keyword
MENU ▼
Read by QxMD icon Read
search

codon bias

keyword
https://www.readbyqxmd.com/read/28086981/does-antiretroviral-treatment-change-hiv-1-codon-usage-patterns-in-its-genes-a-preliminary-bioinformatics-study
#1
Navaneethan Palanisamy, Nathan Osman, Frédéric Ohnona, Hong-Tao Xu, Bluma Brenner, Thibault Mesplède, Mark A Wainberg
BACKGROUND: Codon usage bias has been described for various organisms and is thought to contribute to the regulation of numerous biological processes including viral infections. HIV-1 codon usage has been previously shown to be different from that of other viruses and man. It is evident that the antiretroviral drugs used to restrict HIV-1 replication also select for resistance variants. We wanted to test whether codon frequencies in HIV-1 sequences from treatment-experienced patients differ from those of treatment-naive individuals due to drug pressure affecting codon usage bias...
January 7, 2017: AIDS Research and Therapy
https://www.readbyqxmd.com/read/28077169/distinct-5-methylcytosine-profiles-in-poly-a-rna-from-mouse-embryonic-stem-cells-and-brain
#2
Thomas Amort, Dietmar Rieder, Alexandra Wille, Daria Khokhlova-Cubberley, Christian Riml, Lukas Trixl, Xi-Yu Jia, Ronald Micura, Alexandra Lusser
BACKGROUND: Recent work has identified and mapped a range of posttranscriptional modifications in mRNA, including methylation of the N6 and N1 positions in adenine, pseudouridylation, and methylation of carbon 5 in cytosine (m5C). However, knowledge about the prevalence and transcriptome-wide distribution of m5C is still extremely limited; thus, studies in different cell types, tissues, and organisms are needed to gain insight into possible functions of this modification and implications for other regulatory processes...
January 5, 2017: Genome Biology
https://www.readbyqxmd.com/read/28068395/correction-analysis-of-synonymous-codon-usage-bias-of-zika-virus-and-its-adaption-to-the-hosts
#3
Hongju Wang, Siqing Liu, Bo Zhang, Wenqiang Wei
[This corrects the article DOI: 10.1371/journal.pone.0166260.].
2017: PloS One
https://www.readbyqxmd.com/read/28062753/standard-codon-substitution-models-overestimate-purifying-selection-for-non-stationary-data
#4
Benjamin D Kaehler, Von Bing Yap, Gavin A Huttley
Estimation of natural selection on protein-coding sequences is a key comparative genomics approach for de novo prediction of lineage-specific adaptations. Selective pressure is measured on a per-gene basis by comparing the rate of non-synonymous substitutions to the rate of synonymous substitutions. All published codon substitution models have been time-reversible and thus assume that sequence composition does not change over time. We previously demonstrated that if time-reversible DNA substitution models are applied in the presence of changing sequence composition, the number of substitutions is systematically biased towards overestimation...
January 5, 2017: Genome Biology and Evolution
https://www.readbyqxmd.com/read/28045602/simplified-method-to-obtain-enhanced-expression-of-tau-protein-from-e-coli-and-one-step-purification-by-direct-boiling
#5
V Guru KrishnaKumar, Sharad Gupta
Tau is an intrinsically disordered protein responsible for maintaining the structure and stability of axonal microtubules. However, in certain disease conditions including Alzheimer's disease, tau protein may undergo biochemical and structural changes to form intracellular aggregates. Since tau is a proline and arginine rich eukaryotic protein, heterologous expression in E. coli often results in poor yield and has been a major technical challenge. In the current work, we have improved the expressed yield of tau by overcoming codon bias problem and established a simplified protocol for efficient extraction...
January 3, 2017: Preparative Biochemistry & Biotechnology
https://www.readbyqxmd.com/read/27992716/fidelity-of-the-dna-ligase-catalyzed-scaffolding-of-peptide-fragments-on-nucleic-acid-polymers
#6
Chun Guo, Ryan Hili
We describe the development and analysis of the T4 DNA ligase-catalyzed DNA templated polymerization of pentanucleotides modified with peptide fragments toward the generation of ssDNA-scaffolded peptides. A high-throughput duplex DNA sequencing method was developed to facilitate the determination of fidelity for various codon sets and library sizes used during the polymerization process. With this process, we identified several codon sets that enable the efficient and sequence-specific incorporation of peptide fragments along a ssDNA template at fidelities up to 99% and with low sequence bias...
