86 results on '"Vladimir Potapov"'
Search Results
2. N 1-methyl-pseudouridine is incorporated with higher fidelity than pseudouridine in synthetic RNAs
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Tien-Hao Chen, Vladimir Potapov, Nan Dai, Jennifer L. Ong, and Bijoyita Roy
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Medicine ,Science - Abstract
Abstract In vitro transcribed synthetic messenger RNAs (mRNAs) represent a novel therapeutic modality. To overcome the inherent immunogenicity, as well as to increase the therapeutic efficacy of the molecules, uridine analogs—such as pseudouridine (Ψ) and N 1-methyl-pseudouridine (m1Ψ), are incorporated in the synthetic mRNA. To decipher the fidelity with which these modifications are incorporated during the in vitro transcription (IVT) process, we compared the incorporation fidelity of uridine analogs with different RNA polymerases. We demonstrate that m1Ψ is incorporated with higher fidelity than Ψ. The fidelity of nucleotide incorporation differs between RNA polymerases; however, the spectrum of mutations observed between the RNAPs is similar. We also show that the array of nucleotide misincorporation is not dependent on the template DNA sequence context and that the distribution of these misincorporated nucleotides is not localized to any specific region along the length of the RNA. Based on our findings, we introduce a novel method to improve uridine analog incorporation fidelity during IVT. Our proof-of-concept experiments for higher-fidelity incorporation of uridine analogs during IVT provide guidelines when choosing RNAPs for the generation of modified uridine-containing mRNAs in vitro.
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- 2022
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3. Geocryological Structure of a Giant Spring Aufeis Glade at the Anmangynda River (Northeastern Russia)
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Vladimir Olenchenko, Anastasiia Zemlianskova, Olga Makarieva, and Vladimir Potapov
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permafrost ,giant spring aufeis ,the Anmangynda river ,ground-penetrating radar ,electrical tomography ,groundwater ,Geology ,QE1-996.5 - Abstract
Gigantic aufeis fields serve as indicators of water exchange processes within the permafrost zone and are important in assessing the state of the cryosphere in a changing climate. The Anmangynda aufeis, located in the upstream of the Kolyma River basin, is present in the mountainous regions of Northeast Eurasia. Recent decades have witnessed significant changes in aufeis formation patterns, necessitating a comprehensive understanding of cryospheric processes. The objective of the study, conducted in 2021–2022, was to examine the structure of the Anmangynda aufeis and its glade, aiming to understand its genesis and formation processes. The tasks included identifying above- and intra-frozen taliks, mapping groundwater (GW) discharge channels, determining permafrost base depth, and assessing ice thickness distribution. Soundings using ground-penetrating radar (GPR), capacitively coupled electrical resistivity tomography (CCERT), and the transient electromagnetic (TEM) method were employed. GW discharge channels originating from alluvial deposits and extending to the aufeis surface within river channels were identified through GPR and verified through drilling. Deep-seated sources of GW within the bedrock were inferred. CCERT data allowed us to identify large and localized frozen river taliks, from which water is forced onto the ice surface. According to the TEM data, the places of GW outlets spatially coincide with the zones interpreted as faults.
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- 2023
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4. A bi-specific lectin from the mushroom Boletopsis grisea and its application in glycoanalytical workflows
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Mehul B. Ganatra, Vladimir Potapov, Saulius Vainauskas, Anthony Z. Francis, Colleen M. McClung, Cristian I. Ruse, Jennifer L. Ong, and Christopher H. Taron
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Medicine ,Science - Abstract
Abstract The BLL lectin from the edible Japanese “Kurokawa” mushroom (Boletopsis leucomelaena) was previously reported to bind to N-glycans harboring terminal N-acetylglucosamine (GlcNAc) and to induce apoptosis in a leukemia cell line. However, its gene has not been reported. In this study, we used a transcriptomics-based workflow to identify a full-length transcript of a BLL functional ortholog (termed BGL) from Boletopsis grisea, a close North American relative of B. leucomelaena. The deduced amino acid sequence of BGL was an obvious member of fungal fruit body lectin family (Pfam PF07367), a highly conserved group of mushroom lectins with a preference for binding O-glycans harboring the Thomsen–Friedenreich antigen (TF-antigen; Galβ1,3GalNAc-α-) and having two ligand binding sites. Functional characterization of recombinant BGL using glycan microarray analysis and surface plasmon resonance confirmed its ability to bind both the TF-antigen and β-GlcNAc-terminated N-glycans. Structure-guided mutagenesis of BGL’s two ligand binding clefts showed that one site is responsible for binding TF-antigen structures associated with O-glycans, whereas the second site specifically recognizes N-glycans with terminal β-GlcNAc. Additionally, the two sites show no evidence of allosteric communication. Finally, mutant BGL proteins having single functional bindings site were used to enrich GlcNAc-capped N-glycans or mucin type O-glycopeptides from complex samples in glycomics and glycoproteomics analytical workflows.
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- 2021
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5. Protein Domain Guided Screen for Sequence Specific and Phosphorothioate-Dependent Restriction Endonucleases
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Thomas Lutz, Honorata Czapinska, Alexey Fomenkov, Vladimir Potapov, Daniel F. Heiter, Bo Cao, Peter Dedon, Matthias Bochtler, and Shuang-yong Xu
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DNA backbone phosphorothioate modification ,PT modification dependent endonucleases ,SBD and HNH domain fusion ,EcoWI endonuclease ,Bsp305I endonuclease ,Microbiology ,QR1-502 - Abstract
Modification dependent restriction endonucleases (MDREs) restrict modified DNA, typically with limited sequence specificity (∼2–4 bp). Here, we focus on MDREs that have an SRA and/or SBD (sulfur binding domain) fused to an HNH endonuclease domain, cleaving cytosine modified or phosphorothioated (PT) DNA. We independently characterized the SBD-SRA-HNH endonuclease ScoMcrA, which preferentially cleaves 5hmC modified DNA. We report five SBD-HNH endonucleases, all recognizing GpsAAC/GpsTTC sequence and cleaving outside with a single nucleotide 3′ stagger: EcoWI (N7/N6), Ksp11411I (N5/N4), Bsp305I (N6/N4-5), Mae9806I [N(8-10)/N(8-9)], and Sau43800I [N(8-9)/N(7-8)]. EcoWI and Bsp305I are more specific for PT modified DNA in Mg2+ buffer, and promiscuous with Mn2+. Ksp11411I is more PT specific with Ni2+. EcoWI and Ksp11411I cleave fully- and hemi-PT modified oligos, while Bsp305I cleaves only fully modified ones. EcoWI forms a dimer in solution and cleaves more efficiently in the presence of two modified sites. In addition, we demonstrate that EcoWI PT-dependent activity has biological function: EcoWI expressing cells restrict dnd+ GpsAAC modified plasmid strongly, and GpsGCC DNA weakly. This work establishes a framework for biotechnology applications of PT-dependent restriction endonucleases (PTDRs).
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- 2020
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6. Enabling one-pot Golden Gate assemblies of unprecedented complexity using data-optimized assembly design.
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John M Pryor, Vladimir Potapov, Rebecca B Kucera, Katharina Bilotti, Eric J Cantor, and Gregory J S Lohman
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Medicine ,Science - Abstract
DNA assembly is an integral part of modern synthetic biology, as intricate genetic engineering projects require robust molecular cloning workflows. Golden Gate assembly is a frequently employed DNA assembly methodology that utilizes a Type IIS restriction enzyme and a DNA ligase to generate recombinant DNA constructs from smaller DNA fragments. However, the utility of this methodology has been limited by a lack of resources to guide experimental design. For example, selection of the DNA sequences at fusion sites between fragments is based on broad assembly guidelines or pre-vetted sets of junctions, rather than being customized for a particular application or cloning project. To facilitate the design of robust assembly reactions, we developed a high-throughput DNA sequencing assay to examine reaction outcomes of Golden Gate assembly with T4 DNA ligase and the most commonly used Type IIS restriction enzymes that generate three-base and four-base overhangs. Next, we incorporated these findings into a suite of webtools that design assembly reactions using the experimental data. These webtools can be used to create customized assemblies from a target DNA sequence or a desired number of fragments. Lastly, we demonstrate how using these tools expands the limits of current assembly systems by carrying out one-pot assemblies of up to 35 DNA fragments. Full implementation of the tools developed here enables direct expansion of existing assembly standards for modular cloning systems (e.g. MoClo) as well as the formation of robust new high-fidelity standards.
