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1.
J Agric Food Chem ; 72(29): 16378-16389, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38980661

RESUMO

Rice (Oryza sativaL.) is a crucial staple food crop globally, facing significant challenges from various pests that affect crop productivity and quality. Conventional pesticide usage has limitations, necessitating the development of sustainable pest management strategies. This study focuses on the expression, purification, and functional characterization of Oryzacystatin II (OC-II), a protein derived from O. sativaL. Indica rice, with the intent to evaluate its potential as a bioinsecticide against rice pests. The OC-II gene was expressed and purified, and purification confirmed its molecular weight (∼12 kDa) and protein sequence through LC-MS/MS analysis and Western blotting. The IC50 value of OC-II was calculated as 0.06 µM, and the inhibition was identified as a competitive inhibition. The protein exhibited efficient control of both pests at the nymph and adult stages, with lower probing marks observed on treated plants. The inhibition of cathepsin B enzyme activity in insects further confirmed the bioactivity of the OC-II protein. Molecular docking and molecular dynamics simulations provided insights into the interaction between the OC-II protein and cathepsin enzymes reported in BPH and WBPH. Further investigations can focus on optimizing production methods and exploring the specificity and efficacy of the OC-II protein against other crop pests to enhance its practical applications.


Assuntos
Inseticidas , Simulação de Acoplamento Molecular , Oryza , Proteínas de Plantas , Oryza/genética , Oryza/química , Oryza/metabolismo , Animais , Inseticidas/química , Inseticidas/farmacologia , Proteínas de Plantas/genética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Controle Biológico de Vetores
2.
Infect Drug Resist ; 17: 2389-2399, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903152

RESUMO

Objective: The most common extraintestinal pathogen and infection site is uropathogenic Escherichia coli (UPEC), which causes urinary tract infections (UTIs). UPEC is also a common pathogen in bloodstream infections; in severe cases, it can lead to death. Although host and bacterial virulence factors have been demonstrated to be associated with UTI pathogenesis, the role of the related contributing factors in UTI and urinary source bacteremia is not yet fully understood. This study aimed to compare and analyze the factors contributing to urinary bacteremia in patients with UTI. Methods: A total of 171 E. coli strains collected from patients with UTI and urinary source bacteremia at Chiayi Christian Hospital were used. Phylogenetic groups and virulence factors were determined using PCR. Drug resistance patterns were determined using the disk diffusion assay. Results: Previous studies have demonstrated that fimbriae and papGII may be associated with first-step infections and severe UTIs, respectively. As expected, highly virulent E. coli strains (belonging to the phylogenetic B2 and D groups) were dominant in the bacteremic UTI (90%) and UTI (86.27%) groups. However, our results showed that the UTI group had a significantly higher prevalence of sfa/focDE (belonging to the S and FIC fimbriae) than the bacteremic UTI group (29.4% vs 12.5%; p=0.008). In the bacteremic group, we found that sfa/focDE was only detected in highly virulent strains. The bacteremic UTI group had a significantly higher prevalence of papGII (belonging to P fimbriae) than the UTI group (55.8% vs 37.3%; p=0.026). In addition, the P fimbriae gene cluster, including papC, papEF, and papGII, was predominant in highly virulent strains. Notably, our results show that multidrug-resistant (MDR) strains were significantly less virulent than non MDR strains. Conclusion: Taken together, our results provide insights into the contributing factors in patients with UTI and urinary bacteremia.

