Publications by authors named "PENEV P"

RiboVision2 is a web server designed to visualize phylogenetic, structural, and evolutionary properties of ribosomal RNAs simultaneously at the levels of primary, secondary, and three-dimensional structure and in the context of full ribosomal complexes. RiboVision2 instantly computes and displays a broad variety of data; it has no login requirements, is open-source, free for all users, and available at https://ribovision2.chemistry.

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  • - Methanoperedens, a type of archaea, helps reduce methane emissions and hosts unique extrachromosomal genetic elements (ECEs) called Borgs, which influence their activity; however, the diversity of these ECEs has not been thoroughly explored.
  • - New research identifies small linear ECEs, circular viruses, and other unclassified ECEs associated with Methanoperedens, with linear ECEs sharing characteristics with Borgs, prompting the term "mini-Borgs."
  • - Mini-Borgs show significant genetic diversity across at least five groups and are linked to various Methanoperedens viruses, suggesting a complex network of genetic exchange that may affect the functioning and evolution of their host
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All organisms living on Earth descended from a single, common ancestral population of cells, known as LUCA-the last universal common ancestor. Since its emergence, the diversity and complexity of life have increased dramatically. This chapter focuses on four key biological innovations throughout Earth's history that had a significant impact on the expansion of phylogenetic diversity, organismal complexity, and ecospace habitation.

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The Astrobiology Primer 3.0 (ABP3.0) is a concise introduction to the field of astrobiology for students and others who are new to the field of astrobiology.

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The ribosome serves as the universally conserved translator of the genetic code into proteins and supports life across diverse temperatures ranging from below freezing to above 120°C. Ribosomes are capable of functioning across this wide range of temperatures even though the catalytic site for peptide bond formation, the peptidyl transferase center, is nearly universally conserved. Here we find that Thermoproteota, a phylum of thermophilic Archaea, substitute cytidine for uridine at large subunit rRNA positions 2554 and 2555 (Escherichia coli numbering) in the A loop, immediately adjacent to the binding site for the 3'-end of A-site tRNA.

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Anaerobic methanotrophic (ANME) archaea obtain energy from the breakdown of methane, yet their extrachromosomal genetic elements are little understood. Here we describe large plasmids associated with ANME archaea of the Methanoperedens genus in enrichment cultures and other natural anoxic environments. By manual curation we show that two of the plasmids are large (155,605 bp and 191,912 bp), circular, and may replicate bidirectionally.

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  • Bacteriophages are viruses that rely on bacteria to reproduce but some have unique genetic codes that include reassigned stop codons, which are usually not compatible with bacterial translation systems.
  • A study of 9,422 phage genomes revealed that this stop-codon recoding occurs in various phage groups that infect bacteria found in human and animal gut microbiota, especially in genes related to phage structure and cell lysis.
  • The study suggests that these recoded stop codons may help delay the production of late-stage viral proteins, indicating that such changes can evolve quickly within closely related phage lineages.
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The ribosomal protein S21 (bS21) gene has been detected in diverse viruses with a large range of genome sizes, yet its in situ expression and potential significance have not been investigated. Here, we report five closely related clades of bacteriophages (phages) represented by 47 genomes (8 curated to completion and up to 331 kbp in length) that encode a bS21 gene. The bS21 gene is on the reverse strand within a conserved region that encodes the large terminase, major capsid protein, prohead protease, portal vertex proteins, and some hypothetical proteins.

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We have developed the program TwinCons, to detect noisy signals of deep ancestry of proteins or nucleic acids. As input, the program uses a composite alignment containing pre-defined groups, and mathematically determines a 'cost' of transforming one group to the other at each position of the alignment. The output distinguishes conserved, variable and signature positions.

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SH3 and OB are the simplest, oldest, and most common protein domains within the translation system. SH3 and OB domains are β-barrels that are structurally similar but are topologically distinct. To transform an OB domain to a SH3 domain, β-strands must be permuted in a multistep and evolutionarily implausible mechanism.

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ProteoVision is a web server designed to explore protein structure and evolution through simultaneous visualization of multiple sequence alignments, topology diagrams and 3D structures. Starting with a multiple sequence alignment, ProteoVision computes conservation scores and a variety of physicochemical properties and simultaneously maps and visualizes alignments and other data on multiple levels of representation. The web server calculates and displays frequencies of amino acids.

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Widespread testing for the presence of the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in individuals remains vital for controlling the COVID-19 pandemic prior to the advent of an effective treatment. Challenges in testing can be traced to an initial shortage of supplies, expertise, and/or instrumentation necessary to detect the virus by quantitative RT-PCR (RT-qPCR), the most robust, sensitive, and specific assay currently available. Here we show that academic biochemistry and molecular biology laboratories equipped with appropriate expertise and infrastructure can replicate commercially available SARS-CoV-2 RT-qPCR test kits and backfill pipeline shortages.