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- 2020
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7. Shallow Permafrost at the Crystal Site of Peaceful Underground Nuclear Explosion (Yakutia, Russia): Evidence from Electrical Resistivity Tomography
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Svetlana Artamonova, Alexander Shein, Vladimir Potapov, Nikolay Kozhevnikov, and Vladislav Ushnitsky
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environment research ,peaceful underground nuclear explosion ,electrical resistivity tomography ,permafrost ,geological environment ,natural–technical system ,Technology - Abstract
The site where a peaceful underground nuclear explosion, Crystal, was detonated in 1974, at a depth of 98 m in perennially frozen Cambrian limestones, was studied by electrical resistivity tomography (ERT) in 2019. The purpose of our research, the results of which are presented in this article, was to assess the current permafrost state at the Crystal site and its surroundings by inversion and interpretation of electrical resistivity tomography (ERT) data. Inversion of the ERT data in Res2Dinv verified against ZondRes2D forward models yielded 2D inverted resistivity sections to a depth of 80 m. The ERT images revealed locally degrading permafrost at the Crystal site and its surroundings. The warming effect was caused by two main factors: (i) a damage zone of deformed rocks permeable to heat and fluids, with a radius of 160 m around the emplacement hole; (ii) the removal of natural land cover at the site in 2006. The artificial cover of rock from a nearby quarry, which was put up above the emplacement hole in order to prevent erosion and migration of radionuclides, is currently unfrozen.
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- 2022
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8. PHARMACOLOGICAL CORRECTION OF INTERCEPT HEMODYNAMICS IN ACUTE KIDNEY DAMAGE (PART 1)
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Katherine Shramenko, Georgiy Gorodnik, Valentina Shano, Irina Kuznetsova, Aleksandr Grigorenko, and Vladimir Potapov
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acute kidney injury ,renal blood flow disorders ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Introduction: Development of vasoconstriction of kidney arterioles and reduction of renal blood flow is one of the main mechanism of acute kidney injury (AKI) formation. Methods for evaluation of intrarenal hemodynamics status are rather limited. Evident interest for the clinician is the possibility of rapid and non-invasive assessment of renal hemodynamics using the dopplerography method. The method makes it possible to visualize the kidney vessels and conduct a qualitative and quantitative evaluation of renal blood flow. Peculiarities of disturbed blood flow in the kidneys can determine the individuality of pharmacological correction and intensive care in patients with AKI. Objectives: The aim of our study was to reveal the peculiarities of renal blood flow disorders, depending on the variant, stage and severity of AKI; to evaluate the opportunities of individual pharmacological correction and intensive care in studied AKI patients. Methods: A prospective nonrandomized study. Inclusion criteria: patients with prerenal, renal and subrenal AKI in the stage of oligoanuria and restoration of diuresis; exclusion criteria: AKI patients after cardiac surgery and operations on the large vessels. 250 ICU patients with prerenal (130), renal (81) and subrenal (39) AKI were examinedby ultrasound dopplerography. Results and discussion: Сomparative data of intrarenal blood flow dopplerographic examination in patients with various variants of AKI are presented. All patients initially, at admission in ICU revealed disorders of renal hemodynamics, the severity of which was different depending on the AKI module. During intensive care, as diuresis was restored, the parameters of renal blood flow improved. The speed and completeness of hemodynamics recovery was determined by both the modulus and severity of AKI. The heterogeneity of the prerenal module of AKI was determined due the data of renal blood flow and the rate of restoration of diuresis. So, we divided prerenal module in 2 groups: 1) real (genuine) prerenal AKI and 2) AKI prerenal for reason. The expediency of such selection is substantiated. It was established that resistive index (RI) in the main trunk of the renal artery is an early criterion of severity of AKI (F), and its dynamics during intensive care makes it possible to diagnose the transformation of AKI in chronic renal failure (CRF). Strong direct correlation RI with the duration of oligoanuria (r = 0.72), which is the main retrospective marker of the severity of AKI, was revealed yet upon admission to the ICU. It was found that the peculiarities of renal hemodynamics disturbance are an important criterion for differential diagnosis of the AKI module: renal dopplerometry data significantly (p
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- 2017
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9. Therminator DNA Polymerase: Modified Nucleotides and Unnatural Substrates
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Andrew F. Gardner, Kiserian M. Jackson, Madeleine M. Boyle, Jackson A. Buss, Vladimir Potapov, Alexandra M. Gehring, Kelly M. Zatopek, Ivan R. Corrêa Jr., Jennifer L. Ong, and William E. Jack
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DNA sequencing ,xenonucleic acids ,aptamers ,functionalized DNA ,unnatural base pairs ,Biology (General) ,QH301-705.5 - Abstract
A variant of 9°N DNA polymerase [Genbank ID (AAA88769.1)] with three mutations (D141A, E143A, A485L) and commercialized under the name “Therminator DNA polymerase” has the ability to incorporate a variety of modified nucleotide classes. This Review focuses on how Therminator DNA Polymerase has enabled new technologies in synthetic biology and DNA sequencing. In addition, we discuss mechanisms for increased modified nucleotide incorporation.
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- 2019
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10. Examining Sources of Error in PCR by Single-Molecule Sequencing.
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Vladimir Potapov and Jennifer L Ong
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Medicine ,Science - Abstract
Next-generation sequencing technology has enabled the detection of rare genetic or somatic mutations and contributed to our understanding of disease progression and evolution. However, many next-generation sequencing technologies first rely on DNA amplification, via the Polymerase Chain Reaction (PCR), as part of sample preparation workflows. Mistakes made during PCR appear in sequencing data and contribute to false mutations that can ultimately confound genetic analysis. In this report, a single-molecule sequencing assay was used to comprehensively catalog the different types of errors introduced during PCR, including polymerase misincorporation, structure-induced template-switching, PCR-mediated recombination and DNA damage. In addition to well-characterized polymerase base substitution errors, other sources of error were found to be equally prevalent. PCR-mediated recombination by Taq polymerase was observed at the single-molecule level, and surprisingly found to occur as frequently as polymerase base substitution errors, suggesting it may be an underappreciated source of error for multiplex amplification reactions. Inverted repeat structural elements in lacZ caused polymerase template-switching between the top and bottom strands during replication and the frequency of these events were measured for different polymerases. For very accurate polymerases, DNA damage introduced during temperature cycling, and not polymerase base substitution errors, appeared to be the major contributor toward mutations occurring in amplification products. In total, we analyzed PCR products at the single-molecule level and present here a more complete picture of the types of mistakes that occur during DNA amplification.
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- 2017
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11. Correction: Examining Sources of Error in PCR by Single-Molecule Sequencing.
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Vladimir Potapov and Jennifer L Ong
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Medicine ,Science - Abstract
[This corrects the article DOI: 10.1371/journal.pone.0169774.].
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- 2017
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12. Data-driven prediction and design of bZIP coiled-coil interactions.
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Vladimir Potapov, Jenifer B Kaplan, and Amy E Keating
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Biology (General) ,QH301-705.5 - Abstract
Selective dimerization of the basic-region leucine-zipper (bZIP) transcription factors presents a vivid example of how a high degree of interaction specificity can be achieved within a family of structurally similar proteins. The coiled-coil motif that mediates homo- or hetero-dimerization of the bZIP proteins has been intensively studied, and a variety of methods have been proposed to predict these interactions from sequence data. In this work, we used a large quantitative set of 4,549 bZIP coiled-coil interactions to develop a predictive model that exploits knowledge of structurally conserved residue-residue interactions in the coiled-coil motif. Our model, which expresses interaction energies as a sum of interpretable residue-pair and triplet terms, achieves a correlation with experimental binding free energies of R = 0.68 and significantly out-performs other scoring functions. To use our model in protein design applications, we devised a strategy in which synthetic peptides are built by assembling 7-residue native-protein heptad modules into new combinations. An integer linear program was used to find the optimal combination of heptads to bind selectively to a target human bZIP coiled coil, but not to target paralogs. Using this approach, we designed peptides to interact with the bZIP domains from human JUN, XBP1, ATF4 and ATF5. Testing more than 132 candidate protein complexes using a fluorescence resonance energy transfer assay confirmed the formation of tight and selective heterodimers between the designed peptides and their targets. This approach can be used to make inhibitors of native proteins, or to develop novel peptides for applications in synthetic biology or nanotechnology.
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- 2015
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13. Correction: Comparative Genomics and Drug Resistance of a Geographic Variant of ST239 Methicillin-Resistant Emerged in Russia.
