strains grown in monkeys serve as a renewable source of parasites for in vitro and ex vivo experimental studies and functional assays, or for studying in vivo the relapse characteristics, mosquito species compatibilities, drug susceptibility profiles or immune responses towards potential vaccine candidates. Despite the importance of these studies, little is known as to how adaptation to a different host species may influence the genome of P. vivax. In addition, it is unclear whether these monkey-adapted strains consist of a single clonal population of parasites or if they retain the multiclonal complexity commonly observed in field isolates. Here we compare the genome sequences of seven P. vivax strains adapted to New World monkeys with those of six human clinical isolates collected directly in the field. We show that the adaptation of P. vivax parasites to monkey hosts, and their subsequent propagation, did not result in significant modifications of their genome sequence and that these monkey-adapted strains recapitulate the genomic diversity of field isolates. Our analyses also reveal that these strains are not always genetically homogeneous and should be analyzed cautiously. Overall, our study provides a framework to better leverage this important research material and fully utilize this resource for improving our understanding of P. vivax biology.

  5. Comparative genomic and proteomic analysis of high grade glioma primary cultures and matched tumor in situ.

    LENUS (Irish Health Repository)

    Howley, R

    2012-10-15

    Developing targeted therapies for high grade gliomas (HGG), the most common primary brain tumor in adults, relies largely on glioma cultures. However, it is unclear if HGG tumorigenic signaling pathways are retained under in-vitro conditions. Using array comparative genomic hybridization and immunohistochemical profiling, we contrasted the epidermal and platelet-derived growth factor receptor (EGFR\\/PDGFR) in-vitro pathway status of twenty-six primary HGG cultures with the pathway status of their original HGG biopsies. Genomic gains or amplifications were lost during culturing while genomic losses were more likely to be retained. Loss of EGFR amplification was further verified immunohistochemically when EGFR over expression was decreased in the majority of cultures. Conversely, PDGFRα and PDGFRβ were more abundantly expressed in primary cultures than in the original tumor (p<0.05). Despite these genomic and proteomic differences, primary HGG cultures retained key aspects of dysregulated tumorigenic signaling. Both in-vivo and in-vitro the presence of EGFR resulted in downstream activation of P70s6K while reduced downstream activation was associated with the presence of PDGFR and the tumor suppressor, PTEN. The preserved pathway dysregulation make this glioma model suitable for further studies of glioma tumorigenesis, however individual culture related differences must be taken into consideration when testing responsiveness to chemotherapeutic agents.

  6. Comparative Analysis of 35 Basidiomycete Genomes Reveals Diversity and Uniqueness of the Phylum

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Robert; Salamov, Asaf; Otillar, Robert; Fagnan, Kirsten; Boussau, Bastien; Brown, Daren; Henrissat, Bernard; Levasseur, Anthony; Held, Benjamin; Nagy, Laszlo; Floudas, Dimitris; Morin, Emmanuelle; Manning, Gerard; Baker, Scott; Martin, Francis; Blanchette, Robert; Hibbett, David; Grigoriev, Igor V.

    2013-03-11

    Fungi of the phylum Basidiomycota (basidiomycetes), make up some 37percent of the described fungi, and are important in forestry, agriculture, medicine, and bioenergy. This diverse phylum includes symbionts, pathogens, and saprobes including wood decaying fungi. To better understand the diversity of this phylum we compared the genomes of 35 basidiomycete fungi including 6 newly sequenced genomes. The genomes of basidiomycetes span extremes of genome size, gene number, and repeat content. A phylogenetic tree of Basidiomycota was generated using the Phyldog software, which uses all available protein sequence data to simultaneously infer gene and species trees. Analysis of core genes reveals that some 48percent of basidiomycete proteins are unique to the phylum with nearly half of those (22percent) comprising proteins found in only one organism. Phylogenetic patterns of plant biomass-degrading genes suggest a continuum rather than a sharp dichotomy between the white rot and brown rot modes of wood decay among the members of Agaricomycotina subphylum. There is a correlation of the profile of certain gene families to nutritional mode in Agaricomycotina. Based on phylogenetically-informed PCA analysis of such profiles, we predict that that Botryobasidium botryosum and Jaapia argillacea have properties similar to white rot species, although neither has liginolytic class II fungal peroxidases. Furthermore, we find that both fungi exhibit wood decay with white rot-like characteristics in growth assays. Analysis of the rate of discovery of proteins with no or few homologs suggests the high value of continued sequencing of basidiomycete fungi.

