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1.
Fish Shellfish Immunol ; 117: 320-327, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34246784

RESUMO

The polymeric immunoglobulin receptor (pIgR) plays an important role in mediating the transcytosis of polymeric immunoglobulins (pIgs) to protect organisms against pathogen invasion. Here, a polyclonal antibody against grass carp (Ctenopharyngodon idellus) recombinant pIgR was developed by immunizing New Zealand white rabbit, and the responses of pIgR, IgM and IgZ were analyzed after bath immunization and intraperitoneal administration with Flavobacterium columnare. The results showed that pIgR transcription level was similar to IgM and IgZ, but pIgR rose much faster and peaked earlier than IgM and IgZ; the pIgR mRNA levels were higher in the skin and spleen for both immunized groups, while IgM and IgZ mRNA expression were higher in skin, gills, and intestines in bath immersion group, or spleen and head kidney in intraperitoneal immunization group. ELISA revealed that the IgM, IgZ and pIgR protein levels were up-regulated in skin mucus, gill mucus, gut mucus and bile, reaching a higher peak level earlier in skin mucus and gill mucus in bath immersion group, but a higher peak level in bile in injection group. Moreover, secretory component molecules were detected in grass carp's skin, gill and intestine mucus and bile, but not in serum, which molecular mass was near the theoretical mass obtained from the sequence of grass carp pIgR. These results demonstrated that bath and intraperitoneal immunization up-regulated pIgR and secretory Ig expression in secretions, which provided more insights into the role of pIgR in immunity and offer insight into ways of protecting teleost against pathogen invasion.


Assuntos
Carpas/imunologia , Doenças dos Peixes/imunologia , Proteínas de Peixes/imunologia , Infecções por Flavobacteriaceae/imunologia , Flavobacterium , Imunoglobulinas/imunologia , Animais , Bile/imunologia , Carpas/microbiologia , Infecções por Flavobacteriaceae/veterinária , Brânquias/imunologia , Muco/imunologia , Coelhos , Proteínas Recombinantes/imunologia , Pele/imunologia
2.
Front Immunol ; 12: 633324, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34262558

RESUMO

In the process of microbial invasion, the inflammation reaction is induced to eliminate the pathogen. However, un-controlled or un-resolved inflammation can lead to tissue damage and death of the host. MicroRNAs (miRNAs) are the signaling regulators that prevent the uncontrolled progress of an inflammatory response. Our previous work strongly indicated that miR-142a-3p is related to the immune regulation in grass carp. In the present study, we found that the expression of miR-142a-3p was down-regulated after infection by Aeromonas hydrophila. tnfaip2 and glut3 were confirmed as be the target genes of miR-142a-3p, which were confirmed by expression correlation analysis, gene overexpression, and dual luciferase reporter assay. The miR-142a-3p can reduce cell viability and stimulate cell apoptosis by targeting tnfaip2 and glut3. In addition, miR-142a-3p also regulates macrophage polarization induced by A. hydrophila. Our results suggest that miR-142a-3p has multiple functions in host antibacterial immune response. Our research provides further understanding of the molecular mechanisms between miRNAs and their target genes, and provides a new insights for the development of pro-resolution strategies for the treatment of complex inflammatory diseases in fish.


Assuntos
Apoptose/genética , Carpas/genética , Citocinas/genética , Transportador de Glucose Tipo 3/genética , Infecções por Bactérias Gram-Negativas/veterinária , Macrófagos/fisiologia , MicroRNAs/genética , Aeromonas hydrophila/imunologia , Aeromonas hydrophila/patogenicidade , Animais , Carpas/imunologia , Carpas/microbiologia , Células Cultivadas , Citocinas/classificação , Infecções por Bactérias Gram-Negativas/imunologia , Inflamação/imunologia , Rim/citologia , Rim/microbiologia , Macrófagos do Fígado/microbiologia , Ativação de Macrófagos , MicroRNAs/classificação , Transdução de Sinais
3.
Ultrason Sonochem ; 76: 105660, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34271395

