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1.
J Med Microbiol ; 70(8)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34397349

RESUMO

Introduction. Lactococcus petauri LZys1 (L. petauri LZys1) is a type of lactic acid bacteria (LAB), which was initially isolated from healthy human gut.Hypothesis/Gap Statement. It was previously anticipated that L. petauri LZys1 has potential characteristics of probiotic properties. The genetic structure and the regulation functions of L. petauri LZys1 need to be better revealed.Aim. The aim of this study was to detect the probiotic properties L. petauri LZys1 and to reveal the genome information related to its genetic adaptation and probiotic profiles.Methodology. Multiple in vitro experiments were carried out to evaluate its lactic acid-producing ability, resistance to pathogenic bacterial strains, auto-aggregation and co-aggregation ability, and so on. Additionally, complete genome sequencing, gene annotation, and probiotic associated gene analysis were performed.Results. The complete genome of L. petauri LZys1 comprised of 1 985 765 bp, with a DNA G+C content of 38.07 %, containing 50 tRNA, seven rRNA, and four sRNA. A total of 1931 genes were classified into six functional categories by Kyoto Encyclopaedia of Genes and Genomes (KEGG) database. The neighbour-joining phylogeny tree based on the whole genome of L. petauri LZys1 and other probiotics demonstrated that L. petauri LZys1 has a significant similarity to Lactococcus garvieae. The functional genes were detected to expound the molecular mechanism and biochemical processes of its potential probiotic properties, such as atpB gene.Conclusion. All the results described in this study, together with relevant information previously reported, made L. prtauri LZys1 a very interesting potential strain to be considered as a prominent candidate for probiotic use.


Assuntos
Trato Gastrointestinal/microbiologia , Genoma Bacteriano , Lactococcus , Probióticos , Animais , Bactérias/crescimento & desenvolvimento , Bactérias/patogenicidade , Sequência de Bases , Fezes/microbiologia , Genes Bacterianos , Humanos , Lactococcus/citologia , Lactococcus/genética , Lactococcus/isolamento & purificação , Lactococcus/fisiologia , Masculino , Anotação de Sequência Molecular , Mariposas/microbiologia , Filogenia , Polissacarídeos Bacterianos/biossíntese , Polissacarídeos Bacterianos/genética , Sequenciamento Completo do Genoma , Adulto Jovem
2.
Molecules ; 26(16)2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34443691

RESUMO

BACKGROUND: Milk is considered an important source of bioactive peptides, which can be produced by endogenous or starter bacteria, such as lactic acid bacteria, that are considered effective and safe producers of food-grade bioactive peptides. Among the various types of milk, donkey milk has been gaining more and more attention for its nutraceutical properties. METHODS: Lactobacillus rhamnosus 17D10 and Lactococcus lactis subsp. cremoris 40FEL3 were selected for their ability to produce peptides from donkey milk. The endogenous peptides and those obtained after bacterial fermentation were assayed for their antioxidant, antibacterial, and antiviral activities. The peptide mixtures were characterized by means of LC-MS/MS and then analyzed in silico using the Milk Bioactive Peptide DataBase. RESULTS: The peptides produced by the two selected bacteria enhanced the antioxidant activity and reduced E. coli growth. Only the peptides produced by L. rhamnosus 17D10 were able to reduce S. aureus growth. All the peptide mixtures were able to inhibit the replication of HSV-1 by more than 50%. Seventeen peptides were found to have 60% sequence similarity with already known bioactive peptides. CONCLUSIONS: A lactic acid bacterium fermentation process is able to enhance the value of donkey milk through bioactivities that are important for human health.


Assuntos
Antibacterianos/farmacologia , Antivirais/farmacologia , Fermentação , Lactobacillus rhamnosus/fisiologia , Lactococcus/fisiologia , Leite/microbiologia , Sequência de Aminoácidos , Animais , Antioxidantes/farmacologia , Quelantes/farmacologia , Equidae , Proteínas do Leite/análise , Peptídeos/química , Peptídeos/farmacologia
3.
Microbiol Res ; 248: 126751, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33839507

