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Arsenic (As) is a highly toxic metal that interferes with plant growth and disrupts various biochemical and molecular processes in plants. In this study, the harmful effects of As on rice were mitigated using combined inoculation of a root endophyte Serendipita indica and an actinobacterium Zhihengliuella sp. ISTPL4. A randomized experiment was conducted, in which rice plants were grown under controlled conditions and As-stressed conditions. The control and treatment groups consisted of untreated and non-stressed plants (C1), treated and non-stressed plants (C2), stressed and untreated plants (T1), and stressed and treated plants (T2). Various phenotypic characteristics such as shoot length (SL), root length (RL), shoot fresh weight (SFW), root fresh weight (RFW), shoot dry weight (SDW), and root dry weight (RDW) and biochemical parameters such as chlorophyll content, protein content, and antioxidant enzymatic activities were evaluated. The activity of various antioxidant enzymes was increased in T2 followed by T1 plants. Furthermore, high concentrations of phytohormones such as ethylene (ET), gibberellic acid (GA), and cytokinin (CK) were found at 4.11 µmol mg-1, 2.53 µmol mg-1, and 3.62 µmol mg-1 of FW of plant, respectively. The results of AAS indicated an increased As accumulation in roots of T2 plants (131.5 mg kg-1) than in roots of T1 plants (120 mg kg-1). It showed that there was an increased As accumulation and sequestration in roots of microbial-treated plants (T2) than in uninoculated plants (T1). Our data suggest that this microbial combination can be used to reduce the toxic effects of As in plants by increasing the activity of antioxidant enzymes such as SOD, CAT, PAL, PPO and POD. Furthermore, rice plants can withstand As stress owing to the active synthesis of phytohormones in the presence of microbial combinations.
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Fungal-bacterial combinations have a significant role in increasing and improving plant health under various stress conditions. Metabolites secreted by fungi and bacteria play an important role in this process. Our study emphasizes the significance of secondary metabolites secreted by the fungus Serendipita indica alone and by an actinobacterium Zhihengliuella sp. ISTPL4 under normal growth conditions and arsenic (As) stress condition. Here, we evaluated the arsenic tolerance ability of S. indica alone and in combination with Z. sp. ISTPL4 under in vitro conditions. The growth of S. indica and Z. sp. ISTPL4 was measured in varying concentrations of arsenic and the effect of arsenic on spore size and morphology of S. indica was determined using confocal microscopy and scanning electron microscopy. The metabolomics study indicated that S. indica alone in normal growth conditions and under As stress released pentadecanoic acid, glycerol tricaprylate, L-proline and cyclo(L-prolyl-L-valine). Similarly, d-Ribose, 2-deoxy-bis(thioheptyl)-dithioacetal were secreted by a combination of S. indica and Z. sp. ISTPL4. Confocal studies revealed that spore size of S. indica decreased by 18% at 1.9 mM and by 15% when in combination with Z. sp. ISTPL4 at a 2.4 mM concentration of As. Arsenic above this concentration resulted in spore degeneration and hyphae fragmentation. Scanning electron microscopy (SEM) results indicated an increased spore size of S. indica in the presence of Z. sp. ISTPL4 (18 ± 0.75 µm) compared to S. indica alone (14 ± 0.24 µm) under normal growth conditions. Our study concluded that the suggested combination of microbial consortium can be used to increase sustainable agriculture by combating biotic as well as abiotic stress. This is because the metabolites released by the microbial combination display antifungal and antibacterial properties. The metabolites, besides evading stress, also confer other survival strategies. Therefore, the choice of consortia and combination partners is important and can help in developing strategies for coping with As stress.