RESUMO

A novel technique for treating grass carp by combining plasma functionalized liquids and ultrasound to inactivate bacteria was developed. The effects of the plasma functionalized liquids (PFL) including plasma functionalized water (PFW) and buffer (PFB) and their respective combination with ultrasound treatment (USPFW and USPFB) on the oxidative and physical qualities of grass carp were also investigated. Individual applications of PFW and PFB significantly reduced the populations of Escherichia coli and Shewanella putrefaciens in the range of 0.31-1.18 log CFU/g, compared with the control with a reduction of 0.18 log CFU/g, while combined treatments of USPFW and USPFB presented additional reductions of 0.05-0.65 log CFU/g, with potential synergy demonstrated for PFW and ultrasound. The treatment resulted in improved biomedical index and nutritional value of fatty acids and lipids, protein structural unfolding, increased lipid oxidation and protein degradation with values within the acceptable limits, and the combined treatment was more effective for retarding the hardness reduction in grass carp, while the colour change was also significantly affected, resulting in increased whiteness. The results indicated that the combined treatments may be a promising approach to improving the quality of seafood products.


Assuntos
Carpas/microbiologia , Qualidade dos Alimentos , Viabilidade Microbiana/efeitos dos fármacos , Gases em Plasma/farmacologia , Ondas Ultrassônicas , Animais
4.
Front Immunol ; 12: 690234, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34220849

RESUMO

As an intermediate substance of the tricarboxylic acid cycle and a precursor substance of glutamic acid synthesis, the effect of alpha-ketoglutarate on growth and protein synthesis has been extensively studied. However, its prevention and treatment of pathogenic bacteria and its mechanism have not yet been noticed. To evaluate the effects of alpha-ketoglutarate on intestinal antioxidant capacity and immune response of Songpu mirror carp, a total of 360 fish with an average initial weight of 6.54 ± 0.08 g were fed diets containing alpha-ketoglutarate with 1% for 8 weeks. At the end of the feeding trial, the fish were challenged with Aeromonas hydrophila for 2 weeks. The results indicated that alpha-ketoglutarate supplementation significantly increased the survival rate of carp after infection with Aeromonas hydrophila (P < 0.05), and the contents of immune digestion enzymes including lysozyme, alkaline phosphatase and the concentration of complement C4 were markedly enhanced after alpha-ketoglutarate supplementation (P < 0.05). Also, appropriate alpha-ketoglutarate increased the activities of total antioxidant capacity and catalase and prevented the up-regulation in the mRNA expression levels of pro-inflammatory cytokines including tumor necrosis factor-α, interleukin-1ß, interleukin-6, and interleukin-8 (P < 0.05). Furthermore, the mRNA expression levels of toll-like receptor 4 (TLR4), and nuclear factor kappa-B (NF-κB) were strikingly increased after infection with Aeromonas hydrophila (P < 0.05), while the TLR4 was strikingly decreased with alpha-ketoglutarate supplementation (P < 0.05). Moreover, the mRNA expression levels of tight junctions including claudin-1, claudin-3, claudin-7, claudin-11 and myosin light chain kinases (MLCK) were upregulated after alpha-ketoglutarate supplementation (P < 0.05). In summary, the appropriate alpha-ketoglutarate supplementation could increase survival rate, strengthen the intestinal enzyme immunosuppressive activities, antioxidant capacities and alleviate the intestinal inflammation, thereby promoting the intestinal immune responses and barrier functions of Songpu mirror carp via activating TLR4/MyD88/NF-κB and MLCK signaling pathways after infection with Aeromonas hydrophila.


Assuntos
Aeromonas hydrophila/patogenicidade , Antioxidantes/metabolismo , Carpas/microbiologia , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Imunidade Inata/efeitos dos fármacos , Mucosa Intestinal/microbiologia , Ácidos Cetoglutáricos/farmacologia , Aeromonas hydrophila/imunologia , Ração Animal , Animais , Carpas/crescimento & desenvolvimento , Carpas/imunologia , Carpas/metabolismo , Suplementos Nutricionais , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/metabolismo , Infecções por Bactérias Gram-Negativas/microbiologia , Interações Hospedeiro-Patógeno , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Quinase de Cadeia Leve de Miosina/genética , Quinase de Cadeia Leve de Miosina/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Transdução de Sinais , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-34170217