December 28, 2016: Bioconjugate Chemistry
https://www.readbyqxmd.com/read/27964762/new-tools-to-analyze-overlapping-coding-regions
#7
Amir H Bayegan, Juan Antonio Garcia-Martin, Peter Clote
BACKGROUND: Retroviruses transcribe messenger RNA for the overlapping Gag and Gag-Pol polyproteins, by using a programmed -1 ribosomal frameshift which requires a slippery sequence and an immediate downstream stem-loop secondary structure, together called frameshift stimulating signal (FSS). It follows that the molecular evolution of this genomic region of HIV-1 is highly constrained, since the retroviral genome must contain a slippery sequence (sequence constraint), code appropriate peptides in reading frames 0 and 1 (coding requirements), and form a thermodynamically stable stem-loop secondary structure (structure requirement)...
December 13, 2016: BMC Bioinformatics
https://www.readbyqxmd.com/read/27935840/a-stress-induced-bias-in-the-reading-of-the-genetic-code-in-escherichia-coli
#8
Adi Oron-Gottesman, Martina Sauert, Isabella Moll, Hanna Engelberg-Kulka
: Escherichia coli mazEF is an extensively studied stress-induced toxin-antitoxin (TA) system. The toxin MazF is an endoribonuclease that cleaves RNAs at ACA sites. Thereby, under stress, the induced MazF generates a stress-induced translation machinery (STM), composed of MazF-processed mRNAs and selective ribosomes that specifically translate the processed mRNAs. Here, we further characterized the STM system, finding that MazF cleaves only ACA sites located in the open reading frames of processed mRNAs, while out-of-frame ACAs are resistant...
November 15, 2016: MBio
https://www.readbyqxmd.com/read/27919705/the-complete-mitochondrial-genome-of-thitarodes-sejilaensis-lepidoptera-hepialidae-a-host-insect-of-ophiocordyceps-sinensis-and-its-implication-in-taxonomic-revision-of-hepialus-adopted-in-china
#9
Zhiwen Zou, Qiang Min, Shiyu Cheng, Tianrong Xin, Bin Xia
The mitochondrial genome is widely used for phylogenetic analyses and evolutionary biology. The complete mitochondrial genome of Thitarodes sejilaensis (Lepidoptera: Hepialidae) was sequenced and analyzed in this study. This mitogenome is a typical circular molecule of 15,290bp, with the gene content, orientation and order identical to other insects in the family Hepialidae. The genome nucleotide composition is heavily biased towards As and Ts, accounting for 80.87% of total nucleotide content. The major strand shows a positive AT-skew and negative GC-skew...
February 15, 2017: Gene
https://www.readbyqxmd.com/read/27915291/the-landscape-of-microbial-phenotypic-traits-and-associated-genes
#10
Maria Brbić, Matija Piškorec, Vedrana Vidulin, Anita Kriško, Tomislav Šmuc, Fran Supek
Bacteria and Archaea display a variety of phenotypic traits and can adapt to diverse ecological niches. However, systematic annotation of prokaryotic phenotypes is lacking. We have therefore developed ProTraits, a resource containing ∼545 000 novel phenotype inferences, spanning 424 traits assigned to 3046 bacterial and archaeal species. These annotations were assigned by a computational pipeline that associates microbes with phenotypes by text-mining the scientific literature and the broader World Wide Web, while also being able to define novel concepts from unstructured text...