RESUMO

In this study, the seed endosphere of a bacterial wilt tolerant chilli cv. Firingi Jolokia was explored in order to find effective agents for bacterial wilt disease biocontrol. A total of 32 endophytic bacteria were isolated from freshly collected seeds and six isolates were selected based on R. solanacearum inhibition assay. These isolates were identified as Bacillus subtilis (KJ-2), Bacillus velezensis (KJ-4), Leuconostoc mesenteroides (KP-1), Lactococcus lactis (LB-3), Bacillus amyloliquefaciens (WK-2), and Bacillus subtilis (WK-3) by 16S rRNA gene sequencing. In the in planta R. solanacearum inhibition assay carried out by seedling root bacterization method, Bacillus subtilis (KJ-2) exhibited highest biocontrol efficacy of 86.6 % on 7th day post R. solanacearum inoculation and a minimum biocontrol efficacy of 52.9 % was noted for Leuconostoc mesenteroides (KP-1). GC-HRMS analysis detected several known antimicrobial compounds in the extract of the culture supernatant of Bacillus subtilis (KJ-2); which may contribute to inhibition of R. solanacearum. In the growth promotion assay conducted using these isolates, only two of them namely Bacillus subtilis (KJ-2) and Bacillus amyloliquefaciens (WK-2) showed growth promotion in true leafed tomato plants. All the selected seed endophytic isolates were able to control bacterial wilt of tomato at the seedling stage and Bacillus subtilis (KJ-2) was found to be most effective in controlling the disease. The results of the present study highlighted that seed endosphere of bacterial wilt tolerant cultivar is a rich source of R. solanacearum antagonizing bacterial isolates.


Assuntos
Antibiose , Bacillus/fisiologia , Capsicum/microbiologia , Proteção de Cultivos/métodos , Endófitos/fisiologia , Lactococcus/fisiologia , Doenças das Plantas/prevenção & controle , Bacillus/classificação , Bacillus/genética , Bacillus/isolamento & purificação , Endófitos/classificação , Endófitos/genética , Endófitos/isolamento & purificação , Lactococcus/classificação , Lactococcus/genética , Lactococcus/isolamento & purificação , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/microbiologia , Doenças das Plantas/microbiologia , Ralstonia solanacearum/fisiologia , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Sementes/microbiologia
4.
J Fish Dis ; 44(6): 721-727, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33522610

RESUMO

The pathogenesis of Lactococcus garvieae (L. garvieae) was assessed in Nile tilapia (Oreochromis niloticus) following administration by two different routes of infection (intraperitoneal versus immersion), using 180 fish divided into three groups. The first group of fish was injected intraperitoneally (IP) with 3 × 105 colony-forming units (cfu) of L. garvieae; the second group was infected by immersion (IMM) into water containing 9.6 × 105  cfu/ml L. garvieae, and in group 3 (Control), the fish were injected IP with sterile normal saline. Mortalities were recorded daily, and on 3, 5, 7, and 13 days post-infection (dpi), liver, kidney, spleen, brain and eyes were sampled. The level of infection between groups was assessed by number of mortalities that occurred, pathology/histopathology of internal organs, bacterial re-isolation and presence of bacteria in situ determined using immunohistochemistry. A significant difference (p < .0001) was observed between L. garvieae re-isolation from tilapia following administration by IP injection and IMM. Similarly, more clinical signs and mortalities (p < .001) were observed in the IP group compared to the IMM group where no mortalities were observed. These findings suggest that L. garvieae has a low invasive potential in Nile tilapia with intact skin/external barriers and highlights the importance of maintaining fish without cuts or abrasions under field conditions.


Assuntos
Ciclídeos , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Positivas/veterinária , Lactococcus/fisiologia , Animais , Infecções por Bactérias Gram-Positivas/microbiologia , Lagos , Zâmbia
5.
Nutrients ; 12(11)2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33121026

RESUMO

Lactic acid bacteria (LAB), a major commensal bacterium in the small intestine, are well known beneficial bacteria which promote establishment of gut-centric immunity, such as anti-inflammation and anti-infection. In this report, we show that a LAB strain Lactococcus lactis subsp. Cremoris C60 possess an ability to activate antigen presenting cells, such as dendritic cells (DCs), and intestinal T cells which possibly support to maintain healthy intestinal immunological environment in aging process. We found that CD4+ T cells in the small intestine are dramatically decreased in aged Interleukin-18 knock out (IL-18KO) mice, associated with the impairment of IFN-γ production in the CD4+ T cells, especially in small intestinal lamina propria (LP). Surprisingly, heat killed-C60 (HK-C60) diet completely recovered the CD4+ T cells population and activity in SI-LP and over activated the population in Peyer's patches (PPs) of IL-18KO mice. The HK-C60 diet was effective approach not only to restore the number of cells, but also to recover IFN-γ production in the CD4+ T cell population in the small intestine of IL-18-deficient mice. As a possible cause in the age-associated impairment of CD4+ T cells activity in IL-18KO mice, we found that the immunological activity was downregulated in the IL-18-deficient DCs. The cytokines production and cellular activation markers expression were downregulated in the IL-18-deficient bone marrow derived dendritic cells (BMDCs) at the basal level, however, both activities were highly upregulated in HK-C60 stimulation as compared to those of WT cells. Antigen uptake was also attenuated in the IL-18-deficient BMDCs, and it was significantly enhanced in the cells as compared to WT cells in HK-60 stimulation. An in vitro antigen presentation assay showed that IFN-γ production in the CD4+ T cells was significantly enhanced in the culture of IL-18-deficient BMDCs compared with WT cells in the presence of HK-C60. Thus, we conclude that HK-C60 diet possesses an ability to restore T cells impairment in the small intestine of IL-18-deficient environment. In addition, the positive effect is based on the immunological modification of DCs function which directory influences into the promotion of effector CD4+ T cells generation in the small intestine.


