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1.
J Med Virol ; 96(7): e29308, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39007405

RESUMO

Respiratory syncytial virus (RSV) remains the primary cause of lower respiratory tract infections, particularly in infants and the elderly. In this study, we employed reverse genetics to generate a chimeric influenza virus expressing neuraminidase-3F protein conjugate with three repeats of the RSV F protein protective epitope inserted into the NA gene of A/California/7/2009 ca (CA/AA ca), resulting in rFlu/RSV/NA-3F (hereafter, rFRN3). The expression of NA-3F protein was confirmed by Western blotting. The morphology and temperature-sensitive phenotype of rFRN3 were similar to CA/AA ca. Its immunogenicity and protective efficiency were evaluated in BALB/c mice and cotton rats. Intranasal administration of rFRN3 elicited robust humoral, cellular, and to some extent, mucosal immune responses. Compared to controls, rFRN3 protected animals from RSV infection, attenuated lung injury, and reduced viral titers in the nose and lungs post-RSV challenge. These results demonstrate that rFRN3 can trigger RSV-specific immune responses and thus exhibits potent protective efficacy. The "dual vaccine" approach of a cold-adapted influenza vector RSV vaccine will improve the prophylaxis of influenza and RSV infection. rFRN3 thus warrants further clinical investigations as a candidate RSV vaccine.


Assuntos
Anticorpos Antivirais , Vetores Genéticos , Camundongos Endogâmicos BALB C , Infecções por Vírus Respiratório Sincicial , Vacinas contra Vírus Sincicial Respiratório , Sigmodontinae , Animais , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Infecções por Vírus Respiratório Sincicial/imunologia , Vacinas contra Vírus Sincicial Respiratório/imunologia , Vacinas contra Vírus Sincicial Respiratório/administração & dosagem , Vacinas contra Vírus Sincicial Respiratório/genética , Feminino , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Camundongos , Vetores Genéticos/genética , Vetores Genéticos/imunologia , Pulmão/virologia , Pulmão/imunologia , Pulmão/patologia , Administração Intranasal , Temperatura Baixa , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Modelos Animais de Doenças , Proteínas Virais de Fusão/imunologia , Proteínas Virais de Fusão/genética , Imunidade nas Mucosas , Eficácia de Vacinas , Carga Viral
2.
Arch Microbiol ; 206(7): 307, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884653

RESUMO

Xylanase is the most important hydrolase in the xylan hydrolase system, the main function of which is ß-1,4-endo-xylanase, which randomly cleaves xylans to xylo-oligosaccharides and xylose. Xylanase has wide ranging of applications, but there remains little research on the cold-adapted enzymes required in some low-temperature industries. Glycoside hydrolase family 8 (GH8) xylanases have been reported to have cold-adapted enzyme activity. In this study, the xylanase gene dgeoxyn was excavated from Deinococcus geothermalis through sequence alignment. The recombinant xylanase DgeoXyn encodes 403 amino acids with a theoretical molecular weight of 45.39 kDa. Structural analysis showed that DgeoXyn has a (α/α)6-barrel fold structure typical of GH8 xylanase. At the same time, it has strict substrate specificity, is only active against xylan, and its hydrolysis products include xylobiose, xylotrinose, xytetranose, xylenanose, and a small amount of xylose. DgeoXyn is most active at 70 â„ƒ and pH 6.0. It is very stable at 10, 20, and 30 â„ƒ, retaining more than 80% of its maximum enzyme activity. The enzyme activity of DgeoXyn increased by 10% after the addition of Mn2+ and decreased by 80% after the addition of Cu2+. The Km and Vmax of dgeox were 42 mg/ml and 20,000 U/mg, respectively, at a temperature of 70 â„ƒ and pH of 6.0 using 10 mg/ml beechwood xylan as the substrate. This research on DgeoXyn will provide a theoretical basis for the development and application of low-temperature xylanase.


