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Genomics

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Microbiological analysis and whole-genome sequencing of Neisseria gonorrhoeae from the microbiological failures in the international, zoliflodacin, phase 3, clinical trial for treatment of uncomplicated urogenital gonorrhoea: a retrospective, genomic, observational study.

BACKGROUND: Zoliflodacin, a first-in-class oral bacterial, DNA gyrase (GyrB) inhibitor, showed non-inferiority to ceftriaxone combined with azithromycin in a recent large international, phase 3, randomised controlled trial for treatment of uncomplicated urogenital gonorrhoea. The aim of this study was to describe the microbiological and whole-genome sequencing (WGS) analyses of paired baseline (pre-treatment) and test-of-cure (TOC) gonococcal isolates from the zoliflodacin phase 3, randomised controlled trial to further characterise and evaluate the protocol-specified microbiological failures with zoliflodacin (n=22) or ceftriaxone and azithromycin (n=1). METHODS: In this retrospective, genomic, observational study, results from antimicrobial susceptibility testing (agar dilution method) of isolates (n=960; 936 baseline isolates from 763 participants and 24 TOC isolates [23 with a paired baseline isolate in the same anatomical site] from 20 participants) collected during the zoliflodacin phase 3, randomised controlled trial done in 16 outpatient clinics in Belgium, the Netherlands, South Africa, Thailand, and the USA (Nov 6, 2019-March 16, 2023) are described. WGS analysis was performed on paired baseline and TOC isolates from participants with microbiological failures (zoliflodacin 44 isolates [19 participants]; ceftriaxone and azithromycin two isolates [one participant]), and the three baseline isolates with highest zoliflodacin minimum inhibitory concentration (MIC 0·5 mg/L). FINDINGS: All isolates were inhibited by the same zoliflodacin concentrations (MICs ≤0·008 to 0·5 mg/L) as wild-type strains cultured internationally in 2013-23. In participants with a microbiological failure after zoliflodacin treatment (n=22, 19 participants), zoliflodacin MIC values for baseline and TOC isolates were similar, and resistance selection was lacking. WGS showed that five (23%) of 22 infections (95% CI 10-43 [in four participants]) of zoliflodacin microbiological failures had different strains at TOC versus baseline. In 17 zoliflodacin microbiological failures (15 participants), isolates at baseline and TOC were indistinguishable. 13 of these 17 microbiological failures, corresponding to 59% (95% CI 39-77; 13 of 22) of all zoliflodacin microbiological failures, were in urogenital or rectal sites in 11 participants and the isolates had zoliflodacin MICs less than or equal to 0·008 to 0·25 mg/L. The single microbiological failure after ceftriaxone and azithromycin treatment had different strains at TOC versus at baseline. No sequenced isolates had mutations associated with elevated zoliflodacin MICs. INTERPRETATION: In the zoliflodacin phase 3, randomised controlled trial, 23% of the zoliflodacin microbiological failures and the single ceftriaxone and azithromycin microbiological failure had different gonococcal strains at TOC versus baseline, which suggests reinfections and not treatment failures. In addition, 59% of the zoliflodacin microbiological failures, all in anogenital sites, had no obvious microbiological explanation based on the low zoliflodacin MICs, previous pharmacodynamic studies, and no evidence of resistance selection after zoliflodacin therapy. A reinfection as the cause for these microbiological failures could not be excluded. We recommend that WGS is implemented in future randomised controlled trials for gonorrhoea treatment to further evaluate possible microbiological failures, exclude reinfections (to avoid underestimating the cure rates), and characterise antimicrobial resistance determinants. FUNDING: GARDP through grants from Germany BMFTR (03KA1831), UK DHSC as part of GAMRIF, Japan MHLW, the Netherlands' Ministry of Health, Welfare and Sport and Directorate-General for International Cooperation, the Federal Office of Public Health of Switzerland, the Canton of Geneva, Switzerland, and Örebro University Hospital, Sweden.

Humans

The large mitochondrial genome of Syndiclis anlungensis (Lauraceae): Genome structure, comparative analysis, and phylogenetic relationships among Syndiclis species.

