scholarly journals Genetic engineering of marine cyanophages reveals integration but not lysogeny in T7-like cyanophages

2021 ◽  
Author(s):  
Dror Shitrit ◽  
Thomas Hackl ◽  
Raphael Laurenceau ◽  
Nicolas Raho ◽  
Michael C. G. Carlson ◽  
...  
Keyword(s):  
Genetic Engineering ◽  
Attachment Site ◽  
Marine Cyanobacteria ◽  
Engineering System ◽  
Pcr Screening ◽  
Photosynthetic Organisms ◽  
Infection Dynamics ◽  
Attachment Sites ◽  
Insight Into

AbstractMarine cyanobacteria of the genera Synechococcus and Prochlorococcus are the most abundant photosynthetic organisms on earth, spanning vast regions of the oceans and contributing significantly to global primary production. Their viruses (cyanophages) greatly influence cyanobacterial ecology and evolution. Although many cyanophage genomes have been sequenced, insight into the functional role of cyanophage genes is limited by the lack of a cyanophage genetic engineering system. Here, we describe a simple, generalizable method for genetic engineering of cyanophages from multiple families, that we named REEP for REcombination, Enrichment and PCR screening. This method enables direct investigation of key cyanophage genes, and its simplicity makes it adaptable to other ecologically relevant host-virus systems. T7-like cyanophages often carry integrase genes and attachment sites, yet exhibit lytic infection dynamics. Here, using REEP, we investigated their ability to integrate and maintain a lysogenic life cycle. We found that these cyanophages integrate into the host genome and that the integrase and attachment site are required for integration. However, stable lysogens did not form. The frequency of integration was found to be low in both lab cultures and the oceans. These findings suggest that T7-like cyanophage integration is transient and is not part of a classical lysogenic cycle.

scholarly journals Recombinant human thrombomodulin. Regulation of cofactor activity and anticoagulant function by a glycosaminoglycan side chain

1992 ◽  
Vol 283 (1) ◽  
pp. 151-157 ◽  
Author(s):  
J F Parkinson ◽  
C J Vlahos ◽  
S C B Yan ◽  
N U Bang
Keyword(s):  
Chondroitin Sulphate ◽  
Attachment Site ◽  
Side Chain ◽  
Thrombin Receptor ◽  
Attachment Sites ◽  
Glycosylation Sites ◽  
293 Cells ◽  
Epidermal Growth ◽  
Anticoagulant Function

Two glycoforms of a secretable human thrombomodulin mutant [TMD1-105 and TMD1-75; Parkinson, Grinnell, Moore, Hoskins, Vlahos & Bang (1990) J. Biol. Chem. 265, 12602-12610] were expressed in human 293 cells and used to study the role of glycosylation in the functions of this endothelial-cell thrombin receptor. Carbohydrate content analysis and intrinsic labelling with [3H]glucosamine and [35S]sulphate showed that TMD1-105 contained a chondroitin sulphate whereas TMD1-75 did not. Other than chondroitin sulphate, the carbohydrate contents of the two glycoforms were identical, indicating similar glycosylation patterns at other O-linked and N-linked sites in the two glycoforms. The properties of TMD1-105 were converted into those of TMD1-75 by chondroitin ABC lyase digestion. Trypsin digestion of labelled TMD1-105 permitted isolation of two overlapping peptides that contained chondroitin sulphate, spanned the entire O-glycosylation domain and had O-glycosylation sites at Ser-492, Ser-498, Thr-500, Thr-504 and Thr-506. The chondroitin sulphate-attachment site was assigned to Ser-492 as this residue is conserved in mouse and bovine thrombomodulin and lies within a sequence Ser-Gly-Ser-492-Gly-Glu-Pro, which has strong similarity to chondroitin sulphate attachment sites in other proteoglycans. Five peptides with N-linked carbohydrate were also isolated and contained glycosylation sites in the lectin-like domain (Asn-47, Asn-115, Asn-116) and in the fourth (Asn-382) and fifth (Asn-409) epidermal growth factor domains. The role of N-linked and simple O-linked carbohydrates in the functions of human thrombomodulin remain unclear. The present studies demonstrate, however, that the presence of chondroitin sulphate in human thrombomodulin has profound effects on all of the anticoagulant properties of this important anticoagulant thrombin receptor.

