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To assess, if the SARS-CoV-2 mutate in a similar pattern globally or has a specific pattern in any given population. We report, the insertion of TTT at 11085, which adds an extra amino acid, F to the NSP6 at amino acid position 38. The highest occurrence of TTT insertion at 11,085 position was found in UK derived samples (65.97%). The second and third highest occurrence of the mutation were found in Australia (8.3%) and USA (4.16%) derived samples, respectively. Another important discovery of this study is the C27945T mutation, which translates into the termination of ORF-8 after 17 amino acids, reveals that the SARS-CoV-2 can replicate without the intact ORF-8 protein. We found that the 97% of C27945T mutation of global occurrence, occurred in Europe and the USA derived samples. Two of the reported mutations (11085TTT insertion and C27945T nonsense), which seemed to reduce Type I interferon response are linked to specific geographical locations of the host and implicate region-specific mutations in the virus. The findings of this study signify that SARS-CoV-2 has the potential to adapt differently to different populations. [ABSTRACT FROM AUTHOR]

Ten dsRNA segments were extracted from Sclerotium hydrophilum isolate (HZ11). The isolation of virus-like particles contained 10 dsRNA segments with the same number and migration as those extracted directly from the fungal mycelia. Two of these dsRNA segments, dsRNA2 and dsRNA7, were cloned and sequenced. They were 2121 and 1953 bp, respectively. The dsRNA2 encodes a RNA-dependent RNA polymerase. The dsRNA7 contains two open reading frames that encode putative proteins of unknown functions. Phylogenetic analysis of the putative proteins indicated that they are closely related to protein encoded by unclassified viruses, such as Cryphonectria parasitica bipartite mycovirus 1, Lactarius rufus RNA virus 1, Penicillium aurantiogriseum bipartite virus 1, and Curvularia thermal tolerance virus. The 5′- and 3′-untranslated regions of the two dsRNAs share significant sequence identity and contain conserved sequence stretches. It suggested that dsRNA2 and dsRNA7 have a common origin and a close phylogenetic relationship to a group of unclassified viruses. [ABSTRACT FROM AUTHOR]

The study of the dependence of the mutation frequency in human genome was conducted by the example of a set of documented single nucleotide polymorphisms (SNPs) from the 1000 genomes project. The tasks of the development of new computer methods for the statistical analysis of genetic texts based on estimations of sequences complexity were considered. The application of the complexity profiles in a sliding window to the analysis of sites containing single nucleotide polymorphisms in the human genome was demonstrated. A local decrease in the text complexity near SNPs was established. Based on the analysis of the complexity profiles in the regions containing SNPs, it was demonstrated that the flanking monomer repeats determine the decreased context complexity of single nucleotide polymorphism sites in human genome. The effect of local decrease in the text complexity level for sequences flanking SNP sites was confirmed for the data on polymorphisms in the rat and mouse genomes. Differences in the context organization for coding and regulatory sequences (that are reflected in the text complexity of nucleotide sequences containing SNPs) were determined. Changes in the point mutation frequencies were previously demonstrated for the sequences containing microsatellites. Using more general mathematical apparatus and more complete data, a saturation of local genomic surroundings containing SNPs with polytracts and simple repeated sequences was demonstrated in this work. Oligonucleotides with increased frequency in the genomic SNP surroundings in human were determined; their association with polytracts was demonstrated. The presence of polytracts can indicate a greater probability of a break in the double DNA strand at this point (resulting in an increased frequency of nucleotide substitutions). The obtained estimations were determined by a previously developed complex of computer programs, which allows us to efficiently determine the frequency spectrum of oligonucleotides with a fixed length, to compare nucleotide frequencies in a larger sample (in addition to estimating the complexity of the phased sequences). [ABSTRACT FROM AUTHOR]

Foot-and-mouth disease (FMD) outbreaks recently affected 2 countries (Japan and South Korea) in eastern Asia that were free of FMD without vaccination. Analysis of viral protein 1 nucleotide sequences indicated that FMD serotype A and O viruses that caused these outbreaks originated in mainland Southeast Asia to which these viruses are endemic.

From February through May of 1999, 13 cases of Influenza A virus (FLUAV), type H1N1 were reported at a Department of Defense influenza surveillance sentinel site in Lima, Peru. Genetic and antigenic analysis by hemagglutination inhibition and direct nucleotide sequencing of the HA1 region of the hemagglutinin gene were performed on two isolates, A/Peru/1641/99 and A/Peru/1798/99. Both isolates were distinct from the Bayern/7/95-like viruses circulating in the Americas and closely related to a Beijing/262/95-like variant, A/New Caledonia/20/99. With the exception of travel-related cases, the detection of these isolates represents the first appearance of New Caledonia/20/99-like viruses in the Americas. Since the characterization of these Peru isolates, a number of New Caledonia/20/99-like viruses have been reported worldwide. For the 2000/01 and 2001/02 influenza seasons, the World Health Organization (WHO) has recommended the inclusion of A/New Caledonia/20/99 as the H1N1 vaccine component for both the southern and northern hemispheres.

