keyword
MENU ▼
Read by QxMD icon Read
search

Tetramer

keyword
https://www.readbyqxmd.com/read/28934509/yeast-caf-1-assembles-histone-h3-h4-2-tetramers-prior-to-dna-deposition
#1
Duane D Winkler, Hui Zhou, Mohd A Dar, Zhiguo Zhang, Karolin Luger
No abstract text is available yet for this article.
September 19, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/28934476/crystal-structure-of-an-engineered-hiv-specific-recombinase-for-removal-of-integrated-proviral-dna
#2
Gretchen Meinke, Janet Karpinski, Frank Buchholz, Andrew Bohm
As part of the HIV infection cycle, viral DNA inserts into the genome of host cells such that the integrated DNA encoding the viral proteins is flanked by long terminal repeat (LTR) regions from the retrovirus. In an effort to develop novel genome editing techniques that safely excise HIV provirus from cells, Tre, an engineered version of Cre recombinase, was designed to target a 34-bp sequence within the HIV-1 LTR (loxLTR). The sequence targeted by Tre lacks the symmetry present in loxP, the natural DNA substrate for Cre...
September 19, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/28933692/a-quantitative-hypermorphic-cngc-allele-confers-ectopic-calcium-flux-and-impairs-cellular-development
#3
David M Chiasson, Kristina Haage, Katharina Sollweck, Andreas Brachmann, Petra Dietrich, Martin Parniske
The coordinated control of Ca(2+) signaling is essential for development in eukaryotes. Cyclic nucleotide-gated channel (CNGC) family members mediate Ca(2+) influx from cellular stores in plants(1-4). Here we report the unusual genetic behavior of a quantitative gain-of-function CNGC mutation (brush) in Lotus japonicus resulting in a leaky tetrameric channel. brush resides in a cluster of redundant CNGCs encoding subunits which resemble metazoan voltage-gated potassium (Kv1-Kv4) channels in assembly and gating properties...
September 21, 2017: ELife
https://www.readbyqxmd.com/read/28931050/saxs-and-stability-studies-of-iron-induced-oligomers-of-bacterial-frataxin-cyay
#4
Mostafa Fekry, Wessen Alshokry, Przemysław Grela, Marek Tchórzewski, Eva-Christina Ahlgren, Christopher A Söderberg, Oleksandr Gakh, Grazia Isaya, Salam Al-Karadaghi
Frataxin is a highly conserved protein found in both prokaryotes and eukaryotes. It is involved in several central functions in cells, which include iron delivery to biochemical processes, such as heme synthesis, assembly of iron-sulfur clusters (ISC), storage of surplus iron in conditions of iron overload, and repair of ISC in aconitase. Frataxin from different organisms has been shown to undergo iron-dependent oligomerization. At least two different classes of oligomers, with different modes of oligomer packing and stabilization, have been identified...
2017: PloS One
https://www.readbyqxmd.com/read/28928411/reca-ssb-interaction-modulates-reca-nucleoprotein-filament-formation-on-ssb-wrapped-dna
#5
Hung-Yi Wu, Chih-Hao Lu, Hung-Wen Li
E. coli RecA recombinase catalyzes the homology pairing and strand exchange reactions in homologous recombinational repair. RecA must compete with single-stranded DNA binding proteins (SSB) for single-stranded DNA (ssDNA) substrates to form RecA nucleoprotein filaments, as the first step of this repair process. It has been suggested that RecA filaments assemble mainly by binding and extending onto the free ssDNA region not covered by SSB, or are assisted by mediators. Using the tethered particle motion (TPM) technique, we monitored individual RecA filament assembly on SSB-wrapped ssDNA in real-time...
September 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28925703/hydrolysis-of-dimethyl-methylphosphonate-by-the-cyclic-tetramer-of-zirconium-hydroxide
#6
Igor V Schweigert, Daniel Gunlycke
We present hybrid density functional theory (DFT) calculations of hydrolysis of dimethyl methylphosphonate (DMMP) by the cyclic tetramer of zirconium hydroxide [Zr4(OH)16]. Various binding configurations of DMMP and its hydrolysis products on the tetramer as well as transition structures connecting them were explored using structure optimizations based on multiple, randomly selected initial structures. We find that DMMP can bind to the tetramer through the phosphoryl O forming either a strong hydrogen bond to a bridging hydroxyl or a coordinate bond to a coordinatively unsaturated Zr atom...
