scholarly journals Phylogenetic and Guanine-Cytosine Content Analysis of Symbiobacterium thermophilum Genes

2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Hiromi Nishida ◽  
Choong-Soo Yun
Keyword(s):  
Content Analysis ◽  
Gene Silencing ◽  
Early Stage ◽  
Gc Content ◽  
Dna Fragments ◽  
Bacterial Group ◽  
A Genome ◽  
Transposable Genetic Elements ◽  
Similar Gene ◽  
Gc Contents

Although the bacterium Symbiobacterium thermophilum has a genome with a high guanine-cytosine (GC) content (69%), it belongs to a low GC content bacterial group. We detected only 18 low GC content regions with 5 or more consecutive genes whose GC contents were below 65% in the genome of this organism. S. thermophilum has 66 transposase genes, which are markers of transposable genetic elements, and 38 (58%) of them were located in the low GC content regions, suggesting that Symbiobacterium has a similar gene silencing system as Salmonella. The top hit (best match) analyses for each Symbiobacterium protein showed that putative horizontally transferred genes and vertically inherited genes are scattered across the genome. Approximately 25% of the 3338 Symbiobacterium proteins have the highest similarity with the protein of a phylogenetically distant organism. The putative horizontally transferred genes also have a high GC content, suggesting that Symbiobacterium has gained many DNA fragments from phylogenetically distant organisms during the early stage of Firmicutes evolution. After acquiring genes, Symbiobacterium increased the GC content of the horizontally transferred genes and thereby maintained a genome with a high GC content.

Understanding the Technology Development Process at the Early Standardization Stage

2014 ◽  
Vol 12 (2) ◽  
pp. 1-20 ◽  
Author(s):  
Vladislav V. Fomin ◽  
Hanah Zoo ◽  
Heejin Lee
Keyword(s):  
Content Analysis ◽  
Software Defined Radio ◽  
Development Process ◽  
Technology Development ◽  
Weak Link ◽  
Early Stage ◽  
Radio Spectrum ◽  
Theoretical Frameworks ◽  
Development Framework ◽  
Practical Usefulness

This research is aimed at developing a document content analysis method to be applied in studies of standardization and technology development. The proposed method integrates two theoretical frameworks: the co-evolutionary technology development framework and the “D-N-S” (Design, Negotiation, Sense-making) framework for anticipatory standardizing. At the backdrop of complex and diversified landscape of science and R&D efforts in the technology domain, and the repeated criticism of the weak link between R&D initiatives and standardization, it is argued that the method offered in this work helps to better understand the internal dynamics of the technology development process at the early stage of standardization or pre-standardization, which, in turn, can help mobilize and direct the R&D initiatives. To demonstrate the practical usefulness of the proposed method, this paper conducts a content analysis of the research contributions presented in the COST Action IC0905 “Techno-Economic Regulatory Framework for Radio Spectrum Access for Cognitive Radio/ Software Defined Radio” (COST-TERRA).

Accessibility of Internet Based Electronic Resources: A Content Analysis of Public and Private University Library Websites in Bangladesh

2019 ◽  
Vol 9 (2) ◽  
pp. 28-33
Author(s):  
Shamima Yesmin .
Keyword(s):  
Content Analysis ◽  
Early Stage ◽  
Private University ◽  
Easy Access ◽  
University Libraries ◽  
Electronic Resources ◽  
Public And Private ◽  
University Library ◽  
Library Websites ◽  
The University

The purpose of this paper is to analyze the websites of university libraries to ascertain that libraries are effectively utilizing their respective websites to provide easy access to all electronic resources available in the library. The objective was also to a represent a comparative analysis between public and private university library websites regarding the presence of electronic resources with their easy access via the internet. For the purpose of this study, a research instrument in the form of comprehensive checklist of eighteen e-resources was developed to evaluate their accessibility in the websites of public and private university libraries. Twenty university library websites, comprised of ten top-ranked public and ten top-ranked private universities in Bangladesh, were studied for data collection using content analysis method. The findings demonstrate that the presence of e-resources on selected university library websites is still in its early stage, but it has been growing rapidly. The private university library websites are ahead of public university libraries in terms of the integration of web-resources. It is hoped that the findings of this paper will serve to assist the University librarians and other similar institutions in choosing, selecting and acquiring the most appropriate format of information resources, and making these available to their websites, which will both satisfy the needs of their library users and fit within their library budget.

scholarly journals An atypical class of non-coding small RNAs produced in rice leaves upon bacterial infection