Results of computational analysis and visualization of differences in gene structures using polarization coding are presented. A two-dimensional phase screen, where each element of which corresponds to a specific basic nucleotide (adenine, cytosine, guanine, or thymine), displays the analyzed nucleotide sequence. Readout of the screen with a coherent beam characterized by a given polarization state forms a diffracted light field with a local polarization structure that is unique for the analyzed nucleotide sequence. This unique structure is described by spatial distributions of local values of the Stokes vector components. Analysis of these distributions allows the comparison of nucleotide sequences for different strains of pathogenic microorganisms and frequency analysis of the sequences. The possibilities of this polarization-based technique are illustrated by the model data obtained from a comparative analysis of the spike protein gene sequences for three different model variants (Wuhan, Delta, and Omicron) of the SARS-CoV-2 virus. Various modifications of polarization encoding and analysis of gene structures and a possibility for instrumental implementation of the proposed method are discussed.

Optimal string alignment is used to discover evolutionary relationships or mutations in DNA/RNA or protein sequences. Errors, missing parts or uncertainty in such a sequence can be covered with wild cards, so-called wild bases. This makes an alignment possible even when the data are corrupted or incomplete. The extended pairwise local alignment of wild card DNA/RNA sequences requires additional calculations in the dynamic programming algorithm and necessitates a subsequent best- and worst-case analysis for the wild card positions. In this paper, we propose an algorithm which solves the problem of input data wild cards, offers a highly flexible set of parameters and displays a detailed alignment output and a compact representation of the mutated positions of the alignment. An implementation of the algorithm can be obtained at https://github.com/sysbio-bioinf/swat+ and http://sysbio.uni-ulm.de/?Software:Swat+. [ABSTRACT FROM AUTHOR]

The purpose of study was to compare acetyl-CoA synthetases (ASC1, ACS2) in yeast: Ashbya gossipii, Candida albicans, Candida glabrata, Debaromyces hansenii, Kluyveromyces lactis, Saccharomyces cerevisiae, Zygosaccharomyces bailii and ACSA in Schizosaccharomyces pombe. The first step was to compare nucleotide sequence of genes and aminoacid sequence of enzymes. For nucleotide sequences two different clusters of genes were obtained (ACS1 and ACS2) located between them ACSA gene from S. pombe. For aminoacid sequences obtained results were similar to nucleotide ones. In the next step, comparison of amino acid sequences to the sequence of ACS2 from Z. bailii, three conservative fragments were detected. Moreover the presence of motif III (consider as catalytically important) was confirmed. Five sequences were found (FTAGD, YFTGD, YFAGD, LRTGD, YFSGD) and their exact positions were determined. [ABSTRACT FROM AUTHOR]

Specific primers play an important role in polymerase chain reaction (PCR) experiments, and therefore it is essential to find specific primers of outstanding quality. Unfortunately, many PCR constraints must be simultaneously inspected which makes specific primer selection difficult and time‐consuming. This paper introduces a novel computational intelligence‐based method, Teaching‐Learning‐Based Optimisation, to select the specific and feasible primers. The specified PCR product lengths of 150–300 bp and 500–800 bp with three melting temperature formulae of Wallace's formula, Bolton and McCarthy's formula and SantaLucia's formula were performed. The authors calculate optimal frequency to estimate the quality of primer selection based on a total of 500 runs for 50 random nucleotide sequences of 'Homo species' retrieved from the National Center for Biotechnology Information. The method was then fairly compared with the genetic algorithm (GA) and memetic algorithm (MA) for primer selection in the literature. The results show that the method easily found suitable primers corresponding with the setting primer constraints and had preferable performance than the GA and the MA. Furthermore, the method was also compared with the common method Primer3 according to their method type, primers presentation, parameters setting, speed and memory usage. In conclusion, it is an interesting primer selection method and a valuable tool for automatic high‐throughput analysis. In the future, the usage of the primers in the wet lab needs to be validated carefully to increase the reliability of the method. [ABSTRACT FROM AUTHOR]