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Rapid urbanization and globalization demand increasing agricultural productivity. Soil nutrient supply capacity is continuously decreasing due to soil erosion, degradation, salt deposition, undesired element, metal deposition, water scarcity, and an uneven nutrient delivery system. Rice cultivation requires a large amount of water which is becoming detrimental due to these activities. There is a need to increase its productivity. Microbial inoculants are becoming increasingly important in achieving sustainable agricultural production systems. The current study was conducted to investigate the interaction between the root endophytic fungus Serendipita indica (S. indica) and the actinobacterium Zhihengliuella sp. ISTPL4 (Z. sp. ISTPL4) and their synergistic effects on the growth of rice (Oryza sativa L). Both S. indica and Z. sp. ISTPL4 showed positive interactions. Growth of S. indica was observed at different days after Z. sp. ISTPL4 inoculation, and stimulated growth of S. indica was observed when Z. sp. ISTPL4 was inoculated at 5 dafi (days after fungal inoculation). Z. sp. ISTPL4 promoted the growth of S. indica as it increased spore germination. Furthermore, confocal and scanning electron microscopy (SEM) analyses showed a 27% increase in the spore size of S. indica in the presence of Z. sp. ISTPL4. In a liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis increased production of alanine and glutamic acid was observed in their sequential co-culture as compared with individual cultures. Sequential inoculation of S. indica and Z. sp. ISTPL4 significantly increased the biochemical and physical characteristics of rice as compared with their individual inoculum. Biochemical parameters such as chlorophyll content, total soluble sugar, and flavonoid content in the rice increased by up to 57%, 47%, and 39%, respectively, in the presence of the combined inoculum of S. indica and Z. sp. ISTPL4. This will be the first study, to the best of our knowledge, which shows the fungus and actinobacterium interaction and their synergistic roles in the growth promotion of rice. Furthermore, this novel combination can also be used to boost the growth of other crops to increase the agricultural yield.
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Aspergillus fumigatus is an opportunistic pathogen that primarily affects the lungs and frequently elicits an allergic immune response in human hosts via inhalation of its airborne asexual spores (conidia). In immunocompromised individuals, the conidia of this fungus can germinate in the lung and result in severe systemic infections characterised by widespread tissue and organ damage. Conversely, in healthy hosts, the innate immune system is instrumental in eliminating the conidia and preventing disease progression. As with numerous other pathogenic fungi, A. fumigatus possesses a set of virulence factors that facilitate its infective mechanism and the circumvention of immune defences in susceptible hosts. The intrinsic capacity of A. fumigatus to form complex 3D-structured biofilms, both on biotic and abiotic surfaces, represents a key determinant of its evasion of the host immune system and resistance to antifungal drugs. This review delineates the pivotal role of A. fumigatus biofilm structure and function as a significant virulence factor in pathogenic infections, such as aspergilloma and invasive pulmonary aspergillosis (IPA). Additionally, we discuss the importance for the development of novel antifungal drugs as drug-resistant strains continue to evolve. Furthermore, co-infections of A. fumigatus with other nosocomial pathogens have a substantial impact on patient's health outcomes. In this context, we provide a brief overview of COVID-19-associated pulmonary aspergillosis (CAPA), a recently documented condition that has gained attention due to its associated high degree of severity.
Subject(s)
Aspergillosis , COVID-19 , Pulmonary Aspergillosis , Humans , Aspergillus fumigatus , Aspergillosis/microbiology , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Virulence , Virulence Factors , Immunity , BiofilmsABSTRACT
Synthetic dyes and colourants have been the mainstay of the pigment industry for decades. Researchers are eager to find a more environment friendly and non-toxic substitute because these synthetic dyes have a negative impact on the environment and people's health. Microbial pigments might be an alternative to synthetic pigments. Microbial pigments are categorized as secondary metabolites and are mainly produced due to impaired metabolism under stressful conditions. These pigments have vibrant shades and possess nutritional and therapeutic properties compared to synthetic pigment. Microbial pigments are now widely used within the pharmaceuticals, food, paints, and textile industries. The pharmaceutical industries currently use bacterial pigments as a medicine alternative for cancer and many other bacterial infections. Their growing popularity is a result of their low cost, biodegradable, non-carcinogenic, and environmentally beneficial attributes. This audit article has made an effort to take an in-depth look into the existing uses of bacterial pigments in the food and pharmaceutical industries and project their potential future applications.