2021 ◽  
Author(s):  
Ganna Reshetnyak ◽  
Jonathan M. Jacobs ◽  
Florence Auguy ◽  
Coline Sciallano ◽  
Lisa Claude ◽  
...  
Keyword(s):  
Gene Silencing ◽  
Stress Responses ◽  
Small Rnas ◽  
Early Stage ◽  
Kinase Domain ◽  
Transcriptional Gene Silencing ◽  
Small Interfering Rnas ◽  
Post Transcriptional Gene Silencing ◽  
Virulent Strains ◽  
Microbe Interactions

ABSTRACTNon-coding small RNAs (sRNA) act as mediators of gene silencing and regulate plant growth, development and stress responses. Early insights into plant sRNAs established a role in antiviral defense and they are now extensively studied across plant-microbe interactions. Here, sRNA sequencing discovered a class of sRNA in rice (Oryza sativa) specifically associated with foliar diseases caused by Xanthomonas oryzae bacteria. Xanthomonas-induced small RNAs (xisRNAs) loci were distinctively upregulated in response to diverse virulent strains at an early stage of infection producing a single duplex of 20-22nt sRNAs. xisRNAs production was dependent on the Type III secretion system, a major bacterial virulence factor for host colonization. xisRNA loci overlap with annotated transcripts sequences often encoding protein kinase domain proteins. A number of the corresponding rice cis-genes have documented functions in immune signaling and some xisRNA loci coincide with the coding sequence of a conserved kinase motif. xisRNAs exhibit features of small interfering RNAs and their biosynthesis depend on canonical components OsDCL1 and OsHEN1. xisRNA induction possibly mediates post-transcriptional gene silencing but they do not broadly suppress cis-genes expression on the basis of mRNA-seq data. Overall, our results identify a group of unusual sRNAs with a potential role in plant-microbe interactions.

scholarly journals Evolution of Nucleotide Composition in the SARS-CoV-2 Lineage: Implications for Vaccine Design

2020 ◽  
Author(s):  
Sankar Subramanian
Keyword(s):  
Base Composition ◽  
Scientific Community ◽  
Significant Positive Correlation ◽  
Gc Content ◽  
Nucleotide Composition ◽  
Reverse Direction ◽  
Novel Coronavirus ◽  
Near Future ◽  
Systematic Reduction ◽  
Gc Contents

The worldwide outbreak of a novel coronavirus, SARS-CoV-2 has caused a pandemic of respiratory disease. Due to this emergency, researchers around the globe have been investigating the evolution of the genome of SARS-CoV-2 in order to design vaccines. Here I examined the evolution of GC content of SARS-CoV-2 by comparing the genomes of the members of the group Betacoronavirus. The results of this investigation revealed a highly significant positive correlation between the GC contents of betacoronaviruses and their divergence from SARS-CoV-2. The betacoronaviruses that are distantly related to SARS-CoV-2 have much higher GC contents than the latter. Conversely, the closely related ones have low GC contents, which are only slightly higher than that of SARS-CoV-2. This suggests a systematic reduction in the GC content in the SARS-CoV-2 lineage over time. The declining trend in this lineage predicts a much-reduced GC content in the coronaviruses that will descend/evolve from SARS-CoV-2 in the future. Due to the three consecutive outbreaks (MERS-CoV, SARS-CoV and SARS-CoV-2) caused by the members of the SARS-CoV-2, the scientific community is emphasizing the need for universal vaccines that are effective across many strains including those, that will inevitably emerge in the near future. The reduction in GC contents implies an increase in the rate of GC→AT mutations than that the mutational changes in the reverse direction. Therefore, understanding the evolution of base composition and mutational patterns of SARS-CoV-2 could be useful in designing broad-spectrum vaccines that could identify and neutralize the present and future strains of this virus.

scholarly journals Characterization of the early response of Arabidopsis thaliana to Dickeya dadantii infection using expression profiling

2018 ◽  
Author(s):  
Frédérique Van Gijsegem ◽  
Frédérique Bitton ◽  
Anne-Laure Laborie ◽  
Yvan Kraepiel ◽  
Jacques Pédron
Keyword(s):  
Arabidopsis Thaliana ◽  
Early Stage ◽  
Plant Defence ◽  
Plant Responses ◽  
Type I ◽  
In Planta ◽  
Secretion Systems ◽  
Dickeya Dadantii ◽  
A Genome