It is known that nucleotide sequences are not totally homogeneous and this heterogeneity could not be due to random fluctuations only. Such heterogeneity poses a problem of making sequence segmentation into a set of homogeneous parts divided by the points called “change points”. In this work we investigated a special case of change points-paired change points (PCP). We used a well-known property of coding sequences-triplet periodicity (TP). The sequences that we are especially interested in consist of three successive parts: the first and the last parts have similar TP while the middle part has different TP type. We aimed to find the genes with PCP and provide explanation for this phenomenon. We developed a mathematical method for the PCP detection based on the new measure of similarity between TP matrices. We investigated 66,936 bacterial genes from 17 bacterial genomes and revealed 2,700 genes with PCP and 6,459 genes with single change point (SCP). We developed a mathematical approach to visualize the PCP cases. We suppose that PCP could be associated with double fusion or insertion events. The results of investigating the sequences with artificial insertions/fusions and distribution of TP inside the genome support the idea that the real number of genes formed by insertion/ fusion events could be 5-7 times greater than the number of genes revealed in the present work. [ABSTRACT FROM PUBLISHER]

We consider a DNA strand as a mathematical statement. Inspired by the work of Kurt Gödel, we attach to each DNA strand a Gödel's number, a product of prime numbers raised to appropriate powers. To each DNA chain corresponds a single Gödel's number G , and inversely given a Gödel's number G , we can specify the DNA chain it stands for. Next, considering a single DNA strand composed of N bases, we study the statistical distribution of g , the logarithm of G. Our assumption is that the choice of the m th term is random and with equal probability for the four possible outcomes. The 'experiment', to some extent, is similar to throwing N times a four-faces die. Through the moment generating function we obtain the discrete and then the continuum distribution of g. There is an excellent agreement between our formalism and simulated data. At the end we compare our formalism to actual data, to specify the presence of non-random fluctuations. [ABSTRACT FROM AUTHOR]

Isolates of the fungus Beauveria bassiana have different levels of virulence and repellency against the termite Macrotermes michaelseni. In the present study, we compared the volatile profiles and gene sequences of two isolates of the fungus with different levels of virulence and repellence to the termite. Gas chromatography-mass spectrometric analyses showed quantitative and qualitative differences in the composition of volatiles of the two isolates. The repellencies of synthetic blends of 10 prominent components that mimicked the volatiles of each of the two isolates were significantly different. Subtractive bioassays showed that the repellency of each isolate was due to synergistic effects of a few constituents. As previously reported for isolates of Metarhizium anisopliae, some differences also were found in the nucleotide sequences of the two isolates of B. bassiana, suggesting a genetic basis for the observed intra-specific differences in their repellency and virulence against the termite. [ABSTRACT FROM AUTHOR]

Priotyrannus closteroides Thomson, 1877 (Coleoptera: Cerambycidae) is the trunk borer of orange trees. In this study, we sequenced and annotated the whole mitochondrial genome of P. closteroides . The results showed that the length of the complete mitochondrial genome is 15,854 bp with an overall GC content of 32.11%. The genome encodes 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), and two ribosomal RNA genes (rRNAs). The relevant phylogenetic tree distinctly showed that P. closteroides is clustered with Dorysthenes paradoxus and Dorysthenes granulosus . This study provides a piece of valuable genomic information for the population genetics, evolution, and classification of P. closteroides ., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

The aim of the present study is to compare the biological and molecular properties of Ukrainian soybean mosaic virus (SMV) isolates with those of known strains or isolates from other countries, and to trace their possible origin. The methods of mechanical inoculation, reverse transcription polymerase chain reaction, DNA sequencing and phylogenetic analysis have been used. Results. Five SMV isolates have been collected and biologically purified from breeding plots in Vinnitsa region of Ukraine. It has been found that all these isolates show the same reaction patterns when infecting 11 differential soybean cultivars. Phylogenetic analysis of sequences of the coat protein coding region and P1 coding region revealed strong genetic relationships between representative Ukrainian (UA1Gr) and SMV-VA2 isolates which together were sorted in one clade with G2 strain. The investigation of sequence identity showed that different genomic regions of SMV were under different evolutionary constraints. Conclusions. SMV, isolated in Ukraine for the first time, belongs to the G2 strain group that is widespread in North America. The SMV isolates obtained in this work may be employed in the Ukrainian national breeding programs to create soybean with durable virus resistance. [ABSTRACT FROM AUTHOR]