Assuntos
Deinococcus , Endo-1,4-beta-Xilanases , Estabilidade Enzimática , Xilanos , Deinococcus/enzimologia , Deinococcus/genética , Especificidade por Substrato , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/metabolismo , Xilanos/metabolismo , Temperatura Baixa , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Concentração de Íons de Hidrogênio , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Glicosídeo Hidrolases/química , Sequência de Aminoácidos , Hidrólise , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Alinhamento de Sequência , Clonagem Molecular , Cinética , Peso Molecular , Dissacarídeos
3.
Artigo em Inglês | MEDLINE | ID: mdl-38896461

RESUMO

A Gram-stain-positive, rod-shaped bacterium, designated as HLT2-17T, was isolated from soil sample taken from the Hailuogou glacier in Sichuan province, PR China. Strain HLT2-17T was capable of growing at 4-25°C and in NaCl concentrations ranging from 0 to 2% (w/v). The highest level of 16S rRNA gene sequence similarity was observed with Pengzhenrongella phosphoraccumulans M0-14T (98.3 %) and Pengzhenrongella sicca LRZ-2T (98.2 %). The average nucleotide identity and digital DNA-DNA hybridization values between strain HLT2-17T and its closest relatives, P. phosphoraccumulans M0-14T and P. sicca LRZ-2T, were 80.0-84.0 % and 23.3-27.7 %, respectively. Phylogenomic analysis indicated that strain HLT2-17T clustered together with strains P. phosphoraccumulans M0-14T and P. sicca LRZ-2T. Strain HLT2-17T contained C16 : 0 and anteiso-C15 : 0 as the major fatty acids, and MK-9(H4) as the menaquinone. Therefore, based on a polyphasic approach, we propose that strain HLT2-17T (=CGMCC 1.11116T= NBRC 110443T) represents a novel species of the genus Pengzhenrongella and suggest the name Pengzhenrongella frigida sp. nov.


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Camada de Gelo , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Microbiologia do Solo , Vitamina K 2 , RNA Ribossômico 16S/genética , China , Ácidos Graxos/química , DNA Bacteriano/genética , Vitamina K 2/análogos & derivados , Vitamina K 2/química , Vitamina K 2/análise , Camada de Gelo/microbiologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-38845151

RESUMO

Cellulases play an important role in the bioconversion of lignocellulose. Microorganisms found in extreme environments are a potentially rich source of cellulases with unique properties. Due to the uniqueness of the environment, the abundant microbial resources in the Qinghai-Tibet Plateau (QTP) are worth being explored. The aim of this study was to isolate and characterize an acidic, mesophilic cellulase-producing microorganism from QTP. Moreover, the fermentation conditions for cellulase production were optimized for future application of cellulase in the development of lignocellulose biomass. A novel cellulase-producing strain, Penicillium oxalicum XC10, was isolated from the soil of QTP. The cellulase produced by XC10 was a mesophilic cellulase that exhibited good acid resistance and some cold-adaptation properties, with maximum activity at pH 4.0 and 40°C. Cellulase activity was significantly enhanced by Na+ (p < 0.05) and inhibited by Mg2+, Ca2+, Cu2+, and Fe3+ (p < 0.05). After optimization, maximum cellulase activity (8.56 U/mL) was increased nearly 10-fold. Optimal fermentation conditions included an inoculum size of 3% (v/v) in a mixture of corn straw (40 g/L), peptone (5 g/L), and Mg2+ (4 g/L), at pH 4.0, 33°C, and shaking at 200 rpm. The specific properties of the P. oxalicum XC10 cellulase suggest the enzyme may serve as an excellent candidate for the bioconversion and utilization of lignocellulose biomass generated as agricultural and food-processing wastes.

5.
Mar Drugs ; 22(2)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38393032

RESUMO

Biofilm is accountable for nosocomial infections and chronic illness, making it a serious economic and public health problem. Staphylococcus epidermidis, thanks to its ability to form biofilm and colonize biomaterials, represents the most frequent causative agent involved in biofilm-associated infections of medical devices. Therefore, the research of new molecules able to interfere with S. epidermidis biofilm formation has a remarkable interest. In the present work, the attention was focused on Pseudomonas sp. TAE6080, an Antarctic marine bacterium able to produce and secrete an effective antibiofilm compound. The molecule responsible for this activity was purified by an activity-guided approach and identified by LC-MS/MS. Results indicated the active protein was a periplasmic protein similar to the Pseudomonas aeruginosa PAO1 azurin, named cold-azurin. The cold-azurin was recombinantly produced in E. coli and purified. The recombinant protein was able to impair S. epidermidis attachment to the polystyrene surface and effectively prevent biofilm formation.