September 19, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28925536/solution-structure-of-alme2f-and-its-reactivity-with-metallocenes-mimicking-cation-anion-interactions-in-metallocenium-mao-inner-sphere-ion-pairs
#7
Leone Oliva, Patrizia Oliva, Nunzia Galdi, Claudio Pellecchia, Leonardo Sian, Alceo Macchioni, Cristiano Zuccaccia
The solution structure of AlMe2F and its reactivity with a prototypical ansa-metallocene have been investigated by advanced NMR techniques, in an attempt to indirectly shed some light on the "structure and working principles" of methylalumoxane (MAO) mixtures in olefin polymerization. In solution, AlMe2F leads to a complex equilibrium of oligomeric species, including a heterocubane [(Me2Al)4F4] tetramer, resembling the behavior of MAO. Such a complex mixture reacts with the prototypical ansa-zirconocene (ETH)ZrMe2 affording [(ETH)ZrMeδ+(μ-F)(AlMe2F)nAlMe3δ-] inner-sphere ion pairs through the successive insertions/deinsertion of AlMe2F units into the Zr…(μ-F) bond...
September 19, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28924213/an-alternate-mode-of-oligomerization-for-e-coli-seca
#8
Aliakbar Khalili Yazdi, Grant C Vezina, Brian H Shilton
SecA is the ATPase of preprotein translocase. SecA is a dimer in solution and changes in its oligomeric state may function in preprotein translocation. The SecA-N68 construct, in which the C-terminal helical domains of SecA are deleted, was used to investigate the mechanism of SecA oligomerization. SecA-N68 is in equilibrium between monomers, dimers, and tetramers. Subunit interactions in the SecA-N68 tetramer are mediated entirely by unstructured regions at its N- and C-termini: when the termini are deleted to yield SecA-N68∆NC, the construct is completely monomeric...
September 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28922500/total-synthesis-of-the-diglycosidic-tetramic-acid-ancorinoside-a
#9
Markus Petermichl, Rainer Schobert
Ancorinoside A, a metabolite of a sponge Ancorina sp., was prepared in 18 steps as the first derivative of this class of glycosylated 3-acyltetramic acids. It features a β-D-glucopyranosyl-(1→4)-β-D-galacturonic acid linked to a D-aspartic acid derived tetramic acid via a 3-docosanoyl spacer. The diglycoside was built up by connecting the protected monosaccharides D-galactose and D-glucose via a thioglycoside glycosylation. Attachment of the spacer by a subsequent Schmidt glycosylation of this diglycoside, TEMPO oxidation to the uronic acid, functionalisation of the spacer terminus with an N-(β-ketoacyl)aspartate, and a final Dieckmann cyclisation of the latter were the key steps leading to ancorinoside A...
September 18, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28920981/oxygenation-of-rzn-n-o-type-complexes-as-an-efficient-route-to-zinc-alkoxides-not-accessible-via-the-classical-alcoholysis-path
#10
Zbigniew Wróbel, Tomasz Pietrzak, Iwona Justyniak, Janusz Lewiński
The controlled oxygenation of alkylzinc complexes supported by a 2-ester substituted pyrrolate ligand (L) leads to zinc alkoxides with an uncommon structural motif in the solid state: a trimer [(L)Zn(μ-O(t)Bu)]3 with the central [Zn3(μ-OR)3] ring and a tetramer [(L)Zn(μ3-OEt)]4 with a heterocubane-type structure. Strikingly, these seemingly simple zinc alkoxides are not accessible via the classical alcoholysis route.
September 18, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28920433/fluorotryptophan-incorporation-modulates-the-structure-and-stability-of-transthyretin-in-a-site-specific-manner
#11
Xun Sun, H Jane Dyson, Peter E Wright
Abnormal deposition of aggregated wild-type (WT) human transthyretin (TTR) and its pathogenic variants is responsible for cardiomyopathy and neuropathy related to TTR amyloidosis. The tryptophan (Trp) fluorescence measurements typically used to study structural changes of TTR do not yield site-specific information on the two Trp residues per TTR protomer. To obtain such information, tryptophan labeled with fluorine at the 5 and 6 positions (5FW and 6FW) was incorporated into TTR. Fluorescence of 5FW and 6FW-labeled WT-TTR (WT-5FW and WT-6FW) and a single-Trp mutant W41Y showed that the photophysics of incorporated fluoro-Trp is consistent with site-specific solvation of the indole ring of W41 and W79...