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Tatsuo Yamamoto, Tomomi Takano, Wataru Higuchi, Yasuhisa Iwao, Olga Singur, Ivan Reva, Yuta Otsuka, Toru Nakayashiki, Hirotada Mori, Galina Reva, Vladimir Kuznetsov, and Vladimir Potapov
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Medicine ,Science - Published
- 2012
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14. Comparative genomics and drug resistance of a geographic variant of ST239 methicillin-resistant Staphylococcus aureus emerged in Russia.
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Tatsuo Yamamoto, Tomomi Takano, Wataru Higuchi, Yasuhisa Iwao, Olga Singur, Ivan Reva, Yuta Otsuka, Toru Nakayashiki, Hirotada Mori, Galina Reva, Vladimir Kuznetsov, and Vladimir Potapov
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Medicine ,Science - Abstract
Two distinct classes of methicillin-resistant Staphylococcus aureus (MRSA) are spreading in hospitals (as hospital-acquired MRSA, HA-MRSA) and in the community (as community-acquired MRSA, CA-MRSA). Multilocus sequence type (ST) 239 MRSA, one of the most worldwide-disseminated lineages, has been noted as a representative HA-MRSA. Here, we isolated ST239 MRSA (spa type 3 [t037] and staphylococcal cassette chromosome mec [SCCmec] type III.1.1.1) and its novel variant with ST239/spa351 (t030)/SCCmecIII.1.1.4 (SCCmecIII(R)) not only from hospitals but also from patients with urethritis in the community in Russia. The Russian variant (strain 16K) possessed a hybrid genome consisting of CC8 and CC30, similar to the ST239/spa3/SCCmecIII.1.1.1 HA-MRSA (TW20) genome, but with marked diversity. The 16K' CC30 section had SCCmecIII(R) carrying the dcs-carrying unit (which corresponded to the SCCmecIVc J3 joining region of ST30 CA-MRSA), lacked SCCmercury, and possessed a novel mobile element structure (MES16K) carrying the ccrC-carrying unit (with the recombinase gene ccrC1 allele 3) and drug resistance tranposons. The Russian variant included strains with a high ability to transfer its multiple drug resistance by conjugation; e.g., for strain 16K, the transfer frequency of a chloramphenicol resistance plasmid (p16K-1 with 2.9 kb in size) reached 1.4×10(-2), followed by Tn554 conjugative transfer at 3.6×l0(-4). The Russian variant, which has been increasing recently, included divergent strains with different plasmid patterns and pulsed field gel electrophoresis profiles. The data demonstrate the alternative nature of ST239 MRSA as CA-MRSA and also as a drug resistance disseminator, and its micro but dynamic evolution in Russia.
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- 2012
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15. Four distances between pairs of amino acids provide a precise description of their interaction.
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Mati Cohen, Vladimir Potapov, and Gideon Schreiber
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Biology (General) ,QH301-705.5 - Abstract
The three-dimensional structures of proteins are stabilized by the interactions between amino acid residues. Here we report a method where four distances are calculated between any two side chains to provide an exact spatial definition of their bonds. The data were binned into a four-dimensional grid and compared to a random model, from which the preference for specific four-distances was calculated. A clear relation between the quality of the experimental data and the tightness of the distance distribution was observed, with crystal structure data providing far tighter distance distributions than NMR data. Since the four-distance data have higher information content than classical bond descriptions, we were able to identify many unique inter-residue features not found previously in proteins. For example, we found that the side chains of Arg, Glu, Val and Leu are not symmetrical in respect to the interactions of their head groups. The described method may be developed into a function, which computationally models accurately protein structures.
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- 2009
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16. Profiling DNA Ligase Substrate Specificity with a Pacific Biosciences Single‐Molecule Real‐Time Sequencing Assay
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Alexander T. Duckworth, Katharina Bilotti, Vladimir Potapov, and Gregory J. S. Lohman
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Medical Laboratory Technology ,General Immunology and Microbiology ,General Neuroscience ,Health Informatics ,General Pharmacology, Toxicology and Pharmaceutics ,General Biochemistry, Genetics and Molecular Biology - Published
- 2023
17. Programmable cleavage of linear double-stranded DNA by combined action of Argonaute CbAgo from Clostridium butyricum and nuclease deficient RecBC helicase from E. coli
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Rita Vaiskunaite, Jogirdas Vainauskas, Janna J L Morris, Vladimir Potapov, and Jurate Bitinaite
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Exodeoxyribonuclease V ,Bacterial Proteins ,Genetic Techniques ,Escherichia coli Proteins ,Argonaute Proteins ,Clostridium butyricum ,Genetics ,DNA Cleavage ,Endonucleases - Abstract
Prokaryotic Argonautes (pAgos) use small nucleic acids as specificity guides to cleave single-stranded DNA at complementary sequences. DNA targeting function of pAgos creates attractive opportunities for DNA manipulations that require programmable DNA cleavage. Currently, the use of mesophilic pAgos as programmable endonucleases is hampered by their limited action on double-stranded DNA (dsDNA). We demonstrate here that efficient cleavage of linear dsDNA by mesophilic Argonaute CbAgo from Clostridium butyricum can be activated in vitro via the DNA strand unwinding activity of nuclease deficient mutant of RecBC DNA helicase from Escherichia coli (referred to as RecBexo–C). Properties of CbAgo and characteristics of simultaneous cleavage of DNA strands in concurrence with DNA strand unwinding by RecBexo–C were thoroughly explored using 0.03–25 kb dsDNAs. When combined with RecBexo–C, CbAgo could cleave targets located 11–12.5 kb from the ends of linear dsDNA at 37°C. Our study demonstrates that CbAgo with RecBexo–C can be programmed to generate DNA fragments with custom-designed single-stranded overhangs suitable for ligation with compatible DNA fragments. The combination of CbAgo and RecBexo–C represents the most efficient mesophilic DNA-guided DNA-cleaving programmable endonuclease for in vitro use in diagnostic and synthetic biology methods that require sequence-specific nicking/cleavage of linear dsDNA at any desired location.
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- 2022
18. Detection and Quantitation of DNA Damage on a Genome‐wide Scale Using RADAR‐seq
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Kelly M, Zatopek, Vladimir, Potapov, Jennifer L, Ong, and Andrew F, Gardner
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Medical Laboratory Technology ,DNA Repair ,General Immunology and Microbiology ,Pyrimidine Dimers ,Genome, Archaeal ,General Neuroscience ,Escherichia coli ,Health Informatics ,Ribonucleotides ,General Pharmacology, Toxicology and Pharmaceutics ,General Biochemistry, Genetics and Molecular Biology ,DNA Damage - Abstract
The formation and persistence of DNA damage can impact biological processes such as DNA replication and transcription. To maintain genome stability and integrity, organisms rely on robust DNA damage repair pathways. Techniques to detect and locate DNA damage sites across a genome enable an understanding of the consequences of DNA damage as well as how damage is repaired, which can have key diagnostic and therapeutic implications. Importantly, advancements in technology have enabled the development of high-throughput sequencing-based DNA damage detection methods. These methods require DNA enrichment or amplification steps that limit the ability to quantitate the DNA damage sites. Further, each of these methods is typically tailored to detect only a specific type of damage. RAre DAmage and Repair (RADAR) sequencing is a DNA sequencing workflow that overcomes these limitations and enables detection and quantitation of DNA damage sites in any organism on a genome-wide scale. RADAR-seq works by replacing DNA damage sites with a patch of modified bases that can be directly detected by Pacific Biosciences Single-Molecule Real Time sequencing. Here, we present three protocols that enable detection of thymine dimers and ribonucleotides in bacterial and archaeal genomes. Basic Protocol 1 enables construction of a reference genome required for RADAR-seq analyses. Basic Protocol 2 describes how to locate, quantitate, and compare thymine dimer levels in Escherichia coli exposed to varying amounts of UV light. Basic Protocol 3 describes how to locate, quantitate, and compare ribonucleotide levels in wild-type and ΔRNaseH2 Thermococcus kodakarensis. Importantly, all three protocols provide in-depth steps for data analysis. Together they serve as proof-of-principle experiments that will allow users to adapt the protocols to locate and quantitate a wide variety of DNA damage sites in any organism. © 2022 New England Biolabs. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Constructing a reference genome utilizing SMRT sequencing Basic Protocol 2: Mapping and quantitating genomic thymine dimer formation in untreated versus UV-irradiated E. coli using RADAR-seq Basic Protocol 3: Mapping and quantitating genomic ribonucleotide incorporation in wildtype versus ΔRNaseH2 T. kodakarensis using RADAR-seq.