RESUMO

A novel actinobacterium, designated CFH 10395T, was isolated from the foregut of grass carp (Ctenopharyngodon idella), which had been fed with ginseng extract supplement. The taxonomic position was investigated by a polyphasic approach. Cells of CFH 10395T were Gram-staining-positive, aerobic, ovoid-shaped, non-spore-forming and non-motile. On the basis of the results of 16S rRNA gene sequence analysis, CFH 10395T was most closely related to Brachybacterium endophyticum KCTC 49087T, Brachybacterium squillarum JCM 16464T and Brachybacterium paraconglomeratum JCM 17781T (97.85%, 97.51 and 97.29% similarity, respectively). CFH 10395T grew at 4-37 °C, pH 5.0-9.0 and in the presence of up to 10.0 % NaCl (w/v). The dominant menaquinone was MK-7. The whole-cell sugars were rhamnose, glucose, mannose and galactose. meso-diaminopimelic acid was the diagnostic diamino acid in the cell-wall peptidoglycan. The major fatty acids were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0. The genome size was 3.99 Mbp with a DNA G+C content of 71.9 mol%. On the basis of the results of phylogenetic analysis, physiological properties, chemotaxonomic characteristics, low average nucleotide identity (ANI) and digital DDH (dDDH) results [ANI calculated using MUMmer (ANIm) <87 %, ANI calculated using blast (ANIb) <83 % and dDDH <23 %], it is concluded that CFH 10395T represents a novel species of the genus Brachybacterium, for which the name Brachybacterium subflavum sp. nov., is proposed. The type strain is CFH 10395T (=CGMCC 1.13804T=KCTC 49235T).


Assuntos
Actinobacteria/classificação , Actinobacteria/isolamento & purificação , Carpas/microbiologia , Filogenia , Actinobacteria/genética , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/análise , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
Arch Microbiol ; 203(7): 4705-4714, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34185117

RESUMO

Cyprinus carpio is an important freshwater fish in aquaculture. It was used for the isolation of potential probiotic strain for aquaculture applications. The most dominant strain was isolated on MRS agar from the gastrointestinal (GI) of C. carpio and identified as Lysinibacillus macroides using molecular marker 16S rRNA gene. Various probiotic properties such as acid and bile tolerance and antibiotic susceptibility were analysed under in vitro conditions. Further, formulate pelletized feed using probiotic (L. macroides) in different concentrations (2, 4, 6 and 8%). Rearing of C. carpio was carried out 45 days and fed with formulated feed. The highest length (5.14 ± 0.07 cm) and weight (3.56 ± 0.07 g) of C. carpio fingerlings was recorded in the 8% LM probiotic pelletized feed, while in fingerlings fed with control showed lower in the length (3.02 ± 0.13 cm) and the weight (0.92 ± 0.04 g) on the 45th day of the experiment. Both percentage of weight gain (PWG) and specific growth rate (SGR) were significantly increased (P < 0.05) of C. carpio fingerlings fed with probiotic feed compared to control feed. Hence, the use of probiotic bacteria could be an encouraging alternative feed for future endeavours in the field of aquaculture. In conclusion, L. macroides can serve as probiotic for sustainable, competitive and promising beneficial bacteria to aquaculture industry.


Assuntos
Bacillaceae , Carpas , Probióticos , Animais , Aquicultura , Bacillaceae/fisiologia , Carpas/crescimento & desenvolvimento , Carpas/microbiologia , RNA Ribossômico 16S/genética
7.
Ultrason Sonochem ; 76: 105609, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34157567

RESUMO

A novel method of thermoultrasound-assisted plasma functionalized buffer (PFB) for decontaminating grass carp was evaluated using the Box-Behnken design (BBD) with processing variables including PFB generating voltage (PV), ultrasound treatment time (UT) and temperature (TP). The predicted models were found to be significant (p < 0.05) and displayed sufficient fitness with experimental data as indicated by non-significant (p > 0.05) lack of fit and high coefficient of determination (R2≥0.97) values. The optimum decontamination conditions for the responses of S. putrefaciens and S. Typhimurium were PV of 66 V, UT of 14.90 min and TP of 60 ℃, achieving reductions of 4.40 and 3.97 log CFU/g, respectively, with a desirability of 0.998. Among the variables, temperature presented higher significance for inactivating bacteria and the production of volatile basic nitrogen and lipid peroxidation under the optimized conditions were within the limits of freshness for grass carp. Additionally, the effects of PFB and the optimized thermoultrasound-assisted PFB decontamination were mild on the microstructure of grass carp with slight ruptures and loose myofibril structures, indicating the potential of thermoultrasound-assisted PFB for seafood products decontamination with reduced processing time.