September 18, 2017: Biochemistry
https://www.readbyqxmd.com/read/28919785/biomarker-analysis-and-clinical-relevance-of-tk1-on-the-cell-membrane-of-burkitt-s-lymphoma-and-acute-lymphoblastic-leukemia
#12
Evita G Weagel, Wei Meng, Michelle H Townsend, Edwin J Velazquez, Rachel A Brog, Michael W Boyer, K Scott Weber, Richard A Robison, Kim L O'Neill
TK1 is an enzyme involved in DNA synthesis and repair. TK1 is usually found elevated in cancer patients' serum, which makes it a useful tumor proliferation biomarker that strongly correlates with cancer stage, metastatic capabilities, and recurrence risk. In this study, we show that TK1 is upregulated and localizes on the plasma membrane of Burkitt's lymphoma, acute promyelocytic leukemia, T cell leukemia, and acute lymphoblastic leukemia (ALL). Using flow cytometry, we confirmed that TK1 localizes on the surface of Raji, HL60, and Jurkat cell lines and on ALL clinical samples...
2017: OncoTargets and Therapy
https://www.readbyqxmd.com/read/28916749/checkpoint-blockade-immunotherapy-reshapes-the-high-dimensional-phenotypic-heterogeneity-of-murine-intratumoural-neoantigen-specific-cd8-t-cells
#13
M Fehlings, Y Simoni, H L Penny, E Becht, C Y Loh, M M Gubin, J P Ward, S C Wong, R D Schreiber, E W Newell
The analysis of neoantigen-specific CD8(+) T cells in tumour-bearing individuals is challenging due to the small pool of tumour antigen-specific T cells. Here we show that mass cytometry with multiplex combinatorial tetramer staining can identify and characterize neoantigen-specific CD8(+) T cells in mice bearing T3 methylcholanthrene-induced sarcomas that are susceptible to checkpoint blockade immunotherapy. Among 81 candidate antigens tested, we identify T cells restricted to two known neoantigens simultaneously in tumours, spleens and lymph nodes in tumour-bearing mice...
September 15, 2017: Nature Communications
https://www.readbyqxmd.com/read/28915239/structural-basis-for-the-high-specificity-of-a-trypanosoma-congolense-immunoassay-targeting-glycosomal-aldolase
#14
Joar Pinto, Steven Odongo, Felicity Lee, Vaiva Gaspariunaite, Serge Muyldermans, Stefan Magez, Yann G-J Sterckx
BACKGROUND: Animal African trypanosomosis (AAT) is a neglected tropical disease which imposes a heavy burden on the livestock industry in Sub-Saharan Africa. Its causative agents are Trypanosoma parasites, with T. congolense and T. vivax being responsible for the majority of the cases. Recently, we identified a Nanobody (Nb474) that was employed to develop a homologous sandwich ELISA targeting T. congolense fructose-1,6-bisphosphate aldolase (TcoALD). Despite the high sequence identity between trypanosomatid aldolases, the Nb474-based immunoassay is highly specific for T...
September 15, 2017: PLoS Neglected Tropical Diseases
https://www.readbyqxmd.com/read/28912775/shared-and-distinct-phenotypes-and-functions-of-human-cd161-v%C3%AE-7-2-t-cell-subsets
#15
Ayako Kurioka, Aminu S Jahun, Rachel F Hannaway, Lucy J Walker, Joannah R Fergusson, Eva Sverremark-Ekström, Alexandra J Corbett, James E Ussher, Christian B Willberg, Paul Klenerman
Human mucosal-associated invariant T (MAIT) cells are an important T cell subset that are enriched in tissues and possess potent effector functions. Typically such cells are marked by their expression of Vα7.2-Jα33/Jα20/Jα12 T cell receptors, and functionally they are major histocompatibility complex class I-related protein 1 (MR1)-restricted, responding to bacterially derived riboflavin synthesis intermediates. MAIT cells are contained within the CD161++ Vα7.2+ T cell population, the majority of which express the CD8 receptor (CD8+), while a smaller fraction expresses neither CD8 or CD4 coreceptor (double negative; DN) and a further minority are CD4+...