Assuntos
Azurina , Pseudomonas , Azurina/metabolismo , Antibacterianos/metabolismo , Regiões Antárticas , Escherichia coli , Cromatografia Líquida , Espectrometria de Massas em Tandem , Biofilmes , Pseudomonas aeruginosa , Staphylococcus epidermidis
6.
Int J Biol Macromol ; 271(Pt 1): 132503, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38768913

RESUMO

The cold-adapted bacterium Variovorax sp. PAMC28711 possesses two distinct glycoside hydrolase (GH) families of trehalase, GH15 and GH37. While numerous studies have explored bacterial trehalase, the presence of two different trehalase genes within a single strain has not been reported until now. Interestingly, despite both GH37 and GH15 trehalases serving the same purpose of degrading trehalose, but do not share the sequence similarity. The substrate specificity assay confirmed that Vtre37 and Vtre15 displayed hydrolytic activity on α, α-trehalose. The key catalytic sites were identified as D280 and E469 in Vtre37 and E389 and E554 in Vtre15 through site-directed mutation and confirmed these two enzymes belong to trehalase. In addition, Vtre37 exhibited a relatively high level of enzyme activity of 1306.33 (±53.091) µmolmg-1, whereas Vtre15 showed enzyme activity of 408.39 (±12.503) µmolmg-1. Moreover, Vtre37 performed admirably showing resistance to ethanol (10 %), with high stable at acidic pH range. Furthermore, both prediction and experimental results indicate that validoxylamine A showed a potent inhibitory activity against Vtre37 trehalase with a Ki value of 16.85 nM. Therefore, we postulate that Vtre37 could be utilized as an ethanol enhancer and designed for screening inhibitors related to the trehalose degradation pathway. Additionally, we believe that characterizing these bacterial trehalase contributes to a better understanding of trehalose metabolism and its biological importance in bacteria.


Assuntos
Temperatura Baixa , Comamonadaceae , Trealase , Trealase/metabolismo , Trealase/genética , Trealase/química , Especificidade por Substrato , Comamonadaceae/enzimologia , Comamonadaceae/genética , Domínio Catalítico , Trealose/metabolismo , Trealose/farmacologia , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Sequência de Aminoácidos , Estabilidade Enzimática , Adaptação Fisiológica
7.
Data Brief ; 52: 109841, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38146304

RESUMO

Arthrobacter sp. EM1 is a cold-adapted bacterium isolated from the Antarctic region, which was known to exhibit mannan-degrading activity. Accordingly, this strain not only promises a cell factory for mannan-degrading enzymes, widely used in industry but also serves as a model organism to decipher its cold adaptation mechanism. Accordingly, whole genome sequencing of the EM1 strain was performed via Single Molecule Real Time sequencing under the PacBio platform, followed by genome HGAP de novo assembly and genome annotation through Rapid Annotation System Technology (RAST) server. The chromosome of this strain is 3,885,750 bp in size with a GC content of 65.8. The annotation predicted a total of 3607 protein-coding genes and 65 RNA genes, which were classified under 398 subsystems. The subsystem with the highest number of genes is carbohydrate metabolism (397 genes), which includes two genes encoding mannan-degrading enzymes (endoglucanase and α-mannosidase). This confirmed that the EM1 strain is able to produce cold-adapted mannan degrading enzymes. The complete genome sequence data have been submitted to the National Center for Biotechnology Information (NCBI) and have been deposited at GenBank (Bioproject ID Accession Number: PRJNA963062; Biosample ID Accession Number: SAMN34434776; GenBank: CP124836.1; https://www.ncbi.nlm.nih.gov/nuccore/CP124836).