- Published
- 2022
19. DP-Colorings of Uniform Hypergraphs and Splittings of Boolean Hypercube into Faces
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Vladimir Potapov
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Computational Theory and Mathematics ,Applied Mathematics ,Discrete Mathematics and Combinatorics ,Geometry and Topology ,Theoretical Computer Science - Abstract
We develop a connection between DP-colorings of $k$-uniform hypergraphs of order $n$ and coverings of $n$-dimensional Boolean hypercube by pairs of antipodal $(n-k)$-dimensional faces. Bernshteyn and Kostochka established a lower bound on the number of edges in a non-2-DP-colorable $k$-uniform hypergraph namely, $2^{k-1}$ for odd $k$ and $2^{k-1}+1$ for even $k.$ They proved that these bounds are tight for $k=3,4$. In this paper, we prove that the bound is achieved for all odd $k\geq 3$.
- Published
- 2022
20. TM - polarization experimental electrical exploration from ice surface
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Arkadiy Zlobinskiy, Vladimir Mogilatov, and Vladimir Potapov
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Geophysics - Published
- 2023
21. N1-methyl-pseudouridine is incorporated with higher fidelity than pseudouridine in synthetic RNAs
- Author
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Tien-Hao Chen, Vladimir Potapov, Nan Dai, Jennifer L. Ong, and Bijoyita Roy
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Multidisciplinary - Abstract
In vitro transcribed synthetic messenger RNAs (mRNAs) represent a novel therapeutic modality. To overcome the inherent immunogenicity, as well as to increase the therapeutic efficacy of the molecules, uridine analogs—such as pseudouridine (Ψ) and N1-methyl-pseudouridine (m1Ψ), are incorporated in the synthetic mRNA. To decipher the fidelity with which these modifications are incorporated during the in vitro transcription (IVT) process, we compared the incorporation fidelity of uridine analogs with different RNA polymerases. We demonstrate that m1Ψ is incorporated with higher fidelity than Ψ. The fidelity of nucleotide incorporation differs between RNA polymerases; however, the spectrum of mutations observed between the RNAPs is similar. We also show that the array of nucleotide misincorporation is not dependent on the template DNA sequence context and that the distribution of these misincorporated nucleotides is not localized to any specific region along the length of the RNA. Based on our findings, we introduce a novel method to improve uridine analog incorporation fidelity during IVT. Our proof-of-concept experiments for higher-fidelity incorporation of uridine analogs during IVT provide guidelines when choosing RNAPs for the generation of modified uridine-containing mRNAs in vitro.
- Published
- 2022
22. Testing System Development for Full-Scale Simulators of Nuclear Power Plant Unit
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Alexey Lobarev, Denis Plotnikov, George Chukov, Vladimir Potapov, Alexander Nikulin, and Anatoly Kurilov
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- 2022
23. N
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Tien-Hao, Chen, Vladimir, Potapov, Nan, Dai, Jennifer L, Ong, and Bijoyita, Roy
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Base Sequence ,Nucleotides ,RNA, Messenger ,Uridine ,Pseudouridine - Abstract
In vitro transcribed synthetic messenger RNAs (mRNAs) represent a novel therapeutic modality. To overcome the inherent immunogenicity, as well as to increase the therapeutic efficacy of the molecules, uridine analogs-such as pseudouridine (Ψ) and N
- Published
- 2022
24. ORAL HOMEOSTASISSTATUSIN MILD CHRONIC GENERALIZED PERIODONTITIS AND MILD DENTAL PERI-IMPLANTITIS
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Vladimir Tlustenko, Oksana Gusyakova, Valentina Tlustenko, Dimitry Trunin, and Vladimir Potapov
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Cultural Studies ,History ,Literature and Literary Theory ,business.industry ,Medicine ,Dentistry ,business ,Generalized periodontitis ,Dental peri-implantitis - Abstract
The paper is focused on evaluating the oral cavity homeostasis in patients with mild chronic generalized periodontitis (CGP) (Group 1, 35 persons) and mild peri-implantitis (Group 2, 30 persons). The control group included healthy individuals (20 persons) with neither dental nor somatic issues. The material used for the study was oral fluid. The general metabolic processes in the periodontal and peri-implant area tissues were described based on analysis of the protein and mineral metabolism indicators, as well as on the hygiene and periodontal status indices. The paper presents the results of a comparative assessment involving Groups I and II with the control group and between Groups I and II. Our findings show changes in ion balance in both groups. Significant disturbances in the protein and mineral metabolism have been identified in the main groups, which contributes to the development of inflammation and reduced detoxification in periodontal and peri-implant tissues. A rise in Calcium and Magnesium indicates destructive processes in bone tissues. In case of mild CGP, these changes are more prominent. The oral hygiene and periodontal status indices in Group I proved to be significantly worse. Therefore, while performing implantation on the background of chronic generalized periodontitis, it is important to take into account its metabolic imbalance and implement preventive measures
- Published
- 2021
25. IMPROVED DIAGNOSISFOR ORAL MUCOSAL TUMORSIN THE DENTIST’S OFFICE
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Dimitry Trunin, Christina Ganina, Mikhail A. Postnikov, Valentina P. Kirillova, Vladimir Potapov, Artur Kerosirov, Alexey Gabrielyan, and Oleg I. Kaganov
- Subjects
Cultural Studies ,History ,Literature and Literary Theory ,business.industry ,Dentistry ,Medicine ,business - Abstract
Based on currently available literature, clinical examination remains the major method when handling cases of suspected malignancy. However, this method does not allow diagnosing cancer, due to which a large group of patients with possible oral mucosa cancer are referred to an oncologist. The search and use of affordable non-invasive methods for early diagnosis of oral mucosa tumors is an urgent issue facing the health system. The study involved analyzing 134 records of outpatients examined at the Samara Regional Oncological Clinic who were referred by dentists within 2014-2019 from the local polyclinic in Samara due to detection of tumors in oral mucosa and who underwent a biopsy. The patients were divided into two groups according to the examination methods. The inclusion criteria were: detection of various superficial oral mucosa neoplasms; referral from the dentist. The exclusion criteria were as follows: patients with submucosal oral cavity neoplasms referred to the oncologist by other medical specialists or self-referred patients. The control group included 63 patients who, after a conventional examination (including interview, examination, palpation), underwent an incisional biopsy followed by morphological examination at the oncologist’s office. In the major group, in 71 patients at their respective initial dental appointments a special examination algorithm was applied. This algorithm entailed an assessment of the identified risk factors. Indications for biopsy were identified using the histological verification index (HVI). Apart from the conventional examination methods (interview, examination, palpation), autofluorescence stomatoscopy was used, this being done for the purpose of differential diagnostics of inflammation, precancerous and malignant issues, depending on the glow type. In the main group, the initial stages of oral mucosa cancer were detected in 17 patients after biopsy; in the control group – in 4 patients (p=0.004). The developed algorithm used for scoring the patient’s clinical examination data combined with autofluorescence stomatoscopy allowed diagnosing accurately (90% of reliability) precancerous and cancerous diseases, as well as to use invasive research methods (biopsy) strictly following the indications. Aim of study: to improve diagnosis of oral mucosa neoplasms through improvement of the examination algorithm.
- Published
- 2021
26. Mismatch discrimination and sequence bias during end-joining by DNA ligases
- Author
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Katharina Bilotti, Vladimir Potapov, John M Pryor, Alexander T Duckworth, James L Keck, and Gregory J S Lohman
- Subjects
DNA Ligases ,Purines ,Genetics ,Humans ,DNA - Abstract
DNA ligases, critical enzymes for in vivo genome maintenance and modern molecular biology, catalyze the joining of adjacent 3′-OH and 5′-phosphorylated ends in DNA. To determine whether DNA annealing equilibria or properties intrinsic to the DNA ligase enzyme impact end-joining ligation outcomes, we used a highly multiplexed, sequencing-based assay to profile mismatch discrimination and sequence bias for several ligases capable of efficient end-joining. Our data reveal a spectrum of fidelity and bias, influenced by both the strength of overhang annealing as well as sequence preferences and mismatch tolerances that vary both in degree and kind between ligases. For example, while T7 DNA ligase shows a strong preference for ligating high GC sequences, other ligases show little GC-dependent bias, with human DNA Ligase 3 showing almost none. Similarly, mismatch tolerance varies widely among ligases, and while all ligases tested were most permissive of G:T mismatches, some ligases also tolerated bulkier purine:purine mismatches. These comprehensive fidelity and bias profiles provide insight into the biology of end-joining reactions and highlight the importance of ligase choice in application design.