Assuntos
Carpas/microbiologia , Gases em Plasma/química , Gases em Plasma/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Shewanella putrefaciens/efeitos dos fármacos , Temperatura , Ondas Ultrassônicas , Animais , Tampões (Química) , Microbiologia de Alimentos , Viabilidade Microbiana/efeitos dos fármacos , Salmonella typhimurium/fisiologia , Shewanella putrefaciens/fisiologia
8.
Microbiol Res ; 250: 126801, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34139525

RESUMO

Bacillus amyloliquefaciens X030 (BaX030) has broad-spectrum antibacterial activity against the fish pathogens Aeromonas hydrophila and Aeromonas veronii. To improve its antibacterial effect, BaX030 was subjected to compound mutagenesis of atmospheric and room temperature plasma (ARTP) and nitrosoguanidine (NTG). The results showed that, compared with the original strain, the production of macrolactin A and oxydifficidin in mutated strain N-11 increased to 39 % and 268 %, respectively. The re-sequencing analysis suggested that there were SNPs and InDels in the gene clusters focused on the sucrose utilization pathway, glycolysis pathway and fatty acid synthesis pathway. Scanning electron microscopy revealed that strain N-11 became thin and long. The qRT-PCR results indicated that the expression of immune factors in the liver or kidney tissue of grass carp increased after feeding with N-11. H&E staining and protection experiments also showed that the mortality and surface symptoms of grass carp infected by the two pathogens were significantly reduced. The study identified a probiotic strain with potential application value in aquaculture production and provided a new strategy for the discovery of new strains with higher antibacterial biological activity.


Assuntos
Aeromonas hydrophila/fisiologia , Aeromonas veronii/fisiologia , Bacillus amyloliquefaciens/genética , Carpas/microbiologia , Interações Microbianas/genética , Mutação , Probióticos , Animais , Bacillus amyloliquefaciens/fisiologia , Doenças dos Peixes/microbiologia
9.
PLoS One ; 16(4): e0248537, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33886562

RESUMO

In the aquaculture sector, a strategy for the more efficient use of resources and proper disease control is needed to overcome the challenges of meat production worldwide. Modulation of the gastrointestinal tract microbiota is a promising approach for promoting animal health and preventing infection. This feeding experiment was conducted to discover the phytonutrient-induced changes in the gastrointestinal tract microbiota of common carp (Cyprinus carpio). Acclimatized animals aged 7 months (30 weeks) were divided randomly into five experimental groups to investigate the effects of the applied feed additives. The dietary supplements were manufactured from anthocyanin-containing processing wastes from the food industry, specifically the production of Hungarian sour cherry extract, synbiotics from fermented corn, and fermentable oligosaccharides from Hungarian sweet red pepper seeds and carotenoids from Hungarian sweet red pepper pulps, applied at a dose of 1%. The gut contents of the animals were collected at four time points throughout the 6-week study period. To track the compositional and diversity changes in the microbiota of the carp intestinal tract, V3-V4 16S rRNA gene-based metagenomic sequencing was performed. The growth performance of common carp juveniles was not significantly affected by supplementation of the basal diet with plant extracts. Phytonutrients improve the community diversity, increase the Clostridium and Lactobacillus abundances and decrease the abundances of potentially pathogenic and spoilage bacteria, such as Shewanella, Pseudomonas, Acinetobacter and Aeromonas. The phyla Proteobacteria, Tenericutes and Chlamydiae were positively correlated with the body weight, whereas Spirochaetes and Firmicutes exhibited negatively correlations with the body weight. We hypothesize that the application of phytonutrients in aquaculture settings might be a reasonable green approach for easing the usage of antibiotics.


