Crucial Sites Research Articles

Reviewing the Impact of Military Activities on Marine Biodiversity and Conservation: A Study of the Ukraine-Russia Conflict within the Framework of International Law

The severe consequences of military activities on marine biodiversity and conservation have come to limelight as a result of the Ukraine-Russian conflicts in the Black Sea region. The battle has had both immediate and collateral environmental effects on the Black Sea, a hotspot for numerous and uncommon aquatic species. Oil spills, the discharge of toxic substances, and habitat deterioration are only a few of the direct effects that have harmed marine environments and destroyed crucial breeding sites. The fragile balance of the marine life in the area is further threatened by indirect effects caused by fishing practices, increased marine traffic, and advances in coastal infrastructure brought on by conflicts. This ongoing conflict has infringed upon international agreements, including the Basel, Stockholm, and London Conventions, through military activities in the Black Sea, resulting in the violation of regulations governing hazardous waste movement and posing a threat to the biodiversity of the region. This review discusses the breaches and analyzes the harms caused in the marine ecosystem and resources and proposes suggestions as to combine military tactics with conservation activities.

Design, Synthesis, and Antifungal Activity of N-(alkoxy)-Diphenyl Ether Carboxamide Derivates as Novel Succinate Dehydrogenase Inhibitors.

Succinate dehydrogenase (SDH, EC 1.3.5.1) is one of the most promising targets for fungicide development and has attracted great attention worldwide. However, existing commercial fungicides targeting SDH have led to the increasingly prominent problem of pathogen resistance, so it is necessary to develop new fungicides. Herein, we used a structure-based molecular design strategy to design and synthesize a series of novel SDHI fungicides containing an N-(alkoxy)diphenyl ether carboxamide skeleton. The mycelial growth inhibition experiment showed that compound M15 exhibited a very good control effect against four plant pathogens, with inhibition rates of more than 60% at a dose of 50 μg/mL. A structure-activity relationship study found that N-O-benzyl-substituted derivatives showed better antifungal activity than others, especially the introduction of a halogen on the benzyl. Furthermore, the molecular docking results suggested that π-π interactions with Trp35 and hydrogen bonds with Tyr33 and Trp173 were crucial interaction sites when inhibitors bound to SDH. Morphological observation of mycelium revealed that M15 could inhibit the growth of mycelia. Moreover, in vivo and in vitro tests showed that M15 not only inhibited the enzyme activity of SDH but also effectively protected rice from damage due to R. solani infection, with a result close to that of the control at a concentration of 200 μg/mL. Thus, the N-(alkoxy)diphenyl ether carboxamide skeleton is a new starting point for the discovery of new SDH inhibitors and is worthy of further investigation.

Middle Passages: Lessons in Racial Subjection at the Hampton Institute and Carlisle Indian Industrial School

Abstract: This essay argues that the historically Black Hampton Institute (1868) and the Carlisle Indian Industrial School (1879) are crucial sites to investigate how US political, territorial, and economic conquest were sutured to the project of emancipation after the Civil War. Rather than focusing on these schools’ manual education, I turn to their newspapers, the Southern Workman and Indian Helper , to demonstrate how they developed techniques of discursive representation, rooted in Black fungibility, that made racial subjection appear as racial emancipation in the postbellum period. These newspapers were framed as both tool and evidence of students’ subjective transformation. Instead of providing authentic evidence of Black and Native transformation, however, they provide a glimpse into how Hampton’s and Carlisle’s representations of racial emancipation drew on discursive techniques created in the material and symbolic violence of transatlantic slavery’s Middle Passage. The essay concludes by demonstrating how a trio of boarding school stories (1900) by the Yankton Sioux author Zitkala-Ša provides a nascent critique of the ways in which Indian boarding schools produced Native fungibility as a technique of white domination in the context of postbellum US imperialism.