AbstractTo draw a global view of plant responses to interactions with the phytopathogenic enterobacterale Dickeya dadantii, a causal agent of soft rot diseases on many plant species, we analysed the early Arabidopsis responses to D. dadantii infection. We performed a genome-wide analysis of the Arabidopsis thaliana transcriptome during D. dadantii infection and conducted a genetic study of identified responses.A limited set of genes related to plant defence or interactions with the environment were induced at an early stage of infection, with an over-representation of genes involved in both the metabolism of indole glucosinolates (IGs) and the jasmonate (JA) defence pathway. Bacterial type I and type II secretion systems are required to trigger the induction of IG and JA-related genes while the type III secretion system appears to partially inhibit these defence pathways. Using Arabidopsis mutants impaired in JA biosynthesis or perception, we showed that induction of some IG metabolism genes was COI1-dependent but, surprisingly, JA-independent. Moreover, characterisation of D. dadantii disease progression in Arabidopsis mutants impaired in JA or IG pathways showed that JA triggers an efficient plant defence response that does not involve IGs.The induction of the IG pathway by bacterial pathogens has been reported several times in vitro. This study shows for the first time, that this induction does indeed occur in planta, but also that this line of defence is ineffective against D. dadantii infection, in contrast to its role to counteract herbivorous or fungal pathogen attacks.

A Method for Content Analysis of (Pre-)Standardization Activities

2018 ◽  
pp. 116-137
Author(s):  
Vladislav V. Fomin ◽  
Hanah Zoo ◽  
Heejin Lee
Keyword(s):  
Content Analysis ◽  
Software Defined Radio ◽  
Technology Development ◽  
Weak Link ◽  
Early Stage ◽  
Radio Spectrum ◽  
Theoretical Frameworks ◽  
Content Analysis Method ◽  
Practical Usefulness ◽  
The Cost

This chapter is aimed at developing a document content analysis method to be applied in studies of standardization and technology development. The proposed method integrates two theoretical frameworks: the co-evolutionary technology development framework and the “D-N-S” (design, negotiation, sense-making) framework for anticipatory standardization. At the backdrop of the complex and diversified landscape of science and R&D efforts in the technology domain, and the repeated criticism of the weak link between R&D initiatives and standardization, the authors argue that the method offered in this chapter helps better understand the internal dynamics of the technology development process at the early stage of standardization or pre-standardization, which, in turn, can help mobilize and direct the R&D initiatives. To demonstrate the practical usefulness of the proposed method, they conduct a content analysis of the research contributions presented in the COST Action IC0905 “Techno-Economic Regulatory Framework for Radio Spectrum Access for Cognitive Radio/ Software Defined Radio” (COST-TERRA).

scholarly journals Draft Genome Sequence of Lactobacillus rhamnosus OSU-PECh-69, a Cheese Isolate with Antibacterial Activity

2020 ◽  
Vol 9 (37) ◽  
Author(s):  
Israel García-Cano ◽  
Walaa E. Hussein ◽  
Diana Rocha-Mendoza ◽  
Ahmed E. Yousef ◽  
Rafael Jiménez-Flores
Keyword(s):  
Genome Sequence ◽  
Antimicrobial Agents ◽  
Draft Genome ◽  
Lactobacillus Rhamnosus ◽  
Gc Content ◽  
Gene Clusters ◽  
Gram Negative Bacteria ◽  
The Novel ◽  
Content Type ◽  
A Genome

ABSTRACT The novel strain Lactobacillus rhamnosus OSU-PECh-69 was isolated from provolone cheese. It produces antimicrobial agents having a molecular mass of 5 to 10 kDa that are active against Gram-positive and Gram-negative bacteria. The strain has a genome sequence of 3,057,669 bp, a GC content of 46.6%, and up to two gene clusters encoding bacteriocins.

scholarly journals GPRED-GC: a Gene PREDiction model accounting for 5 ′- 3′ GC gradient

2019 ◽  
Vol 20 (S15) ◽  
Author(s):  
Prapaporn Techa-Angkoon ◽  
Kevin L. Childs ◽  
Yanni Sun
Keyword(s):  
Ab Initio ◽  
Gene Annotation ◽  
Gene Prediction ◽  
Source Code ◽  
Gc Content ◽  
Prediction Tools ◽  
Homologous Sequences ◽  
Manual Intervention ◽  
Grass Genomes ◽  
Gc Contents

Abstract Background Gene is a key step in genome annotation. Ab initio gene prediction enables gene annotation of new genomes regardless of availability of homologous sequences. There exist a number of ab initio gene prediction tools and they have been widely used for gene annotation for various species. However, existing tools are not optimized for identifying genes with highly variable GC content. In addition, some genes in grass genomes exhibit a sharp 5 ′- 3′ decreasing GC content gradient, which is not carefully modeled by available gene prediction tools. Thus, there is still room to improve the sensitivity and accuracy for predicting genes with GC gradients. Results In this work, we designed and implemented a new hidden Markov model (HMM)-based ab initio gene prediction tool, which is optimized for finding genes with highly variable GC contents, such as the genes with negative GC gradients in grass genomes. We tested the tool on three datasets from Arabidopsis thaliana and Oryza sativa. The results showed that our tool can identify genes missed by existing tools due to the highly variable GC contents. Conclusions GPRED-GC can effectively predict genes with highly variable GC contents without manual intervention. It provides a useful complementary tool to existing ones such as Augustus for more sensitive gene discovery. The source code is freely available at https://sourceforge.net/projects/gpred-gc/.