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Objective: There is limited evidence on the development of mobile health (mHealth) interventions for smokeless tobacco (SLT) cessation, despite its widespread use in South Asia. This formative qualitative study explored the perceptions of tobacco users and healthcare providers (HCPs) regarding developing a mHealth intervention for SLT cessation. Methods: This was a qualitative study using in-depth interviews (IDIs) with tobacco users (n = 26) and primary care physicians (PCPs) (n = 5) and focus group discussions (FGDs) with counsellors (n = 2) in four urban primary health centres (UPHCs) in Berhampur, Odisha from February to March 2020. The data were coded and analysed by two researchers using a framework analysis method. The discussion guides and initial codes were developed based on the Transtheoretical Model (TTM) of behaviour change. Results: The results were elaborated under four themes: (1) Current scenario of SLT use; (2) Barriers and facilitators for quitting SLT; (3) Barriers and facilitators for mHealth counselling; and (4) Design and delivery of the proposed intervention. SLT use was prevalent in the community regardless of sociodemographic factors. Peer factors accounted for both tobacco consumption as well as considering cessation. Participants considered mobile message counselling helpful and acceptable. Not having a mobile phone and illiteracy were identified as barriers while ease of access and rising popularity of social media applications were considered facilitators to the use of mHealth for quitting tobacco. Participants preferred messages that were pictorial, short and simple, in the local language, and tailored to individual's needs. Conclusions: This is the first study that provides evidence within the Indian context that the text messaging platform may be used for delivering an SLT cessation intervention. The integration of a theoretical basis and research findings from target users can guide future intervention development.
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BACKGROUND: The Coronavirus Disease 2019 (COVID-19) has severely challenged healthcare delivery systems worldwide. Healthcare Workers were unable to assess and manage the cases due to limited knowledge of treating the virus and inadequate infrastructure. Digital interventions played a crucial role in the training of healthcare workers to get through the pandemic. Project Extension for Community Healthcare Outcomes (ECHO) initiated the COVID-ECHO telementoring program for strengthening the knowledge and skills of healthcare workers. The study aimed at assessing the effects of the ECHO telementoring model in the capacity building of healthcare workers in the context of COVID-19 in India. METHOD: We adopted a mixed-method approach with a parallel combination design. A quantitative survey was used to measure changes in the knowledge and self-efficacy among doctors and nurses. In-depth Interviews were used for qualitative exploration of perceptions and experiences of all the study participants. Student t-test and ANOVA were used to assess significant differences between mean scores across participant characteristics for different themes. Statistical significance was set at p < 0.05. In-depth Interviews were analyzed using Framework Analysis. The evaluation followed the first five levels of Moore's model. RESULTS: The results highlighted the strengthening of knowledge and skills of healthcare workers in the assessment and management of COVID-19 after the ECHO training. Learning and performance ratings were high as 96% reported an increase in knowledge and 98% were able to apply it in their clinical practices. The key challenges identified were technical issues like internet connectivity and lack of interaction due to limited visual connection. The hybrid sessions, use of video camera, feedback mechanism, and inclusion of Continuing Medical Education were recommended by participants to improve the model. CONCLUSIONS: The findings of this study are an important addition to the pre-existing literature supporting the replicability of the ECHO model in the upskilling of healthcare professionals working in underserved and remote areas, not only in the context of COVID-19 but also in other public health domains. To enhance the effectiveness of this ECHO model, the study findings may be used to refine the model and improve the areas of concern.
Subject(s)
COVID-19 , COVID-19/epidemiology , Delivery of Health Care , Education, Medical, Continuing/methods , Health Personnel/education , Humans , PandemicsABSTRACT
Soil is an integral part of the ecosystem because it serves as a habitat for various microorganisms and lays the foundation for supporting plant growth and development. Therefore, factors such as increased anthropogenic activities hand by hand with other natural processes that harm the ecosystem may eventually lead to a decline in soil quality and fertility, hindering the growth of plants and soil microbial communities. Given the current global scenario of increasing human intervention, it is essential to find effective measures and reliable technologies to restore soil quality. Biochar is an emerging soil ameliorant employed for soil health restoration and is primarily generated through the anoxygenic pyrolysis of biomass. The biochar application in soil remediation may be beneficial due to biochar's unique physicochemical properties, including high carbon and metal fixation abilities. In addition, biochar possesses abilities to reduce the plant's environmental stress injuries. This review briefly overviewed the ingredients and mechanism of biochar productions. We then emphatically reviewed the advances in biochar applications in soil bioremediation, soil microflora growth stimulation, and the alleviation of various biotic and abiotic stresses in plants.