Mechanochemical synthesis of biochar encapsulated FeMn nanoparticles with strong metal–carbon interactions for efficient degradation of tetracycline via activating peroxymonosulfate

Transition metal and carbon nanomaterials are well-known for their peroxymonosulfate (PMS) activation capabilities. However, metal-based materials often suffer from ion leakage and poor reusability, while carbon-based materials have limited catalytic efficiency. To overcome these challenges and leverage the strengths of both, we introduce carbon-coated Fe/Mn composites (FeMn@BC), that establish strong interactions between metal components and the carbon substrate. FeMn@BC exhibited exceptional selectivity for 1O2 generation via PMS activation. In practical applications, FeMn@BC efficiently degraded tetracycline by activating PMS, achieving 99.1% removal in just 30 min. Importantly, FeMn@BC demonstrated remarkable stability, especially under visible light exposure. XPS analyses revealed strong interactions between FeMn components and the biochar shell, enhancing the electron transfer capacity of FeMn@BC through Fe(III)/Fe(II) and Mn(III)/Mn(II) redox pairs. In-situ attenuated total reflection Fourier-transform infrared (ATR-FTIR) analysis highlighted abundant hydroxyl groups in FeMn@BC as crucial active sites for electron transfer. Quenching experiments and electron paramagnetic resonance (EPR) measurements unveiled that FeMn@BC catalyzed 1O2 generation primarily through the disproportionation of O2− and energy transfer from oxygen vacancy to O2. Our work demonstrates the possibility of simple ball milling of biomass in the presence of iron salts for iron-catalyzed mechanochemical synthesis of biochar-based catalysts. This study not only presents a novel strategy for large-scale biochar-encapsulated transition metal catalyst synthesis but also explores the potential use of agricultural waste for value-added applications.

Biochar-Based Single-Atom Catalyst with Fe-N3O-C Configuration for Efficient Degradation of Organic Dyes by Peroxymonosulfate Activation.

Iron single-atom catalysts (Fe SACs) hold great promise for peroxymonosulfate (PMS) activation and degradation of organic pollutants in wastewater. However, insights into crucial catalytic sites and activation mechanisms of biochar-based Fe SACs for PMS remain a challenge. Herein, cotton stalk-derived biochar-based Fe SACs (Fe SACs-BC) with an asymmetric Fe-N/O-C configuration were prepared, and their PMS activation and acid orange 7 (AO7) degradation mechanisms were investigated. The results showed that the removal efficiency of the Fe SACs-BC catalyst with Fe-N3O-C configuration for AO7 and other five investigated organic dyes reached 95-99% within 15 min. The EPR spectrums, quenching experiments, electrochemical analysis, masking experiments, XPS, and theoretical calculations indicated that degradations of organic dyes were dominated by singlet oxygen, which was generated by direct PMS conversion at the electron-deficient carbon and iron sites in the Fe-N3O-C configuration. The Fe SACs-BC/PMS exhibited high removal efficiency and strong tolerance in different water matrices with a wide pH range, various coexisting anions and interfering substances, showing great potential and applicability for efficient treatment of actual textile wastewaters.

Stimulation of ATP Hydrolysis by ssDNA Provides the Necessary Mechanochemical Energy for G4 Unfolding

The G-quadruplex (G4) is a distinct geometric and electrophysical structure compared to classical double-stranded DNA, and its stability can impede essential cellular processes such as replication, transcription, and translation. This study focuses on the BsPif1 helicase, revealing its ability to bind independently to both single-stranded DNA (ssDNA) and G4 structures. The unfolding activity of BsPif1 on G4 relies on the presence of a single tail chain, and the covalent continuity between the single tail chain and the G4′s main chain is necessary for efficient G4 unwinding. This suggests that ATP hydrolysis-driven ssDNA translocation exerts a pull force on G4 unwinding. Molecular dynamics simulations identified a specific region within BsPif1 that contains five crucial amino acid sites responsible for G4 binding and unwinding. A “molecular wire stripper” model is proposed to explain BsPif1′s mechanism of G4 unwinding. These findings provide a new theoretical foundation for further exploration of the G4 development mechanism in Pif1 family helicases.

Leaf-cutter ants - mycorrhizal fungi: observations and research questions from an unexpected mutualism.