  7. UniPrimer: A Web-Based Primer Design Tool for Comparative Analyses of Primate Genomes

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    Nomin Batnyam

    2012-01-01

    Full Text Available Whole genome sequences of various primates have been released due to advanced DNA-sequencing technology. A combination of computational data mining and the polymerase chain reaction (PCR assay to validate the data is an excellent method for conducting comparative genomics. Thus, designing primers for PCR is an essential procedure for a comparative analysis of primate genomes. Here, we developed and introduced UniPrimer for use in those studies. UniPrimer is a web-based tool that designs PCR- and DNA-sequencing primers. It compares the sequences from six different primates (human, chimpanzee, gorilla, orangutan, gibbon, and rhesus macaque and designs primers on the conserved region across species. UniPrimer is linked to RepeatMasker, Primer3Plus, and OligoCalc softwares to produce primers with high accuracy and UCSC In-Silico PCR to confirm whether the designed primers work. To test the performance of UniPrimer, we designed primers on sample sequences using UniPrimer and manually designed primers for the same sequences. The comparison of the two processes showed that UniPrimer was more effective than manual work in terms of saving time and reducing errors.

  8. Next Generation Semiconductor Based Sequencing of the Donkey (Equus asinus Genome Provided Comparative Sequence Data against the Horse Genome and a Few Millions of Single Nucleotide Polymorphisms.

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    Francesca Bertolini

    Full Text Available Few studies investigated the donkey (Equus asinus at the whole genome level so far. Here, we sequenced the genome of two male donkeys using a next generation semiconductor based sequencing platform (the Ion Proton sequencer and compared obtained sequence information with the available donkey draft genome (and its Illumina reads from which it was originated and with the EquCab2.0 assembly of the horse genome. Moreover, the Ion Torrent Personal Genome Analyzer was used to sequence reduced representation libraries (RRL obtained from a DNA pool including donkeys of different breeds (Grigio Siciliano, Ragusano and Martina Franca. The number of next generation sequencing reads aligned with the EquCab2.0 horse genome was larger than those aligned with the draft donkey genome. This was due to the larger N50 for contigs and scaffolds of the horse genome. Nucleotide divergence between E. caballus and E. asinus was estimated to be ~ 0.52-0.57%. Regions with low nucleotide divergence were identified in several autosomal chromosomes and in the whole chromosome X. These regions might be evolutionally important in equids. Comparing Y-chromosome regions we identified variants that could be useful to track donkey paternal lineages. Moreover, about 4.8 million of single nucleotide polymorphisms (SNPs in the donkey genome were identified and annotated combining sequencing data from Ion Proton (whole genome sequencing and Ion Torrent (RRL runs with Illumina reads. A higher density of SNPs was present in regions homologous to horse chromosome 12, in which several studies reported a high frequency of copy number variants. The SNPs we identified constitute a first resource useful to describe variability at the population genomic level in E. asinus and to establish monitoring systems for the conservation of donkey genetic resources.

  9. Next Generation Semiconductor Based Sequencing of the Donkey (Equus asinus) Genome Provided Comparative Sequence Data against the Horse Genome and a Few Millions of Single Nucleotide Polymorphisms.

    Science.gov (United States)

    Bertolini, Francesca; Scimone, Concetta; Geraci, Claudia; Schiavo, Giuseppina; Utzeri, Valerio Joe; Chiofalo, Vincenzo; Fontanesi, Luca

    2015-01-01

    Few studies investigated the donkey (Equus asinus) at the whole genome level so far. Here, we sequenced the genome of two male donkeys using a next generation semiconductor based sequencing platform (the Ion Proton sequencer) and compared obtained sequence information with the available donkey draft genome (and its Illumina reads from which it was originated) and with the EquCab2.0 assembly of the horse genome. Moreover, the Ion Torrent Personal Genome Analyzer was used to sequence reduced representation libraries (RRL) obtained from a DNA pool including donkeys of different breeds (Grigio Siciliano, Ragusano and Martina Franca). The number of next generation sequencing reads aligned with the EquCab2.0 horse genome was larger than those aligned with the draft donkey genome. This was due to the larger N50 for contigs and scaffolds of the horse genome. Nucleotide divergence between E. caballus and E. asinus was estimated to be ~ 0.52-0.57%. Regions with low nucleotide divergence were identified in several autosomal chromosomes and in the whole chromosome X. These regions might be evolutionally important in equids. Comparing Y-chromosome regions we identified variants that could be useful to track donkey paternal lineages. Moreover, about 4.8 million of single nucleotide polymorphisms (SNPs) in the donkey genome were identified and annotated combining sequencing data from Ion Proton (whole genome sequencing) and Ion Torrent (RRL) runs with Illumina reads. A higher density of SNPs was present in regions homologous to horse chromosome 12, in which several studies reported a high frequency of copy number variants. The SNPs we identified constitute a first resource useful to describe variability at the population genomic level in E. asinus and to establish monitoring systems for the conservation of donkey genetic resources.

  10. Genomic sequencing and comparative analysis of Epstein-Barr virus genome isolated from primary nasopharyngeal carcinoma biopsy.