scholarly journals Scx-positive tendon cells are required for correct muscle patterning

2021 ◽  
Author(s):  
Yudai Ono ◽  
Tempei Sato ◽  
Chisa Shukunami ◽  
Hiroshi Asahara ◽  
Masafumi Inui
Keyword(s):  
Skeletal Muscles ◽  
Essential Role ◽  
Cell Lineage ◽  
Attachment Site ◽  
Muscle Bundle ◽  
Muscle Attachment ◽  
Attachment Sites ◽  
Tendon Cells ◽  
Muscle Attachment Sites

SummaryThe elaborate movement of the vertebrate body is supported by the precise connection of muscle, tendon and bone. Each of the >600 distinct skeletal muscles in the human body has unique attachment sites; however, the mechanism through which muscles are reproducibly attached to designated partner tendons during embryonic development is incompletely understood. We herein show that Screlaxis-positive tendon cells have an essential role in correct muscle attachment in mouse embryos. Specific ablation of Screlaxis-positive cells resulted in dislocation of muscle attachment sites and abnormal muscle bundle morphology. Step-by-step observation of myogenic cell lineage revealed that post-fusion myofibers, but not migrating myoblasts, require tendon cells for their morphology. Furthermore, muscles could change their attachment site, even after the formation of the insertion. Our study demonstrated an essential role of tendon cells in the reproducibility and plasticity of skeletal muscle patterning, in turn revealing a novel tissue-tissue interaction in musculoskeletal morphogenesis.Graphical abstract

scholarly journals A novel computational approach to reconstruct SARS-CoV-2 infection dynamics through the inference of unsampled sources of infection

2021 ◽  
Author(s):  
Deshan Perera ◽  
Ben Perks ◽  
Michael Potemkin ◽  
Paul Gordon ◽  
John Gill ◽  
...  
Keyword(s):  
New York ◽  
Disease Transmission ◽  
New York State ◽  
Transmission Network ◽  
Transmission Networks ◽  
Mobile Populations ◽  
Infection Dynamics ◽  
Sources Of Infection ◽  
Insight Into

ABSTRACTInfectious diseases such as the COVID19 pandemic cemented the importance of disease tracking. The role of asymptomatic, undiagnosed individuals in driving infection has become evident. Their unaccountability results in ineffective prevention. We developed a pipeline using genomic data to accurately predict a population’s transmission network complete with the inference of unsampled sources. The system utilises Bayesian phylogenetics to capture evolutionary and infection dynamics of SARS-CoV-2. It identified the effectiveness of preventive measures in Canada’s Atlantic bubble and mobile populations such as New York State. Its robustness extends to the prediction of cross-species disease transmission as we inferred SARS-CoV-2 transmission from humans to lions and tigers in New York City’s Bronx Zoo. The proposed method’s ability to generate such complete transmission networks, provides a more detailed insight into the transmission dynamics within a population. This potential frontline tool will be of direct help in “the battle to bend the curve”.

