S1 Site Research Articles

Assessing the water quality of River Ganga in Varanasi, India, through WQI, NPI, and multivariate techniques: a comprehensive study

Abstract In the present research water quality from nine different sampling points (S1–S9) from the River Ganga at Varanasi was examined for different water quality parameters, and multivariate statistical analyses were carried out. Subsequently, several indices, such as water quality index and Nemerow pollution index (NPI), were calculated. The results indicated that the Ganga River at Varanasi had high levels of coliform concentrations, altered pH, and elevated dissolved oxygen/biochemical oxygen demand and chemical oxygen demand values. The weighted arithmetic water quality index values revealed that sites S8, S9, and S2 were the most polluted and unfit for bathing and drinking. Most of the sampling sites have NPI values greater than 1 for several parameters, indicating high levels of pollution. The study revealed that the water quality is poor for bathing and drinking at most of the sites throughout the year. In addition, the upstream water quality assessment revealed that water quality was good compared with the heavily contaminated downstream region. This knowledge can be useful for environmentalists, policymakers, and water resource managers to develop strategic plans to preserve the cultural and aesthetic worth of the Ganga River in the future.

A study on effects of cell phone tower-emitted non-ionizing radiations in an Allium cepa test system.

Considering enormous growth in population, technical advancement, and added reliance on electronic devices leading to adverse health effects, in situ simulations were made to evaluate effects of non-ionizing radiations emitted from three cell phone towers (T1, T2, and T3) of frequency bands (800, 1800, 2300MHz), (900, 1800, 2300MHz), and (1800MHz), respectively. Five sites (S1-S5) were selected near cell phone towers exhibiting different power densities. The site with zero power density was considered as control. Effects of radiations were studied on morphology; protein content; antioxidant enzymes like ascorbate peroxidase (APX), superoxide dismutase (SOD), glutathione-S-transferase (GST), guaiacol peroxidase (POD), and glutathione reductase (GR); and genotoxicity using Allium cepa. Mean power density (μW/cm2) was recorded as 1.05, 1.18, 1.6, 2.73, and 12.9 for sites 1, 2, 3, 4, and 5, respectively. A significant change in morphology, root length, fresh weight, and dry weight in Allium cepa was observed under the exposure at different sites. Protein content of roots showed significant difference for samples at all sites while bulbs at sites S4 and S5 when compared to control. Antioxidant activity for root in terms of APX, GST, and POD showed significant changes at S4 and S5 and GR at site S5 and SOD at S1, S2, S3, S4, and S5. Similarly, bulbs showed significant changes at sites S4 and S5 for APX while at sites S3, S4, and S5 for POD and S2, S3, S4, and S5 for SOD and S5 for GR and GST. Genotoxicity study has shown induction of abnormalities at different stages of the cell cycle in Allium cepa root tips. The samples under exposure to radiation with maximum power density have shown maximum induction of oxidative stress and genotoxicity.

Large electronegativity differences between adjacent atomic sites activate and stabilize ZnIn2S4 for efficient photocatalytic overall water splitting

Photocatalytic overall water splitting into hydrogen and oxygen is desirable for long-term renewable, sustainable and clean fuel production on earth. Metal sulfides are considered as ideal hydrogen-evolved photocatalysts, but their component homogeneity and typical sulfur instability cause an inert oxygen production, which remains a huge obstacle to overall water-splitting. Here, a distortion-evoked cation-site oxygen doping of ZnIn2S4 (D-O-ZIS) creates significant electronegativity differences between adjacent atomic sites, with S1 sites being electron-rich and S2 sites being electron-deficient in the local structure of S1–S2–O sites. The strong charge redistribution character activates stable oxygen reactions at S2 sites and avoids the common issue of sulfur instability in metal sulfide photocatalysis, while S1 sites favor the adsorption/desorption of hydrogen. Consequently, an overall water-splitting reaction has been realized in D-O-ZIS with a remarkable solar-to-hydrogen conversion efficiency of 0.57%, accompanying a ~ 91% retention rate after 120 h photocatalytic test. In this work, we inspire an universal design from electronegativity differences perspective to activate and stabilize metal sulfide photocatalysts for efficient overall water-splitting.