December 1, 2016: Nucleic Acids Research
https://www.readbyqxmd.com/read/27903241/abundant-rna-editing-sites-of-chloroplast-protein-coding-genes-in-ginkgo-biloba-and-an-evolutionary-pattern-analysis
#11
Peng He, Sheng Huang, Guanghui Xiao, Yuzhou Zhang, Jianing Yu
BACKGROUND: RNA editing is a posttranscriptional modification process that alters the RNA sequence so that it deviates from the genomic DNA sequence. RNA editing mainly occurs in chloroplasts and mitochondrial genomes, and the number of editing sites varies in terrestrial plants. Why and how RNA editing systems evolved remains a mystery. Ginkgo biloba is one of the oldest seed plants and has an important evolutionary position. Determining the patterns and distribution of RNA editing in the ancient plant provides insights into the evolutionary trend of RNA editing, and helping us to further understand their biological significance...
December 1, 2016: BMC Plant Biology
https://www.readbyqxmd.com/read/27897254/high-level-expression-of-improved-thermo-stable-alkaline-xylanase-variant-in-pichia-pastoris-through-codon-optimization-multiple-gene-insertion-and-high-density-fermentation
#12
Yihong Lu, Cheng Fang, Qinhong Wang, Yuling Zhou, Guimin Zhang, Yanhe Ma
In paper industry, xylanases are used to increase the pulp properties in bleaching process as its eco-friendly nature. The xylanases activity is hindered by high temperature and alkaline conditions with high enzyme production cost in the paper industry. Here, XynHB, an alkaline stable xylanase from Bacillus pumilus HBP8 was mutated at N188A to XynHBN188A. Expressed mutant in E. coli showed 1.5-fold higher xylanase activity than XynHB at 60 °C. The mutant expressed in Pichia pastoris was glycosylated, remained stable for 30 min at 60 °C...
November 29, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27893824/analysis-of-synonymous-codon-usage-bias-of-zika-virus-and-its-adaption-to-the-hosts
#13
Hongju Wang, Siqing Liu, Bo Zhang, Wenqiang Wei
Zika virus (ZIKV) is a mosquito-borne virus (arbovirus) in the family Flaviviridae, and the symptoms caused by ZIKV infection in humans include rash, fever, arthralgia, myalgia, asthenia and conjunctivitis. Codon usage bias analysis can reveal much about the molecular evolution and host adaption of ZIKV. To gain insight into the evolutionary characteristics of ZIKV, we performed a comprehensive analysis on the codon usage pattern in 46 ZIKV strains by calculating the effective number of codons (ENc), codon adaptation index (CAI), relative synonymous codon usage (RSCU), and other indicators...
2016: PloS One
https://www.readbyqxmd.com/read/27845207/codon-usage-pattern-and-prediction-of-gene-expression-level-in-bungarus-species
#14
Supriyo Chakraborty, Debojyoti Nag, Tarikul Huda Mazumder, Arif Uddin
Codon bias study in an organism gains significance in understanding the molecular mechanism as well as the functional conservation of gene expression during the course of evolution. The prime focus in this study is to compare the codon usage patterns among the four species belonging to the genus Bungarus (B. multicinctus, B. fasciatus, B. candidus and B. flaviceps) using several codon bias parameters. Our results suggested that relatively low codon bias exists in the coding sequences of the selected species...
March 10, 2017: Gene
https://www.readbyqxmd.com/read/27842572/dietary-nitrogen-alters-codon-bias-and-genome-composition-in-parasitic-microorganisms
#15
Emily A Seward, Steven Kelly
BACKGROUND: Genomes are composed of long strings of nucleotide monomers (A, C, G and T) that are either scavenged from the organism's environment or built from metabolic precursors. The biosynthesis of each nucleotide differs in atomic requirements with different nucleotides requiring different quantities of nitrogen atoms. However, the impact of the relative availability of dietary nitrogen on genome composition and codon bias is poorly understood. RESULTS: Here we show that differential nitrogen availability, due to differences in environment and dietary inputs, is a major determinant of genome nucleotide composition and synonymous codon use in both bacterial and eukaryotic microorganisms...