Leaf-cutter ants (LCAs) are widely distributed and alter the physical and biotic architecture above and below ground. In neotropical rainforests, they create aboveground and belowground disturbance gaps that facilitate oxygen and carbon dioxide exchange. Within the hyperdiverse neotropical rainforests, arbuscular mycorrhizal (AM) fungi occupy nearly all of the forest floor. Nearly every cubic centimeter of soil contains a network of hyphae of Glomeromycotina, fungi that form arbuscular mycorrhizae. Our broad question is as follows: how can alternative mycorrhizae, which are-especially ectomycorrhizae-essential for the survival of some plant species, become established? Specifically, is there an ant-mycorrhizal fungus interaction that facilitates their establishment in these hyperdiverse ecosystems? In one lowland Costa Rican rainforest, nests of the LCA Atta cephalotes cover approximately 1.2% of the land surface that is broadly scattered throughout the forest. On sequencing the DNA from soil organisms, we found the inocula of many AM fungi in their nests, but the nests also contained the inocula of ectomycorrhizal, orchid mycorrhizal, and ericoid mycorrhizal fungi, including Scleroderma sinnamariense, a fungus critical to Gnetum leyboldii, an obligate ectomycorrhizal plant. When the nests were abandoned, new root growth into the nest offered opportunities for new mycorrhizal associations to develop. Thus, the patches created by LCAs appear to be crucial sites for the establishment and survival of shifting mycorrhizal plant-fungal associations, in turn facilitating the high diversity of these communities. A better understanding of the interactions of organisms, including cross-kingdom and ant-mycorrhizal fungal interactions, would improve our understanding of how these ecosystems might tolerate environmental change.

Leveraging the Fragment Molecular Orbital Method to Explore the PLK1 Kinase Binding Site and Polo-Box Domain for Potent Small-Molecule Drug Design.

Polo-like kinase 1 (PLK1) plays a pivotal role in cell division regulation and emerges as a promising therapeutic target for cancer treatment. Consequently, the development of small-molecule inhibitors targeting PLK1 has become a focal point in contemporary research. The adenosine triphosphate (ATP)-binding site and the polo-box domain in PLK1 present crucial interaction sites for these inhibitors, aiming to disrupt the protein's function. However, designing potent and selective small-molecule inhibitors can be challenging, requiring a deep understanding of protein-ligand interaction mechanisms at these binding sites. In this context, our study leverages the fragment molecular orbital (FMO) method to explore these site-specific interactions in depth. Using the FMO approach, we used the FMO method to elucidate the molecular mechanisms of small-molecule drugs binding to these sites to design PLK1 inhibitors that are both potent and selective. Our investigation further entailed a comparative analysis of various PLK1 inhibitors, each characterized by distinct structural attributes, helping us gain a better understanding of the relationship between molecular structure and biological activity. The FMO method was particularly effective in identifying key binding features and predicting binding modes for small-molecule ligands. Our research also highlighted specific "hot spot" residues that played a critical role in the selective and robust binding of PLK1. These findings provide valuable insights that can be used to design new and effective PLK1 inhibitors, which can have significant implications for developing anticancer therapeutics.

“Politics of Plastic Nationhood”: Sokol Mass Gymnastics and Eugenics Between Empire and Nation-States

Abstract This article examines how mass gymnastics in East Central Europe became increasingly entangled with eugenics. It traces the proliferation of eugenic discourses alongside the medicalization of gymnastics within Sokol, a mass nationalist voluntary association. In this context, the bodies of gymnasts became crucial sites of knowledge production and ideological projection. The article introduces the “politics of plastic nationhood,” a concept that foregrounds the fierce debates within Sokol over strategies to shape the imagined body of the nation though physical exercise. It also highlights key actors in these discussions, including medical doctors, physical anthropologists, and gymnastics trainers. The article shows that four major themes shaped these biopolitical disputes: health, diversity, gender, and ability. Focusing specifically on Sokol associations in interwar Czechoslovakia and Yugoslavia and their prewar predecessors, the article outlines a chronology of the politics of plastic nationhood, which emerged in the Habsburg Empire and reached their zenith in the successor states. After imperial collapse, in particular, Sokol eugenicists sought to merge the diverse Slavic populations of the new states into a single “national body.” Owing to their perceived failure to achieve national unity, starting in the mid-1930s onward, eugenicists turned to rigid racial hierarchies, statism, and authoritarian politics.