Allosteric modulation of serotonin and dopamine transporters: New insights from computations and experiments

Human monoamine transporters (MATs) are critical to regulating monoaminergic neurotransmission by translocating their substrates from the synaptic space back into the presynaptic neurons. As such, their primary substrate binding site S1 has been targeted by a wide range of compounds for treating neuropsychiatric and neurodegenerative disorders including depression, ADHD, neuropathic pain, and anxiety disorders. We present here a comparative study of the structural dynamics and ligand-binding properties of two MATs, dopamine transporter (DAT) and serotonin transporter (SERT), with focus on the allosteric modulation of their transport function by drugs or substrates that consistently bind a secondary site S2, proposed to serve as an allosteric site. Our systematic analysis of the conformational space and dynamics of a dataset of 50 structures resolved for DAT and SERT in the presence of one or more ligands/drugs reveals the specific residues playing a consistent role in coordinating the small molecules bound to subsites S2–I and S2-II within S2, such as R476 and Y481 in dDAT and E494, P561, and F556 in hSERT. Further analysis reveals how DAT and SERT differ in their two principal modes of structural changes, PC1 and PC2. Notably, PC1 underlies the transition between outward- and inward-facing states of the transporters as well as their gating; whereas PC2 supports the rearrangements of TM helices near the S2 site. Finally, the examination of cross-correlations between structural elements lining the respective sites S1 and S2 point to the crucial role of coupled motions between TM6a and TM10. In particular, we note the involvement of hSERT residues F335 and G338, and E493-E494-T497 belonging to these two respective helices, in establishing the allosteric communication between S1 and S2. These results help understand the molecular basis of the action of drugs that bind to the S2 site of DAT or SERT. They also provide a basis for designing allosteric modulators that may provide better control of specific interactions and cellular pathways, rather than indiscriminately inhibiting the transporter by targeting its orthosteric site.

Water quality, heavy metal contamination and health risk assessment of surface water bodies of Mohammedia prefecture, Morocco

Research work on surface water bodies in Morocco has been in majority restricted to physicochemical and biological concentration. Hence, this study was conducted to address the existing research gap by evaluating heavy metal contamination and its associated risk assessment in surface water bodies, in Mohammedia prefecture, Morocco. A total of 22 water samples were evaluated regarding physicochemical factors and heavy metals. The parameters analyzed are pH, temperature (T), electrical conductivity (EC), total dissolved solids (TDS), calcium (Ca2+), Sodium (Na+), Potassium (K+), Ammonia (NH+), dissolved oxygen (DO), Sulphate (SO42−), nitrite (NO2−), nitrate (NO3−), phosphate (PO43−), total phosphate (TP), total kjeldahl nitrogen (TKN), cadmium (Cd), copper (Cu), Iron (Fe), lead (Pb), and zinc (Zn). Overall water quality (Ow) and status of contamination presented the water quality and pollution quantitatively. Carcinogenic and noncarcinogenic risks were estimated for health risk assessment. Ca2+ was the most abundant cation, and SO43− was the most abundant anion. Heavy metal concentrations were within permissible limits. Ow was good in terms of being suitable for parameters, i.e., <1 except for NH+. Which indicated water quality in the category of “highly polluted” >2.5. Pollution index (PI) indicated high pollution (14–74) at S3, S4, S5, and S6 sample points. In addition, Pb was a significant contributor to deteriorating water quality, with individual contributions ranging from 1 to 12 at sites S1, S2, and S3. For heavy metal hazards, i.e., adverse health effects, Hazard Quotient (HQ) (0.0002–0.01) was <1 for sample points, and Hazard Index (HI) (0.007–0.01) had a similar trend. They were inferring no significant non-carcinogenic health impact on its consumers. Carcinogenic risk (CR) was found to be within acceptable limits for CD, Cu, Pb, and Zn, i.e., 10−4 to 10−6. At points S2, S3, and S4, the carcinogenic index (CI) was above the acceptable limit, with values ranging from 1 × 10−3 to 7.9 × 10−3 attributed to Fe. Therefore, according to the findings of this research, the water quality is not suitable for direct consumption in its current state. Hence the study recommends treatment of surface water bodies prior to consumption.