The complete mitochondrial genome (mitogenome) of Syndiclis anlungensis, a critically endangered tropical tree, was determined in this study. The mitogenome spans 2,368,454&#xa0;bp across four contigs and harbors 41 protein-coding genes, 22 tRNA genes, and three rRNA genes. Potential mutation regions, including 1317 repeat sequences and 698 simple sequence repeats (SSRs), were accurately located in the S. anlungensis mitogenome. Sixty-five transferred fragments of the repeats were found between its mitochondrial and chloroplast genomes. When compared to three other Laurales mitogenomes, extensive gene order shuffling is evident, leaving only five conserved gene clusters intact. Codon usage analysis reveals a pronounced A/T bias in both mitochondrial and chloroplast genes, and three mitochondrial genes (atp9, rps19, and sdh3) stand out for their high divergence across eleven Syndiclis taxa. Selection analyses indicate strong purifying pressure on rpl2, rpl16, and sdh3 (Ka/Ks&#xa0;<&#xa0;1), with no positive selection detected. Using 41 mitochondrial protein-coding gene sequences from sixteen and three individuals of Syndiclis and Beilschmiedia species, respectively, our phylogenetic tree recovers Syndiclis as monophyletic, with two well-supported clades: one includes S. anlungensis, S. chinensis, S. lotungensis, S. marlipoensis, and a putative new Syndiclis species from Yunnan; the other contains S. furfuracea, S. hongkongensis, S. kwangsiensis, and three putative new Syndiclis species from Guangdong and Vietnam.

Genome, Mitochondrial

Whole-genome phenotype prediction with machine learning: open problems in bacterial genomics.

MOTIVATION: How can we identify causal genetic mechanisms governing bacterial traits? Initial efforts entrusting machine learning models to handle the task of predicting phenotype from genotype yield high accuracy scores. However, attempts to extract meaningful interpretations from the predictive models are found to be corrupted by falsely identified 'causal' features. Relying solely on pattern recognition and correlations is unreliable, significantly so in bacterial genomics settings where high-dimensionality and spurious associations are the norm. Though it is not yet clear whether we can overcome this hurdle, significant efforts are being made towards discovering potential high-risk bacterial genetic variants. In view of this, we set up open problems surrounding phenotype prediction from bacterial whole-genome datasets and extending those approaches to learning causal effects, and discuss challenges that impact the reliability of a machine's decision-making when faced with datasets of this nature. RESULTS: We identify major sources of non-injectivity in the formulation of the genotype-to-phenotype mapping function-linkage-disequilibrium, limited sampling, information loss in representations, unmeasured confounders and observational noise-and analyse their implications for machine learning applications. Using a collection of 4,140 Staphylococcus aureus isolates, we illustrate challenges surrounding the defined open problems. AVAILABILITY AND IMPLEMENTATION: Raw sequencing data are available from the European Nucleotide Archive (ENA) under project accessions ERP001012, PRJEB3174, PRJEB2655, PRJEB2756, and PRJEB2944. Assemblies and annotations were generated with the Sanger bacterial pipeline (https://github.com/sanger-pathogens/vr-codebase) and unitigs extracted using DBGWAS (https://gitlab.com/leoisl/dbgwas).

Machine Learning

Characterization of the genome of molluscum contagiosum virus type 1 between the genome coordinates 0.045 and 0.075 by DNA nucleotide sequence analysis of a 5.6-kb HindIII/MluI DNA fragment.