- Published
- 2022
27. Microstructural Features of Welded Railway Frogs formed by Flash Butt Welding and Pulse-Arc Cladding
- Author
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Sergey Khlebnikov, Aelita Nikulina, Russian Federation Jsc \\'Novosibirsk Switch Plant\\', Zinaida Bataeva, Alexandra Porechina, and Vladimir Potapov
- Subjects
Cladding (metalworking) ,Materials science ,law ,Welding ,Composite material ,Flash welding ,law.invention - Published
- 2020
28. Click Chemistry of Selenium Dihalides: Novel Bicyclic Organoselenium Compounds Based on Selenenylation/Bis-Functionalization Reactions and Evaluation of Glutathione Peroxidase-like Activity
- Author
-
Maxim Musalov and Vladimir Potapov
- Subjects
Anions ,Glutathione Peroxidase ,Organic Chemistry ,General Medicine ,Catalysis ,Computer Science Applications ,Inorganic Chemistry ,Selenium ,Organoselenium Compounds ,Alkynes ,Click Chemistry ,Physical and Theoretical Chemistry ,Selenium Compounds ,Molecular Biology ,Spectroscopy ,selenium dihalides ,alcohols ,9-selenabicyclo[3.3.1]nonane derivatives ,glutathione peroxidase-like activity - Abstract
A number of highly efficient methods for the preparation of novel derivatives of 9-selenabicyclo[3.3.1]nonane in high yields based on selenium dibromide and cis,cis-1,5-cyclooctadiene are reported. The one-pot syntheses of 2,6-diorganyloxy-9-selenabicyclo[3.3.1]nonanes using various O-nucleophiles including alkanols, phenols, benzyl, allyl, and propargyl alcohols were developed. New 2,6-bis(1,2,3-triazol-1-yl)-9-selenabicyclo[3.3.1]nonanes were obtained by the copper-catalyzed 1,3-dipolar cycloaddition of 2,6-diazido-9-selenabicyclo[3.3.1]nonane with unsubstituted gaseous acetylene and propargyl alcohol. The synthesis of 2,6-bis(vinylsulfanyl)-9-selenabicyclo[3.3.1]nonane, based on the generation of corresponding dithiolate anion from bis[amino(iminio)methylsulfanyl]-9-selenabicyclo[3.3.1]nonane dibromide, followed by the nucleophilic addition of the dithiolate anion to unsubstituted acetylene, was developed. The glutathione peroxidase-like activity of the obtained water-soluble products was estimated and compounds with high activity were found. Overall, 2,6-Diazido-9-selenabicyclo[3.3.1]nonane exhibits the highest activity among the obtained compounds.
- Published
- 2022
29. SPACE: a suite of tools for protein structure prediction and analysis based on complementarity and environment.
- Author
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Vladimir Sobolev, Eran Eyal, Sergey Gerzon, Vladimir Potapov, Mariana Babor, Jaime Prilusky, and Marvin Edelman
- Published
- 2005
- Full Text
- View/download PDF
30. Embedding in MDS codes and Latin cubes
- Author
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Vladimir Potapov
- Subjects
05B15 ,FOS: Mathematics ,Discrete Mathematics and Combinatorics ,Mathematics - Combinatorics ,Combinatorics (math.CO) ,Data_CODINGANDINFORMATIONTHEORY ,Computer Science::Information Theory - Abstract
An embedding of a code is a mapping that preserves distances between codewords. We prove that any code with code distance $\rho$ and length $d$ can be embedded into an MDS code with the same code distance and length but under a larger alphabet. As a corollary we obtain embeddings of systems of partial mutually orthogonal Latin cubes and $n$-ary quasigroups., Comment: 7 pages
- Published
- 2021
31. Triple-Click Chemistry of Selenium Dihalides: Catalytic Regioselective and Highly Efficient Synthesis of Bis-1,2,3-Triazole Derivatives of 9-Selenabicyclo[3.3.1]nonane
- Author
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Maxim Musalov and Vladimir Potapov
- Subjects
acetylenes ,1,3-dipolar cycloaddition ,9-selenabicyclo[3.3.1]nonane derivatives ,copper-catalyzed reactions ,regioselective synthesis ,Physical and Theoretical Chemistry ,Catalysis ,General Environmental Science - Abstract
The catalytic regioselective and highly efficient synthesis of bis-1,2,3-triazole derivatives of 9-selenabicyclo[3.3.1]nonane was developed. The 1,3-dipolar cycloaddition reaction of 2,6-diazido-9-selenabicyclo[3.3.1]nonane with a variety of terminal acetylenes catalyzed by a copper acetate/sodium ascorbate system proceeded in a regioselective fashion, affording 2,6-bis(4-organyl-1,2,3-triazole)-9-selenabicyclo[3.3.1]nonanes in high yields (93–98%). The reaction of 2,6-diazido-9-selenabicyclo[3.3.1]nonane with dimethyl and diethyl acetylenedicarboxylates was carried out as thermal 1,3-dipolar Huisgen cycloaddition giving the corresponding 4,5-disubstituted 1,2,3-triazole derivatives of 9-selenabicyclo[3.3.1]nonane in high yields. The obtained products are potentially bioactive compounds and first representatives of selenium heterocycles combined with two 1,2,3-triazole moieties. 2.6-Diazido-9-selenabicyclo[3.3.1]nonane was obtained in quantitative yield via the reaction of sodium azide with 2,6-dibromo-9-selenabicyclo[3.3.1]nonane at room temperature. The latter compound was synthesized by stereoselective transannular addition of selenium dibromide to cis, cis-1,5-cyclooctadiene.
- Published
- 2022
32. Recent Advances in Design and Synthesis of Diselenafulvenes, Tetraselenafulvalenes, and Their Tellurium Analogs and Application for Materials Sciences
- Author
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Svetlana Amosova, Nataliya A. Makhaeva, and Vladimir Potapov
- Subjects
Chemistry (miscellaneous) ,Organic Chemistry ,Drug Discovery ,Molecular Medicine ,Pharmaceutical Science ,Physical and Theoretical Chemistry ,Analytical Chemistry - Abstract
The first organic metals were obtained based on tetrathiafulvalene. The most significant advance in the field of organic metals was the discovery of superconductivity. The first organic superconductors were obtained based on tetramethyltetraselenafulvalene. These facts demonstrate great importance of tetraselenafulvalenes and their precursors, diselenafulvenes, for materials sciences. Derivatives of 1,4-diselenafulvene and 1,4,5,8-tetraselenafulvalene are useful building blocks for organic synthesis and donor units for the preparation of charge-transfer complexes and radical ion salts, the construction of organic metals, superconductors, organic Dirac materials, semiconductors, ferromagnets, and other conductive materials. This review covers the literature on the design, synthesis, and application of 1,4,5,8-tetraselenafulvalenes and 1,4-diselenafulvenes and their tellurium analogs over the past 15–20 years. These two classes of compounds are interconnected, since the main part of methods for the synthesis of tetraselenafulvalenes is based on the diselenafulvene derivatives as starting compounds. Special attention is paid to the development of novel efficient synthetic approaches to these classes of compounds. Conducting properties and distinguishing features of materials based on tetraselenafulvalenes and their tellurium analogs as well as examples of materials with high conductivity are discussed.
- Published
- 2022
33. DEEP STRUCTURE OF SOUTH-EASTERN PART OF THE WEST SIBIRIAN PLATE AND IN THE SALAIR ACCORDING TO MAGNETOTELLURIC SOUNDINGS
- Author
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Vladimir Potapov and Elena Pospeeva
- Subjects
Paleontology ,Magnetotellurics ,South eastern ,Geology - Abstract
The first results of magnetotelluric studies carried out on the profile of v. Talmenka – Leninsk-Kuznetsky (South-Eastern part of the West Siberian plate and Salair) are considered, the main features of the distribution of deep electrical conductivity in the two main geological structures of the study area: the South-Eastern part of the West Siberian plate and the Salair zone are shown.