Assuntos
Interleucina-18/deficiência , Intestino Delgado/imunologia , Lactococcus/fisiologia , Probióticos/administração & dosagem , Linfócitos T/imunologia , Envelhecimento , Animais , Linfócitos T CD4-Positivos , Contagem de Células , Células Dendríticas/imunologia , Dieta , Interferon gama/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Membrana Mucosa/imunologia , Linfócitos T/citologia
6.
Sci Rep ; 10(1): 14525, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32884012

RESUMO

Kawasaki disease (KD) is a multi-systemic vasculitis of unknown etiology that occurs mainly in children, and the disturbance of gut microbiota is generally believed to cause a hyperimmune reaction triggering KD. The aim of the study was to investigate the alterations in the fecal microbiota and assess its relationship with systemic inflammation. Totally 30 KD children were enrolled and followed up for 6 months, with another group of 30 age- and sex-matched healthy children as controls. Phylotype profiles of fecal microbial communities were analyzed using 16S rRNA gene sequencing. Serum inflammatory markers were detected by flow cytometer. We showed that KD children exhibited a significant reduction in fecal microbial diversity in the acute phase compared with the healthy controls. Enterococcus, Acinetobacter, Helicobacter, Lactococcus, Staphylococcus and Butyricimonas in acute KD children were significantly higher than the healthy children. Levels of systemic inflammation biomarkers, including IL-2, IL-4, IL-6, IL-10, TNF-α, and INF-γ, were significantly elevated in the acute KD children. Altered microbiota genera Enterococcus and Helicobacter abundances were shown to be correlated positively with IL-6, which were never previously reported in KD. This study suggested that gut microbiota alteration is closely associated with systemic inflammation, which provides a new perspective on the etiology and pathogenesis of KD.


Assuntos
Inflamação/imunologia , Inflamação/microbiologia , Síndrome de Linfonodos Mucocutâneos/imunologia , Síndrome de Linfonodos Mucocutâneos/microbiologia , Acinetobacter/fisiologia , Pré-Escolar , Biologia Computacional , Enterococcus/fisiologia , Feminino , Microbioma Gastrointestinal/fisiologia , Helicobacter/fisiologia , Humanos , Lactente , Inflamação/metabolismo , Lactococcus/fisiologia , Masculino , Síndrome de Linfonodos Mucocutâneos/metabolismo , Reação em Cadeia da Polimerase , Staphylococcus/fisiologia
7.
J Dairy Sci ; 103(11): 9803-9814, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32896398

RESUMO

Obesity, which has become a major public health problem, can arise from complex dyslipidemia, insulin resistance, and immune responses, among other mechanisms. Some Lactobacillus strains effectively ameliorate obesity; however, the beneficial effects of Lactococcus spp., which are often used as dairy starters, remain unclear. In the present study, we evaluated the efficacy of Lactococcus chungangensis CAU 28 using the 3T3-L1 cell line and obese mice fed a high-fat diet. Overall, administration of Lc. chungangensis CAU 28 effectively resolved obesity associated with weight gain and lipid accumulation. In differentiated 3T3-L1 cells, Lc. chungangensis CAU 28 treatment significantly diminished the total lipid quantity, inhibited triglyceride formation, and prevented the proliferation of adipogenic transcription factors (fatty acid synthase, adiponectin, peroxisome proliferator-activated receptor-gamma, and CCAAT-enhancer-binding protein-α) associated with lipid accumulation. In the obesity mouse model, wherein the intake of Lc. chungangensis CAU 28 effectively reduced body weight gain, along with fat differentiation and accumulation (white fat; abdominal and subcutaneous). Furthermore, Lc. chungangensis CAU 28 increased serum adiponectin levels, decreased serum leptin levels, and effectively regulated adipokine secretion. It also increased the high-density lipoprotein:cholesterol ratio, reduced total cholesterol and triglyceride levels, reduced the low-density lipoprotein:cholesterol ratio, and affected obesity-regulated inflammatory cytokines IL-6, tumor necrosis factor-α, IFN-γ, and IL-1ß. Additionally, Lc. chungangensis CAU 28 was associated with an increase in the CD3+CD4+CD8- phenotype among obese mice. Thus, the administration of Lc. chungangensis CAU 28 induced antiobesity effects, suggesting potential applications of this species as a supplement for obesity mitigation.