2017: Frontiers in Immunology
https://www.readbyqxmd.com/read/28911633/an-analysis-method-for-flavan-3-ols-using-high-performance-liquid-chromatography-coupled-with-a-fluorescence-detector
#16
Liuqing Wang, Yoko Yamashita, Akiko Saito, Hitoshi Ashida
Procyanidins belong to a family of flavan-3-ols, which consist of monomers, (+)-catechin and (-)-epicatechin, and their oligomers and polymers, and are distributed in many plant-derived foods. Procyanidins are reported to have many beneficial physiological activities, such as antihypertensive and anticancer effects. However, the bioavailability of procyanidins is not well understood owing to a lack of convenient and high-sensitive analysis methods. The aim of this study was to develop an improved method for determining procyanidin content in both food materials and biological samples...
July 2017: Journal of Food and Drug Analysis
https://www.readbyqxmd.com/read/28911198/loss-of-native-%C3%AE-synuclein-multimerization-by-strategically-mutating-its-amphipathic-helix-causes-abnormal-vesicle-interactions-in-neuronal-cells
#17
Ulf Dettmer, Nagendran Ramalingam, Victoria E von Saucken, Tae-Eun Kim, Andrew J Newman, Elizabeth Terry-Kantor, Silke Nuber, Maria Ericsson, Saranna Fanning, Tim Bartels, Susan Lindquist, Oren A Levy, Dennis Selkoe
α-Synuclein (αS) forms round cytoplasmic inclusions in Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Evidence suggests a physiological function of αS in vesicle trafficking and release. In contrast to earlier tenets, recent work indicates that αS normally exists in cells in a dynamic equilibrium between monomers and tetramers/multimers. We engineered αS mutants incapable of multimerization, leading to excess monomers at vesicle membranes. By EM, such mutants induced prominent vesicle clustering, leading to round cytoplasmic inclusions...
September 15, 2017: Human Molecular Genetics
https://www.readbyqxmd.com/read/28911118/multimerization-rules-for-g-quadruplexes
#18
Sofia Kolesnikova, Martin Hubálek, Lucie Bednárová, Josef Cvacka, Edward A Curtis
G-quadruplexes can multimerize under certain conditions, but the sequence requirements of such structures are not well understood. In this study, we investigated the ability of all possible variants of the central tetrad in a monomeric, parallel-strand G-quadruplex to form higher-order structures. Although most of these 256 variants existed primarily as monomers under the conditions of our screen, ∼10% formed dimers or tetramers. These structures could form in a wide range of monovalent and divalent metal ions, and folding was highly cooperative in both KCl and MgCl2...
September 6, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/28910535/emergence-of-a-new-self-replicator-from-a-dynamic-combinatorial-library-requires-a-specific-pre-existing-replicator
#19
Yigit Altay, Meniz Tezcan, Sijbren Otto
Our knowledge regarding the early steps in the formation of evolvable life and what constitutes the minimal molecular basis of life remains far from complete. The recent emergence of systems chemistry reinvigorated the investigation of systems of self-replicating molecules to address these questions. Most of these studies focus on single replicators and the effects of replicators on the emergence of other replicators remains under-investigated. Here we show the cross-catalyzed emergence of a novel self-replicator from a dynamic combinatorial library made from a threonine containing peptide building block, which, by itself, only forms trimers and tetramers that do not replicate...
September 14, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28905328/lessons-learned-from-protein-aggregation-toward-technological-and-biomedical-applications
#20
REVIEW
César L Avila, Silvina Chaves, Sergio B Socias, Esteban Vera-Pingitore, Florencia González-Lizárraga, Cecilia Vera, Diego Ploper, Rosana Chehín
The close relationship between protein aggregation and neurodegenerative diseases has been the driving force behind the renewed interest in a field where biophysics, neurobiology and nanotechnology converge in the study of the aggregate state. On one hand, knowledge of the molecular principles that govern the processes of protein aggregation has a direct impact on the design of new drugs for high-incidence pathologies that currently can only be treated palliatively. On the other hand, exploiting the benefits of protein aggregation in the design of new nanomaterials could have a strong impact on biotechnology...
September 13, 2017: Biophysical Reviews
keyword
keyword
19043
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

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

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

Use quotes to search for an exact phrase

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