Assuntos
Ração Animal , Carpas/microbiologia , Suplementos Nutricionais , Compostos Fitoquímicos , Ração Animal/análise , Animais , Aquicultura , Suplementos Nutricionais/análise , Microbioma Gastrointestinal , Intestinos/microbiologia , Compostos Fitoquímicos/análise
10.
Int J Mol Sci ; 22(8)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33924078

RESUMO

In the present work, we performed immunochemical studies of LPS, especially the O-specific polysaccharide (O-PS) of Aeromonas veronii bv. sobria strain K133, which was isolated from the kidney of carp (Cyprinus carpio L.) during an outbreak of motile aeromonad infection/motile aeromonad septicemia (MAI/MAS) on a Polish fish farm. The structural characterization of the O-PS, which was obtained by mild acid degradation of the LPS, was performed with chemical methods, MALDI-TOF mass spectrometry, and 1H and 13C NMR spectroscopy. It was revealed that the O-PS has a unique composition of a linear tetrasaccharide repeating unit and contains a rarely occurring sugar 2,4-diamino-2,4,6-trideoxy-D-glucose (bacillosamine), which may determine the specificity of the serogroup. Western blotting and ELISA confirmed that A. veronii bv. sobria strain K133 belongs to the new serogroup PGO1, which is one of the most commonly represented immunotypes among carp and trout isolates of Aeromonas sp. in Polish aquacultures. Considering the increase in the MAI/MAS incidences and their impact on freshwater species, also with economic importance, and in the absence of an effective immunoprophylaxis, studies of the Aeromonas O-antigens are relevant in the light of epidemiological data and monitoring emergent pathogens representing unknown antigenic variants and serotypes.


Assuntos
Aeromonas veronii/química , Carpas/microbiologia , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , Lipopolissacarídeos/química , Aeromonas veronii/classificação , Aeromonas veronii/isolamento & purificação , Animais , Animais Domésticos , Doenças dos Peixes/imunologia , Lipopolissacarídeos/imunologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Polônia , Sorogrupo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
11.
Food Microbiol ; 98: 103686, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875196

RESUMO

This study aimed to achieve deeper insights into the microbiota composition and dynamic succession of the dry-cured black carp during storage using a high-throughput sequencing technique (HTS). The effect of lipid oxidation on microorganisms was also evaluated. Over 651 bacterial genera belonging to 37 phyla were identified. Firmicutes, Proteobacteria and Actinobacteria were the main bacterial phylum, some are highly associated with meat spoilage. Staphylococcus, Macrococcus and Acinetobacter were the most three microbial genera throughout the entire storage period (30 days). Between two different storage temperature, refrigeration at 4 °C could facilitate maintaining the microbial diversity, while 25 °C storage led to the formation of dominant microflora and the reduction of community diversity. Canonical correspondence analysis (CCA) showed that acid value (AV), malondialdehyde (MDA) and 4-hydroxy-2-hexenal (HHE) contents were three key environmental factors (oxidation products) affecting the profile of the microbiota. Staphylococcus presented a positive correlation with HHE content, while Macrococcus and Acinetobacter were negatively correlated with HHE content. These results could expand our knowledge on the effect of lipid oxidation on change of microbial distribution, it could also present an guideline to develop advanced storage methods for the vacuum packed dry-cured fish products.


Assuntos
Bactérias/isolamento & purificação , Produtos Pesqueiros/microbiologia , Lipídeos/química , Microbiota , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Biodiversidade , Carpas/microbiologia , Produtos Pesqueiros/análise , Microbiologia de Alimentos , Embalagem de Alimentos/instrumentação , Embalagem de Alimentos/métodos , Armazenamento de Alimentos , Sequenciamento de Nucleotídeos em Larga Escala , Oxirredução , Refrigeração , Vácuo
12.
Fitoterapia ; 151: 104884, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33766742

RESUMO

Two new 14-membered resorcylic acid lactone derivatives, ascarpins A (1) and B (2), together with three related known compounds (3-5) were isolated from the fungus Aspergillus sp. ZJ-65, obtaining from the intestine of grass carp. These structures were elucidated on the basis of extensive spectroscopic methods, chemical conversion, and comparison with literature. All isolates were tested for their inhibitory activity against LPS-induced NO production in RAW 264.7 macrophages. Among them, compounds 1-4 exhibited potential anti-inflammatory activity with IC50 values ranging from 7.6 to 48.3 µM.