The complete DNA nucleotide sequence of a HindIII/MluI genomic DNA fragment (0.045-0.075 viral map units) from molluscum contagiosum virus type 1 (MCV-1) was determined. The HindIII/MluI DNA fragment comprises 5,646 bp with a base composition of 64.4% G + C and 35.6% A + T. The DNA sequence contains many perfect direct repeats. A cluster of three repetitive DNA elements R1, R2 and R3, with a complex structural arrangement was detected between nucleotide positions 1802 and 2107. The unit length (box) of the repetitive DNA sequences was found to be 6 bp (15 boxes) and 9 bp (24 boxes) for R1 and R2, respectively. The repetitive DNA element R3 is organized in fifteen boxes (15 bp) in which a unit length of R1 is combined with a unit length of R2. The arrangement of the repetition R3 within the DNA sequences of this particular region of the MCV-1 genome was found to be (5 x R3) + (2 x R2) + (1 x R3) + (6 x R2) + (1 x R3) + (1 x R2) + (8 x R3). Twenty-three open reading frames (ORFs) of 60-1,175 amino acid (AA) residues were detected. The largest ORF (number 17) comprises 1,175 AA with a predicted molecular weight of 126 kD. This ORF harbors a promoter signal which is located 21 nucleotides upstream from the start codon and is very similar to the early promoter signals known for vaccinia virus. This putative protein contains glutamine-enriched regions between AA residues 427 and 682 which show homologies to the corresponding glutamine-enriched regions of a variety of cellular genes like human transcriptional initiation factor (TFIID: TATA box factor).

Amino Acid Sequence

Global genomic and antimicrobial resistance profiling of Neisseria gonorrhoeae: Insights from whole genome sequencing and minimum inhibitory concentration analysis.

BACKGROUND: The rising antimicrobial resistance (AMR) of Neisseria gonorrhoeae is a major global health concern that limits treatment options and complicates disease management. Efflux pump systems and resistance genes are key to bacteria's ability to evade antibiotics. This study examined the genetic and phenotypic resistance landscape using a large dataset of whole-genome sequences to identify key resistance mechanisms, assess efflux pump gene prevalence, and analyze regional variations in Minimum Inhibitory Concentration (MIC) values to inform treatment strategies and public health interventions. METHODS: A total of 38,585 whole-genome sequences of N. gonorrhoeae were analyzed to identify AMR determinants. This study focused on the presence and distribution of efflux pump genes (mtrC, farB, norM, and mtrA) and specific resistance genes, including tet(C) (tetracycline resistance) and aph(3')-Ia (aminoglycoside resistance). The MIC values were assessed for multiple antibiotics to evaluate resistance trends and regional variations, including penicillin, spectinomycin, zoliflodacin, gentamicin, and fluoroquinolones. RESULTS: This analysis revealed widespread resistance to multiple antibiotics. Efflux pump genes (mtrC, farB, norM, and mtrA) were found in nearly all isolates, highlighting their essential roles in resistance and adaptation. The presence of tet(C) and aph (3')-Ia varied across different Gene Presence Patterns, suggesting that regional or therapeutic factors may influence tetracycline and aminoglycoside resistance. High MIC values for penicillin were observed, likely because of blaTEM, a beta-lactamase gene responsible for beta-lactam resistance. Resistance to spectinomycin is also widespread, raising concerns about the diminishing efficacy of this antibiotic. In contrast, zoliflodacin, gentamicin, and fluoroquinolones exhibited relatively low MIC values, indicating their sustained effectiveness against N. gonorrhoeae. DISCUSSION: Efflux pump systems are key to N. gonorrhoeae resistance and adaptability. Regional MIC variations indicate that local antibiotic use shapes resistance patterns. The high resistance to penicillin and spectinomycin highlights the need for alternative treatments, whereas zoliflodacin and fluoroquinolones remain effective but require monitoring. This study emphasizes global AMR surveillance, novel therapies, and targeted antimicrobial stewardship to address multidrug-resistant infections.

Neisseria gonorrhoeae

De Novo Whole Genome Assemblies of Unusual Case-Making Caddisflies (Trichoptera) Highlight Genomic Convergence in the Composition of the Major Silk Gene (h-fibroin).