BOLLYWOOD AS A SITE FOR CREATING COLLECTIVE MEMORY: A CASE STUDY OF SELECT MOVIES

Memory like history have and will always remain sites for discursive struggle wherein institutional mechanisms will continuously try to control and shape it. Throughout history, mass media has been one of major tools that various actors have used to shape the discursive struggle of history and memory simultaneously. Both of them serve as crucial sites of resistance for the disenfranchised groups.Mass media in the form of cinema has always been a crucial site for this discursive struggle for both memory and history. In the present-day visual culture, Television and cinema have emerged as major sources from where we get to know about glorious histories, past struggles, and triumphs. Be it biographical series or movies, fictionalized accounts of war memorialized into blockbuster movies, or state commissioned actualities/documentaries; the cinematic representation caters to collective re-imagination of past events and renders them into sites for shaping collective memory and thus identity.During WWII, both Hitler and Stalin used films as tools for propaganda as this medium has potential to shape one’s understanding of history. State and non- state actors throughout history have used cinema to establish, reinforce and even mold historical events into hyper-emotionalized audio-visual texts, which over a period naturalizes or blurs the lines between real and represented history.This paper will focus on how content and transmission of popular memory via cinema in India takes place. The focus will be on how mass media in the shape of cinema reinforce the existing mnemonic hegemony, which in turn shapes collective identities and pasts of the public.Engaging with political economy the paper will further examine how economic conditions shape popular memory simultaneously leading to erasure of certain histories. The concept is to investigate how social, economic, and political circumstances indirectly encourage and exclude specific narratives in order to sustain dominant power dynamics in collective recollection across different races, classes, and genders through the medium of cinema.The premise is to not only understand mass media content act as an agency to the production and sustaining of memory but also highlight the various factors behind this materialist approach of memory leading to erasure and disenfranchisement of other histories and memories. This involves interrogating the ownership, production, and consumption of memories propagated through television and cinema in India.

Superman as the Measure of All Things: Black Gods and White Saviours in Watchmen and Doomsday Clock

Abstract While the groundbreaking graphic novel Watchmen (1986) responded to Cold War paranoia with a nihilistic critique of a benevolent God, recent spinoffs have taken radically different approaches to race and Christology in the Trump Era. Alan Moore and Dave Gibbons’ original Watchmen has spawned two unlikely and unauthorised—by Moore, at least—quasi-sequels in different media: HBO’s limited TV series Watchmen (2019), created by Damon Lindelof, and Geoff Johns and Gary Frank’s graphic novel Doomsday Clock (2020). Like estranged siblings, HBO’s Watchmen and Doomsday Clock take the same source material in opposite directions. HBO’s Watchmen explores themes of racial justice by foregrounding 1921’s Tulsa Massacre and vesting Black characters with divine power. In contrast, Doomsday Clock departs from the original Watchmen’s cynicism about cultural and political change, embodying its message of hope and renewal in a white saviour. This article contributes to the growing body of literature examining how pop culture circulates Christological concepts by exploring the racial and theological significance of two of DC Comics’ most iconic characters—Superman and Dr Manhattan. I examine how Black theologians conceptualise Christology, discuss the deistic portrayal of Dr Manhattan in the original Watchmen, analyse the character’s incarnational iteration in the television series, and contrast this with how moral influence Christology underpins the relationship between Superman and Dr Manhattan in Doomsday Clock to show that superhero comics in particular, and pop culture more broadly, are crucial sites of Christological imagination and negotiation over race.