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    Hin Kwok

    Full Text Available Whether certain Epstein-Barr virus (EBV strains are associated with pathogenesis of nasopharyngeal carcinoma (NPC is still an unresolved question. In the present study, EBV genome contained in a primary NPC tumor biopsy was amplified by Polymerase Chain Reaction (PCR, and sequenced using next-generation (Illumina and conventional dideoxy-DNA sequencing. The EBV genome, designated HKNPC1 (Genbank accession number JQ009376 is a type 1 EBV of approximately 171.5 kb. The virus appears to be a uniform strain in line with accepted monoclonal nature of EBV in NPC but is heterogeneous at 172 nucleotide positions. Phylogenetic analysis with the four published EBV strains, B95-8, AG876, GD1, and GD2, indicated HKNPC1 was more closely related to the Chinese NPC patient-derived strains, GD1 and GD2. HKNPC1 contains 1,589 single nucleotide variations (SNVs and 132 insertions or deletions (indels in comparison to the reference EBV sequence (accession number NC007605. When compared to AG876, a strain derived from Ghanaian Burkitt's lymphoma, we found 322 SNVs, of which 76 were non-synonymous SNVs and were shared amongst the Chinese GD1, GD2 and HKNPC1 isolates. We observed 88 non-synonymous SNVs shared only by HKNPC1 and GD2, the only other NPC tumor-derived strain reported thus far. Non-synonymous SNVs were mainly found in the latent, tegument and glycoprotein genes. The same point mutations were found in glycoprotein (BLLF1 and BALF4 genes of GD1, GD2 and HKNPC1 strains and might affect cell type specific binding. Variations in LMP1 and EBNA3B epitopes and mutations in Cp (11404 C>T and Qp (50134 G>C found in GD1, GD2 and HKNPC1 could potentially affect CD8(+ T cell recognition and latent gene expression pattern in NPC, respectively. In conclusion, we showed that whole genome sequencing of EBV in NPC may facilitate discovery of previously unknown variations of pathogenic significance.

  11. The complete nucleotide sequence and multipartite organization of the tobacco mitochondrial genome: comparative analysis of mitochondrial genomes in higher plants.

    Science.gov (United States)

    Sugiyama, Y; Watase, Y; Nagase, M; Makita, N; Yagura, S; Hirai, A; Sugiura, M

    2005-02-01

    Tobacco is a valuable model system for investigating the origin of mitochondrial DNA (mtDNA) in amphidiploid plants and studying the genetic interaction between mitochondria and chloroplasts in the various functions of the plant cell. As a first step, we have determined the complete mtDNA sequence of Nicotiana tabacum. The mtDNA of N. tabacum can be assumed to be a master circle (MC) of 430,597 bp. Sequence comparison of a large number of clones revealed that there are four classes of boundaries derived from homologous recombination, which leads to a multipartite organization with two MCs and six subgenomic circles. The mtDNA of N. tabacum contains 36 protein-coding genes, three ribosomal RNA genes and 21 tRNA genes. Among the first class, we identified the genes rps1 and psirps14, which had previously been thought to be absent in tobacco mtDNA on the basis of Southern analysis. Tobacco mtDNA was compared with those of Arabidopsis thaliana, Beta vulgaris, Oryza sativa and Brassica napus. Since repeated sequences show no homology to each other among the five angiosperms, it can be supposed that these were independently acquired by each species during the evolution of angiosperms. The gene order and the sequences of intergenic spacers in mtDNA also differ widely among the five angiosperms, indicating multiple reorganizations of genome structure during the evolution of higher plants. Among the conserved genes, the same potential conserved nonanucleotide-motif-type promoter could only be postulated for rrn18-rrn5 in four of the dicotyledonous plants, suggesting that a coding sequence does not necessarily move with the promoter upon reorganization of the mitochondrial genome.

  12. Shared Y chromosome repetitive DNA sequences in stallion and donkey as visualized using whole-genomic comparative hybridization

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    R. Mezzanotte

    2010-01-01

    Full Text Available The genome of stallion (Spanish breed and donkey (Spanish endemic Zamorano-Leonés were compared using whole comparative genomic in situ hybridization (W-CGH technique, with special reference to the variability observed in the Y chromosome. Results show that these diverging genomes still share some highly repetitive DNA families localized in pericentromeric regions and, in the particular case of the Y chromosome, a sub-family of highly repeated DNA sequences, greatly expanded in the donkey genome, accounts for a large part of the chromatin in the stallion Y chromosome.