Trichoptera (caddisflies) is one of the most species-rich orders of aquatic insects. Species of caddisflies cover a broad ecological diversity as exemplified by various uses of underwater silk secretions. Diversity of silk use generally aligns with the evolution of major caddisfly lineages, specifically at the subordinal level: Annulipalpia (retreat makers) and Integripalpia (cocoon and tube-case makers). However, silk use within suborders differs for a few exceptional species in these clades. In this study, we provide the first whole genome assemblies and annotations for two unusual Integripalpia species: Limnocentropus insolitus, whose hard tube-case is anchored to boulders by a rigid, elongated silken stalk, and Phryganopsyche brunnea which builds a "floppy" cylindrical case that lacks the typical robustness of tube-cases. Its texture rather resembles that of the flexible retreats built by Annulipalpia. Using the two high-quality genome assemblies, we identified and annotated the major silk gene, h-fibroin, and compared its amino acid composition across various groups, including retreat, cocoon, and tube-case makers. Our phylogenetic analysis confirmed the phylogenetic position of the two species in the tube-case-making clade. The major silk gene of L. insolitus shows a similar amino acid composition to other tube-case-making species. In contrast, the amino acid composition of P. brunnea resembles that of retreat-making species, in particular with regard to the high content of proline. This is consistent with the hypothesis that proline could be linked to enhanced extensibility of silk fibers. Taken together, our results underscore the role of silk genes in shaping the evolutionary ecology of retreat- and tube-case-making in caddisflies.

Animals

Genomic insights into end-use grain quality and nutritional traits of an ancient Indian dwarf wheat ( Triticum sphaerococcum Percival) population using a multi-locus genome-wide association study.

BACKGROUND: Triticum sphaerococcum, an ancient hexaploid wheat species, is renowned for its stress resilience and superior nutritional quality. A panel of 116&#x2009;T. sphaerococcum accessions (the largest known collection at a single site globally), with six bread wheat released varieties, was evaluated for its potential for genetic quality improvement. Field experiments were conducted under standard, heat and moisture-deficit conditions across two cropping seasons for ten grain end-use quality and nutritional traits. RESULTS: Genotypes showed highly significant differences (P&#x2009;&#x2264;&#x2009;0.001) for measured traits, with high broad-sense heritability resulting from substantial genotypic variance contributions. Triticum sphaerococcum consistently outperformed T. aestivum across environments, with moisture-deficit stress proving more detrimental to quality parameters than heat stress, while micronutrient content increased under stressed conditions. Trait correlations revealed that the gluten index (GI) correlated negatively with the grain hardness index (GHI), wet gluten (WG), and water-binding capacity (WB), while positively correlating with dry gluten (DG) and protein content (PRO), whereas grain iron (GFE), zinc (GZN), and protein showed consistent positive interrelationships. Two superior accessions, PAUTS10 (WG 35.13%, DG 13.71%, PRO 16.42%, GZN 50.89&#x2009;ppm) and Sonamoti (WG 33.33%, DG 12.92%, PRO 16.27%, GZN 56.03&#x2009;ppm), were identified, surpassing the best check variety HD3226 for quality and nutritional parameters. Multi-locus genome-wide association studies identified 30 stable quantitative trait nucleotides across environments, with candidate gene analysis revealing genes involved in transcription regulation, biosynthetic processes, metal ion homeostasis, and transport. CONCLUSIONS: Triticum sphaerococcum demonstrated superior grain quality and micronutrient potential compared with modern wheat, highlighting its value as a genetic resource for biofortification. The identification of elite accessions and stable quantitative trait nucleotides (QTNs) provides useful targets for breeding programs aimed at improving protein and micronutrient content. Integrating ancient germplasm with modern genomic tools can accelerate the development of nutritionally enhanced wheat varieties. &#xa9; 2026 Society of Chemical Industry.

Triticum

Identification of four genomic loci highly related to casein-kinase-2-alpha cDNA and characterization of a casein kinase-2-alpha pseudogene within the mouse genome.

Using the coding region of the human CK-2 alpha cDNA as a probe for screening a genomic mouse library, positive clones representing four different genomic loci were isolated. Partial DNA sequences of these loci encompassing the first 120 nucleotides of the putative coding region are reported. One positive clone was further analyzed by sequencing a 3.1 kb XbaI fragment. This clone displays the characteristics of a pseudogene, i.e. lack of introns and several nucleotide insertions and deletions. In its 3' region it contains a 91 bp large CT-rich stretch which consists of (CCTT) and (CT) repeats; in the 5' region three (CCCCCT) repeats.