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Anthropogenic activities have drastically affected the environment, leading to increased waste accumulation in atmospheric bodies, including water. Wastewater treatment is an energy-consuming process and typically requires thousands of kilowatt hours of energy. This enormous energy demand can be fulfilled by utilizing the microbial electrolysis route to breakdown organic pollutants in wastewater which produces clean water and biohydrogen as a by-product of the reaction. Microalgae are the promising microorganism for the biohydrogen production, and it has been investigated that the interaction between microalgae and bacteria can be used to boost the yield of biohydrogen. Consortium of algae and bacteria resulting around 50-60% more biohydrogen production compared to the biohydrogen production of algae and bacteria separately. This review summarises the recent development in different microalgae-bacteria granular consortium systems successfully employed for biohydrogen generation. We also discuss the limitations in biohydrogen production and factors affecting its production from wastewater.
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Microalgae , Water Purification , Bacteria/metabolism , Biofuels , Fermentation , Hydrogen/metabolism , Microalgae/metabolism , Wastewater , WaterABSTRACT
Most of the discarded waste material paves their way to the utmost common dumping grounds, Landfills. Despite their widespread use, the landfill microbiomes are still not well characterized. Metagenomics approach provides insight into the identification of operational parameters influencing the microbiome composition and their biodegradation competencies. The metagenomic DNA was prepared to explore taxonomical community structure, phylogenetic relationships, and functional profile at the same time. A total of 100,021,052 high-quality filtered reads were acquired with a GC abundance of 62.59%. Taxonomical abundance revealed the dominance of phylum Proteobacteria and genes involved in biomolecules metabolism, aromatic compound degradation, stress tolerance, xenobiotic biodegradation etc. were revealed functionally. The intricate heterogeneous environment of landfill revealed well flourished biogeochemical metabolic profiles including nitrogen metabolism. This is the first study for the generated metagenome of Ghazipur landfill and the obtained results propose that microbial communities in landfill settings are far more intricate than expected. It remain mostly unexplored which demands the usage of multiple platforms for a better understanding.
Subject(s)
Metagenomics , Microbiota , Metagenome , Microbiota/genetics , Phylogeny , Waste Disposal FacilitiesABSTRACT
INTRODUCTION: Despite widespread use of smokeless tobacco products by people within the Indian subcontinent, there is little awareness among Indians of its health hazards when compared with smoked tobacco. We hypothesise that mobile phone counselling will be feasible and effective for smokeless tobacco cessation intervention in India. This paper presents the protocol of the development and conduct of an exploratory trial before progression to a full randomised controlled trial. METHODS AND ANALYSIS: An exploratory randomised controlled trial will be conducted in urban primary health centres in the state of Odisha, India. A total of 250 smokeless tobacco users will be recruited to the study (125 in each arm). Participants in the intervention arm will receive routine care together with a face-to-face counselling intervention followed by advice and reminder mobile messages. The control arm will receive routine care, delivered by a primary care physician based on 'Ask' and 'Advice'. All participants will be followed up for 3 months from the first counselling session. The primary outcome of this trial is to assess the feasibility to carry out a full randomised controlled trial. ETHICS AND DISSEMINATION: Ethical approvals were obtained from the Institutional Ethics Committee of Public Health Foundation of India, Health Ministry's Screening Committee, Odisha State Ethics Board and also from University College London Research Ethics Committee, UK. The study findings will be published in a peer-reviewed scientific journal. TRIAL REGISTRATION NUMBER: CTRI/2019/05/019484.