Plasminogen Activation In Vivo upon Intravenous Infusion of DDAVP

1992 ◽  
Vol 67 (01) ◽  
pp. 111-116 ◽  
Author(s):  
Marcel Levi ◽  
Jan Paul de Boer ◽  
Dorina Roem ◽  
Jan Wouter ten Cate ◽  
C Erik Hack
Keyword(s):  
Monoclonal Antibodies ◽  
Plasminogen Activator ◽  
Plasma Levels ◽  
Fold Increase ◽  
Fibrinolytic System ◽  
Plasminogen Activation ◽  
Plasminogen Activator Activity ◽  
Insight Into

SummaryInfusion of desamino-d-arginine vasopressin (DDAVP) results in an increase in plasma plasminogen activator activity. Whether this increase results in the generation of plasmin in vivo has never been established.A novel sensitive radioimmunoassay (RIA) for the measurement of the complex between plasmin and its main inhibitor α2 antiplasmin (PAP complex) was developed using monoclonal antibodies preferentially reacting with complexed and inactivated α2-antiplasmin and monoclonal antibodies against plasmin. The assay was validated in healthy volunteers and in patients with an activated fibrinolytic system.Infusion of DDAVP in a randomized placebo controlled crossover study resulted in all volunteers in a 6.6-fold increase in PAP complex, which was maximal between 15 and 30 min after the start of the infusion. Hereafter, plasma levels of PAP complex decreased with an apparent half-life of disappearance of about 120 min. Infusion of DDAVP did not induce generation of thrombin, as measured by plasma levels of prothrombin fragment F1+2 and thrombin-antithrombin III (TAT) complex.We conclude that the increase in plasminogen activator activity upon the infusion of DDAVP results in the in vivo generation of plasmin, in the absence of coagulation activation. Studying the DDAVP induced increase in PAP complex of patients with thromboembolic disease and a defective plasminogen activator response upon DDAVP may provide more insight into the role of the fibrinolytic system in the pathogenesis of thrombosis.

On Metaphysics and the Political: A Polemics of Reading Baudelaire in the 1930s

2019 ◽  
Vol 58 (2) ◽  
pp. 249-259
Author(s):  
Joseph Acquisto
Keyword(s):  
Twentieth Century ◽  
Political Crisis ◽  
The Political ◽  
Modern Poetry ◽  
Progressive Politics ◽  
The World ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

This essay examines a polemic between two Baudelaire critics of the 1930s, Jean Cassou and Benjamin Fondane, which centered on the relationship of poetry to progressive politics and metaphysics. I argue that a return to Baudelaire's poetry can yield insight into what seems like an impasse in Cassou and Fondane. Baudelaire provides the possibility of realigning metaphysics and politics so that poetry has the potential to become the space in which we can begin to think the two of them together, as opposed to seeing them in unresolvable tension. Or rather, the tension that Baudelaire animates between the two allows us a new way of thinking about the role of esthetics in moments of political crisis. We can in some ways see Baudelaire as responding, avant la lettre, to two of his early twentieth-century readers who correctly perceived his work as the space that breathes a new urgency into the questions of how modern poetry relates to the world from which it springs and in which it intervenes.

Dažu vācu muzikālo tradīciju pārnese latviešu kultūrtelpā 18. gadsimta II pusē

Letonica ◽  
2020 ◽  
Author(s):  
Māra Grudule
Keyword(s):  
18Th Century ◽  
Musical Instrument ◽  
German Society ◽  
Original Form ◽  
Musical Life ◽  
Popular Songs ◽  
Death Of Jesus ◽  
Musical Traditions ◽  
Insight Into

The article gives insight into a specific component of the work of Baltic enlightener Gotthard Friedrich Stender (1714–1796) that has heretofore been almost unexplored — the transfer of German musical traditions to the Latvian cultural space. Even though there are no sources that claim that Stender was a composer himself, and none of his books contain musical notation, the texts that had been translated by Stender and published in the collections “Jaunas ziņģes” (New popular songs, 1774) and “Ziņģu lustes” (The Joy of singing, 1785, 1789) were meant for singing and, possibly, also for solo-singing with the accompaniment of some musical instrument. This is suggested, first, by how the form of the translation corresponds to the original’s form; second, by the directions, oftentimes attached to the text, that indicate the melody; and third, by the genres of the German originals cantata and song. Stender translated several compositions into Latvian including the text of the religious cantata “Der Tod Jesu” (The Death of Jesus, 1755) by composer Karl Heinrich Graun (1754–1759); songs by various composers that were widely known in German society; as well as a collection of songs by the composer Johann Gottlieb Naumann (1741–1801) that, in its original form, was published together with notation and was intended for solo-singing (female vocals) with the accompaniment of a piano. This article reveals the context of German musical life in the second half of the 18th century and explains the role of music as an instrument of education in Baltic-German and Latvian societies.