Understanding the GABAA Receptor: Implications for Anesthesia and Beyond

AbstractGamma-aminobutyric acid (GABA), a nonpeptide amino acid transmitter, is a major component of modern neuropharmacology and one of the most crucial target sites for general anesthetics and therapeutic drugs. GABA type A receptors (GABAARs) are the most abundant inhibitory neurotransmitter receptors in the central nervous system. They are part of the rapid-acting, ligand-gated ion channel (LGIC) receptor category, a pentameric Cys-loop superfamily member that mediates inhibitory neurotransmission in the mature brain. GABAARs mainly consist of two α subunits, two β subunits, and one additional subunit from either γ or δ arranged around a central chloride (Cl-) selective channel. Multiple GABAAR subunit subtypes and splice variants have been identified. Each variant of GABAAR exhibits distinct biophysical and pharmacologic properties. Several compounds allosterically modulate the GABAAR positively or negatively. The widely used positive GABAAR modulators include benzodiazepines (anxiolytic and anticonvulsant), general anesthetics (volatile agents like isoflurane, and intravenous agents like barbiturates, etomidate, and propofol), long-chain alcohols, some anticonvulsants, and neuroactive steroids. The binding sites for each drug are distinctly different. The anesthetic drugs enhance receptor-mediated synaptic transmission and thus interrupt the thalamocortical transmission, which controls the sleep–wake patterns. Abnormality in the GABAAR function has been implicated in several neurological conditions, such as sleep disorders, seizures, depression, cognitive function, neurological recovery after injury, and neuroplasticity. Understanding the GABAAR lays the foundation for the development of highly specific drugs in the treatment of neurological disorders and general anesthesia.

Mutational analyses, pharmacophore-based inhibitor design and in silico validation for Zika virus NS3-helicase

Zika virus is responsible for causing Zika infections and was declared as a public health emergency of international concern in February 2016. The Zika virus NS3-helicase is a viable drug target for the design of inhibitors due to its essential role in the replication of viral genome. The viral RNA is unwound by the NS3-helicase in order to enable the reproduction of viral genome by the NS5 protein. Zika virus infections in humans are being reported for the last 15 years. We have therefore carried out amino acid mutational analyses of NS3-helicase. NS3-helicase has two crucial binding sites: the ATP and RNA binding sites. The cofactor-ATP based pharmacophore was generated for virtual screening of ZINC database using Pharmit server, that is followed by molecular docking and molecular dynamics simulations of potential hits as probable Zika virus NS3-helicase inhibitors at the cofactor binding site. The drug-like properties of the molecules were analysed and, DFT calculations were performed on the five best molecules to reveal their stability in solvent phase compared to gas phase, the HOMO and LUMO and electrostatic potential maps to analyze the electronic and geometric characteristics. These are significant findings towards the discovery of new inhibitors of Zika virus NS3-helicase, a promising drug target to treat the Zika virus infection. Communicated by Ramaswamy H. Sarma

Functional Mutations in the microRNA-155 Promoter Modulate its Transcription Efficiency and Expression.

Limited research has been conducted on porcine miR-155 promoters, and previous study from our group have identified two haplotypes (TT and CC) in different pig breeds, each associated with five fully linked mutation sites within or near the miR-155 gene (Li et al. Dev Comp Immunol 39(1):110-116, 2013). In this study, the promoter region of porcine miR-155 was screened, and two important transcription factors, Foxp3 and RelA, were identified. The binding ability of Foxp3 protein was found to be affected by the first mutation site (A/C) using EMSA analysis. In vitro experiments revealed that the expression level of miR-155 was significantly higher in the C haplotype compared to the T haplotype. Additionally, northern blotting assays indicated that both the first mutation site (A/C) and the fourth mutation site (G/T) had a significant impact on miR-155 expression levels. These findings provide further insights into the transcriptional regulation of porcine miR-155 and identify crucial mutation sites that influence miR-155 expression. This knowledge can serve as a basis for identifying potential molecular markers associated with disease resistance in swine.

On-the-Go Vis-NIR Spectroscopy for Field-Scale Spatial-Temporal Monitoring of Soil Organic Carbon