Assessment of habitat and hydrological parameters of the lotic and lentic wetlands of the Sonitpur district, Assam, India

This paper represents the riparian zone and water parameters in twelve selected sampling sites of both lotic and lentic wetlands of Sonitpur district. The study has been carried out from January 2021 to February 2023. Data were collected representing all the four seasons of the year. Physical Characteristics viz; soil colour, soil moisture, soil texture, vegetation coverage, canopy coverage and litter depth were assessed during the survey period. Vegetation and canopy coverage of the riparian zone adjacent to the lotic wetlands were found to be the highest. Litter depth (3.1cm) was found to be recorded at a single sampling site S4 . Water quality assessment recorded that Water temperature was found to be one of the major factors having the most intense direct and indirect effect on the riverine system ranged from 4.85±0.02 to 27.60±0.10 in the lotic wetlands and between 11.15±0.02 to 27.44±0.05 in the lentic wetlands. The overall pH value ranged from 6.09±0.05 to 7.24±0.32 in the lotic wetlands and between 6.44±0.02 to 7.52±0.08 in the lentic wetlands which is a convenient zone. DO values ranged from 6.01±0.32 to 7.37±0.22 in the lotic wetlands and between 6.39±0.30 to 7.63±0.30 in the lentic wetlands. Maximum DO value was recorded in the monsoon period. Water velocity was observed to vary from 0.20±0.03 to 1.30±0.28 in the lotic wetlands. Highest water velocity was recorded during the monsoon period and lowest in the winter period.

Epilithic Diatom Assemblages and Indicators for the Assessment of Water Quality of Munzur Stream, Turkey

The epilithic diatoms of Munzur Stream, together with the chemistry and physical variables of the water, were examined in the samples taken annually from 3 stations on the creek between October 2016 and September 2017. A total of 69 diatom taxa were identified benthic habitat. Cocconeis placentula, Cymbella affinis, Cymbella excisiformis , Didymosphenia geminata, Gomphonema olivaceum, and Hannaea arcus became diatoms at all that reached significant relative abundance. Shannon-diversity (H’), species evenness (J’), species richness (S) in each station varied between stations and months. Regarding diversity (H), values ranged from 1.54 (in December, at S3) to 2.99 (in October, at S3). Evenness ranged from 0.09 to 0.22 at station S3 in September (at S1, in September). Evenness ranged from 0.09 at site S3 in September, to 0.22 at S1, in September. All stations and species were close to 1 value. Canonical correspondence analysis indicated that three environmental variables (TN,TP, PO4-3) significantly affected the distribution of epilithic diatom. The studied part of stream was characterized by the species susceptible to nutrients such as Didymosphenia geminata, Cymbella excisiformis and Hannaea arcus which are found in the regions located in high lands having advanced ecological status. The results of the present study highlighted the importance of diatoms as a bio-indicator for health condition of a stream.

Calibrating low-cost sensors using MERRA-2 reconstructed PM2.5 mass concentration as a proxy