The Role of Industry-Academia Collaborative Research in Mineral Exploration

2020 ◽  
Author(s):  
James Marlatt
Keyword(s):  
Collaborative Research ◽  
New Technologies ◽  
Mineral Exploration ◽  
Board Members ◽  
Technological Innovations ◽  
Development Programs ◽  
The University ◽  
Insight Into ◽  
Economic Mineral

ABSTRACT Many people may not be aware of the extent of Kurt Kyser's collaboration with mineral exploration companies through applied research and the development of innovative exploration technologies, starting at the University of Saskatchewan and continuing through the Queen's Facility for Isotope Research. Applied collaborative, geoscientific, industry-academia research and development programs can yield technological innovations that can improve the mineral exploration discovery rates of economic mineral deposits. Alliances between exploration geoscientists and geoscientific researchers can benefit both parties, contributing to the pure and applied geoscientific knowledge base and the development of innovations in mineral exploration technology. Through a collaboration that spanned over three decades, we gained insight into the potential for economic uranium deposits around the world in Canada, Australia, USA, Finland, Russia, Gabon, Namibia, Botswana, South Africa, and Guyana. Kurt, his research team, postdoctoral fellows, and students developed technological innovations related to holistic basin analysis for economic mineral potential, isotopes in mineral exploration, and biogeochemical exploration, among others. In this paper, the business of mineral exploration is briefly described, and some examples of industry-academic collaboration innovations brought forward through Kurt's research are identified. Kurt was a masterful and capable knowledge broker, which is a key criterion for bringing new technologies to application—a grand, curious, credible, patient, and attentive communicator—whether talking about science, business, or life and with first ministers, senior technocrats, peers, board members, first nation peoples, exploration geologists, investors, students, citizens, or friends.

Gender Differences in Empathy During Adolescence: Does Emotional Self-Awareness Matter?

2021 ◽  
pp. 003329412097663
Author(s):  
Cristina Trentini ◽  
Renata Tambelli ◽  
Silvia Maiorani ◽  
Marco Lauriola
Keyword(s):  
Gender Differences ◽  
Reactivity Index ◽  
Self Awareness ◽  
Emotional States ◽  
Personal Distress ◽  
Full Knowledge ◽  
Emotional Concern ◽  
Insight Into ◽  
Tas 20

Empathy refers to the capacity to experience emotions similar to those observed or imagined in another person, with the full knowledge that the other person is the source of these emotions. Awareness of one's own emotional states is a prerequisite for self-other differentiation to develop. This study investigated gender differences in empathy during adolescence and tested whether emotional self-awareness explained these differences. Two-hundred-eleven adolescents (108 girls and 103 boys) between 14 and 19 years completed the Interpersonal Reactivity Index (IRI) and the Toronto Alexithymia Scale (TAS-20) to assess empathy and emotional self-awareness, respectively. Overall, girls obtained higher scores than boys on IRI subscales like emotional concern, personal distress, and fantasy. Regarding emotional self-awareness, we found gender differences in TAS-20 scores, with girls reporting greater difficulty identifying feelings and less externally oriented thinking than boys. Difficulty identifying feelings explained the greatest personal distress experienced by girls. Lower externally oriented thinking accounted for girls’ greater emotional concern and fantasy. These findings offer an insight into the role of emotional self-awareness–which is essential for self-other differentiation–as an account for gender differences in empathic abilities during adolescence. In girls, difficulty identifying feelings can impair the ability to differentiate between ones’ and others’ emotions, leading them to experience self-focused and aversive responses when confronted with others’ suffering. Conversely, in boys, externally oriented thinking can mitigate personal distress when faced with others’ discomfort.