3.
AIMS Microbiol ; 10(1): 220-238, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525044

RESUMO

Plant probiotic bacteria are a versatile group of bacteria isolated from different environmental sources to improve plant productivity and immunity. The potential of plant probiotic-based formulations is successfully seen as growth enhancement in economically important plants. For instance, endophytic Bacillus species acted as plant growth-promoting bacteria, influenced crops such as cowpea and lady's finger, and increased phytochemicals in crops such as high antioxidant content in tomato fruits. The present review aims to summarize the studies of Bacillus species retaining probiotic properties and compare them with the conventional fertilizers on the market. Plant probiotics aim to take over the world since it is the time to rejuvenate and restore the soil and achieve sustainable development goals for the future. Comprehensive coverage of all the Bacillus species used to maintain plant health, promote plant growth, and fight against pathogens is crucial for establishing sustainable agriculture to face global change. Additionally, it will give the latest insight into this multifunctional agent with a detailed biocontrol mechanism and explore the antagonistic effects of Bacillus species in different crops.

4.
Sci Total Environ ; 892: 164531, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37268142

RESUMO

Polystyrene (PS) is a crucial material for modern plastic manufacturers, but its widespread use and direct discard in the environment severely affect the food chain. This review provides a detailed study on the impact of PS microplastics (PS-MPs) on the food chain and the environment, including information on their mechanism, degradation process, and toxicity. The accumulation of PS-MPs in organisms' different organs leads to various adverse reactions, such as reduced body weight, premature deaths, pulmonary diseases, neurotoxicity, transgenerational issues, oxidative stress, metabolic alterations, ecotoxicity, immunotoxicity, and other dysfunctions. These consequences affect diverse elements in the food chain, spanning from aquatic species to mammals and humans. The review also addresses the need for sustainable plastic waste management policies and technological developments to prevent the adverse impacts of PS-MPs on the food chain. Additionally, it emphasizes the importance of developing a precise, flexible, and effective methodology for extracting and quantifying PS-MPs in food, considering their characteristics like particle size, polymer types, and forms. While several studies have focused on the toxicity of polystyrene microplastics (PS-MPs) in aquatic species, further investigation is required to understand the mechanisms by which they are transferred across multiple trophic levels. Therefore, this article serves as the first comprehensive review, examining the mechanism, degradation process, and toxicity of PS-MPs. It presents an analysis of the current research landscape of PS-MPs in the global food chain, providing insights for future researchers and governing organizations to adopt better approaches to managing PS-MPs and preventing their adverse impacts on the food chain. As far as we know this is the first article on this specific and impactant topic.


Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Animais , Microplásticos/toxicidade , Poliestirenos/toxicidade , Plásticos/toxicidade , Cadeia Alimentar , Peso Corporal , Poluentes Químicos da Água/toxicidade , Mamíferos
5.
Nanomaterials (Basel) ; 12(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36144915

RESUMO

Nanotechnology has become the most effective and rapidly developing field in the area of material science, and silver nanoparticles (AgNPs) are of leading interest because of their smaller size, larger surface area, and multiple applications. The use of plant sources as reducing agents in the fabrication of silver nanoparticles is most attractive due to the cheaper and less time-consuming process for synthesis. Furthermore, the tremendous attention of AgNPs in scientific fields is due to their multiple biomedical applications such as antibacterial, anticancer, and anti-inflammatory activities, and they could be used for clean environment applications. In this review, we briefly describe the types of nanoparticle syntheses and various applications of AgNPs, including antibacterial, anticancer, and larvicidal applications and photocatalytic dye degradation. It will be helpful to the extent of a better understanding of the studies of biological synthesis of AgNPs and their multiple uses.