Monitoring and mitigating air pollution is the most urgent need of society. In an ideal scenario, air quality must be mapped to the details of the geospatial grid to formulate area-specific roadmaps to mitigate air pollution. However, the heterogeneity of the existing air quality monitoring network in India must be addressed to improve the granularity of the data. Low-cost sensors (LCS) are a potential solution to overcome these challenges. However, their data quality remains an issue. Here, we present an alternative Machine Learning (ML)-based calibration approach for LCS using Modern-Era Retrospective Analysis for Research and Applications, version 2 (or MERRA-2) reconstructed surface-level PM2.5 data as a proxy to the reference mass concentrations at four monitoring sites in NCT-Delhi. LCS were calibrated with the co-located reference and MERRA-2 mass concentrations across sites, and their performance was evaluated. The reference and MERRA-2 reconstructed PM2.5 mass concentrations indicated a better agreement compared to the co-located reference and raw LCS measurements. The R2 values between the MERRA-2 calibrated LCS and reference mass measurements were 0.76 (R2LCS_uncalibrated = 0.68), 0.84 (R2LCS_uncalibrated = 0.76), 0.75 (R2LCS_uncalibrated = 0.65), and 0.78 (R2LCS_uncalibrated = 0.69) at sites S1, S2, S3, and S4, respectively. RMSE values reduced significantly post-calibration across sites. LCS calibrated with the reference monitors produced comparable results to MERRA-2 calibrated LCS across sites, which suggests that the calibration of LCS with MERRA-2 reconstructed PM2.5 is feasible. This new method of LCS calibration will promote citizen-science initiatives and allow regulators to gather high spatiotemporal air quality information.

Crystal structures of human immune protein FIBCD1 suggest an extended binding site compatible with recognition of pathogen-associated carbohydrate motifs

Fibrinogen C-domain containing-1 (FIBCD1) is an immune protein proposed to be involved in host recognition of chitin on the surface of pathogens. As FIBCD1 readily binds to acetylated molecules, we have determined the high-resolution crystal structures of a recombinant fragment of the FIBCD1 C-terminal domain complexed with small N-acetyl-containing ligands to determine the mode of recognition. All ligands bind at the conserved N-acetyl binding site (S1) with galactose and glucose-derived ligands rotated 180⁰ with respect to each other. One subunit of a native structure derived from protein expressed in mammalian CHO cells binds glycosylation from a neighbouring subunit, in an extended binding site. Across the various structures, the primary S1 binding pocket is occupied by N-acetyl-containing ligands or acetate, with N-acetyl, acetate or a sulfate ion in an adjacent pocket S1(2). Inhibition binding studies of N-acetylglucosamine oligomers, (GlcNAc)n, n=1,2,3,5,11, via ELISA along with Microscale Thermophoresis affinity assays indicate a strong preference of FIBCD1 for longer N-acetylchitooligosaccharides. Binding studies of mutant H396A, located beyond the S1(2) site, showed no significant difference to wildtype but K381L, within the S1(2) pocket, blocked binding to the model ligand acetylated bovine serum albumin suggesting that this pocket may have functional importance in FIBCD1 ligand binding. The binding studies, alongside structural definition of diverse N-acetyl monosaccharide binding in the primary S1 pocket and of additional, adjacent binding pockets, able to accommodate both carbohydrate and sulfate functional groups, suggests a versatility in FIBCD1 to recognise chitin oligomers and other pathogen-associated carbohydrate motifs across an extended surface.

Danshensu inhibits SARS-CoV-2 by targeting its main protease as a specific covalent inhibitor and discovery of bifunctional compounds eliciting antiviral and anti-inflammatory activity

The coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has posed a serious threat to human. Since there are still no effective treatment options against the new emerging variants of SARS-CoV-2, it is necessary to devote a continuous endeavor for more targeted drugs and the preparation for the next pandemic. Salvia miltiorrhiza and its active ingredients possess wide antiviral activities, including against SARS-CoV-2. Danshensu, as one of the most important active ingredients in Salvia miltiorrhiza, has been reported to inhibit the entry of SARS-CoV-2 into ACE2 (angiotensin-converting enzyme 2)-overexpressed HEK-293T cells and Vero-E6 cells. However, there is a paucity of information regarding its detailed target and mechanism against SARS-CoV-2. Here, we present Danshensu as a covalent inhibitor of 3-chymotrypsin-like protease (3CLpro) against SARS-CoV-2 by the time-dependent inhibition assay (TDI) and mass spectrometry analysis. Further molecular docking, site-directed mutagenesis, circular dichroism (CD) and fluorescence spectra revealed that Danshensu covalently binds to C145 of SARS-CoV-2 3CLpro, meanwhile forming the hydrogen bonds with S144, H163 and E166 in the S1 site. Structure-based optimization of Danshensu led to the discovery of the promising compounds with good inhibitory activity and microsomal stability in vitro. Due to Danshensu inhibiting lung inflammation in the mouse model, we found that Danshensu derivatives also showed better anti-inflammatory activity than Danshensu in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. Thus, our study provides not only the clue of the efficacy of Salvia miltiorrhiza against SARS-CoV-2, but also a detailed mechanistic insight into the covalent mode of action of Danshensu for design of covalent inhibitors against SARS-CoV-2 3CLpro, highlighting its potential as a bifunctional molecule with antivirus and anti-inflammation.