  13. Array comparative genomic hybridization analysis of Trichoderma reesei strains with enhanced cellulase production properties

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    Penttilä Merja

    2010-07-01

    Full Text Available Abstract Background Trichoderma reesei is the main industrial producer of cellulases and hemicellulases that are used to depolymerize biomass in a variety of biotechnical applications. Many of the production strains currently in use have been generated by classical mutagenesis. In this study we characterized genomic alterations in high-producing mutants of T. reesei by high-resolution array comparative genomic hybridization (aCGH. Our aim was to obtain genome-wide information which could be utilized for better understanding of the mechanisms underlying efficient cellulase production, and would enable targeted genetic engineering for improved production of proteins in general. Results We carried out an aCGH analysis of four high-producing strains (QM9123, QM9414, NG14 and Rut-C30 using the natural isolate QM6a as a reference. In QM9123 and QM9414 we detected a total of 44 previously undocumented mutation sites including deletions, chromosomal translocation breakpoints and single nucleotide mutations. In NG14 and Rut-C30 we detected 126 mutations of which 17 were new mutations not documented previously. Among these new mutations are the first chromosomal translocation breakpoints identified in NG14 and Rut-C30. We studied the effects of two deletions identified in Rut-C30 (a deletion of 85 kb in the scaffold 15 and a deletion in a gene encoding a transcription factor on cellulase production by constructing knock-out strains in the QM6a background. Neither the 85 kb deletion nor the deletion of the transcription factor affected cellulase production. Conclusions aCGH analysis identified dozens of mutations in each strain analyzed. The resolution was at the level of single nucleotide mutation. High-density aCGH is a powerful tool for genome-wide analysis of organisms with small genomes e.g. fungi, especially in studies where a large set of interesting strains is analyzed.

  14. Comparative genomics and proteomics of Helicobacter mustelae, an ulcerogenic and carcinogenic gastric pathogen

    LENUS (Irish Health Repository)

    O'Toole, Paul W

    2010-03-10

    Abstract Background Helicobacter mustelae causes gastritis, ulcers and gastric cancer in ferrets and other mustelids. H. mustelae remains the only helicobacter other than H. pylori that causes gastric ulceration and cancer in its natural host. To improve understanding of H. mustelae pathogenesis, and the ulcerogenic and carcinogenic potential of helicobacters in general, we sequenced the H. mustelae genome, and identified 425 expressed proteins in the envelope and cytosolic proteome. Results The H. mustelae genome lacks orthologs of major H. pylori virulence factors including CagA, VacA, BabA, SabA and OipA. However, it encodes ten autotransporter surface proteins, seven of which were detected in the expressed proteome, and which, except for the Hsr protein, are of unknown function. There are 26 putative outer membrane proteins in H. mustelae, some of which are most similar to the Hof proteins of H. pylori. Although homologs of putative virulence determinants of H. pylori (NapA, plasminogen adhesin, collagenase) and Campylobacter jejuni (CiaB, Peb4a) are present in the H. mustelae genome, it also includes a distinct complement of virulence-related genes including a haemagglutinin\\/haemolysin protein, and a glycosyl transferase for producing blood group A\\/B on its lipopolysaccharide. The most highly expressed 264 proteins in the cytosolic proteome included many corresponding proteins from H. pylori, but the rank profile in H. mustelae was distinctive. Of 27 genes shown to be essential for H. pylori colonization of the gerbil, all but three had orthologs in H. mustelae, identifying a shared set of core proteins for gastric persistence. Conclusions The determination of the genome sequence and expressed proteome of the ulcerogenic species H mustelae provides a comparative model for H. pylori to investigate bacterial gastric carcinogenesis in mammals, and to suggest ways whereby cag minus H. pylori strains might cause ulceration and cancer. The genome sequence was

  15. Comparative genomics and proteomics of Helicobacter mustelae, an ulcerogenic and carcinogenic gastric pathogen

    Directory of Open Access Journals (Sweden)

    McMullan Geoff

    2010-03-01

    Full Text Available Abstract Background Helicobacter mustelae causes gastritis, ulcers and gastric cancer in ferrets and other mustelids. H. mustelae remains the only helicobacter other than H. pylori that causes gastric ulceration and cancer in its natural host. To improve understanding of H. mustelae pathogenesis, and the ulcerogenic and carcinogenic potential of helicobacters in general, we sequenced the H. mustelae genome, and identified 425 expressed proteins in the envelope and cytosolic proteome. Results The H. mustelae genome lacks orthologs of major H. pylori virulence factors including CagA, VacA, BabA, SabA and OipA. However, it encodes ten autotransporter surface proteins, seven of which were detected in the expressed proteome, and which, except for the Hsr protein, are of unknown function. There are 26 putative outer membrane proteins in H. mustelae, some of which are most similar to the Hof proteins of H. pylori. Although homologs of putative virulence determinants of H. pylori (NapA, plasminogen adhesin, collagenase and Campylobacter jejuni (CiaB, Peb4a are present in the H. mustelae genome, it also includes a distinct complement of virulence-related genes including a haemagglutinin/haemolysin protein, and a glycosyl transferase for producing blood group A/B on its lipopolysaccharide. The most highly expressed 264 proteins in the cytosolic proteome included many corresponding proteins from H. pylori, but the rank profile in H. mustelae was distinctive. Of 27 genes shown to be essential for H. pylori colonization of the gerbil, all but three had orthologs in H. mustelae, identifying a shared set of core proteins for gastric persistence. Conclusions The determination of the genome sequence and expressed proteome of the ulcerogenic species H mustelae provides a comparative model for H. pylori to investigate bacterial gastric carcinogenesis in mammals, and to suggest ways whereby cag minus H. pylori strains might cause ulceration and cancer. The genome