Assuntos
Tecido Adiposo/metabolismo , Dieta Hiperlipídica , Lactococcus/fisiologia , Obesidade/prevenção & controle , Células 3T3-L1 , Adipogenia , Adiponectina/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Lactococcus/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/veterinária , PPAR gama/metabolismo , Ganho de Peso/efeitos dos fármacos
8.
Fish Shellfish Immunol ; 105: 457-468, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32673645

RESUMO

Lactococcosis is one of the main bacterial diseases affecting rainbow trout (Oncorhynchus mykiss), with significant economic and sanitary repercussion. Vaccination and antibiotic treatments are commonly used to prevent and control the infection outbreaks; however, these strategies have some drawbacks including limited coverage, handling costs, induction of antibiotic resistance and chemical residues in the environment. Selective breeding programs represent a promising complementary approach for increasing fish disease resistance in commercial farms and some immunological parameters may be tentatively used as indirect indicators for this purpose. The present study investigated for the first time some innate and adaptive immune responses in two groups of rainbow trout derived from selected lines (susceptible and resistant) showing a different "in field" phenotypical resistance to Yersinia ruckeri, Flavobacterium branchiophilum, F. psychrophilum, and Ichthyophthirius multifiliis, after an immersion-dilution based exposure to Lactococcus garvieae carried out in controlled experimental conditions. Twenty-six resistant and twenty-six susceptible female rainbow trout (mean body weight 80 g, 9 months aged, F5 generation) were obtained from an intensive farm considered L. garvieae free and were exposed to the pathogen. Moreover, 10 resistant and 10 susceptible fish were used as uninfected controls. After 5 days, blood and tissue samples were collected for immunological analyses. A significantly higher serum and mucus lysozyme activity was recorded in resistant rainbow trout compared to susceptible fish (P ≤ 0.05), both before and after exposure to L. garvieae. Similarly, respiratory burst activity of head kidney leukocytes resulted more intense in resistant fish (P ≤ 0.05), suggesting that phagocytes could more quickly activate their microbicidal mechanisms to counteract the bacterial spread. Resistant group displayed also an up-regulation of immunoglobulins M (IgM), major histocompatibility complex II (MHC-II) and interleukin 8 (IL-8) gene expression (P ≤ 0.05) and a significantly higher blood lymphocytes count (P ≤ 0.05), highlighting their potential better ability to trigger the recruitment of defensive cells and the initiation of specific immune processes such as antigen presentation to CD4+ T lymphocytes and IgM synthesis. The results herein presented might be useful for the identification of immunological markers to be used as indirect indicators in rainbow trout selective breeding programs.


Assuntos
Resistência à Doença/imunologia , Suscetibilidade a Doenças/veterinária , Doenças dos Peixes/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Imunidade Inata , Oncorhynchus mykiss , Imunidade Adaptativa , Animais , Suscetibilidade a Doenças/imunologia , Suscetibilidade a Doenças/microbiologia , Doenças dos Peixes/microbiologia , Flavobacterium/fisiologia , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/microbiologia , Hymenostomatida/fisiologia , Lactococcus/fisiologia , Yersinia ruckeri/fisiologia
9.
Acta Vet Scand ; 62(1): 38, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32611367

RESUMO

Growing global concerns about antibiotic resistance have generated a considerable interest in the search for alternative environmental-friendly approaches. This study was aimed to assess the antimicrobial activity of a multi-citrus extract-based feed additive (Biocitro®) against some fish pathogens, as well as evaluate its capacity to protect rainbow trout (Oncorhynchus mykiss) to lactococcosis. A broth dilution method was used to determine the minimum inhibitory concentration (MIC) of Biocitro®, and the results showed a strong antibacterial activity against Aeromonas salmonicida, Lactococcus garvieae and Yersinia ruckeri with MIC values of 2.0 µg/mL. Afterwards, rainbow trout juveniles were fed a Biocitro®-enriched diet (750 mg/kg feed) at a daily rate of 1.5% body weight for 4 weeks, then they were challenged with L. garvieae by the cohabitation method. At the end of the experimental period, fish treated with Biocitro® showed significantly (P < 0.001) improved protection against L. garvieae compared to control fish. Although further studies are needed to understand how Biocitro® increases rainbow trout resistance to L. garvieae, this feed additive could be considered as a useful alternative to chemotherapeutic treatment in aquaculture.