A molecular epidemiological study of novel strain of Rubella virus isolated during the outbreak in Western Siberia in 2004 is described. A detailed phylogenetic analysis performed based upon entire SP-section, which encodes all three Rubella structural proteins (C, E2, and El), is implemented. This analysis provides characterization of this strain and classifies it in the 1H genotype, thereby correcting a previous classification of this strain based upon a shorter nucleotide sequence only encoding El protein. Therefore, this study identified the genotype of the Rubella virus not previously detected in western Siberia (and even the entire Russian Federation), which highlights the importance of more extensive characterization of genetic variability of the Rubella virus, especially with regard to the potential influence of vaccination on the Rubella virus mutagenesis. [ABSTRACT FROM AUTHOR]

This paper describes the principal molecular markers used to identify B. bovis and B. bigemina reported in the scientific literature. A systematic review was designed based on the application of the PICO methodologic modified strategy to define the nucleotide sequences detected in different geographical locations and their diagnostic utility. An advanced search was made in data bases ScienceDirect, SpringerLink and PubMed. Using the terms "Babesia bovis" and "DNA" and "Babesia bigemina" and "DNA". A total of 68 original articles were selected after the information was filtered. Both included and excluded articles were registered in tables, where its position of their status, within the study, was represented. The 68 articles were evaluated using a previously defined criteria of inclusion or exclusion. A total of 21 articles met the inclusion criteria and were included in this study. It was described the usefulness of molecular markers referenced in the scientific literature from 1995 to 2010: small-subunit ribosomal rna, cytochrome b gene, msa-1 and msa-2c gene, bv gene, elongation factor-1 alpha (ef-1α), beta-tubulin gene, sbp 1-2-3, and rap genes, its diagnostic application and its use in different geographical locations. Molecular markers used for detection of bovine babesia vary by geographic region, degree of genetic conservation and results of previous studies that conclude their diagnostic utility. [ABSTRACT FROM AUTHOR]

DNA sequence data have been widely used to evaluate species delimitations and examine infraspecific relationships. However, species placements inferred from different nucleotide sequences are frequently in conflict. As an example of plant species placement based on nucleotide sequences, the phylogenetic placement of Dipteronia dyerana Henry (Aceraceae) was analyzed in the present study. The study species included eight Acer species (from different sections of Acer), two Dipteronia species, and two outgroup taxa. Phylogenetic trees based on five datasets (ITS, trnL-F, trnD-trnT, psbM-trnD, and rpl16 regions) as well as their combined datasets were generated by using maximum parsimony (MP) and maximum likelihood (ML) analyses. Further analyses were conducted to compare the strict consensus trees based on single regions and the combination of different regions. The results revealed a significant discrepancy among the phylogenetic placements of D. dyerana, inferred from various sequences. Phylogenetic trees using MP analysis based on trnD-trnT, rpl16, and the four chloroplast combined sequences supported the genus Dipteronia as a monophyletic group, while in the other trees D. dyerana was positioned either in parallel with D. sinensis and Acer species or within the genus Acer. In ML analysis, only rpl16 and the four chloroplast combined sequence datasets supported the genus Dipteronia as a monophyletic group. We concluded that, although significant genetic differentiation occurred between D. dyerana and D. sinensis, D. dyerana was more advanced than D. sinensis. However, whether Dipteronia is monophyletic remains to be further investigated, e.g., by using more closely related taxa and more sequences. Furthermore, in addition to internal transcribed spacer sequences, more chloroplast gene sequences should be used for phylogenetic analyses of species. [ABSTRACT FROM AUTHOR]

Crassulaceae (orpine or stonecrop family) is the most species-rich (ca. 1400 spp) family in the order Saxifragales. Most members of the family are succulent plants. Phenotypic diversity and large number of species complicates systematics of the family and obscures reconstruction of relationship within it. Phylogenetic analyzes based on morphological and molecular markers placed Crassulaceae as one of the crown clades of Saxifragales. In this contribution a review of phylogenetic studies on the family Crassulaceae, based on DNA nucleotide sequence comparisons is presented; major clades established in the family are characterised; their structure and polyphylesis of some genera are discussed. It is shown that the traditional taxonomic structure of Crassulaceae contradicts pattern of phylogenetic relationships between its members. We critically analyzed recent taxonomic systems of the family and stress that homoplasy of morphological characters does not allow to use them to reconstruct relationships between crassulacean taxa even at the low taxonomic levels. [ABSTRACT FROM AUTHOR]

Abstract: Legionella pneumophila serogroup 1 is the most common etiological agent of legionellosis. We have used clinical and environmental isolates from different sources to compare their genetic variability. We have obtained the nucleotide sequence for six protein-coding loci, included in the SBT scheme for L. pneumophila, and three intergenic regions from 127 samples, 47 of environmental origin and 80 from clinical samples. Levels of genetic variability were found to be higher in the environmental than in the clinical samples, but these did not represent a mere subset of the former. Not a single case of full identity between clinical and environmental isolates was found, which raises the possibility that only a specific subset of environmental isolates is actually capable of producing infection in humans. A phylogenetic analysis of the concatenate alignment of the nine loci sequences showed four main groups, each including clinical and environmental isolates, although their distribution was not uniform among them. The comparison of each individual gene tree with the others revealed several cases of incongruence involving samples from both origins, thus suggesting the presence of recombination in the two groups. [Copyright &y& Elsevier]