  16. Use of methylation filtration and Cot fractionation for analysis of genome composition and comparative genomics in bread wheat

    Institute of Scientific and Technical Information of China (English)

    Rajib Bandopadhyay; Sachin Rustgi; Rajat Kanti Chaudhuri; Paramjit Khurana; Jitendra Paul Khurana; Akhilesh Kumar Tyagi; Harindra Singh Balyan; Andreas Houben; Pushpendra Kumar Gupta

    2011-01-01

    We investigated the compositional and structural differences in sequences derived from different fractions of wheat genomic DNA obtained using methylation filtration and Cot fractionation. Comparative analysis of these sequences revealed large compositional and structural variations in terms of GC content, different structural elements including repeat sequences (e.g., transposable elements and simple sequence repeats),protein coding genes, and non-coding RNA genes. A correlation between methylation status [determined on the basis of selective inclusion/exclusion in methylation-filtered (MF) library]of different repeat elements and expression level was observed. The expression levels were determined by comparing MF sequences with expressed sequence tags (ESTs) available in the public domain. Only a limited overlap among MF,high Cot (HC), and ESTs was observed, suggesting that these sequences may largely either represent the low-copy non-transcribed sequences or include genes with low expression levels. Thus, these results indicated a need to study MF and HC sequences along with ESTs to fully appreciate complexity of wheat gene space.

  17. Comparative genome sequence analysis of Choristoneura occidentalis Freeman and C. rosaceana Harris (Lepidoptera: Tortricidae alphabaculoviruses.

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    David K Thumbi

    Full Text Available The complete genome sequences of Choristoneura occidentalis and C. rosaceana nucleopolyhedroviruses (ChocNPV and ChroNPV, respectively (Baculoviridae: Alphabaculovirus were determined and compared with each other and with those of other baculoviruses, including the genome of the closely related C. fumiferana NPV (CfMNPV. The ChocNPV genome was 128,446 bp in length (1147 bp smaller than that of CfMNPV, had a G+C content of 50.1%, and contained 148 open reading frames (ORFs. In comparison, the ChroNPV genome was 129,052 bp in length, had a G+C content of 48.6% and contained 149 ORFs. ChocNPV and ChroNPV shared 144 ORFs in common, and had a 77% sequence identity with each other and 96.5% and 77.8% sequence identity, respectively, with CfMNPV. Five homologous regions (hrs, with sequence similarities to those of CfMNPV, were identified in ChocNPV, whereas the ChroNPV genome contained three hrs featuring up to 14 repeats. Both genomes encoded three inhibitors of apoptosis (IAP-1, IAP-2, and IAP-3, as reported for CfMNPV, and the ChocNPV IAP-3 gene represented the most divergent functional region of this genome relative to CfMNPV. Two ORFs were unique to ChocNPV, and four were unique to ChroNPV. ChroNPV ORF chronpv38 is a eukaryotic initiation factor 5 (eIF-5 homolog that has also been identified in the C. occidentalis granulovirus (ChocGV and is believed to be the product of horizontal gene transfer from the host. Based on levels of sequence identity and phylogenetic analysis, both ChocNPV and ChroNPV fall within group I alphabaculoviruses, where ChocNPV appears to be more closely related to CfMNPV than does ChroNPV. Our analyses suggest that it may be appropriate to consider ChocNPV and CfMNPV as variants of the same virus species.

  18. Comparative Genome Analysis Provides Insights into the Pathogenicity of Flavobacterium psychrophilum

    DEFF Research Database (Denmark)

    Castillo, Daniel; Christiansen, Rói Hammershaimb; Dalsgaard, Inger

    2016-01-01

    to describe the F. psychrophilum pan-genome and to examine virulence factors, prophages, CRISPR arrays, and genomic islands present in the genomes. Analysis of the genomic DNA sequences were complemented with selected phenotypic characteristics of the strains. The pan genome analysis showed that F...