- Published
- 2019
34. РЕГИО- И СТЕРЕОСЕЛЕКТИВНЫЙ СИНТЕЗ ФУНКЦИОНАЛЬНЫХ ВИНИЛСУЛЬФИДОВ НА ОСНОВЕ ПИРИДИН-2-ТИОЛА, ПРОПИОЛОВОЙ КИСЛОТЫ И ЕЕ ПРОИЗВОДНЫХ
- Author
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Vladimir Potapov
- Published
- 2018
35. A bi-specific lectin from the mushroom Boletopsis grisea and its application in glycoanalytical workflows
- Author
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Vladimir Potapov, Christopher H. Taron, Saulius Vainauskas, Colleen McClung, Cristian I. Ruse, Jennifer L. Ong, Mehul B. Ganatra, and Anthony Z Francis
- Subjects
Proteomics ,0301 basic medicine ,Glycan ,Glycosylation ,Science ,Mutant ,Article ,Fungal Proteins ,Glycomics ,Fungal biology ,03 medical and health sciences ,Polysaccharides ,Lectins ,Humans ,Amino Acid Sequence ,Peptide sequence ,Boletopsis grisea ,Binding Sites ,Multidisciplinary ,030102 biochemistry & molecular biology ,biology ,Chemistry ,Basidiomycota ,Lectin ,carbohydrates (lipids) ,030104 developmental biology ,Biochemistry ,Fungal fruit body lectin family ,biology.protein ,Medicine ,Boletopsis leucomelaena ,Agaricales ,Sequence Alignment ,Protein Binding - Abstract
The BLL lectin from the edible Japanese “Kurokawa” mushroom (Boletopsis leucomelaena) was previously reported to bind to N-glycans harboring terminal N-acetylglucosamine (GlcNAc) and to induce apoptosis in a leukemia cell line. However, its gene has not been reported. In this study, we used a transcriptomics-based workflow to identify a full-length transcript of a BLL functional ortholog (termed BGL) from Boletopsis grisea, a close North American relative of B. leucomelaena. The deduced amino acid sequence of BGL was an obvious member of fungal fruit body lectin family (Pfam PF07367), a highly conserved group of mushroom lectins with a preference for binding O-glycans harboring the Thomsen–Friedenreich antigen (TF-antigen; Galβ1,3GalNAc-α-) and having two ligand binding sites. Functional characterization of recombinant BGL using glycan microarray analysis and surface plasmon resonance confirmed its ability to bind both the TF-antigen and β-GlcNAc-terminated N-glycans. Structure-guided mutagenesis of BGL’s two ligand binding clefts showed that one site is responsible for binding TF-antigen structures associated with O-glycans, whereas the second site specifically recognizes N-glycans with terminal β-GlcNAc. Additionally, the two sites show no evidence of allosteric communication. Finally, mutant BGL proteins having single functional bindings site were used to enrich GlcNAc-capped N-glycans or mucin type O-glycopeptides from complex samples in glycomics and glycoproteomics analytical workflows.
- Published
- 2021
36. Lithosphere of the West Transbaikalian Sector of the Central Asian Fold Belt According to Electromagnetic Studies
- Author
-
Vladimir Potapov, Elena Pospeeva, Ludmila Sokolova, and Albert Duchkov
- Subjects
Tectonics ,geography ,Rift ,geography.geographical_feature_category ,Lithosphere ,Magnetotellurics ,Geochemistry ,Fold (geology) ,Rift zone ,Geothermal gradient ,Mountain range ,Geology - Abstract
This paper presents the results of magnetotelluric (MT) studies performed within the Western Transbaikalia segment of the Central Asian fold belt along the Selenga River delta-Krasnyi Chikoi Village profile. The data are interpreted using the results of recent geological, petrological, geothermal, tectonic, and geochronological studies of the Mongolia-Transbaikalian part of the Central Asian fold belt, including large heterochronous provinces and zones. The studies have shown that the investigated area has a complex geologic and tectonic structure produced by extensive rifting leading to the formation of large crustal blocks and by intense magmatic fluid activity along deep fault zones. The investigated by a combination of blocks with different types of geoelectric section – mountain range and intermontane basins separated by long-lived deep fault zones. Significantly less tectonic activity of the West Transbaikalian rift zone, compared with the Baikal region of modern rift formation, was reflected in the contrast of the resistivity distribution and heat flow values in the North-Western and South-Eastern parts of the studied profile.
- Published
- 2021
37. Rapid 40 kb genome construction from 52 parts
- Author
-
Nilisha Pokhrel, Vladimir Potapov, Gregory J. S. Lohman, and John M. Pryor
- Subjects
chemistry.chemical_compound ,T7 bacteriophage ,chemistry ,Computer science ,Golden gate ,Human artificial chromosome ,Computational biology ,Genome ,DNA - Abstract
Large DNA constructs (>10 kb), including small genomes and artificial chromosomes, are invaluable tools for genetic engineering and vaccine development. However, the manufacture of these constructs is laborious. To address this problem, we applied new design insights and modified protocols to Golden Gate assembly. While this methodology is routinely used to assemble 5-10 DNA parts in one-step, we found that optimized assembly permitted >50 DNA fragments to be faithfully assembled in a single reaction. We applied these insights to genome construction, carrying out rapid assembly of the 40 kb T7 bacteriophage genome from 52 parts and recovering infectious phage particles after cellular transformation. The new Golden Gate assembly protocols and design principles described here can be applied to rapidly engineer a wide variety of large and complex assembly targets.
- Published
- 2020
38. Use of occlusal digital splint for treating the patients with temporomandibular joint dysfunction and planning orthopedic treatment
- Author
-
Rustem R. Gabdrafikov, Vladimir Potapov, Mukatdes Sadykov, Aleksandr Nesterov, Mikhail A. Postnikov, Natalya V. Pankratova, and Dmitry A. Trunin
- Subjects
musculoskeletal diseases ,medicine.medical_specialty ,Medicine (General) ,medicine.medical_treatment ,03 medical and health sciences ,0302 clinical medicine ,R5-920 ,stomatognathic system ,occlusal splint ,medicine ,030212 general & internal medicine ,030203 arthritis & rheumatology ,Orthodontics ,dentistry ,business.industry ,temporomandibular joint dysfunction ,General Medicine ,Temporomandibular joint ,stomatognathic diseases ,medicine.anatomical_structure ,orthopedic treatment ,Orthopedic surgery ,splint therapy ,Splint (medicine) ,business ,orthodontics - Abstract
Objective of the study: to develop and assess the occlusal digital splint for treating patients with temporomandibular joint dysfunction (TMJD). Material and Methods — 17 patients between the ages of 30 and 49 diagnosed with TMJD were admitted for treatment. To normalize mandibular position, an occlusal digital splint for all patients was manufactured in accordance with our original method. An intensity of pain sensations in all patients prior to, and after, the treatment was assessed by a visual analogue scale, along with the changes in the mandibular movements’ amplitude, and the signs of splint wear and stability of occlusal contacts. Results — Patients have adapted themselves well to the splint and found it convenient in use. The study results showed that it was sufficiently effective in treatment of TMJD. Reduction in pain intensity and restoration of mandibular movements’ amplitude were detected with certainty. Only in 2 (11.7%) cases, the signs of wear on the splint were found, as evidenced by the changes in pre-treatment occlusal contacts. In all other cases throughout the study, a stable occlusal contact has been encountered. Conclusion — Our results indicated that proposed occlusal digital splint may be considered as a treatment option for the patients with TMJ disorders.
- Published
- 2020
39. Math modeling of particle movements in a friction separator
- Author
-
Ekaterina Franyuk, Vladimir Potapov, Anatoliy Afanasyev, Sergei Frolov, and Valentin Potapov
- Subjects
010302 applied physics ,lcsh:GE1-350 ,0205 materials engineering ,020502 materials ,0103 physical sciences ,Separator (oil production) ,02 engineering and technology ,Mechanics ,01 natural sciences ,lcsh:Environmental sciences ,Mathematics - Abstract
A mathematical model of particles movement of separated material in a friction separator is proposed. It includes equations of their movement at each stage of separation (along a rough inclined plane, on a curvilinear part of a springboard, impact of a particle on the surface of a drum, free motion before leaving the separation zone), and differential equations of particle movement in circulating air flow created by a rotating drum; Each of these phases of motion is described by a system of equations obtained on the basis of basic laws of mechanics. An analysis of a particle motion along aslope plane was carried out on the basis of the law on energy changes. Depending on the ratios of the recovery factor and instantaneous friction, being random variables and also the coordinates of a point impact the particle is possible to move along different trajectories with different initial conditions. The mathematical model of the process of separation of loose multicomponent materials on a friction drum-shelf separator makes it possible to investigate comprehensively the process of separation of particles on friction and elastic properties and to optimize the operating modes of the apparatus at relatively low costs without using macaques and prototypes and investigate them experimentally. On the basis of analysis of the proposed theories of particles motion, the main ways are formulated of further improvement of methodology for designing and creating friction devices.