Subject(s)
Cell Phone , Tobacco Use Cessation , Counseling , Humans , Primary Health Care , Public Health , Randomized Controlled Trials as TopicABSTRACT
PURPOSE: The ubiquitous presence and rampant spread of antibiotic resistant strains of Shigella spp is a major public health concern. Therefore, monitoring the trends of antimicrobial resistance in them is essential. METHODS: A total of 15440 stool samples were inoculated on MacConkey agar, lysine deoxycholate agar and Selenite F enrichment broth from 2001 to 2015.Out of 491 shigellae isolated, 250 isolates were recovered from our culture collection. Antimicrobial susceptibility was performed by Kirby Bauer disc diffusion method, E-test and phenotypic resistance screening for ESBL and AmpC production was performed. For the detection of beta-lactamase genes, PCR for blaTEM, blaSHV, blaOXA, blaCTX-M-15, CMY-2 and mphA PCR in isolates with decreased susceptibility to azithromycin(DSA) was performed. RESULTS: S. flexneri (n â= â173) was most common, followed by S.dysenteriae (n â= â24), S.sonnei (n â= â23), S.boydii (n â= â10) and Non agglutinating Shigella (NAG, n â= â20). A see-saw pattern in the prevalence of S. flexneri and S. dysenteriae and rising prevalence of S. sonnei and NAG was seen. Majority (77%) of the isolates had MICs >4 âmg/L for ciprofloxacin and >50% had high MIC90 (12 âmg/L) for ceftriaxone and cefepime (8 âmg/L). Nearly 20% of S.flexneri were resistant to third generation cephalosporin by disc diffusion and 33.7% had MIC ≥1 âµg/mL. Among the ceftriaxone resistant isolates (n â= â29) the blaTEM beta-lactamase resistance gene was seen in all, blaCTX-M-15 in 37%, blaCMY-2 in 45.6% and blaOXA in 52%. The first report of DSA at our institute was in 2001 (n â= â1, 2.5%) which increased to 35.1% (n â= â40) in 2011-15. The isolates with DSA included S. flexneri (n â= â40), S. boydii (n â= â4) and S. sonnei (n â= â1) and plasmid mediated resistance to azithromycin by mphA gene was detected in 19 out of 40 isolates of S. flexneri. CONCLUSION: Global emergence of resistance Shigella is a matter of concern and calls for systematic monitoring and periodic updates of countrywide and local antibiogram.
Subject(s)
Dysentery, Bacillary , Shigella , Agar , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Azithromycin , Ceftriaxone , Drug Resistance, Bacterial/genetics , Dysentery, Bacillary/epidemiology , Humans , Microbial Sensitivity Tests , beta-Lactamases/geneticsABSTRACT
The ability of microalgae to grow in a broad spectrum of wastewaters manifests great potentials for removing contaminants from effluents of industries and urban areas. Since the post-treatment microalgae biomass is also a significant source of high-value products, microalgae-based wastewater treatment is an economical and sustainable solution to wastewater management. Adding more value, the integration of microalgae with living/non-living materials looks more promising. Microalgae-based treatment technology has certain limitations like high operational costs, problematic harvesting, large land requirements, and hindrance in photosynthesis due to turbid wastewater. These challenges need to be essentially addressed to achieve enhanced wastewater remediation. This review has highlighted the potential applications of microalgae in contaminant removal from wastewaters, simultaneous resource recovery, efficient microalgae-based hybrid systems along with bottlenecks and prospects. This state-of-the-art article will edify the role of microalgae in wastewater remediation, biomass valorization for bio-based products, and present numerous possibilities in strengthening the circular bioeconomy.
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Microalgae , Water Purification , Biofuels , Biomass , Photosynthesis , WastewaterABSTRACT
Agroforestry, an integration of farming system with woody perennials leads to the generation of potential agroforestry residues. The conventional treatment of agroforestry waste includes landfilling, thermal management, and decomposition which is accompanied with their own share of disadvantages. The ample amount of residues and products needs effective management to reap the economic and environmental benefits. The channel of waste collection, transportation, and recycle or valorization into products like biofuel, fertilizers, biochar, industrial chemicals is essential to maintain a circular sustainable bioeconomy. Global market value of biowaste to bioenergy (BtB) technology is roughly US $25.32 billion and is projected to enhance to US $40 billion by 2023. Employment of an appropriate pretreatment technology such as fermentation, hydrolysis, gasification etc. is going to elevate the degree of valorization along with surpassing the mobilization barrier. The sustainability assessment of the management process can be achieved with multiple models including technoeconomic analysis, life cycle assessment and multi criteria approach which are dependent on both hard and soft indices. Additionally, the loopholes of the agroforestry sectors would be managed by the introduction of appropriate policies which are undertaken globally by the Orlando and Lugo declarations, food and agriculture organization, Millennium Development Goals, Global Research Alliance and Guidelines for Sustainable Agriculture and Rural Development. The present review envisaged the agroforestry waste management strategy and its sustainability assessment primarily based upon Social, Economic and Environmental parameters without tormenting the future generations.