8.
Plants (Basel) ; 13(3)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38337949

RESUMO

Rice (Oryza sativa) varieties are generated through breeding programs focused on local requirements. In Chile, the southernmost rice producer, rice productivity relies on the use and generation of temperate japonica germplasms, which need to be adapted to the intensifying effects of climate change. Advanced biotechnological tools can contribute to these breeding programs; new technologies associated with precision breeding, including gene editing, rely on procedures such as regeneration and gene transfer. In this study, the local rice varieties Platino, Cuarzo, Esmeralda, and Zafiro were evaluated for somatic embryogenesis potential using a process that involved the combined use of auxins and cytokinins. An auxin-based (2,4-D) general medium (2N6) allowed for the induction of embryogenic masses in all the genotypes. After induction, masses required culturing either in N6R (kinetin; Platino) or N6RN (BAP, kinetin, IBA, and 2,4-D; Cuarzo, Esmeralda, and Zafiro) to yield whole plants using regeneration medium (N6F, no hormone). The sprouting rates indicated Platino as the most responsive genotype; for this reason, this variety was evaluated for gene transfer. Fifteen-day-old embryo masses were assayed for Agrobacterium-mediated transformation using the bacterial strain EHA105 harboring pFLC-Myb/HPT/GFP, a modified T-DNA vector harboring a geminivirus-derived replicon. The vector included the green fluorescent protein reporter gene, allowing for continuous traceability. Reporter mRNA was produced as early as 3 d after agroinfiltration, and stable expression of the protein was observed along the complete process. These achievements enable further biotechnological steps in these and other genotypes from our breeding program.

9.
Microbiol Resour Announc ; 13(2): e0082023, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38179911

RESUMO

Mrakia hoshinonis JCM 32575 was isolated from glacial sediments on Ellesmere Island in the Canadian High Arctic and described as a new basidiomycetous yeast. This species does not require amino acids and vitamins for growth and can grow at sub-zero temperatures. Here, we report a draft genome sequence of this strain.

10.
Int J Biol Macromol ; 277(Pt 4): 134583, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39122074

RESUMO

Laccase (EC 1.10.3.2), as eco-friendly biocatalysts, holds immense potential for sustainable applications across various environmental and industrial sectors. Despite the growing interest, the exploration of cold-adapted laccases, especially their unique properties and applicability, remains limited. In this study, we have isolated, cloned, expressed, and purified a novel laccase from Peribacillus simplex (GenBank: PP430751), which was derived from permafrost layer. The recombinant laccase (PsLac) exhibited optimal activity at 30 °C and a pH optimum of 3.5. Remarkably, PsLac exhibited remarkable stability in the presence of organic solvents, with its enzyme activity increasing by 20 % after being incubated in a 30 % trichloromethane solution for 12 h, compared to its initial activity. Furthermore, the enzyme preserved 100 % of its activity after undergoing eight freeze-thaw cycles. Notably, the catalytic center of PsLac contains Zn2+ instead of the typically observed Cu2+ found in other laccases, and metal-ion substitution experiments raised the catalytic efficiency to 3-fold when Zn2+ was replaced with Fe2+. Additionally, PsLac has demonstrated a proficient ability to degrade phenolic pollutants, such as hydroquinone, even at a low temperature of 16 °C, positioning it as a promising candidate for environmental bioremediation and contributing to cleaner production processes.

11.
Bioresour Technol ; 399: 130539, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38458264

RESUMO

Carbonic anhydrase (CA) is currently under investigation because of its potential to capture CO2. A novel N-domain of ice nucleoproteins (INPN)-mediated surface display technique was developed to produce CA with low-temperature capture CO2 based on the mining and characterization of Colwellia sp. CA (CsCA) with cold-adapted enzyme structural features and catalytic properties. CsCA and INPN were effectively integrated into the outer membrane of the cell as fusion proteins. Throughout the display process, the integrity of the membrane of engineered bacteria BL21/INPN-CsCA was maintained. Notably, the study affirmed positive applicability, wherein 94 % activity persisted after 5 d at 15 °C, and 73 % of the activity was regained after 5 cycles of CO2 capture. BL21/INPN-CsCA displayed a high CO2 capture capacity of 52 mg of CaCO3/mg of whole-cell biocatalysts during CO2 mineralization at 25 °C. Therefore, the CsCA functional cell surface display technology could contribute significantly to environmentally friendly CO2 capture.