Agricultural soils serve as crucial storage sites for soil organic carbon (SOC). Their appropriate management is pivotal for mitigating climate change. Continuous monitoring is imperative to evaluate spatial and temporal changes in SOC within agricultural fields. In-field datasets of Vis-NIR soil spectra were collected on a long-term experimental site using an on-the-go spectrophotometer. Data processing for continuous SOC prediction involves a two-step modeling approach. In Step 1, a partial least square (PLSR) regression model is trained to establish a relationship between the SOC content and spectral information, including spectral preprocessing. In Step 2, the predicted SOC content obtained from the PLSR models is interpolated using ordinary kriging. Among the tested spectral preprocessing techniques and semivariogram models, Savitzky–Golay and the Gap-Segment derivative preprocessing along with a Gaussian semivariogram model, yielded the best performance resulting in a root mean square error of 1.24 and 1.26 g kg−1. A striping effect due to the transect-based data collection was addressed by testing the effectiveness of extending the spatial separation distance, employing data aggregation, and defining the distribution based on treatment plots using block kriging. Overall, the results highlight the high potential of on-the-go spectral Vis-NIR data for field-scale spatial-temporal monitoring of SOC.

Co-producing ethnicity in urban Asia

ABSTRACT The articles in this special issue examine engagements across ethnic boundaries in Asian cities over the past two centuries. We see these cities as stages for the co-production of ethnicity, where multiple actors, including but not limited to state authorities, have attempted to define, manage, and challenge the social boundaries between their diverse inhabitants. These articles direct our attention to the convergence of three critical themes: the flexibility and ubiquity of ethnic ascription, the top-down and bottom-up co-production of social meaning, and Asian cities as crucial sites of social innovation.

Design, synthesis and docking studies of novel 4-aminophenol-1,2,4-oxadiazole hybrids as apoptosis inducers against triple negative breast cancer cells targeting MAP kinase

In our study, a series of novel 4-aminophenol benzamide-1,2,4-oxadiazole hybrid analogues have been designed and synthesized by condensing 4-hydroxyphenyl arylamides (3a–c) and 5-chloromethyl-3-aryl-1,2,4-oxadiazoles (6a–d). The structure of the synthesised compounds was verified by various spectroscopic techniques (1H NMR, 13C NMR, IR and LC-MS). All the prepared compounds were subjected to in silico and in vitro antiproliferative study against TNBC cell lines MDA-MB-468 and MDA-MB-231. The investigations revealed that compound 7k significantly promoted apoptosis against MDA-MB-468 and MDA-MB-231 cells with IC50 values of 22.31 µM and 26.27 µM, respectively. Compound 7k interacted with crucial active sites of MAPK and exhibited the highest docking score of −7.06 kcal/mol. Docking was validated with molecular dynamic studies with simulation for 100 ns, depicting various stable interactions with MAPK. Consequently, 7k forms stable H-Bonds and π-π stacking with amino acid residues along with π-cation. Our investigations reveal that the in vitro antiproliferative study of 7k was in good correlation with the in silico studies. Hence, 7k serves as a potential novel lead for the inhibition of TNBCs by downregulating MAPK P38. Communicated by Ramaswamy H. Sarma

Barosmin against postprandial hyperglycemia: outputs from computational prediction to functional responses in vitro

Previously, barosmin has been demonstrated to possess anti-diabetic action. However, its effect to inhibit α-amylase and α-glucosidase, including glucose utilization efficacy, has yet to be revealed. Hence, the current study attempted to assess the efficiency of barosmin in inhibiting the α-amylase, α -glucosidase, and dipeptidyl peptidase 4 enzymes, including glucose uptake efficacy. Molecular docking and simulation were performed using AutoDock Vina and Gromacs respectively followed by gene ontology analysis using the database for annotation, visualization, and integrated discovery. Further, in vitro enzyme inhibitory activities and glucose uptake assay were performed in L6 cell lines. Density functional theory analysis detailed mechanistic insights into the crucial interaction sites of barosmin of which the electron-dense region was prone to nucleophilic attack (O-atoms) whereas hydroxyl groups (-OH) showed affinity for electrophilic attacks. Barosmin showed good binding affinity with α-amylase (-9.2 kcal/mol), α-glucosidase (-10.7 kcal/mol), and dipeptidyl peptidase 4 (-10.0 kcal/mol). Barosmin formed stable nonbonded contacts with active site residues of aforementioned enzymes throughout 200 ns molecular dynamics simulation. Further, it regulated pathway concerned with glucose homeostasis i.e. tumor necrosis factor signaling pathway. In addition, barosmin showed α-amylase (IC50= 95.77 ± 23.33 µg/mL), α-glucosidase (IC50= 68.13 ± 2.95 µg/mL), and dipeptidyl peptidase 4 (IC50= 13.27 ± 1.99 µg/mL) inhibitory activities including glucose uptake efficacy in L6 cell lines (EC50= 12.46 ± 0.90 µg/mL) in the presence of insulin. This study presents the efficacy of the barosmin to inhibit α-amylase and α-glucosidase and glucose uptake efficacy in L6 cell lines via the use of multiple system biology tools and in vitro techniques. Communicated by Ramaswamy H. Sarma