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Forestry , Waste Management , Agriculture , Biofuels , RecyclingABSTRACT
The development of potent antibiotic alternatives with rapid bactericidal properties is of great importance in addressing the current antibiotic crisis. One representative example is the topical delivery of predatory bacteria to treat ocular bacterial infections. However, there is a lack of suitable methods for the delivery of predatory bacteria into ocular tissue. This work introduces cryomicroneedles (cryoMN) for the ocular delivery of predatory Bdellovibrio bacteriovorus (B. bacteriovorus) bacteria. The cryoMN patches are prepared by freezing B. bacteriovorus containing a cryoprotectant medium in a microneedle template. The viability of B. bacteriovorus in cryoMNs remains above 80% as found in long-term storage studies, and they successfully impede the growth of gram-negative bacteria in vitro or in a rodent eye infection model. The infection is significantly relieved by nearly six times through 2.5 days of treatment without substantial effects on the cornea thickness and morphology. This approach represents the safe and efficient delivery of new class of antimicrobial armamentarium to otherwise impermeable ocular surface and opens up new avenues for the treatment of ocular surface disorders.
Subject(s)
Bdellovibrio bacteriovorus/physiology , Eye Infections/microbiology , Injections, Intraocular/methods , Administration, Topical , Animals , Bdellovibrio bacteriovorus/growth & development , Cornea/anatomy & histology , Cornea/physiology , Disease Models, Animal , Eye Infections/diagnostic imaging , Eye Infections/therapy , Gram-Negative Bacteria/physiology , Injections, Intraocular/instrumentation , Male , Mice , Mice, Inbred C57BL , Needles , Tomography, Optical CoherenceABSTRACT
The current work proposed the application of methylammonium lead iodide (MAPbI3) perovskite microrods toward photo resistor switches. A metal-semiconductor-metal (MSM) configuration with a structure of silver-MAPbI3(rods)-silver (Ag/MAPbI3/Ag) based photo-resistor was fabricated. The MAPbI3 microrods were prepared by adopting a facile low-temperature solution process, and then an independent MAPbI3 microrod was employed to the two-terminal device. The morphological and elemental compositional studies of the fabricated MAPbI3 microrods were performed using FESEM and EDS, respectively. The voltage-dependent electrical behavior and electronic conduction mechanisms of the fabricated photo-resistors were studied using current-voltage (I-V) characteristics. Different conduction mechanisms were observed at different voltage ranges in dark and under illumination. In dark conditions, the conduction behavior was dominated by typical trap-controlled charge transport mechanisms within the investigated voltage range. However, under illumination, the carrier transport is dominated by the current photogenerated mechanism. This study could extend the promising application of perovskite microrods in photo-induced resistor switches and beyond.
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Filamentous cyanobacteria, Jacksonvillea sp. ISTCYN1 was isolated from agriculture field and cultured in BG-11 medium. This study, report the genome sequence of cyanobacteria Jacksonvillea thatto the best of our knowledgeis the firstgenome sequenceof thisgenus. The 5.7 MB draft genome sequence of this cyanobacterium contains 5134 protein-coding genes. The phylogenetic tree was constructed based on genome and Desertifilum sp. IPPAS B-1220 validated the closest relationship with Jacksonvillea sp. ISTCYN1. The growth of strain ISTCYN1 has been reported in the presence of different types of plastic when used as a sole carbon source. SEM analysis revealed biofilm formation by cyanobacterial strain ISTCYN1 on the surface of high and low-density polyethylene and polypropylene. In the presence of these plastics, EPS production has also been reported by this strain. Whole genome sequence analysis reveals the presence of many genes involved in biofilm formation. The presence of key enzymes responsible for plastic degradation laccase, esterase, lipase, thioesterase, and peroxidase have been predicted in the genome analysis. Genome analysis also provides insight into the genes involved in biotin biosynthetic pathways. Furthermore, the presence of many selenoproteins reveals the selenium acquisition by this cyanobacterium.