  19. Comparative genomics provide a rapid detection ofFusarium oxysporum f. sp.conglutinans

    Institute of Scientific and Technical Information of China (English)

    LING Jian; ZHANG Ji-xiang; ZENG Feng; CAO Yue-xia; XIE Bing-yan; YANG Yu-hong

    2016-01-01

    Fusarium oxysporumf. sp. conglutinans(Foc) is the causal agent ofFusarium wilt disease ofBrassica oleracea. A rapid, accurate, and reliable method to detect and identify plant pathogens is vitaly important to integrated disease management. In this study, using a comparative genome analysis amongFusarium oxysporum (Fo), we developed aFoc-speciifc primer set (Focs-1/Focs-2) and established a multiplex-PCR assay. In the assay, the Focs-1/Focs-2 and universal primers for Fusariumspecies(W106R/F106S) could be used to detectFoc isolates in a single PCR reaction. With the optimized PCR parameters, the multiplex-PCR assay showed a high speciifcity for detectingFoc and was very sensitive to detect as little as 100 pg of pureFoc genomic DNA or 1000 spores in 1 g of twice-autoclaved soil. We also demonstrated thatFoc isolates were easily detected from infected plant tissues, as wel as from natural ifeld soils, using the multiplex-PCR assay. To our knowledge, this is a ifrst report on detectionFo by comparative genomic method.

  20. Comparative genome-scale reconstruction of gapless metabolic networks for present and ancestral species.

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    Esa Pitkänen

    2014-02-01

    Full Text Available We introduce a novel computational approach, CoReCo, for comparative metabolic reconstruction and provide genome-scale metabolic network models for 49 important fungal species. Leveraging on the exponential growth in sequenced genome availability, our method reconstructs genome-scale gapless metabolic networks simultaneously for a large number of species by integrating sequence data in a probabilistic framework. High reconstruction accuracy is demonstrated by comparisons to the well-curated Saccharomyces cerevisiae consensus model and large-scale knock-out experiments. Our comparative approach is particularly useful in scenarios where the quality of available sequence data is lacking, and when reconstructing evolutionary distant species. Moreover, the reconstructed networks are fully carbon mapped, allowing their use in 13C flux analysis. We demonstrate the functionality and usability of the reconstructed fungal models with computational steady-state biomass production experiment, as these fungi include some of the most important production organisms in industrial biotechnology. In contrast to many existing reconstruction techniques, only minimal manual effort is required before the reconstructed models are usable in flux balance experiments. CoReCo is available at http://esaskar.github.io/CoReCo/.

  1. Comparative Genome-Scale Reconstruction of Gapless Metabolic Networks for Present and Ancestral Species

    Science.gov (United States)

    Pitkänen, Esa; Jouhten, Paula; Hou, Jian; Syed, Muhammad Fahad; Blomberg, Peter; Kludas, Jana; Oja, Merja; Holm, Liisa; Penttilä, Merja; Rousu, Juho; Arvas, Mikko

    2014-01-01

    We introduce a novel computational approach, CoReCo, for comparative metabolic reconstruction and provide genome-scale metabolic network models for 49 important fungal species. Leveraging on the exponential growth in sequenced genome availability, our method reconstructs genome-scale gapless metabolic networks simultaneously for a large number of species by integrating sequence data in a probabilistic framework. High reconstruction accuracy is demonstrated by comparisons to the well-curated Saccharomyces cerevisiae consensus model and large-scale knock-out experiments. Our comparative approach is particularly useful in scenarios where the quality of available sequence data is lacking, and when reconstructing evolutionary distant species. Moreover, the reconstructed networks are fully carbon mapped, allowing their use in 13C flux analysis. We demonstrate the functionality and usability of the reconstructed fungal models with computational steady-state biomass production experiment, as these fungi include some of the most important production organisms in industrial biotechnology. In contrast to many existing reconstruction techniques, only minimal manual effort is required before the reconstructed models are usable in flux balance experiments. CoReCo is available at http://esaskar.github.io/CoReCo/. PMID:24516375

  2. Comparative genomics of 2009 seasonal plague (Yersinia pestis in New Mexico.

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    Henry S Gibbons

    Full Text Available Plague disease caused by the gram-negative bacterium Yersinia pestis routinely affects animals and occasionally humans, in the western United States. The strains native to the North American continent are thought to be derived from a single introduction in the late 19(th century. The degree to which these isolates have diverged genetically since their introduction is not clear, and new genomic markers to assay the diversity of North American plague are highly desired. To assay genetic diversity of plague isolates within confined geographic areas, draft genome sequences were generated by 454 pyrosequencing from nine environmental and clinical plague isolates. In silico assemblies of Variable Number Tandem Repeat (VNTR loci were compared to laboratory-generated profiles for seven markers. High-confidence SNPs and small Insertion/Deletions (Indels were compared to previously sequenced Y. pestis isolates. The resulting panel of mutations allowed clustering of the strains and tracing of the most likely evolutionary trajectory of the plague strains. The sequences also allowed the identification of new putative SNPs that differentiate the 2009 isolates from previously sequenced plague strains and from each other. In addition, new insertion points for the abundant insertion sequences (IS of Y. pestis are present that allow additional discrimination of strains; several of these new insertions potentially inactivate genes implicated in virulence. These sequences enable whole-genome phylogenetic analysis and allow the unbiased comparison of closely related isolates of a genetically monomorphic pathogen.