Assuntos
Dióxido de Carbono , Anidrases Carbônicas , Dióxido de Carbono/metabolismo , Anidrases Carbônicas/metabolismo , Técnicas de Visualização da Superfície Celular , Bactérias/metabolismo , Catálise
12.
J Agric Food Chem ; 72(17): 9955-9966, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38628059

RESUMO

Cold-adapted proteases are capable of efficient protein hydrolysis at reduced temperatures, which offer significant potential applications in the area of low temperature food processing. In this paper, we attempted to characterize cold-adapted proteases from Antarctic krill. Antarctic krill possesses an extremely active autolytic enzyme system in their bodies, and the production of peptides and free amino acids accompanies the rapid breakdown of muscle proteins following the death. The crucial role of trypsin in this process is recognized. A cold-adapted trypsin named OUC-Pp-20 from Antarctic krill genome was cloned and expressed in Pichia pastoris. Recombinant trypsin is a monomeric protein of 26.8 ± 1.0 kDa with optimum reaction temperature at 25 °C. In addition, the catalytic specificity of OUC-Pp-20 was assessed by identifying its hydrolysis sites through LC-MS/MS. OUC-Pp-20 appeared to prefer Gln and Asn at the P1 position, which is an amino acid with an amide group in its side chain. Hydrolysis reactions on milk and shrimp meat revealed that it can effectively degrade allergenic components in milk and arginine kinase in shrimp meat. These findings update the current knowledge of cold-adapted trypsin and demonstrate the potential application of OUC-Pp-20 in low temperature food processing.


Assuntos
Temperatura Baixa , Euphausiacea , Tripsina , Animais , Euphausiacea/química , Euphausiacea/enzimologia , Euphausiacea/genética , Euphausiacea/metabolismo , Hidrólise , Tripsina/metabolismo , Tripsina/química , Tripsina/genética , Especificidade por Substrato , Sequência de Aminoácidos , Espectrometria de Massas em Tandem , Estabilidade Enzimática , Regiões Antárticas
13.
Microorganisms ; 12(6)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38930441

RESUMO

The lack of efficient ways to dispose of lignocellulosic agricultural residues is a serious environmental issue. Low temperatures greatly impact the ability of organisms to degrade these wastes and convert them into nutrients. Here, we report the isolation and genomic characterization of a microbial consortium capable of degrading corn straw at low temperatures. The microorganisms isolated showed fast cellulose-degrading capabilities, as confirmed by scanning electron microscopy and the weight loss in corn straw. Bacteria in the consortium behaved as three diverse and functionally distinct populations, while fungi behaved as a single population in both diversity and functions overtime. The bacterial genus Pseudomonas and the fungal genus Thermoascus had prominent roles in the microbial consortium, showing significant lignocellulose waste-degrading functions. Bacteria and fungi present in the consortium contained high relative abundance of genes for membrane components, with amino acid breakdown and carbohydrate degradation being the most important metabolic pathways for bacteria, while fungi contained more genes involved in energy use, carbohydrate degradation, lipid and fatty acid decomposition, and biosynthesis.

14.
Microorganisms ; 12(5)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38792857

RESUMO

Our understanding of the antiphage defense system arsenal in bacteria is rapidly expanding, but little is known about its occurrence in cold-adapted bacteria. In this study, we aim to shed light on the prevalence and distribution of antiphage defense systems in cold-adapted bacteria, with a focus on CRISPR-Cas systems. Using bioinformatics tools, Prokaryotic Antiviral Defense LOCator (PADLOC) and CRISPRCasTyper, we mapped the presence and diversity of antiphage defense systems in 938 available genomes of cold-adapted bacteria from diverse habitats. We confirmed that CRISPR-Cas systems are less frequent in cold-adapted bacteria, compared to mesophilic and thermophilic species. In contrast, several antiphage defense systems, such as dXTPases and DRTs, appear to be more frequently compared to temperate bacteria. Additionally, our study provides Cas endonuclease candidates with a potential for further development into cold-active CRISPR-Cas genome editing tools. These candidates could have broad applications in research on cold-adapted organisms. Our study provides a first-time map of antiphage defense systems in cold-adapted bacteria and a detailed overview of CRISPR-Cas diversity.