Assuntos
Citrus/química , Doenças dos Peixes/imunologia , Oncorhynchus mykiss/imunologia , Extratos Vegetais/metabolismo , Aeromonas salmonicida/fisiologia , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Lactococcus/fisiologia , Extratos Vegetais/administração & dosagem , Distribuição Aleatória , Yersiniose/imunologia , Yersiniose/veterinária , Yersinia ruckeri/fisiologia
10.
Arch Microbiol ; 202(8): 2059-2069, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32488559

RESUMO

The dynamic changes of microbiota assessed by high-throughput sequencing and texture properties of handmade cheese were investigated during ripening time. Streptococcus and Lactococcus were found to be the most predominant genera. The proportion of Streptococcus was decreased from 48 to 32% and the proportion of Lactococcus was increased from 41 to 55% with ripening time from 1 to 120 days. Mould and yeast such as Paecilomyces, Candida, Issatchenkia, Rhodotorula, Cryptococcus and Trichosporon were observed. The regression analysis between composition and textural properties indicated that the hardness was increased along with the rising of soluble nitrogen, while the increased soluble nitrogen could result in lower cohesiveness, and the increased fat in dry matter resulted in lower resilience. The physic-chemical parameters were correlated with secondary microbiota such as Cryptococcus and Candida according to the multivariate association analysis (p < 0.05). These findings could provide a baseline to improve the product quality and preserve the traditional characteristics of handmade cheese.


Assuntos
Queijo/microbiologia , Microbiologia de Alimentos , Microbiota/fisiologia , Queijo/análise , Queijo/normas , China , Manipulação de Alimentos , Fungos/fisiologia , Lactococcus/fisiologia , Streptococcus/fisiologia
11.
BMC Microbiol ; 20(1): 136, 2020 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-32460704

RESUMO

BACKGROUND: Lactococcus members belonging to lactic acid bacteria are widely used as starter bacteria in the production of fermented dairy products. From kimchi, a Korean food made of fermented vegetables, Lactococcus raffinolactis WiKim0068 was isolated and its genome was analyzed. RESULTS: The complete genome of the strain WiKim0068 consists of one chromosome and two plasmids that comprises 2,292,235 bp, with a G + C content of 39.7 mol%. Analysis of orthoANI values among Lactococcus genome sequences showed that the strain WiKim0068 has > 67% sequence similarity to other species and subspecies. In addition, it displayed no antibiotic resistance and can metabolize nicotinate and nicotinamide (vitamin B3). CONCLUSION: These results augments our understanding of the genus Lactococcus and suggest that this new strain has potential industrial applications.


Assuntos
Lactococcus/classificação , Verduras/microbiologia , Sequenciamento Completo do Genoma/métodos , Composição de Bases , Fermentação , Tamanho do Genoma , Genoma Bacteriano , Lactococcus/isolamento & purificação , Lactococcus/fisiologia , Niacina/metabolismo , Niacinamida/metabolismo , Filogenia , Probióticos/análise
12.
PLoS One ; 15(3): e0230739, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32214386

RESUMO

The autovaccine was produced in-house using a bacterial isolate from a diseased fish from the target farm. Three groups of 150 fish each were injected with either 1) an oil-adjuvanted, inactivated whole cell autovaccine, 2) adjuvant only or 3) PBS (negative control). Approximately 660 degree days post vaccination, the fish were challenged with 9x105 cfu bacteria/fish by intraperitoneal injection and monitored for a further 28 days. Protection against infections was measured by lack of/reduced bacterial loads both by bacterial re-isolation and immunohistochemistry as well as absence of clinical signs/pathology. Significantly less L. garvieae (p<0.03) was re-isolated from either the adjuvant only or control groups compared to the vaccinated group. Furthermore, a significantly high amount (p<0.001) of anti-L. garvieae specific antibodies were observed in the vaccinated group compared to the adjuvant only or control groups at time of challenge. This coincided with protection against infection measured by absence/reduced L. garvieae re-isolation from internal organs, reduced clinical signs and lack of pathology in this group. In the adjuvant only and control groups, bacteria were re-isolated from the kidney, liver, spleen, brain and eyes during the first 14 days. The findings suggest that oil-based vaccines can protect tilapia against L. garvieae infection through an antibody mediated response.


Assuntos
Autovacinas/imunologia , Ciclídeos/imunologia , Ciclídeos/microbiologia , Doenças dos Peixes/prevenção & controle , Lactococcus/fisiologia , Animais , Autopsia , Doenças dos Peixes/patologia , Especificidade de Órgãos
13.
Sci Rep ; 10(1): 2719, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066764