The adaptation of Mycoplasma gallisepticum S6 to adverse environmental conditions is associated with the transformation of vegetative cell forms to viable but nonculturable (VBNC) forms. The vegetative and VBNC forms proved to differ in the spectrum of PCR products amplified from pvpA-gene, which codes for the phase-variable cytoadhesion protein. The vegetative forms displayed only one amplicon, which contained one open reading frame (1086 bp) with a high homology (97%) to pvpA-gene of M. gallisepticum R and Pendik. The VBNC forms of M. gallisepticum S6 had additional amplicons, whose open reading frames were absent from the complete database sequence of the mycoplasma genome. A high nucleotide sequence homology (54–55%) between pvpA-gene and the additional pvpA-gene amplicons made it possible to suggest that pvpA-gene provided a source for the formation of new regions within the mycoplasma genome during adaptation to adverse environmental conditions. [ABSTRACT FROM AUTHOR]

Strain BBS, the purple sulfur bacterium assigned initially to the species Thiocapsa roseopersicina, is the best studied representative of this species. However, no molecular phylogenetic analysis has been performed to confirm its systematic position. Based on the results of analysis of the sequences of 16S rRNA, cbbL, and nifH genes, DNA-DNA hybridization with the T. roseopersicina type strain, and comparative analysis of the phenotypic characteristics of various species belonging to the genus Thiocapsa, we suggest that strain BBS should be assigned to a new species of the genus Thiocapsa, Thiocapsa bogorovii sp. nov. [ABSTRACT FROM AUTHOR]

In previous work, we presented GAMI [1], an approach to motif inference that uses a genetic algorithms search. GAMI is designed specifically to find putative conserved regulatory motifs in noncoding regions of divergent species and is designed to allow for analysis of long nucleotide sequences. In this work, we compare GAMI's performance when run with its original fitness function (a simple count of the number of matches) and when run with information content (IC), as well as several variations on these metrics. Results indicate that IC does not identify highly conserved regions and, thus, is not the appropriate metric for this task, whereas variations on IC, as well as the original metric, succeed in identifying putative conserved regions. [ABSTRACT FROM PUBLISHER]

Abstract: Background: Herpes simplex virus (HSV) is assumed to cause recrudescent lesions, usually through endogenous recurrence and rarely through exogenous re-infection. The occurrence of exogenous re-infection in genital and corneal HSV infections has been previously demonstrated using genomic analysis, while exogenous re-infection in oral-facial HSV infections has not been shown. Objectives: To confirm the occurrence of exogenous HSV re-infection in oral-facial HSV infections. Study design: Seven isolates (isolates 1–7) of herpes simplex virus type 1 (HSV-1) were sequentially separated from the same individual. Genomic profiles of HSV-1 isolates were studied: (i) by analysis of 20 RFLPs (restriction fragment length polymorphisms) and (ii) by the determination of nucleotide sequences of a PCR-amplified DNA fragment encompassing reiteration VII (hypervariable region) that belongs to sequences containing short tandem repeats. Results: Isolates 1–5 were the same (F83 genotype) and isolates 6 and 7 were the same (F84 genotype), although isolates 1–5 were markedly different from isolates 6 and 7 in genomic profiles. Conclusions: The infection associated with isolates 6 and 7 was due to exogenous re-infection with F84 genotype virus, thus indicating the occurrence of exogenous HSV re-infection in oral-facial HSV infections. [Copyright &y& Elsevier]

Maximum-likelihood models of codon and amino acid substitution were used to analyze the lung-specific surfactant protein C (SP-C) from terrestrial, semi-aquatic, and diving mammals to identify lineages and amino acid sites under positive selection. Site models used the nonsynonymous/synonymous rate ratio (ω) as an indicator of selection pressure. Mechanistic models used physicochemical distances between amino acid substitutions to specify nonsynonymous substitution rates. Site models strongly identified positive selection at different sites in the polar N-terminal extramembrane domain of SP-C in the three diving lineages: site 2 in the cetaceans (whales and dolphins), sites 7, 9, and 10 in the pinnipeds (seals and sea lions), and sites 2, 9, and 10 in the sirenians (dugongs and manatees). The only semi-aquatic contrast to indicate positive selection at site 10 was that including the polar bear, which had the largest body mass of the semi-aquatic species. Analysis of the biophysical properties that were influential in determining the amino acid substitutions showed that isoelectric point, chemical composition of the side chain, polarity, and hydrophobicity were the crucial determinants. Amino acid substitutions at these sites may lead to stronger binding of the N-terminal domain to the surfactant phospholipid film and to increased adsorption of the protein to the air-liquid interface. Both properties are advantageous for the repeated collapse and reinflation of the lung upon diving and resurfacing and may reflect adaptations to the high hydrostatic pressures experienced during diving. [ABSTRACT FROM AUTHOR]