Perturbation of Na-ion distribution for enhancement of ionic conductivity to a practical level of over 1 mS·cm−1 in Na3ZnGaS4

Na-ion conducting solid-state electrolytes (SSEs) are increasingly garnering attention as potential alternatives to Li-ion conducting SSEs in all-solid-state batteries. In this study, we demonstrate that replacing a small fraction of S2− with I− in Na3ZnGaS4 perturbs Na ion distributions, leading to an increase in vacancy concentration and a decrease in Na-Na distance along the conduction channel. This dual effect of I-substitution results in a remarkable increase in the ionic conductivity (σion) of Na3-xZnGaS4-xIx, from ca. 10−3 mS·cm−1 in pristine Na3ZnGaS4 to 1.12 mS·cm−1 in Na2.9ZnGaS3.9I0.1. Importantly, this enhancement cannot be achieved through simple vacancy incorporation via aliovalent doping. The incorporation of less I− (x = 0.05) or more I− (x = 0.15 and 0.2) also leads to significant improvements in σion, highlighting the effectiveness of disturbing the Na site. Cl- or Br-doped Na3ZnGaS4 similarly enhances σion, but to a more limited extent, underscoring the pivotal role of dopant anion sizes in inducing Na disturbance. We provide evidence for the presence of iodides in a specific sulfur site (S3 site) and the consequential dispersion of Na ions to Na2 and Na3 sites through a combination of theoretical, crystallographic, and spectroscopic studies. Additionally, we demonstrate the electrochemical and moisture stability of Na2.9ZnGaS3.9I0.1. Finally, due to its electrochemical stability and high σion, we exemplify the practicality of Na2.9ZnGaS3.9I0.1 in all-solid-state batteries using Na2Sn ‖ TiS2 full cells.

Quantification of sedimentary organic carbon sources in a land–river–lake continuum combined with multi-fingerprint and un-mixing models

Identifying organic carbon (OC) sources in lake sediment is essential for elucidating biogeochemical cycling processes and effectively supporting watershed management. However, the complexity of sources as well as environments in the land–river–lake continuum makes it challenging to accurately identify OC sources. Accordingly, the current study utilized a systematic approach to identify and validate OC sources in a typical land–river–lake continuum. Two tracer groups (group 1: δ13C and δ15N; group 2: fluorescence index and biotic index, respectively (where C is carbon and N is nitrogen)) and one model (MixSIAR) were eventually selected from five tracer groups and two models to identify the OC sources in a land–river–lake continuum according to a consistency evaluation and virtual mixing test. The results showed that the distribution of OC sources in lake sediment was spatially heterogeneous. Closer to the lake center (from sampling site S1 to S3), the autochthonous contributions increased while the allochthonous contributions decreased. Downstream of the inlet river (site S1) was dominated by allochthonous contributions (78.6%), especially cropland (28.7% ± 0.5%, where ± indicates a standard deviation range) and urban land (30.5% ± 2.5%). From site S1 to S2, the allochthonous contribution decreased 11.4%. Autochthonous OC gradually became the major source closer to the lake center (site S3: phragmites: 48% ± 4.5%). This distribution of OC sources in the land–river–lake system was attributed to the mixing effect of the autochthonous sources, selective transport of sediment, and human activities. The current findings may aid in validating the ability of different tracers and models to identify OC sources in complex ecosystems and also provide a theoretical basis for watershed management.