  3. Genome sequence of Babesia bovis and comparative analysis of apicomplexan hemoprotozoa.

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    Kelly A Brayton

    2007-10-01

    Full Text Available Babesia bovis is an apicomplexan tick-transmitted pathogen of cattle imposing a global risk and severe constraints to livestock health and economic development. The complete genome sequence was undertaken to facilitate vaccine antigen discovery, and to allow for comparative analysis with the related apicomplexan hemoprotozoa Theileria parva and Plasmodium falciparum. At 8.2 Mbp, the B. bovis genome is similar in size to that of Theileria spp. Structural features of the B. bovis and T. parva genomes are remarkably similar, and extensive synteny is present despite several chromosomal rearrangements. In contrast, B. bovis and P. falciparum, which have similar clinical and pathological features, have major differences in genome size, chromosome number, and gene complement. Chromosomal synteny with P. falciparum is limited to microregions. The B. bovis genome sequence has allowed wide scale analyses of the polymorphic variant erythrocyte surface antigen protein (ves1 gene family that, similar to the P. falciparum var genes, is postulated to play a role in cytoadhesion, sequestration, and immune evasion. The approximately 150 ves1 genes are found in clusters that are distributed throughout each chromosome, with an increased concentration adjacent to a physical gap on chromosome 1 that contains multiple ves1-like sequences. ves1 clusters are frequently linked to a novel family of variant genes termed smorfs that may themselves contribute to immune evasion, may play a role in variant erythrocyte surface antigen protein biology, or both. Initial expression analysis of ves1 and smorf genes indicates coincident transcription of multiple variants. B. bovis displays a limited metabolic potential, with numerous missing pathways, including two pathways previously described for the P. falciparum apicoplast. This reduced metabolic potential is reflected in the B. bovis apicoplast, which appears to have fewer nuclear genes targeted to it than other apicoplast

  4. Complete sequence and comparative analysis of the chloroplast genome of coconut palm (Cocos nucifera.

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    Ya-Yi Huang

    Full Text Available Coconut, a member of the palm family (Arecaceae, is one of the most economically important trees used by mankind. Despite its diverse morphology, coconut is recognized taxonomically as only a single species (Cocos nucifera L.. There are two major coconut varieties, tall and dwarf, the latter of which displays traits resulting from selection by humans. We report here the complete chloroplast (cp genome of a dwarf coconut plant, and describe the gene content and organization, inverted repeat fluctuations, repeated sequence structure, and occurrence of RNA editing. Phylogenetic relationships of monocots were inferred based on 47 chloroplast protein-coding genes. Potential nodes for events of gene duplication and pseudogenization related to inverted repeat fluctuation were mapped onto the tree using parsimony criteria. We compare our findings with those from other palm species for which complete cp genome sequences are available.

  5. Comparative genomic analysis of aspartic proteases in eight parasitic platyhelminths: insights into functions and evolution.

    Science.gov (United States)

    Wang, Shuai; Wei, Wei; Luo, Xuenong; Wang, Sen; Hu, Songnian; Cai, Xuepeng

    2015-03-15

    We performed genome-wide identifications and comparative genomic analyses of the predicted aspartic proteases (APs) from eight parasitic flatworms, focusing on their evolution, potentials as drug targets and expression patterns. The results revealed that: i) More members of family A01 were identified from the schistosomes than from the cestodes; some evidence implied gene loss events along the class Cestoda, which may be related to the different ways to ingest host nutrition; ii) members in family A22 were evolutionarily highly conserved among all the parasites; iii) one retroviral-like AP in family A28 shared a highly similar predicted 3D structure with the HIV protease, implying its potential to be inhibited by HIV inhibitor-like molecules; and iiii) retrotransposon-associated APs were extensively expanded among these parasites. These results implied that the evolutionary histories of some APs in these parasites might relate to adaptations to their parasitism and some APs might have potential serving as intervention targets.

  6. Complete sequence and comparative analysis of the chloroplast genome of coconut palm (Cocos nucifera).

    Science.gov (United States)

    Huang, Ya-Yi; Matzke, Antonius J M; Matzke, Marjori

    2013-01-01

    Coconut, a member of the palm family (Arecaceae), is one of the most economically important trees used by mankind. Despite its diverse morphology, coconut is recognized taxonomically as only a single species (Cocos nucifera L.). There are two major coconut varieties, tall and dwarf, the latter of which displays traits resulting from selection by humans. We report here the complete chloroplast (cp) genome of a dwarf coconut plant, and describe the gene content and organization, inverted repeat fluctuations, repeated sequence structure, and occurrence of RNA editing. Phylogenetic relationships of monocots were inferred based on 47 chloroplast protein-coding genes. Potential nodes for events of gene duplication and pseudogenization related to inverted repeat fluctuation were mapped onto the tree using parsimony criteria. We compare our findings with those from other palm species for which complete cp genome sequences are available.