This paper introduces an algorithm for the lossless compression of DNA files which contain annotation text besides the nucleotide sequence. First, a grammar is specifically designed to capture the regularities of the annotation text. A revertible transformation uses the grammar rules in order to equivalently represent the original file as a collection of parsed segments and a sequence of decisions made by the grammar parser. This decomposition enables the efficient use of state-of-the-art encoders for processing the parsed segments. The output size of the decision-making process of the grammar is optimized by extending the states to account for high-order Markovian dependencies. The practical implementation of the algorithm achieves a significant improvement when compared to the general-purpose methods currently used for DNA files. [ABSTRACT FROM PUBLISHER]

Perkinsus olseni infections are reported at 10%–84% prevalences among Austrovenus stutchburyi clams (cockles) in northern New Zealand coastal waters. However, P. olseni has not yet been propagated in vitro from New Zealand clams. In our sample of A. stutchburyi clams from Mangemangaroa Stream, New Zealand, 24% (8/34) showed low-intensity Perkinsus sp. infections among mantle and gill tissues incubated in alternative Ray's fluid thioglycollate medium (ARFTM), and 5% (4/79) showed Perkinsus sp. lesions by histological analyses. Among clams that were screened using a polymerase chain reaction (PCR) assay, 16% (3/19) were positive for Perkinsus sp. DNA. Alternative Ray's fluid thioglycollate medium-enlarged hypnospores from tissues of five infected clams yielded three in vitro Perkinsus sp. isolate cultures that were cloned before sequencing internal transcribed spacer (ITS) regions of their rRNA gene complex. For one isolate, ATCC PRA-205, large subunit (LSU) rRNA and actin genes were also sequenced. All nucleotide sequences from all isolates consistently identified them as P. olseni, as did their in vitro cell cycles and zoosporulation characteristics. All in vitro isolate cultures and their respective monoclonal derivative strains were cryopreserved and deposited for archiving and distribution by the American Type Culture Collection ( ). [ABSTRACT FROM AUTHOR]

Abstract: In this study, a set of 80 completely sequenced procaryotic genomes has been analysed by an alignment-free method, namely the expectancy-rectified frequency of bigrams or 2-tuples, representing the 16 combinations of A, T, G, C. It demonstrates that all genomes exhibit periodic oscillations of their nucleotide sequence, with a period close to 11 phosphodiester bonds, and resembling in shape an exponentially dampened sinusoid at the distance from 5 to 49 bonds. Interestingly, the amplitude of nucleotide oscillation (but not the period) can differ drastically from one species to another. I show that these differences are due neither to the (G + C) content, nor to the size of the genome. They are not directly related to phylogeny, since specific genomes from Archaea and Bacteria can display large as well as small amplitudes. I have compared also a set of genes coding for proteins rich in alpha helical structures (as determined by X-ray diffraction) with a set of genes coding for proteins devoid of alpha helices. The first set has periodic oscillations of large amplitude, with an 11-bond period, while the second has none. Furthermore, I analysed a large number of sets of homologous genes from several different species. They exhibit very different amplitudes of oscillations. Altogether, the data with their statistical analyses strongly suggest that the nucleotide oscillations are due to the ‘genomic style of proteins’, which means that homologous proteins, having the same biochemical function in different organisms, may have different secondary structures or may use different ways to be constructed. I realize that this idea is a heterodox one, but I believe that it can shed a new light both on phylogenies and on constraints between proteins and their coding sequences. To cite this article: P.P. Slonimski, C. R. Biologies 330 (2007). [Copyright &y& Elsevier]

Techniques such as detrended fluctuation analysis (DFA) and its extensions have been widely used to determine the nature of scaling in nucleotide sequences. In this brief communication we show that tandem repeats which are ubiquitous in nucleotide sequences can prevent reliable estimation of possible long-range correlations. Therefore, it is important to investigate the presence of tandem repeats prior to scaling exponent estimation. [ABSTRACT FROM AUTHOR]