Animals

A genome-wide association study identified 10 novel genomic loci associated with intrinsic capacity.

BACKGROUND: Intrinsic capacity (IC) is a multidimensional concept within the World Health Organization framework for healthy aging. It refers to the composite of an individual's physical and mental capacities that enable them to maintain well-being, functional ability, and engagement in valued activities throughout life. While substantial evidence supports the biological basis of IC and its subdomains, the extent to which genetic factors influence IC remains largely unexplored, with no studies currently available. METHODS: Using datasets from the UK Biobank (UKB; N&#x2009;=&#x2009;44 631) and the Canadian Longitudinal Study on Aging (CLSA; N&#x2009;=&#x2009;13 085), we implemented the restricted maximum likelihood method to estimate SNP-based heritability (h2snp), followed by a Genome-Wide Association Study (GWAS) to identify genetic variants associated with IC, and post-GWAS analyses to pinpoint biological implications. RESULTS: The h2snp for IC was estimated at 25.2% in UKB and 19.5% in CLSA. Our GWAS identified 38 independent SNPs for IC across 10 genomic loci and 4289 candidate SNPs, mapped to 197 genes. Post-GWAS analysis revealed the role of these genes in cellular processes such as cell proliferation, immune function, metabolism, and neurodegeneration, with high expression in muscle, heart, brain, adipose, and nerve tissues. Of the 52 traits tested, 23 showed significant genetic correlations with IC, and a higher genetic loading for IC was associated with higher IC scores. CONCLUSIONS: Overall, this study provides comprehensive evidence on the genetic architecture of IC, identifying novel genetic variants and biological pathways, advancing our current knowledge and laying the foundation for ongoing and future research on healthy aging.

Adult

Selective enrichment of a large size genomic DNA fragment by affinity capture: an approach for genome mapping.

A method to enrich large size DNA fragments obtained by digestion with rare cutting restriction endonucleases was developed and applied for the isolation of a 150 kb SfiI fragment containing the beta-globin gene cluster. The digested DNA is rendered single stranded at the ends by diffusing a strand specific exonuclease into an agarose plug containing DNA. The plug is melted and solution hybridization is then performed with a bridge RNA containing specific sequences from the end of a desired fragment linked to a common probe sequence. The common probe sequence is annealed to a biotinylated RNA and the resulting tripartite hybrid is retained onto a solid matrix containing avidin and specifically released by ribonuclease action. Enrichments of greater than 350 fold have been achieved consistently. Such directed purification of large DNA fragments without cloning can considerably expedite mapping and gene localization in a complex genome and facilitate the construction of sublibraries from defined regions of the genome.

Base Sequence

Analysis of the genome of the five Bifidobacterium breve strains: plasmid content, pulsed-field gel electrophoresis genome size estimation and rrn loci number.

The genomes of the five Bifidobacterium breve strains available from culture collections were compared by restriction endonuclease analysis. Electrophoretic migration of undigested DNA allowed us to detect a 5.6-kb circular plasmid in two of these strains. A restriction map of this plasmid was constructed using 10 enzymes. With DraI endonuclease, pulsed-field gel electrophoresis has allowed the determination of the five B. breve genome sizes to 2.1 Mb. This estimation was further confirmed for CIP 6469 (type strain) and ATCC 15698 using XbaI and SpeI enzymes. In addition, rRNA gene regions were used as probes for strain characterization and suggest that there are at least three rrn loci in B. breve.

Bifidobacterium

Genomic introgressions from wild relatives in the wheat genome alter meiotic dynamics in inter-varietal hybrids.