scholarly journals Efficient and accurate determination of genome-wide DNA methylation patterns in Arabidopsis thaliana with enzymatic methyl sequencing

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Suhua Feng ◽  
Zhenhui Zhong ◽  
Ming Wang ◽  
Steven E. Jacobsen
Keyword(s):  
Dna Methylation ◽  
Bisulfite Sequencing ◽  
Accurate Determination ◽  
Gc Content ◽  
Epigenetic Mark ◽  
Whole Genome ◽  
Whole Genome Bisulfite Sequencing ◽  
Genome Wide ◽  
A Genome ◽  
Genome Bisulfite Sequencing

Abstract Background 5′ methylation of cytosines in DNA molecules is an important epigenetic mark in eukaryotes. Bisulfite sequencing is the gold standard of DNA methylation detection, and whole-genome bisulfite sequencing (WGBS) has been widely used to detect methylation at single-nucleotide resolution on a genome-wide scale. However, sodium bisulfite is known to severely degrade DNA, which, in combination with biases introduced during PCR amplification, leads to unbalanced base representation in the final sequencing libraries. Enzymatic conversion of unmethylated cytosines to uracils can achieve the same end product for sequencing as does bisulfite treatment and does not affect the integrity of the DNA; enzymatic methylation sequencing may, thus, provide advantages over bisulfite sequencing. Results Using an enzymatic methyl-seq (EM-seq) technique to selectively deaminate unmethylated cytosines to uracils, we generated and sequenced libraries based on different amounts of Arabidopsis input DNA and different numbers of PCR cycles, and compared these data to results from traditional whole-genome bisulfite sequencing. We found that EM-seq libraries were more consistent between replicates and had higher mapping and lower duplication rates, lower background noise, higher average coverage, and higher coverage of total cytosines. Differential methylation region (DMR) analysis showed that WGBS tended to over-estimate methylation levels especially in CHG and CHH contexts, whereas EM-seq detected higher CG methylation levels in certain highly methylated areas. These phenomena can be mostly explained by a correlation of WGBS methylation estimation with GC content and methylated cytosine density. We used EM-seq to compare methylation between leaves and flowers, and found that CHG methylation level is greatly elevated in flowers, especially in pericentromeric regions. Conclusion We suggest that EM-seq is a more accurate and reliable approach than WGBS to detect methylation. Compared to WGBS, the results of EM-seq are less affected by differences in library preparation conditions or by the skewed base composition in the converted DNA. It may therefore be more desirable to use EM-seq in methylation studies.

scholarly journals Detection of Colorectal Cancer in Circulating Cell-Free DNA by Methylated CpG Tandem Amplification and Sequencing

2019 ◽  
Vol 65 (7) ◽  
pp. 916-926 ◽  
Author(s):  
Jingyi Li ◽  
Xin Zhou ◽  
Xiaomeng Liu ◽  
Jie Ren ◽  
Jilian Wang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Early Stage ◽  
Plasma Samples ◽  
Dna Hypermethylation ◽  
Cell Free Dna ◽  
Noncancerous Tissue ◽  
Clinical Sensitivity ◽  
Free Dna ◽  
A Genome ◽  
Circulating Cell Free Dna

Abstract BACKGROUND Aberrant DNA hypermethylation of CpG islands occurs frequently throughout the genome in human colorectal cancer (CRC). A genome-wide DNA hypermethylation analysis technique using circulating cell-free DNA (cfDNA) is attractive for the noninvasive early detection of CRC and discrimination between CRC and other cancer types. METHODS We applied the methylated CpG tandem amplification and sequencing (MCTA-Seq) method, with a fully methylated molecules algorithm, to plasma samples from patients with CRC (n = 147) and controls (n = 136), as well as cancer and adjacent noncancerous tissue samples (n = 66). We also comparatively analyzed plasma samples from patients with hepatocellular carcinoma (HCC; n = 36). RESULTS Dozens of DNA hypermethylation markers including known (e.g., SEPT9 and IKZF1) and novel (e.g., EMBP1, KCNQ5, CHST11, APBB1IP, and TJP2) genes were identified for effectively detecting CRC in cfDNA. A panel of 80 markers discriminated early-stage CRC patients and controls with a clinical sensitivity of 74% and clinical specificity of 90%. Patients with early-stage CRC and HCC could be discriminated at clinical sensitivities of approximately 70% by another panel of 128 markers. CONCLUSIONS MCTA-Seq is a promising method for the noninvasive detection of CRC.

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