Multiple tectonic switches in the Eastern Tianshan, Central Asian Orogenic Belt: Implications for crustal growth and metallogenesis

Subduction zones are crucial sites for inputs of juvenile crust and the generation of porphyry copper deposits by arc magmatic processes that generally involve episodic trench advance and retreat. It is well documented that the generation of juvenile crust is associated with lithospheric extension during the retreat of subduction zones, whereas crustal reworking is associated with lithospheric compression in continental arcs during the advance of subduction zones. However, it remains unclear whether such models can be applied to island arc settings and how they relate to metallogenesis. To address this issue, we examine intermediate–felsic igneous rocks (∼460–300 Ma) of the Dananhu–Harlik island arc in the southern Central Asian Orogenic Belt. Our new and compiled data indicate three magmatic episodes in the Dananhu–Harlik island arc during the northward subduction of the Kangguer oceanic plate, with each involving a tectonic switch from compressional trench advance to extensional retreat. Crustal growth occurred mainly during the compressional stages of trench advance, which is in contrast with typical continental arcs. Tectonic transitions also controlled regional mineralization patterns, and the typical porphyry and related skarn-type deposits formed during subduction zone advance, whereas volcanogenic massive sulfide (VMS) deposits and overprinting mineralization were generated during subduction zone retreat. A combination of all data on tectonic settings and physical–chemical conditions (e.g., temperature, oxygen fugacity, and water content) of the pre-mineralization and ore-related intrusions led us to the conclusion that normal intra-crustal arc magmatic processes, involving sulfide pre-enrichment and reactivation, generated the typical Tuwu–Yandong porphyry Cu deposits in the Dananhu arc without the prerequisite of slab melting. Our study provides an excellent example of crustal growth in an island arc setting as well as metallogenesis during the repeated advance and retreat of a subduction zone.

Artificial Proteins Designed from G3LEA Contribute to Enhancement of Oxidation Tolerance in E. coli in a Chaperone-like Manner.

G3LEA is a family of proteins that exhibit chaperone-like activity when under distinct stress. In previous research, DosH was identified as a G3LEA protein from model extremophile-Deinococcus radiodurans R1 with a crucial core HD domain consisting of eight 11-mer motifs. However, the roles of motifs participating in the process of resistance to stress and their underlying mechanisms remain unclear. Here, eight different proteins with tandem repeats of the same motif were synthesized, named Motif1-8, respectively, whose function and structure were discussed. In this way, the role of each motif in the HD domain can be comprehensively analyzed, which can help in finding possibly crucial amino acid sites. Circular dichroism results showed that all proteins were intrinsically ordered in phosphate buffer, and changed into more α-helical ordered structures with the addition of trifluoroethanol and glycerol. Transformants expressing artificial proteins had significantly higher stress resistance to oxidation, desiccation, salinity and freezing compared with the control group; E. coli with Motif1 and Motif8 had more outstanding performance in particular. Moreover, enzymes and membrane protein protection viability suggested that Motif1 and Motif8 had more positive influences on various molecules, demonstrating a protective role in a chaperone-like manner. Based on these results, the artificial proteins synthesized according to the rule of 11-mer motifs have a similar function to wildtype protein. Regarding the sequence in all motifs, there are more amino acids to produce H bonds and α-helices, and more amino acids to promote interaction between proteins in Motif1 and Motif8; in addition, considering linkers, there are possibly more amino acids forming α-helix and binding substrates in these two proteins, which potentially provides some ideas for us to design potential ideal stress-response elements for synthetic biology. Therefore, the amino acid composition of the 11-mer motif and linker is likely responsible for its biological function.