CHRONOLOGICAL MODELING ON A CALIBRATION PLATEAU: IMPLICATIONS FOR THE EMERGENCE OF AGRICULTURE IN THE DUTCH WETLANDS

ABSTRACTShort-duration archeological sites situated entirely within plateaus in the radiocarbon calibration curve pose unique challenges for our understanding of past processes at regional and global scales. This paper aims to overcome these limitations by leveraging the specific characteristics of two depositional contexts, the Early Neolithic Swifterbant Culture sites S3 and S4, located in the Dutch wetlands. These sites are of exceptional significance as they provide the earliest conclusive evidence of crop cultivation and animal husbandry outside the expansion of Linearbandkeramik (LBK) farmers in north-western Europe. Here, we present a customized approach that combines radiocarbon dating and Bayesian modeling, predicated on vertical sequences of short-lived plant remains. Our innovative approach enables us to determine, at a fine scale, the temporal position and duration of the prominent archeological contexts at S3 and S4, and explore the chronological relationship between the two sites. Through our analysis, we propose a new chronology for the onset of Neolithization in the Dutch wetlands.

Metagenomic analysis reveals diverse microbial community and potential functional roles in Baner rivulet, India

BackgroundThe health index of any population is directly correlated with the water quality, which in turn depends upon physicochemical characteristics and the microbiome of that aquatic source. For maintaining the water quality, knowledge of microbial diversity is a must. The present investigation attempts to evaluate the microflora of Baner. Metagenomics has been proven to be the technique for examining the genetic diversity of unculturable microbiota without using traditional culturing techniques. The microbial profile of Baner is analyzed using metagenomics for the first time to the best of our knowledge. ResultsTo explore the microbial diversity of Baner, metagenomics analysis from 3 different sites was done. Data analysis identified 29 phyla, 62 classes, 131 orders, 268 families, and 741 genera. Proteobacteria was found to be the most abundant phylum in all the sampling sites, with the highest abundance at S3 sampling site (94%). Bacteroidetes phylum was found to be second abundant in S1 and S2 site, whereas Actinobacteria was second dominant in sampling site S3. Enterobacteriaceae family was dominant in site S1, whereas Comamonadaceae and Pseudomonadaceae was abundant in sites S2 and S3 respectively. The Baner possesses an abundant bacterial profile that holds great promise for developing bioremediation tactics against a variety of harmful substances. ConclusionBaner river’s metagenomic analysis offers the first insight into the microbial profile of this hilly stream. Proteobacteria was found to be the most abundant phylum in all the sampling sites indicating anthropogenic interference and sewage contamination. The highest abundance of proteobacteria at S3 reveals it to be the most polluted site, as it is the last sampling site downstream of the area under investigation, and falls after crossing the main city, so more human intervention and pollution were observed. Despite some pathogens, a rich profile of bacteria involved in bioremediation, xenobiotic degradation, and beneficial fish probiotics was observed, reflecting their potential applications for improving water quality and establishing a healthy aquaculture and fishery section.

Comparison of Soil Arthropod Diversity and Community Structure in Various Types of Land Cover in Malang Region, East Java, Indonesia

Land cover heterogeneity can affect the structure of biodiversity in the supplied niche, so it is necessary to know the taxa community. This study aimed to understand the effect of land cover variation on the diversity and community structure of soil arthropods. The types of habitats used include urban areas, agroforestry, gardens, and natural forests which are determined in the Malang Region, East Java, Indonesia. Hand sorting and hay bait traps were applied in this study to obtain a variety of arthropod soils and the Berlese-Tullgren funnel was used to extract them. As a result, there are 25 families from 15 orders collected based on their ecological roles. The abundance of Philoscidae in sites S1 and S2 (urban green space), Talitridae in site S6 (agroforestry), and Isotomidae in sites S3, S4, and S5 (highland mixed forest) was highest and dominant. Site S7 has the highest diversity (H' = 2.56; 1-D = 0.90; J' = 0.76) even though its family richness is lower. The site S3 counter-site had relatively high taxa richness (TR = 13), but low diversity (H' = 1.02; 1-D = 0.39; J' = 0.16). Based on clustering analysis and NMDS ordination, 3 classifications of habitat types were obtained, namely I (S6 &amp; S7), II (S3, S4 &amp; S5), and III (S1 &amp; S2). Mixed forest habitats contain a more complex diversity of soil arthropods, which can serve as a model for improving the fertility of disturbed ecosystems.