The enteroviruses (EV), RNA viruses belonging to the Picornaviridae family, have a high genetic variability due to the absence of the efficient proofreading and post replicative repair activities associated with the RNA polymerase. In the present work, we studied the genetic and the antigenic variability of ECHO virus types 11 (E11) and 30 (E30), which are the most isolated echoviruses serotypes in clinical and environmental samples. We established on the 3′ end of the VP1 gene, consensus sequences of E11 and E30 by alignment of 67 E11 and 247 E30 published sequences in GenBank. Our results of sequences comparison showed that the majority of the mutational sites are situated on the third nucleotide of the codon. These mutations were without consequence on the antigenic sequences of the VP1 protein. Thus, E11 and E30 have a high genetic variability (1/3 of the nucleotides are variable), but a relative antigenic conservation. The analysis of the intertypic antigenic variability between E11 and E30 was obtained by the alignment of the corresponding amino acids sequences relative to the N-terminal part of the VP1 protein. Two discriminating parts were highlighted, probably representing antigenic sites for neutralisation antibodies. [ABSTRACT FROM AUTHOR]

Integr8 (http://www.ebi.ac.uk/integr8/) is providing an integration layer for the exploitation of genomic and proteomic data by drawing on databases maintained at major bioinformatics centres in Europe. Main aims are to store the relationships of biological entities to each other and to entries in other databases, to provide a framework that allows for new kinds of data to be integrated, and to offer an entity-centric view of complete genomes and proteomes. Basic tools for data integration comprise the Proteome Analysis database, the International Protein Index (IPI), the Universal Protein sequence archive (UniParc) and the Genome Reviews. Entry points for the Integr8 portal depend on the users entity of interest: from browsing the taxonomy or with a predetermined species of interest, the species page can be used, and a simple search page leads to different applications when looking for certain protein sequences or genes. Customisable statistics data are available from the BioMart application, and pre-prepared data can be downloaded from the FTP site. [ABSTRACT FROM AUTHOR]

Abstract Isolates of Zucchini yellow mosaic virus were obtained from different cucurbit crops in Hangzhou city, China. The complete nucleotide sequences of four isolates and the 3′-terminal sequences, including the coat protein coding region, of four others were determined and then compared with other available sequences. Phylogenetic analysis of the coat protein nucleotide sequences showed that these isolates fell into three significant groups, one of which (designated group III) consisted exclusively of Chinese isolates and is reported for the first time. Comparisons over the completely sequenced genomes showed that, typically for potyviruses, the 5′-end of the genome was usually the most variable but that the group III isolate differed from the others most significantly in the N-terminal part of the coat protein. Partially sequenced group III isolates also varied from other isolates in this region. Group III isolates appear to differ biologically from the other isolates because they do not cause symptoms in watermelon fruit but induce more severe symptoms on the watermelon leaves. [ABSTRACT FROM AUTHOR]

Abstract Conserved carlavirus and potyvirus primers were used in reverse transcriptase-polymerase chain reaction (RT-PCR) to amplify virus fragments from Chinese narcissus (Narcissus tazetta var. chinensis ) in China and the fragments were subsequently sequenced and compared in phylogenetic analyses. Samples from Fujiang province and Shanghai contained either one or two potyviruses and a carlavirus. One potyvirus (PY1) showed a distant relationship to Iris severe mosaic virus, Onion yellow dwarf virus and Shallot yellow stripe virus, while the other (only in the Fujiang sample, PY2) was most closely related to Turnip mosaic virus (TuMV). Similar experiments using glasshouse grown Narcissus originating from the UK contained Ornithogalum mosaic virus and another potyvirus (PY3) in the TuMV/PY2 cluster. Comparisons with previously determined sequence fragments indicated that PY2 was probably Narcissus yellow stripe virus and PY3 Narcissus late season yellow virus. Carlavirus fragments from both Chinese sites seemed to be of the same virus, which was most closely related in phylogenetic analyses to Potato virus M, Aconitum latent virus and Hop latent virus. It is most probably a new member of the genus Carlavirus and has been tentatively named Narcissus common latent virus. [ABSTRACT FROM AUTHOR]