15.
Biofilm ; 7: 100179, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38322580

RESUMO

Biofilms have great potential for producing valuable products, and recent research has been performed on biofilms for the production of compounds with biotechnological and industrial relevance. However, the production of recombinant proteins using this system is still limited. The recombinant protein production in microbial hosts is a well-established technology and a variety of expression systems are available. Nevertheless, the production of some recombinant proteins can result in proteolyzed, insoluble, and non-functional forms, therefore it is necessary to start the exploration of non-conventional production systems that, in the future, could be helpful to produce some "difficult" proteins. Non-conventional production systems can be based on the use of alternative hosts and/or on non-conventional ways to grow recombinant cells. In this paper, the use of the Antarctic marine bacterium Pseudoalteromonas haloplanktis TAC125 grown in biofilm conditions was explored to produce two fluorescent proteins, GFP and mScarlet. The best conditions for the production were identified by working on media composition, and induction conditions, and by building a new expression vector suitable for the biofilm conditions. Results reported demonstrated that the optimized system for the recombinant protein production in biofilm, although it takes longer than planktonic production, has the same potentiality as the classical planktonic approach with additional advantages since it needs a lower concentration of the carbon sources and doesn't require antibiotic addition. Moreover, in the case of mScarlet, the production in biofilm outperforms the planktonic system in terms of a better quality of the recombinant product.

16.
Ecol Evol ; 14(6): e11428, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38855316

RESUMO

Organisms inhabiting mountainous regions can experience large vertical environmental changes, and show different ecological characteristics between altitudes, thus facilitating allopatric fragmentation even in geographically close populations. This study compared the life-history patterns of a species of limnephilid caddisfly, Asynarchus sachalinensis, in several genetically differentiated populations between alpine and sub-alpine zones in a temperate mountainous region. We showed that in the sub-alpine populations, larval development started earlier with increasing water temperature in spring, and adult emergence was also earlier. The occurrence of adults was extremely low in mid-summer, probably due to summer diapause, followed by a larger number of ovary-developed females in autumn. On the other hand, in the alpine zone, increasing water temperature was delayed compared to the sub-alpine zone, and larval development occurred from early to mid-summer. Adult emergence and ovary-developed individuals were concentrated in mid-summer. Hence, summer diapause was not observed. These results indicated life-history differences between genetically differentiated populations at different altitudes. As the timing of adult occurrence and ovarian developmental patterns differ between populations at different altitudes, it is possible that reproductive isolation is facilitated or maintained between populations.

17.
Front Microbiol ; 14: 1280120, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38274748

RESUMO

Introduction: The research focuses on Rhododendron ferrugineum L., Nepal's national flower and Uttarakhand's state tree, thriving in high-altitude mountain ecosystems. Methodology and Result: A study conducted in Himachal Pradesh (Latitude: N 31° 6' 2.0088", Longitude: E 77° 10' 29.9136") identified leaf anomalies resembling rust-like manifestations in R. ferrugineum. These anomalies were traced back to the pathogenic fungus Curvularia tuberculata, marking the first documented case of its impact on R. ferrugineum in India. Discussion: This discovery emphasizes the need for vigilant monitoring, disease management research, and conservation efforts to protect the cultural and ecological significance of this iconic shrub. Beyond its immediate findings, the study introduces a novel dimension to Indian flora by associating C. tuberculata with R. ferrugineum, historically linked to monocotyledonous crops. The research methodology combines traditional microscopic examination with advanced genomic sequencing and phylogenetic analysis, enhancing pathogen identification accuracy. Future prospect: In a broader context, this research aligns with the United Nations Sustainable Development Goals (SDGs) by highlighting the importance of environmental preservation, conservation, and sustainable management. It underscores the intricate interplay between biodiversity, cultural heritage, and the need for holistic solutions. Overall, this study calls for proactive measures to protect R. ferrugineum's cultural and ecological heritage and emphasizes the significance of interdisciplinary approaches in addressing emerging ecological threats.