Psychrobacter species enrichment as potential microplastic degrader and the putative biodegradation mechanism in Shenzhen Bay sediment, China

Microplastic (MP) pollution has emerged as a pressing environmental concern due to its ubiquity and longevity. Biodegradation of MPs has garnered significant attention in combatting global MP contamination. This study focused on MPs within sediments near the sewage outlet of Shenzhen Bay. The objective was to elucidate the microbial communities in sediments with varying MPs, particularly those with high MP loads, and to identify microorganisms associated with MP degradation. The results revealed varying MP abundance, ranging from 211 to 4140 items kg–1 dry weight (d. w.), with the highest concentration observed near the outfall. Metagenomic analysis confirmed the enrichment of Psychrobacter species in sediments with high MP content. Psychrobacter accounted for ∼16.71% of the total bacterial community and 41.71% of hydrocarbon degrading bacteria at the S3 site, exhibiting a higher abundance than at other sampling sites. Psychrobacter contributed significantly to bacterial function at S3, as evidenced by the Kyoto Encyclopedia of Genes and Genomes pathway and enzyme analysis. Notably, 28 enzymes involved in MP biodegradation were identified, predominantly comprising oxidoreductases, hydrolases, transferases, ligases, lyases, and isomerases. We propose a putative mechanism for MP biodegradation, involving the breakdown of long-chain plastic polymers and subsequent oxidation of short-chain oligomers, ultimately leading to thorough mineralization.

Quantification of Heavy Metals and Chemical Stressors in Ground Water of Coal Mining Areas and Associated Human Health Risk

Acid mine drainage is one of the most obvious challenges in coal mining areas that is responsible for deteriorating soil and ground water quality of nearby communities thus posing serious human health risk. Objective: To quantify of heavy metals and chemical stressors in ground water and associated human health risk. Methods: Cross-sectional study with a combination of random sampling and Probability-Proportional-to-Size Sampling was used. Eight different sites were selected for water sample collection, and heavy metals were quantified. The analysis was carried out. Physicochemical properties of water were assessed using a portable photometer. Hematological parameters and antioxidants in the blood of study subjects were also measured. Results: Among the water samples, site S1 had the highest iron concentration at 0.354 ppm, exceeding the US limit of 0.3 ppm, with nickel being the next most abundant metal. Site S8 recorded the highest temperature at 36.4°C, while site S5 had the highest pH in the drinking water. The maximum electrical conductivity was found at S4 with 1387 s/m, and the total dissolved solvent parameter peaked at 1598 ppm in S8. Subjects exposed to acid mine drainage through water consumption displayed significant changes in antioxidant and blood parameters compared to the control group. In the exposed group, catalase (63.47), superoxide dismutase (33.26), and glutathione peroxidase (532.97) levels decreased, while malondialdehyde levels increased to 1.39. Conclusions: The physical and chemical properties of all water resources of mining areas were negatively altered due to heavy metals contamination thus poses a serious threat of oxidative stress in exposed subjects.

Herbal Compounds Dauricine and Isoliensinine Impede SARS-CoV-2 Viral Entry.