The use of wild relatives to introduce original diversity in the genome of bread wheat (Triticum aestivum L.) is an interesting approach to face the challenges of sustainable agriculture and the impact of climate change on wheat production. However, the influence of these wild-species introgressions on meiosis in inter-varietal wheat hybrids remains poorly understood. We analyzed the French wheat variety Renan (Re) carrying Aegilops ventricosa (Aev)-derived 2AS/2NS and 7DL/7DvL introgressions, the reference cultivar Chinese Spring (CS), which lacks these introgressions, and their inter-varietal hybrid Chinese Spring &#xd7; Renan (CSRe). This analysis combined cytogenetic approaches with the assessment of reproductive performance. Furthermore, we generated a cytological atlas of meiosis in wild tetraploid Aev, quantifying bivalent configurations and chiasma frequency. We observed a reduced pollen viability and a slight decrease in floret fertility in the hybrid CSRe. Exploration of the meiotic behavior showed that CSRe exhibited increased numbers of rod bivalents and univalents, leading to a reduced average chiasma number and frequent chromosome bridges and fragmentations, whereas the parental lines maintained stable chromosome pairing. These rearrangements indicate that homologous chromosome pairing and recombination are affected in CSRe. We applied introgression-specific oligo-Fluorescent In Situ Hybridization to localize alien segments in CSRe, providing a novel strategy to investigate the meiotic behavior of introgressed regions. The 2AS/2NS introgressed segments in CSRe were frequently located on rod bivalents or univalents, while 7DL/7DvL segments consistently formed ring bivalents. Our results provide a foundation for guiding alien gene introgression and for understanding the behavior of chromosomes with introgressions in the wheat genome.

Meiosis

Intestinal calcium transport in mole-rats (Cryptomys damarensis and Heterocephalus glaber) is independent of both genomic and non-genomic vitamin D mediation.

The role of vitamin D in mineral uptake in the gastrointestinal tract (GIT) of mole-rats (Heterocephalus glaber and Cryptomys damarensis; family Bathyergidae), animals with a naturally impoverished vitamin D status, was investigated. We measured relative rates of passage of radioactive markers, mode of calcium (Ca) uptake, paracellular movement and the opening of voltage-sensitive Ca channels (VSCCs) along the GIT with and without oral vitamin D3 supplementation. The ratio of relative absorption of labelled 45Ca to [14C]polyethylene glycol ([14C]PEG) indicated that within 24 h more than 88% of the Ca in the diet had been absorbed. Most absorption occurred in the duodenum within 12 h. The contribution of the hindgut (caecum and proximal and distal colon) to total Ca absorption was small (approximately 11%). Only passive uptake occurred in the duodenum (serosal (S): mucosal (M) ratios approximately 1). Active uptake occurred in the hindgut (S:M > 2), although hindgut absorption appears to play a secondary role to passive uptake in the duodenum. Vitamin D3 supplementation had no effect on the mode of Ca uptake in either the small intestine or the hindgut. Although we found VSCCs in mole-rat intestinal epithelial cells, they occurred in very low concentrations. Calcium influx through VSCCs did not change following vitamin D stimulation. Furthermore, mole-rats pretreated with intraperitoneal (I.P.) 1,25(OH)2D3 showed no enhancement of VSCC Ca uptake, indicating that active uptake plays a minor role, if any, in GIT mineral absorption. Our data support the hypothesis that intestinal Ca transport in mole-rats is independent of both genomic and non-genomic vitamin D mediation.

Animals

The genomics of long tandem arrays of satellite DNA in the human genome.

At least 10% of DNA in the human genome consists of long arrays of repeated sequences, arranged in tandem head-to-tail arrays in a number of discrete, highly localized chromosomal regions. Different families of these so-called "satellite DNA" sequences have been defined, organized in diverged subsets on different chromosomes. The molecular, cytogenetic, and evolutionary analysis of the hierarchical organization of such sequences in the human and other complex genomes encompasses a variety of approaches, including chromosomal mapping, in situ hybridization, genetic linkage analysis, long-range restriction mapping, and DNA sequencing. Investigation of the organization of satellite arrays constitutes a necessary first step towards eventual elucidation of the origin, evolution, and maintenance of these sequences and their contribution to the structure and behavior of human chromosomes.