RESUMO

The white leg Litopenaeus vannamei shrimp is of importance to the eastern Pacific fisheries and aquaculture industry but suffer from diseases such as the recently emerged early mortality syndrome. Many bacterial pathogens have been identified but the L. vannamei microbiota is still poorly known. Using a next-generation sequencing (NGS) approach, this work evaluated the impact of the inclusion in the diet of mannan oligosaccharide, (MOS, 0.5% w/w), over the L. vannamei microbiota and production behavior of L. vannamei under intensive cultivation in Ecuador. The MOS supplementation lasted for 60 days, after which the shrimp in the ponds were harvested, and the production data were collected. MOS improved productivity outcomes by increasing shrimp survival by 30%. NGS revealed quantitative differences in the shrimp microbiota between MOS and control conditions. In the treatment with inclusion of dietary MOS, the predominant phylum was Actinobacteria (28%); while the control group was dominated by the phylum Proteobacteria (30%). MOS has also been linked to an increased prevalence of Lactococcus- and Verrucomicrobiaceae-like bacteria. Furthermore, under the treatment of MOS, the prevalence of potential opportunistic pathogens, like Vibrio, Aeromonas, Bergeyella and Shewanella, was negligible. This may be attributable to MOS blocking the adhesion of pathogens to the surfaces of the host tissues. Together, these findings point to the fact that the performance (survival) improvements of the dietary MOS may be linked to the impact on the microbiota, since bacterial lines with pathogenic potential towards shrimps were excluded in the gut.


Assuntos
Actinobacteria/fisiologia , Aquicultura/métodos , Mananas/administração & dosagem , Microbiota , Oligossacarídeos/administração & dosagem , Penaeidae/microbiologia , Actinobacteria/classificação , Actinobacteria/isolamento & purificação , Aeromonas/isolamento & purificação , Aeromonas/patogenicidade , Ração Animal , Animais , Aderência Bacteriana , Equador , Flavobacteriaceae/isolamento & purificação , Flavobacteriaceae/patogenicidade , Lactococcus/isolamento & purificação , Lactococcus/fisiologia , Longevidade/fisiologia , Proteobactérias/classificação , Proteobactérias/isolamento & purificação , Proteobactérias/fisiologia , Alimentos Marinhos/microbiologia , Alimentos Marinhos/provisão & distribuição , Shewanella/isolamento & purificação , Shewanella/patogenicidade , Verrucomicrobia/classificação , Verrucomicrobia/isolamento & purificação , Verrucomicrobia/fisiologia , Vibrio/isolamento & purificação , Vibrio/patogenicidade
14.
Fish Shellfish Immunol ; 98: 1-9, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31904540

RESUMO

Tyramine (TA), a biogenic monoamine, plays various important physiological roles including immunological regulation in invertebrates. In this study, the effects of TA on the regulation of immune resistance, carbohydrate metabolism and biogenic monoamine, as well as its signaling pathway in Macrobrachium rosenbergii were determined. Results showed that total haemocyte count, hyaline cells, semigranular cells, and phenoloxidase activity per 50 µL of haemolymph and per granulocyte (the sum of semigranular and granular cells) at 0.5 h as well as phagocytic activity and clearance efficiency to Lactococcus garvieae at 1 h of prawn injected with TA at 1 nmol prawn-1 significantly increased, but the significantly decreased plasma lysozyme activity, phagocytic activity, clearance efficiency, and haemolymph glucose and dopamine were observed in prawn injected with TA at 10 nmol prawn-1 for 0.5 h. Respiratory bursts and haemolymph lactate in two TA-injection treatments at 0.5 h and 0.5-1 h, respectively, were significantly higher than those of the saline control, and in addition, TA depressed dopamine release in a dose-dependent manner after 0.5 h of TA injection. All the examined parameters returned to control levels after prawn injected with TA for 2 h. The inhibited effect of TA (at 10 nmol prawn-1 injection) on the phagocytic activity and clearance efficiency to pathogens was blocked by prazosin (an α1 adrenoceptors antagonist). For prawn received TA for 1 h then challenged with Lactococcus garvieae at 2 × 105 colony-forming units prawn-1, the survival ratio of TA 1 nmol prawn-1-injected prawn significantly increased by 20%, compared to the saline-challenged control or TA 10 nmol prawn-1-injected prawn after 144 h of challenge. These results suggested that the level of dopamine release suppression regulated by TA resulted in the immunoenhancing or immunosuppressive effects in prawn, and the signaling pathways of TA in mediating immune function were through octopamine (OA)/TA receptors.


Assuntos
Metabolismo dos Carboidratos/efeitos dos fármacos , Catecolaminas/metabolismo , Imunidade Inata/efeitos dos fármacos , Palaemonidae/efeitos dos fármacos , Tiramina/administração & dosagem , Animais , Lactococcus/fisiologia , Palaemonidae/imunologia
15.
Fish Shellfish Immunol ; 96: 279-289, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31783148