- Published
- 2020
40. Enabling one-pot Golden Gate assemblies of unprecedented complexity using data-optimized assembly design
- Author
-
Gregory J. S. Lohman, Eric J. Cantor, Katharina Bilotti, Vladimir Potapov, Rebecca Kucera, and John M. Pryor
- Subjects
0106 biological sciences ,0301 basic medicine ,Molecular biology ,Computer science ,DNA cloning ,Artificial Gene Amplification and Extension ,Biochemistry ,Polymerase Chain Reaction ,01 natural sciences ,law.invention ,Ligases ,Synthetic biology ,chemistry.chemical_compound ,law ,A-DNA ,Ligation Assay ,Polymerase chain reaction ,chemistry.chemical_classification ,Multidisciplinary ,Nucleotides ,DNA Restriction Enzymes ,Enzymes ,Recombinant DNA ,Engineering and Technology ,Medicine ,Synthetic Biology ,Research Article ,DNA Ligases ,Science ,Computational biology ,DNA construction ,Molecular cloning ,DNA sequencing ,03 medical and health sciences ,Cloning ,Molecular Biology Assays and Analysis Techniques ,DNA ligase ,business.industry ,DNA manipulations ,DNA fragment ligation ,Biology and Life Sciences ,Proteins ,DNA ,Modular design ,Research and analysis methods ,Restriction enzyme ,Molecular biology techniques ,030104 developmental biology ,Enzyme ,chemistry ,Enzymology ,business ,010606 plant biology & botany - Abstract
DNA assembly is an integral part of modern synthetic biology, as intricate genetic engineering projects require robust molecular cloning workflows. Golden Gate assembly is a frequently employed DNA assembly methodology that utilizes a Type IIS restriction enzyme and a DNA ligase to generate recombinant DNA constructs from smaller DNA fragments. However, the utility of this methodology has been limited by a lack of resources to guide experimental design. For example, selection of the DNA sequences at fusion sites between fragments is based on broad assembly guidelines or pre-vetted sets of junctions, rather than being customized for a particular application or cloning project. To facilitate the design of robust assembly reactions, we developed a high-throughput DNA sequencing assay to examine reaction outcomes of Golden Gate assembly with T4 DNA ligase and the most commonly used Type IIS restriction enzymes that generate three-base and four-base overhangs. Next, we incorporated these findings into a suite of webtools that design assembly reactions using the experimental data. These webtools can be used to create customized assemblies from a target DNA sequence or a desired number of fragments. Lastly, we demonstrate how using these tools expands the limits of current assembly systems by carrying out one-pot assemblies of up to 35 DNA fragments. Full implementation of the tools developed here enables direct expansion of existing assembly standards for modular cloning systems (e.g. MoClo) as well as the formation of robust new high-fidelity standards.
- Published
- 2020
41. STUDY OF INFLUENCE OF FREEZING-DEFROSTING ON THERMOPHYSICAL PROPERTIES OF MEAT SYSTEMS
- Author
-
Tetiana Zhelieva, Olga Grinchenko, Marina Yancheva, Olena Dromenko, and Vladimir Potapov
- Subjects
Aggregate (composite) ,Moisture ,Chemistry ,0402 animal and dairy science ,Meat Proteins ,food and beverages ,04 agricultural and veterinary sciences ,Raw material ,040401 food science ,040201 dairy & animal science ,Fat mass ,0404 agricultural biotechnology ,Defrosting ,Phase (matter) ,Food science ,Chemical composition - Abstract
There were studied thermophysical properties of meat systems, based on comminuted beef with different chemical compositions in the process of freezing-defrosting. It was demonstrated, that the morphological base of meat (the ratio of muscular, connective and fatty tissues) and its chemical composition essentially influence thermophysical properties in the process of freezing-defrosting. It was revealed, that under conditions of realization of freezing-defrosting cycle with the fat mass share increase, the temperature increase of the maximal speed of crystal creation, decrease of the cryoscopic temperature interval, increase of the share of moisture that changes its aggregate state in the cryoscopic temperature interval, increase of specific heat of the phase transfer in the cryoscopic temperature interval are observed in a meat system. The type of changes of the cryoscopic temperature interval allows to detect that fat essentially influences the process of freezing-defrosting. The realized studies of comparison of thermodynamic changes in meat systems at refrigerator processing allowed to determine the strategy of saving meat systems’ stability that is in providing meat proteins’ colloid stability and renewing initial properties of the meat raw material after storage and defrosting.
- Published
- 2018
42. APPLYING METHODS OF PHOTOGRAMMETRY TO DIAGNOSE DISEAS OF TEMPOROMANDIBULAR JOINT
- Author
-
Lyudmila Kameneva, Vladimir Potapov, Stanislav Konov, and Elena Pyatanova
- Subjects
Orthodontics ,medicine.anatomical_structure ,Photogrammetry ,Computer science ,Movement (music) ,Median Line ,Technical university ,Mandible ,medicine ,Sagittal plane ,Chin ,Temporomandibular joint - Abstract
Subject. The increasing need for searching of new methods of diagnosis of diseases of a temporal and mandibular joint, is caused by high extent of distribution. The leading experts studying pathology ви - a juicy and mandibular joint, recognize need of studying of driving of a mandible. Purpose. Studying of graphic record of movements of a mandible. Methodology. We carried out registration of the movements of the lower jaw in three mutually perpendicular planes at 122 surveyed aged from 18 up to 25 years, 100 women and 22 men. Within collateral research work of SAMGMU and MSTU (The Moscow State technical university), on the basis of MSTU of «STANKIN» the project on creation of system of registration of the movement of a mandible for diagnosis of diseases ви - a juicy and mandibular joint was realized. The device has two webcams which record and write down the movements of a mandible, by means of keeping track of by the marker attached on the most acting chin point. Results At registration of the movements of a mandible we analyzed the period during 5 serial acts of an unclosing of a mouth. The program transformed the obtained data to schedules (Fig. 4-A, B, C of the application) on which vertical and sagittal deflections during research time are displayed. The possibility of system with a high precision to reflect trajectories of movements and to define at what moment of an unclosing or shutting of a mouth occurs the moment of «failure» — a sharp deviation from the median line. Conclusions. The advantage of the offered method is realization of non-contact technology of registration of the movements of a mandible. In difference from the analog systems of registration of the movements we apply only a measuring marker on a chin which does not obstruct natural traffic of a mandible and does not allow the doctor to influence reliability of received information.
- Published
- 2017
43. ПРИМЕР ЛЕГКОГО ЗАМЕЩЕНИЯ ГИДРОКСИГРУППЫ ЗА СЧЕТ ЭФФЕКТА АНХИМЕРНОГО СОДЕЙСТВИЯ АТОМА СЕЛЕНА
- Author
-
Vladimir Potapov
- Published
- 2018
44. The clinical-anatomical evaluation and modeling of the normal and pathological temporomandibular joint, based on the hardware and software complex «Luch-S»
- Author
-
Vladimir Potapov, B. I. Yaremin, Arina Mal'tseva, Aleksey Mironov, Valentina Ivanova, A. V. Kolsanov, Ol'ga Zheltyakova, and Renat Yunusov
- Subjects
Orthodontics ,Pathology ,medicine.medical_specialty ,Software ,medicine.anatomical_structure ,business.industry ,Computer science ,medicine ,business ,Pathological ,Temporomandibular joint - Published
- 2016
45. RADAR-seq: A RAre DAmage and Repair sequencing method for detecting DNA damage on a genome-wide scale
- Author
-
Lisa L. Maduzia, Kelly M Zatopek, Jennifer L. Ong, Lixin Chen, Vladimir Potapov, Thomas C. Evans, Ece Alpaslan, Andrew F. Gardner, and Laurence Ettwiller
- Subjects
DNA Replication ,DNA, Bacterial ,DNA Repair ,DNA repair ,DNA damage ,Ultraviolet Rays ,Computational biology ,Biology ,Origin of replication ,Biochemistry ,DNA sequencing ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Genome, Archaeal ,Escherichia coli ,Molecular Biology ,030304 developmental biology ,0303 health sciences ,Mutagenicity Tests ,DNA replication ,High-Throughput Nucleotide Sequencing ,Cell Biology ,Sequence Analysis, DNA ,Ribonucleotides ,Thermococcus ,DNA, Archaeal ,chemistry ,Replication Initiation ,Pyrimidine Dimers ,030220 oncology & carcinogenesis ,DNA ,Genome, Bacterial ,Single molecule real time sequencing ,DNA Damage - Abstract
RAre DAmage and Repair sequencing (RADAR-seq) is a highly adaptable sequencing method that enables the identification and detection of rare DNA damage events for a wide variety of DNA lesions at single-molecule resolution on a genome-wide scale. In RADAR-seq, DNA lesions are replaced with a patch of modified bases that can be directly detected by Pacific Biosciences Single Molecule Real-Time (SMRT) sequencing. RADAR-seq enables dynamic detection over a wide range of DNA damage frequencies, including low physiological levels. Furthermore, without the need for DNA amplification and enrichment steps, RADAR-seq provides sequencing coverage of damaged and undamaged DNA across an entire genome. Here, we use RADAR-seq to measure the frequency and map the location of ribonucleotides in wild-type and RNaseH2-deficient E. coli and Thermococcus kodakarensis strains. Additionally, by tracking ribonucleotides incorporated during in vivo lagging strand DNA synthesis, we determined the replication initiation point in E. coli, and its relation to the origin of replication (oriC). RADAR-seq was also used to map cyclobutane pyrimidine dimers (CPDs) in Escherichia coli (E. coli) genomic DNA exposed to UV-radiation. On a broader scale, RADAR-seq can be applied to understand formation and repair of DNA damage, the correlation between DNA damage and disease initiation and progression, and complex biological pathways, including DNA replication.