Assuntos
Anti-Inflamatórios/farmacologia , Aspergillus/química , Carpas/microbiologia , Lactonas/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , China , Lactonas/isolamento & purificação , Camundongos , Estrutura Molecular , Óxido Nítrico , Células RAW 264.7
13.
Vet Res ; 52(1): 18, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33579339

RESUMO

This study reports the comparative analyses of four Flavobacterium columnare isolates that have different virulence and antimicrobial resistance patterns. The main research goal was to reveal new insights into possible virulence genes by comparing the genomes of bacterial isolates that could induce tissue damage and mortality versus the genome of a non-virulent isolate. The results indicated that only the genomes of the virulent isolates possessed unique genes encoding amongst others a methyl-accepting chemotaxis protein possibly involved in the initial colonization of tissue, and several VgrG proteins engaged in interbacterial competition. Furthermore, comparisons of genes unique for the genomes of the highly virulent (HV) carp and trout isolates versus the, respectively, low and non-virulent carp and trout isolates were performed. An important part of the identified unique virulence genes of the HV-trout isolate was located in one particular gene region identified as a genomic island. This region contained araC and nodT genes, both linked to pathogenic and multidrug-resistance, and a luxR-gene, functional in bacterial cell-to-cell communication. Furthermore, the genome of the HV-trout isolate possessed unique sugar-transferases possibly important in bacterial adhesion. The second research goal was to obtain insights into the genetic basis of acquired antimicrobial resistance. Several point-mutations were discovered in gyrase-genes of an isolate showing phenotypic resistance towards first and second-generation quinolones, which were absent in isolates susceptible to quinolones. Tetracycline-resistance gene tetA was found in an isolate displaying acquired phenotypic resistance towards oxytetracycline. Although not localized on a prophage, several flanking genes were indicative of the gene's mobile character.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Flavobacterium/genética , Animais , Carpas/microbiologia , Flavobacterium/efeitos dos fármacos , Flavobacterium/patogenicidade , Genômica , Truta/microbiologia , Virulência
14.
Artigo em Inglês | MEDLINE | ID: mdl-33465759

RESUMO

The intestinal microbiome plays a pivotal role in the nutritional digestion and metabolism of the grass carp (Ctenopharyngodon idella). Here, we characterized the digesta and mucosal microbiome of the anterior, middle, and posterior intestine of the grass carp, using 16S rRNA next-generation sequencing. Based on 16S rRNA amplicon data, Proteobacteria, Firmicutes and Bacteroides were the dominant phyla in the intestine of grass carp. Our results also showed that microbial communities of the middle intestine exhibited higher alpha diversity indices compared with the anterior and posterior intestine. The clustering of microbial communities that had either colonized in the digesta or were attached to the mucosa, were significantly tighter in the posterior intestine, based on average unweighted Unifrac distances (P < 0.05). The digesta or mucosa of the anterior and middle intestines were similar in microbial composition, but were significantly different to the posterior intestine (P < 0.05). In digesta and mucosa samples from the posterior intestine, we observed a significantly increased abundance of cellulose-degrading microbiomes, such as Bacteroides, Clostridiales and Spirochaetia (P < 0.05). Our results suggested that the microbiomes of the posterior intestine, either attached to the mucosa or colonized in the digesta, were distinct from the microbiomes of the anterior and middle intestine in grass carp.


Assuntos
Carpas/microbiologia , Microbioma Gastrointestinal , Animais , Bactérias/isolamento & purificação , Bacteroides/isolamento & purificação , Firmicutes/isolamento & purificação , Mucosa Intestinal/microbiologia , Intestinos/microbiologia , Proteobactérias/isolamento & purificação
15.
Carbohydr Res ; 500: 108210, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33298315

RESUMO

The O-specific polysaccharide (OPS) was isolated from the lipopolysaccharide of Aeromonas veronii strain Bs8, which is pathogenic to common carp (Cyprinus carpio), after mild acid hydrolysis followed by gel-permeation chromatography. The high-molecular-mass OPS fraction was investigated using chemical methods, mass spectrometry, and 1H and 13C NMR spectroscopy techniques, including 2D homonuclear 1H,1H TOCSY, DQF COSY, NOESY, and heteronuclear 1H-detected 1H,13C HSQC, and HMBC experiments. The analysis revealed that the O-specific polysaccharide contains sugars with the galacto configuration of the ring and is composed of a disaccharide repeating unit with the following structure.