RESUMO

The interferon-induced GTP-binding protein Mx is responsible for a specific antiviral state against a broad spectrum of viral infections that are induced by type-I interferons (IFN α/ß) in different vertebrates. In this study, the Mx gene was isolated from the constructed mullet cDNA database. Structural features of mullet Mx (MuMx) were analyzed using different in-silico tools. The pairwise comparison revealed that the MuMx sequence was related to Stegastes partitus Mx with an 83.7% sequence identity, whereas MuMx was clustered into the teleost category in the phylogentic analysis. Sequence alignment showed that the dynamin-type guanine nucleotide-binding domain (G_DYNAMIN_2), central interactive domain (CID), and GTPase effector domain (GED) were conserved among Mx counterparts. The transcriptional expression of MuMx was the highest in blood cells from unchallenged fish. The temporal mRNA profile showed that MuMx expression was significantly elevated in all tissues, including blood, spleen, head kidney, liver, and gills after the injection of polyinosinic-polycytidylic acid (poly I:C) at many time points. Moreover, MuMx expression increased slightly, in the blood, spleen, and head kidney at a few time points after the injection of lipopolysaccharide (LPS) and Lactococcus garvieae (L. garvieae). Results of the subcellular localization analysis confirmed that the MuMx protein was highly expressed in the cytoplasm. The analysis of the gene expression of the viral hemorrhagic septicemia virus (VHSV) under conditions of MuMx overexpression confirmed the significant inhibition of viral transcripts. The cell viability (MTT) assay and VHSV titer quantification with the presence of MuMx indicated a significant reduction in virus replication. Collectively, these findings suggest that Mx is a specific immune-related gene that elicits crucial antiviral functions against viral antigens in the mullet fish.


Assuntos
Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Proteínas de Resistência a Myxovirus/genética , Proteínas de Resistência a Myxovirus/imunologia , Smegmamorpha/genética , Smegmamorpha/imunologia , Sequência de Aminoácidos , Animais , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Expressão Gênica , Perfilação da Expressão Gênica/veterinária , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Lactococcus/fisiologia , Lipopolissacarídeos/farmacologia , Proteínas de Resistência a Myxovirus/química , Novirhabdovirus/fisiologia , Filogenia , Poli I-C/farmacologia , Infecções por Rhabdoviridae/imunologia , Infecções por Rhabdoviridae/veterinária , Alinhamento de Sequência/veterinária
16.
Sci Rep ; 9(1): 14026, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31575902

RESUMO

Stress negatively impacts gut and brain health. Individual differences in response to stress have been linked to genetic and environmental factors and more recently, a role for the gut microbiota in the regulation of stress-related changes has been demonstrated. However, the mechanisms by which these factors influence each other are poorly understood, and there are currently no established robust biomarkers of stress susceptibility. To determine the metabolic and microbial signatures underpinning physiological stress responses, we compared stress-sensitive Wistar Kyoto (WKY) rats to the normo-anxious Sprague Dawley (SD) strain. Here we report that acute stress-induced strain-specific changes in brain lipid metabolites were a prominent feature in WKY rats. The relative abundance of Lactococcus correlated with the relative proportions of many brain lipids. In contrast, plasma lipids were significantly elevated in response to stress in SD rats, but not in WKY rats. Supporting these findings, we found that the greatest difference between the SD and WKY microbiomes were the predicted relative abundance of microbial genes involved in lipid and energy metabolism. Our results provide potential insights for developing novel biomarkers of stress vulnerability, some of which appear genotype specific.


Assuntos
Encéfalo/fisiologia , Microbioma Gastrointestinal/fisiologia , Estresse Fisiológico/fisiologia , Animais , Modelos Animais de Doenças , Lactococcus/fisiologia , Metabolismo dos Lipídeos/fisiologia , Lipídeos/sangue , Masculino , Metaboloma , Ratos , Ratos Endogâmicos WKY , Ratos Sprague-Dawley
17.
Fish Shellfish Immunol ; 93: 597-611, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31400511

RESUMO

The transcription factor, activator protein-1 (AP-1), is a dimeric protein and a downstream member of the mitogen-activated protein kinase (MAPK) signaling pathway. It regulates a wide array of functions including, cell proliferation, survival, differentiation, response to UV-irradiation, immune responses, and inflammatory conditions. AP-1 belongs to the basic leucine zipper (bZIP) protein family, which consists of members from Jun, Fos, Maf, and ATF subfamilies. In the present study, c-Jun and c-Fos homologs were identified from a transcriptome database of Liza haematocheila and designated as Lhc-Jun and Lhc-Fos. In both sequences, the signature bZIP domain was identified and also the DNA binding sites, dimerization sites, as well as the phosphorylation sites, were found to be highly conserved through evolution. Tissue distribution analysis revealed that both Lhc-Jun and Lhc-Fos transcripts were ubiquitously expressed in all examined tissues of healthy mullets. In order to determine the transcriptional modulations of Lhc-Jun and Lhc-Fos, challenge experiments were carried out using LPS, poly I:C, and L. garvieae. The qRT-PCR analysis revealed significant upregulation of Lhc-Jun and Lhc-Fos in blood, gill, liver, and spleen. This is the first study that explores the correlation between UV-irradiation and AP-1 ortholog expression in teleosts. Also, this is the first time that the functional characterization of the teleost c-Fos ortholog has been carried out. Sub-cellular localization of Lhc-Jun and Lhc-Fos was observed in the nucleus. AP-1-Luc reporter assays revealed significant higher luciferase activities in both Lhc-Jun and Lhc-Fos proteins compared to mock controls. These results strongly suggest that Lhc-Jun and Lhc-Fos might play a significant role in Liza haematocheila immunity by regulating AP-1 promoter sequences in immune and stress-related genes.