- Published
- 2019
46. Therminator DNA Polymerase: Modified Nucleotides and Unnatural Substrates
- Author
-
William E. Jack, Madeleine M. Boyle, Jackson Buss, Alexandra M. Gehring, Vladimir Potapov, Andrew F. Gardner, Kelly M Zatopek, Jennifer L. Ong, Kiserian M. Jackson, and Ivan R. Corrêa
- Subjects
0301 basic medicine ,DNA polymerase ,Aptamer ,aptamers ,Review ,Computational biology ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,Biochemistry ,functionalized DNA ,DNA sequencing ,03 medical and health sciences ,Synthetic biology ,xenonucleic acids ,0302 clinical medicine ,Molecular Biosciences ,Nucleotide ,lcsh:QH301-705.5 ,Molecular Biology ,chemistry.chemical_classification ,unnatural base pairs ,biology ,030104 developmental biology ,lcsh:Biology (General) ,chemistry ,030220 oncology & carcinogenesis ,GenBank ,biology.protein - Abstract
A variant of 9°N DNA polymerase [Genbank ID (AAA88769.1)] with three mutations (D141A, E143A, A485L) and commercialized under the name “Therminator DNA polymerase” has the ability to incorporate a variety of modified nucleotide classes. This Review focuses on how Therminator DNA Polymerase has enabled new technologies in synthetic biology and DNA sequencing. In addition, we discuss mechanisms for increased modified nucleotide incorporation.
- Published
- 2019
47. Protein structure modelling and evaluation based on a 4-distance description of side-chain interactions.
- Author
-
Vladimir Potapov, Mati Cohen, Yuval Inbar, and Gideon Schreiber
- Published
- 2010
- Full Text
- View/download PDF
48. Biochemical reconstitution and genetic characterization of the major oxidative damage base excision DNA repair pathway in Thermococcus kodakarensis
- Author
-
Andrew F. Gardner, Thomas J. Santangelo, Vladimir Potapov, Brett W. Burkhart, Kelly M Zatopek, and Alexandra M. Gehring
- Subjects
Guanine ,DNA Repair ,DNA repair ,Archaeal Proteins ,DNA polymerase ,Biochemistry ,Article ,DNA Glycosylases ,AP endonuclease ,03 medical and health sciences ,Endonuclease ,0302 clinical medicine ,Nucleic acid enzymology ,Genetics ,AP site ,Molecular Biology ,030304 developmental biology ,0303 health sciences ,biology ,DNA glycosylase ,Cell Biology ,DNA Repair Pathway ,Base excision repair ,biology.organism_classification ,Archaea ,Thermococcus kodakarensis ,Base excision repair (BER) ,Thermococcus ,Oxidative Stress ,030220 oncology & carcinogenesis ,biology.protein ,8oxo-guanine (8-oxoG) ,DNA Damage - Abstract
Reactive oxygen species drive the oxidation of guanine to 8-oxoguanine (8oxoG), which threatens genome integrity. The repair of 8oxoG is carried out by base excision repair enzymes in Bacteria and Eukarya, however, little is known about archaeal 8oxoG repair. This study identifies a member of the Ogg-subfamily archaeal GO glycosylase (AGOG) in Thermococcus kodakarensis, an anaerobic, hyperthermophilic archaeon, and delineates its mechanism, kinetics, and substrate specificity. TkoAGOG is the major 8oxoG glycosylase in T. kodakarensis, but is non-essential. In addition to TkoAGOG, the major apurinic/apyrimidinic (AP) endonuclease (TkoEndoIV) required for archaeal base excision repair and cell viability was identified and characterized. Enzymes required for the archaeal oxidative damage base excision repair pathway were identified and the complete pathway was reconstituted. This study illustrates the conservation of oxidative damage repair across all Domains of life.
- Published
- 2020
49. Comprehensive Profiling of Four Base Overhang Ligation Fidelity by T4 DNA Ligase and Application to DNA Assembly
- Author
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Thomas C. Evans, Bradley W. Langhorst, Barry Canton, Rebecca Kucera, Thomas F. Knight, Vladimir Potapov, Jennifer L. Ong, Katharina Bilotti, John M. Pryor, Eric J. Cantor, and Gregory J. S. Lohman
- Subjects
0301 basic medicine ,DNA Ligases ,Computer science ,media_common.quotation_subject ,genetic processes ,Biomedical Engineering ,Fidelity ,Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid ,Computational biology ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,03 medical and health sciences ,chemistry.chemical_compound ,Synthetic biology ,0302 clinical medicine ,Dna assembly ,Golden gate ,Base Pairing ,media_common ,chemistry.chemical_classification ,DNA ligase ,General Medicine ,DNA ,030104 developmental biology ,chemistry ,Lac Operon ,Synthetic Biology ,Ligation ,030217 neurology & neurosurgery - Abstract
Synthetic biology relies on the manufacture of large and complex DNA constructs from libraries of genetic parts. Golden Gate and other Type IIS restriction enzyme-dependent DNA assembly methods enable rapid construction of genes and operons through one-pot, multifragment assembly, with the ordering of parts determined by the ligation of Watson-Crick base-paired overhangs. However, ligation of mismatched overhangs leads to erroneous assembly, and low-efficiency Watson Crick pairings can lead to truncated assemblies. Using sets of empirically vetted, high-accuracy junction pairs avoids this issue but limits the number of parts that can be joined in a single reaction. Here, we report the use of comprehensive end-joining ligation fidelity and bias data to predict high accuracy junction sets for Golden Gate assembly. The ligation profile accurately predicted junction fidelity in ten-fragment Golden Gate assembly reactions and enabled accurate and efficient assembly of a lac cassette from up to 24-fragments in a single reaction.
- Published
- 2018
50. Optimization of Golden Gate assembly through application of ligation sequence-dependent fidelity and bias profiling
- Author
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Jennifer L. Ong, Thomas F. Knight, Lohman Gjs, Rebecca Kucera, Katharina Bilotti, Thomas C. Evans, John M. Pryor, Bradley W. Langhorst, Eric J. Cantor, Barry Canton, and Vladimir Potapov
- Subjects
Synthetic biology ,chemistry.chemical_compound ,Sequence dependent ,chemistry ,Computer science ,media_common.quotation_subject ,Fidelity ,Golden gate ,Computational biology ,Ligation ,Gene ,DNA ,media_common - Abstract
Modern synthetic biology depends on the manufacture of large DNA constructs from libraries of genes, regulatory elements or other genetic parts. Type IIS restriction enzyme-dependent DNA assembly methods (e.g., Golden Gate) enable rapid one-pot, ordered, multi-fragment DNA assembly, facilitating the generation of high-complexity constructs. The order of assembly of genetic parts is determined by the ligation of flanking Watson-Crick base-paired overhangs. The ligation of mismatched overhangs leads to erroneous assembly, and the need to avoid such pairings has typically been accomplished by using small sets of empirically vetted junction pairs, limiting the number of parts that can be joined in a single reaction. Here, we report the use of a comprehensive method for profiling end-joining ligation fidelity and bias to predict highly accurate sets of connections for ligation-based DNA assembly methods. This data set allows quantification of sequence-dependent ligation efficiency and identification of mismatch-prone pairings. The ligation profile accurately predicted junction fidelity in ten-fragment Golden Gate assembly reactions, and enabled efficient assembly of a lac cassette from up to 24-fragments in a single reaction. Application of the ligation fidelity profile to inform choice of junctions thus enables highly flexible assembly design, with >20 fragments in a single reaction.
- Published
- 2018
- Full Text
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