6.
Front Neurosci ; 15: 719933, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34531716

RESUMO

This study was designed to investigate stressful social experience (SSE) in early life by examining how it can induce alterations in the microbiota-gut-brain axis. To test this, different experimental groups of pups experienced the presence of either a stranger (S) with mother (M+P+S) or without their mother (MS+S-M). Animals were assessed for anxiety-like behavior and high-throughput bacterial 16s rRNA sequencing was performed to analyze the structure of the gut microbiota. Our analysis revealed that early life SSE induced anxiety-like behavior and reduced the diversity and richness of gut microbiota. In the second experiment, all groups were supplemented with Lactobacillus paracasei HT6. The findings indicated that Lactobacillus supplementation had a significant beneficial effect on anxiety-like behavior in stressed rats (MS, M+P+S, and MS + S-M) accompanied by normalized levels of adrenocorticotropic hormone (ACTH), corticosterone (CORT), glucocorticoid receptor (GR), serotonin (5-HT), dopamine (DA), and noradrenaline (NA). Concomitantly, the expression of microRNA (miR)-124a was down-regulated and miR-132, caspase-3, glutamate receptors (GluR1, GluR 2; NR2A, and NR2B) were up-regulated in stressed groups but remained unchanged by Lactobacillus supplementation in stressed individuals. This indicates that stress-associated GluR1-GR altered interactions can be significantly prevented by Lactobacillus supplementation. Analysis of the fecal metabolite profile was undertaken to analyze the effect of Lactobacillus, revealing that five predicted neuroactive microbial metabolites were reduced by early life SSE. Our results showed a potential link between Lactobacillus supplementation and beneficial effects on anxiety-like behavior, the mechanism of which could be potentially mediated through stress hormones, neurotransmitters, and expression of miRNAs, glutamate receptors, and the microbiota-gut-brain axis.

7.
J Food Sci Technol ; 58(8): 3235-3242, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34294986

RESUMO

Tannase is a widely used enzyme that improves the quality of tea by facilitating the release of water-soluble polyphenolic compounds, as well as reduces the formation of tea creams. The microbial tannase enzymes are often employed for tea biotransformation by hydrolyses esters of phenolic acids, including the gallated polyphenols found in blacks teas. The study was focused to investigate the tannase enzyme mediated biotransformation of black tea such as CTC-(Crush, tear, curl) & Kangra orthodox which are commonly used by the south Indian peoples. HPLC spectral analysis revealed that tannase treatment on tea cream formation (CTC & Kangra orthodox tea) allows the hydrolysis of the EGC, GA, ECG, and EGCG. A significant reduction in the formation of tea cream and increased antioxidant activity has been observed in the CTC (1.62 fold) and Kangra orthodox (1.55 fold). The results revealed that tannase treatment helps to improve the quality of black tea infusions with respect to cream formation, the intensity of colour, and sensory characteristics of tea. The result of this study indicates that E. cloacae 41 produced tannase can be used to improve the quality of both tea samples.

8.
Braz J Microbiol ; 52(3): 1385-1395, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33856662

RESUMO

Although Phu Quoc island, Gulf of Thailand possesses diverse marine and coastal ecosystems, biodiversity and metabolic capability of microbial communities remain poorly investigated. The aim of our study was to evaluate the biodiversity and metabolic potential of sediment microbial communities in Phu Quoc island. The marine sediments were collected from three different areas and analyzed by using 16S rRNA gene-based amplicon approach. A total of 1,143,939 reads were clustered at a 97% sequence similarity into 8,331 unique operational taxonomic units, representing 52 phyla. Bacteria and archaea occupied averagely around 86% and 14%, respectively, of the total prokaryotic community. Proteobacteria, Planctomycetes, Chloroflexi, and Thaumarchaeota were the dominant phyla in all sediments, which were involved in nitrogen and sulfur metabolism. Sediments harboring of higher nitrogen sources were found to coincide with increased abundance of archaeal phylum Thaumarchaeota. Predictive functional analysis showed high abundance prokaryotic genes associated with nitrogen cycling including nifA-Z, amoABC, nirA, narBIJ, napA, nxrAB, nrfA-K, nirBD, nirS, nirK, norB-Z, nlnA, ald, and ureA-J, based on taxonomic groups detected by 16S rRNA sequencing. Although the key genes involved in sulfur cycling were found to be at low to undetectable levels, the other genes encoding for sulfur-related biological processes were present, suggesting that alternative pathways may be involved in sulfur cycling at our study site. In conclusion, our study for the first time shed light on diversity of microbial communities in Phu Quoc island.