  7. Comparative genomics of Streptomyces avermitilis, Streptomyces cattleya, Streptomyces maritimus and Kitasatospora aureofaciens using a Streptomyces coelicolor microarray system

    OpenAIRE

    2007-01-01

    DNA/DNA microarray hybridization was used to compare the genome content of Streptomyces avermitilis, Streptomyces cattleya, Streptomyces maritimus and Kitasatospora aureofaciens with that of Streptomyces coelicolor A3(2). The array data showed an about 93% agreement with the genome sequence data available for S. avermitilis and also showed a number of trends in the genome structure for Streptomyces and closely related Kitasatospora. A core central region was well conserved, which might be pre...

  8. Comparative genomics of Bordetella pertussis reveals progressive gene loss in Finnish strains.

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    Eriikka Heikkinen

    Full Text Available BACKGROUND: Bordetella pertussis is a gram-negative bacterium that infects the human respiratory tract and causes pertussis or whooping cough. The disease has resurged in many countries including Finland where the whole-cell pertussis vaccine has been used for more than 50 years. Antigenic divergence has been observed between vaccine strains and clinical isolates in Finland. To better understand genome evolution in B. pertussis circulating in the immunized population, we developed an oligonucleotide-based microarray for comparative genomic analysis of Finnish strains isolated during the period of 50 years. METHODOLOGY/PRINCIPAL FINDINGS: The microarray consisted of 3,582 oligonucleotides (70-mer and covered 94% of 3,816 ORFs of Tohama I, the strain of which the genome has been sequenced. Twenty isolates from 1953 to 2004 were studied together with two Finnish vaccine strains and two international reference strains. The isolates were selected according to their characteristics, e.g. the year and place of isolation and pulsed-field gel electrophoresis profiles. Genomic DNA of the tested strains, along with reference DNA of Tohama I strain, was labelled and hybridized. The absence of genes as established with microarrays, was confirmed by PCR. Compared with the Tohama I strain, Finnish isolates lost 7 (8.6 kb to 49 (55.3 kb genes, clustered in one to four distinct loci. The number of lost genes increased with time, and one third of lost genes had functions related to inorganic ion transport and metabolism, or energy production and conversion. All four loci of lost genes were flanked by the insertion sequence element IS481. CONCLUSION/SIGNIFICANCE: Our results showed that the progressive gene loss occurred in Finnish B. pertussis strains isolated during a period of 50 years and confirmed that B. pertussis is dynamic and is continuously evolving, suggesting that the bacterium may use gene loss as one strategy to adapt to highly immunized populations.

  9. A RAD-based linkage map and comparative genomics in the gudgeons (genus Gnathopogon, Cyprinidae

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    Kakioka Ryo

    2013-01-01

    Full Text Available Abstract Background The construction of linkage maps is a first step in exploring the genetic basis for adaptive phenotypic divergence in closely related species by quantitative trait locus (QTL analysis. Linkage maps are also useful for comparative genomics in non-model organisms. Advances in genomics technologies make it more feasible than ever to study the genetics of adaptation in natural populations. Restriction-site associated DNA (RAD sequencing in next-generation sequencers facilitates the development of many genetic markers and genotyping. We aimed to construct a linkage map of the gudgeons of the genus Gnathopogon (Cyprinidae for comparative genomics with the zebrafish Danio rerio (a member of the same family as gudgeons and for the future QTL analysis of the genetic architecture underlying adaptive phenotypic evolution of Gnathopogon. Results We constructed the first genetic linkage map of Gnathopogon using a 198 F2 interspecific cross between two closely related species in Japan: river-dwelling Gnathopogon elongatus and lake-dwelling Gnathopogon caerulescens. Based on 1,622 RAD-tag markers, a linkage map spanning 1,390.9 cM with 25 linkage groups and an average marker interval of 0.87 cM was constructed. We also identified a region involving female-specific transmission ratio distortion (TRD. Synteny and collinearity were extensively conserved between Gnathopogon and zebrafish. Conclusions The dense SNP-based linkage map presented here provides a basis for future QTL analysis. It will also be useful for transferring genomic information from a “traditional” model fish species, zebrafish, to screen candidate genes underlying ecologically important traits of the gudgeons.

  10. Comparative genome analysis between Agrostis stolonifera and members of the Pooideae subfamily, including Brachypodium distachyon.

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    Loreto Araneda

    Full Text Available Creeping bentgrass (Agrostis stolonifera, allotetraploid 2n = 4x = 28 is one of the major cool-season turfgrasses. It is widely used on golf courses due to its tolerance to low mowing and aggressive growth habit. In this study, we investigated genome re