Targeting viral entry has been the focal point for the last 3 years due to the continued threat posed by SARS-CoV-2. SARS-CoV-2's entry is highly dependent on the interaction between the virus's Spike protein and host receptors. The virus's Spike protein is a key modulator of viral entry, allowing sequential cleavage of ACE2 at the S1/S2 and S2 sites, resulting in the amalgamation of membranes and subsequent entry of the virus. A Polybasic insertion (PRRAR) conveniently located at the S1/S2 site can also be cleaved by furin or by serine protease, TMPRSS2, at the cell surface. Since ACE2 and TMPRSS2 are conveniently located on the surface of host cells, targeting one or both receptors may inhibit receptor-ligand interaction. Here, we show that Dauricine and Isoliensinine, two commonly used herbal compounds, were capable of inhibiting SARS-CoV-2 viral entry by reducing Spike-ACE2 interaction but not suppressing TMPRSS2 protease activity. Further, our biological assays using pseudoviruses engineered to express Spike proteins of different variants revealed a reduction in infection rates following treatment with these compounds. The molecular modeling revealed an interconnection between R403 of Spike protein and both two compounds. Spike mutations at residue R403 are critical, and often utilized by ACE2 to gain cell access. Overall, our findings strongly suggest that Dauricine and Isoliensinine are effective in blocking Spike-ACE2 interaction and may serve as effective therapeutic agents for targeting SARS-CoV-2's viral entry.

Structure-guided discovery of aminopeptidase ERAP1 variants capable of processing antigens with novel PC anchor specificities.

Endoplasmic reticulum aminopeptidase 1 (ERAP1) belongs to the oxytocinase subfamily of M1 aminopeptidases (M1APs), which are a diverse family of metalloenzymes involved in a wide range of functions and have been implicated in various chronic and infectious diseases of humans. ERAP1 trims antigenic precursors into correct sizes (8-10 residues long) for Major Histocompatibility Complex (MHC) presentation, by a unique molecular ruler mechanism in which it makes concurrent bindings to substrate N- and C-termini. We have previously determined four crystal structures of ERAP1 C-terminal regulatory domain (termed ERAP1_C domain) in complex with peptide carboxyl (PC)-ends that carry various anchor residues, and identified a specificity subsite for recognizing the PC anchor side chain, denoted as the SC subsite to follow the conventional notations: S1 site for P1, S2 site for P2, and so forth. In this study, we report studies on structure-guided mutational and hydrolysis kinetics, and peptide trimming assays to further examine the functional roles of this SC subsite. Most strikingly, a point mutation V737R results in a change of substrate preference from a hydrophobic to a negatively charged PC anchor residue; the latter is presumed to be a poor substrate for WT ERAP1. These studies validate the crystallographic observations that this SC subsite is directly involved in binding and recognition of the substrate PC anchor and presents a potential target to modulate MHC-restricted immunopeptidomes.

Foliar architecture differentially restrains metal sequestration capacity in wheat grains (Triticum aestivum L.) grown in hyper-chloride-contaminated soils.

Anthropogenic activities, such as industrial wastewater and use of water softeners, cause hyper-accumulation of Cl- in water sources and soils. Currently, industries have no sustainable method to remove these Cl- ions from wastewater. This study was conducted to evaluate the integrative responses of wheat cultivated in five industrial effluent-affected areas (S2-S6) by investigating soil characters and bioaccumulation of metals in wheat plants and grains. The S4 site (near the second chloride outlet) exhibited a higher concentration of CO2, SO2, NO2, Cl-, Cd, Mn, Ni, Cr, and Zn. Soil from S6 (sewage wastewater downstream getting mixed with chloride-contaminated water) had a minimum level of nutrients (Na, K, and Ca), maximum metals (Cd, Fe, Pb, Mn), and reduction in plant biomass. In site S2 (sewage wastewater upstream of the chloride factory), a higher level of minerals and metals was noted in the roots. Maximum metals in grains occurred in S6 with higher organic osmolytes. The sequestration capacity of metals in leaves was also increased by alterations in anatomical traits. Results indicated that metals and hyper-Cl- concentration employed a negative influence on the plants because of poor soil quality, extremely damaged microstructures leading to reduced yield, poor grain quality, and excessive translocation from roots to wheat grains. These findings revealed that contaminated plants used as either green forage or hay are noxious to animals and if used as grain for feed or humans can lead to serious health hazards.