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Article Synopsis
  • - The ribosome's common core, made up of rRNA and ribosomal proteins, links all living organisms to a shared ancestor, with its rRNA closely resembling that of modern bacteria; in eukaryotes, this rRNA is much larger due to additional segments.
  • - The study reveals that two groups of archaea, Lokiarchaeota and Heimdallarchaeota, have ribosomal RNA that serves as a transition between prokaryotes and eukaryotes, featuring two significant expansion segments (ES9 and ES39) that contribute to their large size.
  • - Through experimental analyses, researchers found unique structural features in Asgard ES39s compared to eukaryotic ES39s, while still demonstrating
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Widespread testing for the presence of the novel coronavirus SARS-CoV-2 in individuals remains vital for controlling the COVID-19 pandemic prior to the advent of an effective treatment. Challenges in testing can be traced to an initial shortage of supplies, expertise and/or instrumentation necessary to detect the virus by quantitative reverse transcription polymerase chain reaction (RT-qPCR), the most robust, sensitive, and specific assay currently available. Here we show that academic biochemistry and molecular biology laboratories equipped with appropriate expertise and infrastructure can replicate commercially available SARS-CoV-2 RT-qPCR test kits and backfill pipeline shortages.

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The ribosome is an ancient molecular fossil that provides a telescope to the origins of life. Made from RNA and protein, the ribosome translates mRNA to coded protein in all living systems. Universality, economy, centrality and antiquity are ingrained in translation.

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Purpose: The aim of this study was to investigate the influence of different ligamentous Lisfranc injuries on computed tomography (CT) findings under weight-bearing and to emphasize the indications for surgical treatment of their various types.

Methods: Sixteen human cadaveric lower limbs were placed in weight-bearing radiolucent frame for CT scanning. All intact specimens were initially scanned, and then, dorsal approach was used for sequential ligaments cutting of: (1) the dorsal and the interosseous (Lisfranc) ligaments between medical cuneiform (MC) and metatarsal 2 (MT2); (2) the plantar ligament between the MC and MT3; (3) the plantar ligament between MC and MT2.

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Mammalian and bird ribosomes are nearly twice the mass of prokaryotic ribosomes in part because of their extraordinarily long rRNA tentacles. Human rRNA tentacles are not fully observable in current three-dimensional structures and their conformations remain to be fully resolved. In previous work we identified sequences that favor G-quadruplexes in silico and in vitro in rRNA tentacles of the human large ribosomal subunit.

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rRNA is the single most abundant polymer in most cells. Mammalian rRNAs are nearly twice as large as those of prokaryotes. Differences in rRNA size are due to expansion segments, which contain extended tentacles in metazoans.

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Functions, origins, and evolution of the translation system are best understood in the context of unambiguous and phylogenetically based taxonomy and nomenclature. Here, we map ribosomal proteins onto the tree of life and provide a nomenclature for ribosomal proteins that is consistent with phylogenetic relationships. We have increased the accuracy of homology relationships among ribosomal proteins, providing a more informative picture of their lineages.

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The Universal Gene Set of Life (UGSL) is common to genomes of all extant organisms. The UGSL is small, consisting of <100 genes, and is dominated by genes encoding the translation system. Here we extend the search for biological universality to three dimensions.

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Metatypical basal cell carcinoma (MTBCC) represents a high-risk type of cutaneous tumour. We report about three different patients with relapsing advanced large MTBCC: one of the scalp and two of the cheek region. Such patients required in most of the cases a complex surgical approach to achieve a stable and complete remission.

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Atypical Mole Syndrome is the most important phenotypic risk factor for cutaneous melanoma, a malignancy that accounts for about 80% of deaths from skin cancer. Since early diagnosis of melanoma is of great prognostic relevance, the identification of Atypical Mole Syndrome carriers (sporadic and familial) is essential, as well as the recommendation of preventative measures that must be undertaken by these patients.We report two rare cases concerning patients with multiple primary skin melanomas in the setting of a familial and a sporadic syndrome of dysplastic nevi: the first patient is a 67-year-old patient with a history of multiple superficial spreading melanomas localized on his back.

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This study examined the effects of recurrent sleep restriction on the plasma metabolome of adults with familial risk of type 2 diabetes. Eleven healthy adults (6M/5F; mean [SD] age: 26 [3]years; BMI 23.5 [2.

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Objective: Short-sleep insomnia is associated with increased risk of diabetes. The role of altered insulin secretion and action in this association is poorly understood.

Design: Observational study.

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