Chromosome Mapping

Natural Selection Drives Codon Usage Bias in the Mitochondrial Genome of Ligula intestinalis (Linnaeus, 1758) Gmelin, 1790 (Cestoda: Diphyllobothriidea): Insights from Comparative Genomics and Optimal Codon Identification.

Codon usage bias (CUB) is a useful indicator of evolutionary forces shaping mitochondrial genomes. Codon usage bias in mitochondrial genomes of Diphyllobothriidae and especially in Ligula intestinalis was characterized. The roles of natural selection and mutation pressure in framing this bias were evaluated on the basis of 12 protein-coding genes in Diphyllobothriidae. The complete mitogenome (13,725 bp) of L. intestinalis comprises 12 protein-coding genes (PCGs), 22 tRNAs, and two rRNAs, all positioned on the heavy strand, and contains an overall AT content of 66.15%. The mean CAI (0.176), CBI (-0.105), and ENC (45.33) and an evident preference for U-ending codons observed in all examined genes indicate weak CUB. Neutrality, ENC, and PR2 plots consistently demonstrate that natural selection is the predominant force driving CUB and contributes approximately 56% in L. intestinalis and 83% in other Diphyllobothriidea species, with mutation pressure playing a secondary role. Phylogenetic reconstruction supported the monophyly of Diphyllobothriidea, confirmed the paraphyly of Diphyllobothrium as traditionally defined, and placed Ligula and Digramma as sister taxa. These findings clarify the evolutionary constraints governing codon usage in cestode mitogenomes and provide practical resources for codon optimization in heterologous gene expression and genetic studies of this economically important parasite.

Diphyllobothriidea

[Study of the structure-function organization of the variola virus genome. IV. Sequencing and analysis of the nucleotide sequence of the right terminus of the India-1967 strain genome].

Sequencing and computer analysis of the variola major virus strain India-1967 (VAR-IND) genome segment (53,018 bp) from the right terminal region have been carried out. Fifty nine potential open reading frames (ORFs) of over 60 amino acid residues have been identified. Structure-function organization of VAR-IND DNA segment under study was compared with the previously reported sequences from the analogous genomic regions of vaccinia virus strains Copenhagen (VAC-COP) and Western Reserve (VAC-WR) and variola virus strain Harvey (VAR-HAR). Multiple distinctions in the genetic map of VAR-IND from VAC-COP and VAC-WR have been revealed along with the high similarity to the corresponding VAR-HAR segment. Possible functions of the predicted viral proteins and the effect of their differences on the features of orthopoxviruses are discussed.

Amino Acid Sequence

[A full-size DNA copy of the tick-borne encephalitis virus genome. I. Analysis of the 5'- and 3'-terminal noncoding regions of the genome].

Using reverse transcription and the polymerase chain reaction, cDNA fragments of noncoding regions of the tick-borne encephalitis virus (TBEV) genome were obtained. These fragments were cloned into a pGEM3 vector, and their nucleotide sequences were determined. The heterogeneity of the 3'-terminal untranslated region of the TBEV RNA was revealed. To create a stable full-size DNA copy of the TBEV genome, four cDNA variants differing in length and structure of the 3'-terminal fragment of the viral RNA were cloned into a pBR322-derived vector.

Base Sequence

[Structure-activity organization of the variola virus genome. III. Sequencing and analysis of the nucleotide sequence of the conserved region of HindIII-F, -N-, and -A-fragments of the India 1967 strain genome].

Computer analysis of variola major virus (VAR) genomic fragment bounded by open reading frames (ORFs) D1R and A33L which is 47,961 bp long revealed 46 potential ORFs. The VAR proteins were compared with the analogous proteins of vaccinia virus strain Copenhagen. The subunits of DNA-dependent RNA polymerase, as well as the transcription factors, mRNA capping enzymes, and proteins necessary for the virion morphogenesis proved to be highly conservative within orthopoxviruses. The most pronounced differences between the VAR genome fragment under study and the corresponding vaccinia virus fragment were revealed in the vicinity of the gene encoding the A-type inclusion body protein. The possible functions of the analyzed viral proteins are discussed.

Amino Acid Sequence