Subject(s)
Cyanobacteria , Genome, Bacterial , Base Sequence , Biosynthetic Pathways , Cyanobacteria/genetics , Genome, Bacterial/genetics , PhylogenyABSTRACT
Perovskite solar cells (PSCs) expressed great potentials for offering a feasible alternative to conventional photovoltaic technologies. 2D/3D hybrid PSCs, where a 2D capping layer is used over the 3D film to avoid the instability issues associated with perovskite film, have been reported with improved stabilities and high power conversion efficiencies (PCE). However, the profound analysis of the PSCs with prolonged operational lifetime still needs to be described further. Heading towards efficient and long-life PSCs, in-depth insight into the complicated degradation processes and charge dynamics occurring at PSCs' interfaces is vital. In particular, the Au/HTM/perovskite interface got a substantial consideration due to the quest for better charge transfer; and this interface is debatably the trickiest to explain and analyze. In this study, multiple characterization techniques were put together to understand thoroughly the processes that occur at the Au/HTM/perovskite interface. Inquest analysis using current-voltage (I-V), electric field induced second harmonic generation (EFISHG), and impedance spectroscopy (IS) was performed. These techniques showed that the degradation at the Au/HTM/perovskite interface significantly contribute to the increase of charge accumulation and change in impedance value of the PSCs, hence resulting in efficiency fading. The 3D and 2D/3D hybrid cells, with PCEs of 18.87% and 20.21%, respectively, were used in this study, and the analysis was performed over the aging time of 5000 h. Our findings propose that the Au/HTM/perovskite interface engineering is exclusively essential for attaining a reliable performance of the PSCs and provides a new perspective towards the stability enhancement for the perovskite-based future emerging photovoltaic technology.
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Synthetic dyes pose a large threat to the environment and consequently to human health. Various dyes are used in textile, cosmetics, and pharmaceutical industries, and are released into the environment without any treatment, thus adversely affecting both the environment and neighboring human populations. Several existing physical and chemical methods for dye degradation are effective but have many drawbacks. Biological methods over the years have gained importance in the decolorization and degradation of dye and have also overcome the disadvantages of physiochemical methods. Furthermore, biological methods are eco-friendly and lead to complete decolorization. The mechanism of decolorization and degradation by several bacterial enzymes are discussed in detail. For the identification of ecologically sustainable strains and their application at the field level, we have focused on bioaugmentation aspects. Furthermore, in silico studies such as molecular docking of bacterial enzymes with dyes can give a new insight into biological studies and provide an easy way to understand the interaction at the molecular level. This review mainly focuses on an integrative approach and its importance for the effective treatment and decolorization of dyes.
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The environment of a high altitude brackish water lake presents an unprecedented reservoir for the microbial community with adaptability towards surviving stressful conditions. Pangong lake is a high altitude brackish water lake of the Himalayas situated in the eastern part of Ladakh (Indian Tibet), at the height of 4250 m above the sea level. Shotgun metagenomics sequencing of Pangong Lake sediments was performed to examine the taxonomic diversity and functional adaptations of the resident psychrophilic and psychrotolerant microbial communities of the lake (September; a temperature of ±10 °C). Proteobacteria was the most prominent phylum, and Methylophaga, Halomonas, and Marinobacter were mainly abundant at the genus level. Enzyme pathways responsible for methane metabolism, nitrogen metabolism, sulfur reduction, benzoate, and xylene degradation appeared to be complete in the metagenomic dataset. Stress response genes responsible for adaption to pH, cold, salt tolerance, osmotic stress, and oxidative stress were also found in abundance in the metagenome. We compared the Pangong lake metagenome sample to sediments and water samples from three different aquatic habitats, namely saline lake, freshwater lakes and marine ecosystem using MG-RAST server against RefSeq and Subsystem databases. The Pangong lake microbial community contains six unique genera. Regression analysis using metagenome samples suggested that Pangong lake was most closely related to the Trophic South Pacific Ocean (R2 = 0.971) and Socompa lake ecosystem (R2 = 0.991) at phylum and functional level II, respectively. Our study signifies that the functional metabolic potentiality of Pangong lake is strongly influenced by the taxonomic structure and environmental conditions. We are reporting the metagenome of the sediment sample of the Pangong lake, which unveils the microbial diversity and their functional potential.