November 15, 2016: Genome Biology
https://www.readbyqxmd.com/read/27834374/trna-mediated-codon-biased-translation-in-mycobacterial-hypoxic-persistence
#16
Yok Hian Chionh, Megan McBee, I Ramesh Babu, Fabian Hia, Wenwei Lin, Wei Zhao, Jianshu Cao, Agnieszka Dziergowska, Andrzej Malkiewicz, Thomas J Begley, Sylvie Alonso, Peter C Dedon
Microbial pathogens adapt to the stress of infection by regulating transcription, translation and protein modification. We report that changes in gene expression in hypoxia-induced non-replicating persistence in mycobacteria-which models tuberculous granulomas-are partly determined by a mechanism of tRNA reprogramming and codon-biased translation. Mycobacterium bovis BCG responded to each stage of hypoxia and aerobic resuscitation by uniquely reprogramming 40 modified ribonucleosides in tRNA, which correlate with selective translation of mRNAs from families of codon-biased persistence genes...
November 11, 2016: Nature Communications
https://www.readbyqxmd.com/read/27830053/unbiased-mitoproteome-analyses-confirm-non-canonical-rna-expanded-codon-translations
#17
Hervé Seligmann
Proteomic MS/MS mass spectrometry detections are usually biased towards peptides cleaved by experimentally added digestion enzyme(s). Hence peptides resulting from spontaneous degradation and natural proteolysis usually remain undetected. Previous analyses of tryptic human proteome data (cleavage after K, R) detected non-canonical tryptic peptides translated according to tetra- and pentacodons (codons expanded by silent mono- and dinucleotides), and from transcripts systematically (a) deleting mono-, dinucleotides after trinucleotides (delRNAs), (b) exchanging nucleotides according to 23 bijective transformations...
2016: Computational and Structural Biotechnology Journal
https://www.readbyqxmd.com/read/27822527/differential-functional-constraints-cause-strain-level-endemism-in-polynucleobacter-populations
#18
Naseer Sangwan, Iratxe Zarraonaindia, Jarrad T Hampton-Marcell, Herbert Ssegane, Tifani W Eshoo, Geeta Rijal, M Cristina Negri, Jack A Gilbert
The adaptation of bacterial lineages to local environmental conditions creates the potential for broader genotypic diversity within a species, which can enable a species to dominate across ecological gradients because of niche flexibility. The genus Polynucleobacter maintains both free-living and symbiotic ecotypes and maintains an apparently ubiquitous distribution in freshwater ecosystems. Subspecies-level resolution supplemented with metagenome-derived genotype analysis revealed that differential functional constraints, not geographic distance, produce and maintain strain-level genetic conservation in Polynucleobacter populations across three geographically proximal riverine environments...
May 2016: MSystems
https://www.readbyqxmd.com/read/27816910/progressive-and-biased-divergent-evolution-underpins-the-origin-and-diversification-of-peridinin-dinoflagellate-plastids
#19
Richard G Dorrell, Christen M Klinger, Robert J Newby, Erin R Butterfield, Elisabeth Richardson, Joel B Dacks, Christopher J Howe, Ellen R Nisbet, Chris Bowler
Dinoflagellates are algae of tremendous importance to ecosystems and to public health. The cell biology and genome organization of dinoflagellate species is highly unusual. For example, the plastid genomes of peridinin-containing dinoflagellates encode only a minimal number of genes arranged on small elements termed "minicircles". Previous studies of peridinin plastid genes have found evidence for divergent sequence evolution, including extensive substitutions, novel insertions and deletions, and use of alternative translation initiation codons...
November 4, 2016: Molecular Biology and Evolution
https://www.readbyqxmd.com/read/27808241/analysis-of-codon-usage-patterns-in-ginkgo-biloba-reveals-codon-usage-tendency-from-a-u-ending-to-g-c-ending
#20
Bing He, Hui Dong, Cong Jiang, Fuliang Cao, Shentong Tao, Li-An Xu
As one of the most ancient tree species, the codon usage pattern analysis of Ginkgo biloba is a useful way to understand its evolutionary and genetic mechanisms. Several studies have been conducted on angiosperms, but seldom on gymnosperms. Based on RNA-Seq data of the G. biloba transcriptome, amount to 17,579 unigenes longer than 300 bp were selected and analyzed from 68,547 candidates. The codon usage pattern tended towards more frequently use of A/U-ending codons, which showed an obvious gradient progressing from gymnosperms to dicots to monocots...
November 3, 2016: Scientific Reports
keyword
keyword
52406
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"