Assuntos
Aeromonas veronii/química , Dissacarídeos/química , Polissacarídeos/isolamento & purificação , Animais , Configuração de Carboidratos , Carpas/microbiologia , Polissacarídeos/química
16.
Environ Microbiol ; 23(1): 431-447, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33201573

RESUMO

Gut microbiota could facilitate host to defense diseases, but fish-microbiota interactions during viral infection and the underlying mechanism are poorly understood. We examined interactions and responses of gut microbiota to grass carp reovirus (GCRV) infection in Ctenopharyngodon idellus, which is the most important aquaculture fish worldwide. We found that GCRV infection group with serious haemorrhagic symptoms (G7s) showed considerably different gut microbiota, especially with an abnormally high abundance of gram-negative anaerobic Cetobacterium somerae. It also showed the lowest (p < 0.05) alpha-diversity but with much higher ecological process of homogenizing dispersal (28.8%), confirming a dysbiosis of the gut microbiota after viral infection. Interestingly, signaling pathways of NOD-like receptors (NLRs), toll-like receptors (TLRs), and lipopolysaccharide (LPS) stimulation genes were significantly (q-value < 0.01) enriched in G7s, which also significantly (p < 0.01) correlated with the core gut microbial genera of Cetobacterium and Acinetobacter. The results suggested that an expansion of C. somerae initiated by GCRV could aggravate host inflammatory reactions through the LPS-related NLRs and TLRs pathways. This study advances our understanding of the interplay between fish immunity and gut microbiota challenged by viruses; it also sheds new insights for ecological defense of fish diseases with the help of gut microbiota.


Assuntos
Carpas/microbiologia , Carpas/virologia , Doenças dos Peixes/virologia , Microbioma Gastrointestinal , Orthoreovirus Mamífero 3/fisiologia , Infecções por Reoviridae/veterinária , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Doenças dos Peixes/microbiologia , Fusobactérias , Interações Hospedeiro-Patógeno , Orthoreovirus Mamífero 3/classificação , Orthoreovirus Mamífero 3/genética , Orthoreovirus Mamífero 3/isolamento & purificação , Infecções por Reoviridae/microbiologia , Infecções por Reoviridae/virologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-32828913

RESUMO

Lead is an environmental toxicant that has toxicity effect to the health of aquatic organisms. Gut microbiota has been reported to be closely related to human health. The aim of this study was to investigate the effects of lead exposure on the composition of gut microbiota. The composition of gut microbiota alteration was detected by 16S rRNA gene sequencing, following a 42-day exposure of lead (1 mg/L). The results showed that compared with the normal control group, the carp of lead group showed severe intestinal tissues injury and decreased Zona Occludens 1 (ZO-1) and occludin expression. The production of LPS in serum was increased by the treatment of lead exposure. Our results showed gut bacterial diversity in lead-treated common carp was lower than the control group. At the phylum level, the abundance of Bacteroidetes (LPS producing bacteria) and Fusobacteria in lead-treated carp were much higher than the control carp. And the abundance of Actinobacteria decreased by lead exposure. At the genus level, we found the abundance of Bacteroides (LPS producing bacteria) and Plesiomonas (an important pathogenic bacteria), increased significantly by lead exposure. And the abundance of Akkermansia, a critical probiotics, was markedly inhibited by lead exposure. In conclusion, this study indicated exposure of carp to lead causes gut microbiota alterations and intestinal structural integrity destruction.