Macrophages express both CXCR4 and CCR5 coreceptors, but restrict X4 HIV-1 replication unless the Env-V3 region, a major determinant of cell tropism, is exchanged with that of R5 HIV-1. As the V3 exchange concomitantly alters the nucleotide sequences, we introduced silent mutations in the V3 or C2 region of macrophage-tropic R5 JRFL without changing the amino acids. Immunoblot analysis confirmed that viral proteins including Env-gp120 were similarly incorporated in wild-type (wt) and mutant virions. The silent mutants infected CCR5-positive MAGIC5 cells but not CCR5-negative MAGI cells, as productively as wt viruses, indicating that the silent mutations did not alter coreceptor utilization. In contrast, two of three silent V3-mutant viruses failed to replicate efficiently in primary macrophages, whereas other V3- or C2-mutants and wt JRFL infected macrophages productively. Furthermore, synthesis of the full-length viral DNA of the aberant V3-mutant was largely reduced in macrophages. These results suggest that V3 nucleotide sequences may be one of the postentry factors restricting HIV-1 replication in macrophages. [Copyright &y& Elsevier]

The phylogeny of green sulfur bacteria was studied on the basis of gene sequences of the 16S rRNA and of the Fenna-Matthews-Olson (FMO) protein. Representative and type strains (31 strains total) of most of the known species were analyzed. On the basis of fmoA gene sequences from Chlorobium tepidum ATCC 49652T and Chlorobium limicola DSM 249T available from the EMBL database, primers were constructed that allowed sequence analysis of a major part of the fmoA gene. The largely congruent phylogenetic relationship of sequences of the fmoA gene and of 16S rDNA gives considerable support to the phylogeny of green sulfur bacteria previously suggested on the basis of 16S rDNA sequences. Distinct groups of strains were recognized on the basis of 16S rDNA and FMO sequences and supported by characteristic signature amino acids of FMO. Marine strains formed clusters separate from freshwater strains. The resulting phylogenetic grouping and relationship of the green sulfur bacteria do not correlate with their current taxonomic classification. [ABSTRACT FROM AUTHOR]

Abstract Background and Aims: Much is still unknown about the clinical significance of TT virus (TTV), which has been reported as a candidate for non A–G hepatitis virus. The aim of this study was to clarify the clinical significance of TTV in patients coinfected with TTV and hepatitis C virus (HCV). Methods: The 95 subjects studied had chronic hepatitis C (CHC), and underwent interferon (IFN) therapy. TT Virus DNA was detected by using polymerase chain reaction. The nucleotide sequences were determined by using a dideoxy chain termination method. A phylogenetic tree was drawn up by using the neighbor-joining method. Results: TT Virus DNA was detected in 37.9% of patients with the use of an open reading frame 1 (ORF1) primer, and in 88.4% of patients by using a 5′ untranslated region (5′ UTR) primer. Using both sets of primers, no differences were found between TTV-DNA-positive and -negative subjects with CHC in the clinical findings. Serum TTV DNA was eradicated in 30.6% of patients with the ORF1 primer, and in 19.1% of patients with the 5′ UTR primer at 6 months after the cessation of IFN therapy. The levels of TTV DNA before IFN therapy were significantly lower in the viral eradication group than in non-eradication group. The changes in alanine aminotransferase (ALT) concentrations were significantly correlated with changes in HCV-RNA in CHC patients with TTV. Moreover, there was no correlation between the changes in TTV DNA and the course of ALT. Conclusion: Hepatocellular injury in patients with chronic hepatitis who are coinfected with HCV and TTV appears to primarily be caused by HCV and is less attributable to TTV. [ABSTRACT FROM AUTHOR]

The 3231-nucleotide-pair (ntp) sequence of one end of one of the two linear mitochondrial (mt) DNA molecules of Hydra attenuata (phylum Cnidaria, class Hydrozoa, order Anthomedusae) has been determined. This segment contains complete genes for tRNAf-Met, l-rRNA, tRNATrp, subunit 2 of cytochrome c oxidase (COII), subunit 8 of ATP synthetase (ATPase8), and the 5′ 136 ntp of ATPase6. These genes are arranged in the order given and are transcribed from the same strand of the molecule. As in two other cnidarians, the hexacorallian anthozoan Metridium senile and the octocorallian anthozoan Sarcophyton glaucum, the mt-genetic code of H. attenuata is near standard. The only modification appears to be that TGA specifies tryptophan rather than termination. Also as in M. senile and S. glaucum, the encoded H. attenuata mt-tRNAf-Met has primary and secondary structural features resembling those of Escherichia coli initiator tRNAt-Met. As the encoded mt-tRNATrp cannot be folded into a totally orthodox secondary structure, two alternative forms are suggested. The encoded H. attenuata mt-l-rRNA is 1738 nt, which is 451 nt shorter than the M. senile mt-l-rRNA. Comparisons of secondary structure models of these two mt-l-rRNAs indicate that most of the size difference results from loss of nucleotides in the H. attenuata molecule at a minimum of 46 locations, which includes elimination of six distinct helical elements. [ABSTRACT FROM AUTHOR]