18.
Vopr Virusol ; 68(6): 526-535, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38156568

RESUMO

INTRODUCTION: Polymerase proteins PB1 and PB2 determine the cold-adapted phenotype of the influenza virus A/Krasnodar/101/35/59 (H2N2), as was shown earlier. OBJECTIVE: The development of the reporter construct to determine the activity of viral polymerase at 33 and 37 °C using the minigenome method. MATERIALS AND METHODS: Co-transfection of Cos-1 cells with pHW2000 plasmids expressing viral polymerase proteins PB1, PB2, PA, NP (minigenome) and reporter construct. RESULTS: Based on segment 8, two reporter constructs were created that contain a direct or inverted NS1-GFP-NS2 sequence for the expression of NS2 and NS1 proteins translationally fused with green fluorescent protein (GFP), which allowed the evaluation the transcriptional and/or replicative activity of viral polymerase. CONCLUSION: Polymerase of virus A/Krasnodar/101/35/59 (H2N2) has higher replicative and transcriptional activity at 33 °C than at 37 °C. Its transcriptional activity is more temperature-dependent than its replicative activity. The replicative and transcriptional activity of polymerase A/Puerto Rico/8/34 virus (H1N1, Mount Sinai variant) have no significant differences and do not depend on temperature.


Assuntos
Alphainfluenzavirus , Vírus da Influenza A Subtipo H1N1 , Orthomyxoviridae , Vírus da Influenza A Subtipo H1N1/genética , Orthomyxoviridae/genética , Orthomyxoviridae/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo , Temperatura , RNA Polimerase Dependente de RNA/genética , RNA Polimerase Dependente de RNA/metabolismo
19.
Bioresour Bioprocess ; 9(1): 18, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38647816

RESUMO

We investigated the dye-removal potential of a collection of 61 cold-adapted yeasts from the King George Island, Antarctica, on agar plates supplemented with 100 mg L-1 of several textile dyes; among which isolates 81% decolorized Reactive Black 5 (RB-5), with 56% decolorizing Reactive Orange 16, but only 26% doing so with Reactive Blue 19 and Acid Blue 74. Furthermore, we evaluated the ligninolytic potential using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic-acid) diammonium salt-, 3,5-dimethoxy-4-hydroxybenzaldehydazine-, or manganese-supplemented plates but detected no activity, possibly due to a dye-removal mechanism involving reductases. The removal kinetics were studied in liquid medium supplemented with 100 mg L-1 of RB-5 in a selection of 9 yeasts. The highest volumetric-removal rates (η) were found for Candida sake 41E (4.14 mg L-1 h-1), Leucosporidium muscorum F20A (3.90 mg L-1 h-1), and Cystofilobasidium infirmominiatum F13E (3.90 mg L-1 h-1). Different UV-Vis spectra were obtained if the dye removal occurred by biodegradation or biosorption/bioaccumulation. L. muscorum F20A was selected to study the dye-removal mechanism of RB-5 and the effect of different chemical and environmental parameters on the process. Optimum dye-removal conditions were obtained with 10 g L-1 of glucose within an initial medium pH range of 5.0 to 6.0. Up to 700 mg L-1 of dye could be removed in 45 h. High-performance liquid chromatography profiles obtained were consistent with a biodegradation of the dye. Phytotoxicity was estimated by calculating the 50%-inhibition concentration (IC50) with Lactuca sativa L. seeds. These findings propose psychrophilic yeasts as a novel environmentally suitable alternative for the treatment of dye-industry wastewaters.

20.
Bioresour Bioprocess ; 8(1): 121, 2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38650291

RESUMO

The cold-active pectate lyases have drawn increasing attention in food and biotechnological applications due to their ability to retain high catalytic efficiency under lower temperatures, which could be helpful for energy saving, cost reduction and flavor preservation. Herein, a new cold-tolerant pectate lyase (ErPelPL1) gene from Echinicola rosea was cloned and heterologously expressed in Escherichia coli. Interestingly, ErPelPL1 retained high catalytic activity even at a low temperature (4 °C). ErPelPL1 exhibited optimal activity at 35 â„ƒ, pH 8.0 with 1 mM of Ca2+. It showed high specific activity towards polygalacturonic acid (34.7 U/mg) and sodium polygalacturonate (59.3 U/mg). The combined thin-layer chromatography (TLC), fast protein liquid chromatography (FPLC) and electrospray ionization mass spectrometry (ESI-MS) results indicated that ErPelPL1 endolytically degraded pectic substances into the oligosaccharides with degrees of depolymerization (Dps) of 1-6. In conclusion, this study mainly conducted biochemical characterization and product analysis of a cold-tolerant pectate lyase. Therefore, it provides a promising enzyme candidate for food and biotechnological applications.

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