Assuntos
Sedimentos Geológicos/microbiologia , Microbiota , Nitrogênio , Enxofre/química , Archaea/classificação , Bactérias/classificação , Biodiversidade , Nitrogênio/química , RNA Ribossômico 16S/genética , Tailândia
9.
Bot Stud ; 55(1): 18, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28510930

RESUMO

BACKGROUND: Phytocystatins are natural inhibitors of cysteine protease, and may regulate endo- or exo-genous proteolytic activities in plants. They are classified into Group I and II differing by the presence of C-terminal extension of Group II. A cDNA fragment encoding a Group II phytosystatin, SiCYS was previously obtained from sesame seeds. RESULTS: SiCYS as well as its two structural domains, N-terminal and C-terminal domains (SiCYS-N and SiCYS-C), was expressed in Escherichia coli. The recombinant SiCYS and SiCYS-N showed inhibitory activity against papain. The K i values of SiCYS and SiCYS-N were ~1.9 ×10-8 M and ~7.9 ×10-8 M, respectively. All the three recombinants possessed comparable ability to inhibit spore germination of Trichoderma reesei, Aspergillus sydowii, and Helminthosporium sesamum. Similar protein profile including proteases in germinating seeds was found in proteins purified by the SiCYS, SiCYS-N or SiCYS-C coupling affinity column. CONCLUSION: SiCYS exhibited more effective papain-inhibitory activity than SiCYS-N; while SiCYS-C had almost no inhibitory activity. All displayed similar antifungal activities indicating that there is no correlation between antifungal and papain-inhibitory activities. Structural and sequence analyses suggest that the C-terminal domain of SiCYS may be originated from gene duplication to enhance its inhibitory activity.

10.
Biosci Biotechnol Biochem ; 68(8): 1681-9, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15322351

RESUMO

A cDNA fragment encoding the cysteine protease inhibitor, cystatin, was cloned from pineapple (Ananas comosus) stem. This clone was constructed in a fusion vector and was easily over-expressed in Escherichia coli; satisfactory over-expression of non-fusion cystatin was achieved after an additional start codon was inserted prior to its coding sequence. Both recombinant cystatins were predominately found in the soluble fraction of the cell extract, and were demonstrated to be functionally active in a reverse zymographic assay. The fusion and non-fusion cystatins were separately purified to homogeneity via a His-tag or papain-coupling affinity column. Effective inhibitory activity against papain was detected with both the fusion and non-fusion cystatins with comparable K(i) values of 1.18 x 10(-10) M and 9.53 x 10(-11) M, respectively. The recombinant cystatins were found to be thermally stable up to 60 degrees C. Inhibition of the endogenous protease activity in minced fish muscle revealed that the recombinant pineapple cystatins might be an adequate stabilizer to prevent protein degradation during industrial food processing.


Assuntos
Ananas/metabolismo , Códon de Iniciação/genética , Cistatinas/genética , Papaína/metabolismo , Proteínas Recombinantes/genética , Sequência de Aminoácidos , Cromatografia de Afinidade , Clonagem Molecular , Cistatinas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Dados de Sequência Molecular , Proteínas Recombinantes/metabolismo
11.
J Biotechnol ; 111(1): 51-7, 2004 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15196769

RESUMO

An expression/purification system was developed using artificial oil bodies (AOB) as carriers for producing recombinant proteins. A target protein, green fluorescent protein (GFP), was firstly expressed in Escherichia coli as an insoluble recombinant protein fused to oleosin, a unique structural protein of seed oil bodies, by a linker sequence susceptible to factor Xa cleavage. Artificial oil bodies were constituted with triacylglycerol, phospholipid, and the insoluble recombinant protein, oleosin-Xa-GFP. After centrifugation, the oleosin-fused GFP was exclusively found on the surface of artificial oil bodies presumably with correct folding to emit fluorescence under excitation. Proteolytic cleavage with factor Xa separated soluble GFP from oleosin embedded in the artificial oil bodies; thus after re-centrifugation, GFP of high yield and purity was harvested simply by concentrating the ultimate supernatant.