Assuntos
Carpas/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Chumbo/toxicidade , Animais
18.
Virulence ; 12(1): 165-176, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33372840

RESUMO

Aeromonas hydrophila (A. hydrophila) can cause a number of diseases in both human and animals. A. hydrophila-related infections in aquaculture cause severe economic losses every year throughout the world. The emergence of antibiotic resistance that is due to the abuse of antibiotics has limited the application of antibiotics. Thus, novel approaches are needed to combat with treatment failure of antibiotics caused by resistant bacterial strains. Aerolysin plays a critical role in the pathogenesis of A. hydrophila and has been considered as a novel target for developing drugs based on anti-virulence strategies. Here, we reported that luteolin, a natural product with no anti-A. hydrophila activity, could reduce aerolysin-induced hemolysis by inhibiting aerolysin activity. The binding mode was simulated by molecular docking and dynamics simulation. Then the main binding sites were confirmed by fluorescence quenching assays. We found that luteolin could hindered the formation of functional heptamer of aerolysin according to the results of the oligomerization assay. Moreover, luteolin could protect A549 cells from aerolysin mediated cell death and increase the survival rate of A. hydrophila-infected channel catfish. These findings suggest a novel approach to developing drugs fighting against A. hydrophila, and luteolin can be a promising drug candidate for treatment of A. hydrophila-associated infections.


Assuntos
Aeromonas hydrophila/efeitos dos fármacos , Aeromonas hydrophila/patogenicidade , Toxinas Bacterianas/antagonistas & inibidores , Toxinas Bacterianas/metabolismo , Luteolina/metabolismo , Luteolina/farmacologia , Proteínas Citotóxicas Formadoras de Poros/antagonistas & inibidores , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Células A549 , Animais , Produtos Biológicos/metabolismo , Carpas/microbiologia , Doenças dos Peixes/tratamento farmacológico , Doenças dos Peixes/microbiologia , Humanos , Simulação de Acoplamento Molecular , Virulência
19.
Food Chem ; 345: 128862, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33338838

RESUMO

Effects of ultrasound-assisted chitooligosaccharides (COS-UA) coating on the quality attributes and microbial composition of refrigerated grass carp fillets were evaluated. The results showed that COS and COS-UA coatings retarded quality deterioration of fillets during storage. Compared to COS coatings, COS-UA treated samples had lower contents of BAs, simultaneously their levels of total volatile base nitrogen (TVB-N), K value and total viable counts (TVC) were further decreased by 13.6%, 4.2% and 7.8% on day 12, respectively. High-throughput sequencing showed that Aeromonas and Shewanella increased rapidly in control samples and became the main microbiota at day 12. By contrast, both coatings changed the microbial composition and reduced the proportion of spoilage organisms. Based on multiple evaluations, COS-UA extended shelf life of fillets by another 2 days when compared to COS. Therefore, ultrasonic treatment could be considered as an effective supplementary to improve the preservation effect of COS-based coatings for fresh preprocessed fish.


Assuntos
Carpas , Conservação de Alimentos/métodos , Armazenamento de Alimentos/métodos , Alimentos Marinhos , Ondas Ultrassônicas , Animais , Carpas/microbiologia , Microbiota
20.
Food Chem ; 336: 127683, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32771900

RESUMO

This study aimed to reveal amino acid deamination and decarboxylation activities of spoilage microbiota in chill-stored grass carp fillets. Results showed that microbial deamination activities of umami/sweet-taste amino acids were higher than that of bitter-taste amino acids. The total deamination activity of tested amino acids decreased during the late period of storage, which inhibited the increase of ammonia in fish flesh. Microbial decarboxylation activity of ornithine was much higher than lysine and histidine, which was consistent with the rapid increase of putrescine in fish fillets. Meanwhile, putrescine could be produced in large quantities through arginine deiminase pathway of spoilage bacteria. Glucose utilization by spoilage microbiota was active during the late period of storage, which was consistent with the rapid consumption of lactate and total sugar in fish flesh. Overall, results of this study could be beneficial for revealing fish spoilage mechanisms and providing theoretical guidance for developing fish preservation technologies.


Assuntos
Aminoácidos/metabolismo , Carpas/metabolismo , Carpas/microbiologia , Temperatura Baixa , Armazenamento de Alimentos , Microbiota , Animais , Bactérias/metabolismo , Desaminação , Descarboxilação , Paladar
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