scholarly journals Salicylic Acid Accumulation Controlled by LSD1 Is Essential in Triggering Cell Death in Response to Abiotic Stress

Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 962
Author(s):  
Maciej Jerzy Bernacki ◽  
Anna Rusaczonek ◽  
Weronika Czarnocka ◽  
Stanisław Karpiński
Keyword(s):  
Cell Death ◽  
Salicylic Acid ◽  
Abiotic Stress ◽  
Wild Type ◽  
Pr Genes ◽  
Genes Expression ◽  
Salicylic Acid Accumulation ◽  
Cell Death Phenotype ◽  
Insight Into

Salicylic acid (SA) is well known hormonal molecule involved in cell death regulation. In response to a broad range of environmental factors (e.g., high light, UV, pathogens attack), plants accumulate SA, which participates in cell death induction and spread in some foliar cells. LESION SIMULATING DISEASE 1 (LSD1) is one of the best-known cell death regulators in Arabidopsis thaliana. The lsd1 mutant, lacking functional LSD1 protein, accumulates SA and is conditionally susceptible to many biotic and abiotic stresses. In order to get more insight into the role of LSD1-dependent regulation of SA accumulation during cell death, we crossed the lsd1 with the sid2 mutant, caring mutation in ISOCHORISMATE SYNTHASE 1(ICS1) gene and having deregulated SA synthesis, and with plants expressing the bacterial nahG gene and thus decomposing SA to catechol. In response to UV A+B irradiation, the lsd1 mutant exhibited clear cell death phenotype, which was reversed in lsd1/sid2 and lsd1/NahG plants. The expression of PR-genes and the H2O2 content in UV-treated lsd1 were significantly higher when compared with the wild type. In contrast, lsd1/sid2 and lsd1/NahG plants demonstrated comparability with the wild-type level of PR-genes expression and H2O2. Our results demonstrate that SA accumulation is crucial for triggering cell death in lsd1, while the reduction of excessive SA accumulation may lead to a greater tolerance toward abiotic stress.

scholarly journals Theoretical Insight into the Reversal of Chemoselectivity in Diels-Alder Reactions of α,β-Unsaturated Aldehydes and Ketones Catalyzed by Brønsted and Lewis Acids

Organics ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 38-49
Author(s):  
Lakhdar Benhamed ◽  
Sidi Mohamed Mekelleche ◽  
Wafaa Benchouk
Keyword(s):  
Lewis Acids ◽  
Major Product ◽  
Diels Alder ◽  
Unsaturated Ketone ◽  
Unsaturated Aldehydes ◽  
Aldehydes And Ketones ◽  
Theoretical Insight ◽  
Insight Into ◽  
Good Agreement

Experimentally, a reversal of chemoselectivity has been observed in catalyzed Diels–Alder reactions of α,β-unsaturated aldehydes (e.g., (2E)-but-2-enal) and ketones (e.g., 2-hexen-4-one) with cyclopentadiene. Indeed, using the triflimidic Brønsted acid Tf2NH as catalyst, the reaction gave a Diels–Alder adduct derived from α,β-unsaturated ketone as a major product. On the other hand, the use of tris(pentafluorophenyl)borane B(C6F5)3 bulky Lewis acid as catalyst gave mainly the cycloadduct of α,β-unsaturated aldehyde as a major product. Our aim in the present work is to put in evidence the role of the catalyst in the reversal of the chemoselectivity of the catalyzed Diels–Alder reactions of (2E)-but-2-enal and 2-Hexen-4-one with cyclopentadiene. The calculations were performed at the ωB97XD/6-311G(d,p) level of theory and the solvent effects of dichloromethane were taken into account using the PCM solvation model. The obtained results are in good agreement with experimental outcomes.

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