Assuntos
Proteínas de Escherichia coli/biossíntese , Proteínas de Escherichia coli/isolamento & purificação , Fator Xa/metabolismo , Proteínas de Plantas/metabolismo , Engenharia de Proteínas/métodos , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/isolamento & purificação , Centrifugação/métodos , Proteínas de Escherichia coli/genética , Fator Xa/genética , Corpos de Inclusão/metabolismo , Peptídeos/genética , Peptídeos/isolamento & purificação , Peptídeos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação
12.
J Agric Food Chem ; 52(10): 3115-9, 2004 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-15137862

RESUMO

A method was developed for production of sesame cystatin, a thermostable cysteine protease inhibitor. Sesame cystatin was first expressed in Escherichia coli as an insoluble recombinant protein fused to oleosin, a unique structural protein of seed oil bodies, by a short hydrophilic linker peptide. Stable artificial oil bodies were constituted with triacylglycerol, phospholipid, and the insoluble oleosin-cystatin fusion protein. After centrifugation, the oleosin-cystatin fusion protein was exclusively found in the artificial oil bodies. Proteolytic cleavage with papain, a cysteine protease effectively inhibited by cystatin, separated soluble cystatin from oleosin that was firmly embedded in the artificial oil bodies. After recentrifugation, papain that coexisted with cystatin in the collected supernatant was denatured by incubating at 55 degrees C for 30 min. The insoluble denatured papain was removed by one more centrifugation, and the expressed cystatin of high yield and purity was harvested simply by concentrating the ultimate supernatant. Comparable inhibitory activity toward papain was observed between the expressed cystatin and the native one purified from sesame seeds. This method is presumably applicable to production of other protease inhibitors whose target proteases are economically available.


Assuntos
Cistatinas/genética , Escherichia coli/genética , Expressão Gênica , Sementes/ultraestrutura , Sesamum/química , Cistatinas/farmacologia , Inibidores de Cisteína Proteinase , Organelas , Papaína/antagonistas & inibidores , Proteínas de Plantas/genética , Proteínas Recombinantes de Fusão/farmacologia , Sementes/química
13.
J Agric Food Chem ; 52(5): 1350-6, 2004 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-14995145

RESUMO

A cDNA fragment encoding cystatin, a cysteine protease inhibitor, was obtained from maturing sesame seeds. The clone was constructed in a nonfusion or fusion vector and then overexpressed in Escherichia coli. The recombinant cystatins were found in the soluble fraction of cell extract and were demonstrated to be functionally active in a reverse zymographic assay. The corresponding endogenous 22 kDa cystatin of low abundance in mature seeds was purified to homogeneity via a papain-coupling affinity column and confirmed by western blotting with antibodies against the recombinant cystatin. Both endogenous and recombinant cystatin proteins showed effective inhibitory activities against papain with K(i) values of 7.89 x 10(-8) M and 2.77 x 10(-8) M, respectively. Immunodetection indicated that cystatin was specifically expressed in maturing seeds and rapidly degraded in germination. Accordingly, zymographic and inhibition analyses showed that sesame cystatin could not inhibit the de novo synthesized proteases in germinating seeds. It is suggested that sesame cystatin may play a role in the regulation of endogenous cysteine proteases during seed maturation and germination.


Assuntos
Clonagem Molecular , Cistatinas/genética , Expressão Gênica , Sementes/química , Sesamum/química , Sequência de Aminoácidos , Proteínas de Transporte/antagonistas & inibidores , Cistatinas/química , Cistatinas/farmacologia , DNA Complementar/isolamento & purificação , DNA de Plantas/química , DNA de Plantas/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Dados de Sequência Molecular , Alinhamento de Sequência
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