Assuntos
Doenças dos Peixes/imunologia , Peixes/genética , Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/imunologia , Sequência de Aminoácidos , Animais , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Lactococcus/fisiologia , Lipopolissacarídeos/farmacologia , Filogenia , Poli I-C/farmacologia , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/imunologia , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/imunologia , Alinhamento de Sequência/veterinária , Fator de Transcrição AP-1/química
18.
Curr Biol ; 29(10): R381-R393, 2019 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-31112692

RESUMO

Domestication refers to artificial selection and breeding of wild species to obtain cultivated variants that thrive in man-made niches and meet human or industrial requirements. Several genotypic and phenotypic signatures of domestication have been described in crops, livestock and pets. However, domestication is not unique to plants and animals. Microbial diversity has also been shaped by the emergence of novel and highly specific man-made environments, like food and beverage fermentations. This allowed rapid adaptation and diversification of various microbes, such as certain Lactococcus, Lactobacillus, Oenococcus, Saccharomyces and Aspergillus species. During the domestication process, microbes gained the capacity to efficiently consume particular nutrients, cope with a multitude of industry-specific stress factors and produce desirable compounds, often at the cost of a reduction in fitness in their original, natural environments. Moreover, different lineages of the same species adapted to highly diverse niches, resulting in genetically and phenotypically distinct strains. In this Review, we discuss the basic principles of microbial domestication and describe how recent research is uncovering its genetic underpinnings.


Assuntos
Lactobacillus/fisiologia , Lactococcus/fisiologia , Saccharomyces/fisiologia , Aspergillus/genética , Aspergillus/fisiologia , Domesticação , Variação Genética , Lactobacillus/genética , Lactococcus/genética , Oenococcus/genética , Oenococcus/fisiologia , Fenótipo , Saccharomyces/genética
19.
PLoS One ; 14(5): e0215375, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31050668

RESUMO

This study reports the characterization of the microbial community composition, and the establishment and dynamics of a continuous-flow competitive exclusion culture (CFCEC) derived from gut microbiomes of Nile tilapia (Oreochromis niloticus) specimens reared on aquaculture farms in Colombia. 16S rRNA gene amplicon Illumina sequencing was used to identify taxonomical changes in the CFCEC microbial community over time. The CFCEC was developed from adult tilapia from two farms in Colombia, and CFCEC samples were collected over two months. The pH varied from 6.25 to 6.35 throughout culturing, while anaerobic and aerobic cell counts stabilized at day 9, at 109 CFU mL-1 and were maintained to day 68. A variation in the CFCEC bacterial composition was observed over time. Cetobacterium was the most abundant in the first two days and coincided with a higher CFCEC supernatant antimicrobial effect against the fish pathogen Streptococcus agalactiae. Antimicrobial activity against S. agalactiae disappeared by day 3. Changes in bacterial composition continued to day 33 with Lactococcus spp. becoming the most abundant member of the community. In conclusion, the study of the CFCEC from intestinal tract of Nile tilapia (Oreochromis niloticus) by 16S rRNA gene sequencing allowed identification of predominant bacterial genera in the continuous-flow competitive exclusion culture exhibiting antibacterial activity against the fish pathogen Streptococcus agalactiae.


Assuntos
Bactérias/classificação , Ciclídeos/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , Streptococcus agalactiae/crescimento & desenvolvimento , Animais , Bactérias/isolamento & purificação , Carga Bacteriana , Técnicas Bacteriológicas , Colômbia , Fusobactérias/isolamento & purificação , Fusobactérias/fisiologia , Microbioma Gastrointestinal , Lactococcus/isolamento & purificação , Lactococcus/fisiologia , Viabilidade Microbiana , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
20.
Fish Shellfish Immunol ; 91: 264-274, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31128294

RESUMO

Brown trout are polymorphic salmonid species, and it is of importance to investigate whether hybridization affects disease resistance. In this study, susceptibility of brown trout (Salmo trutta Abant, Anatolian, Black Sea, and Caspius) strains and their hybrids to Lactococcus garvieae and Yersinia ruckeri as well as their immune-related gene expression profiles were studied. Results indicated that reciprocal hybridization did not affect disease resistance in brown trout strains. Purebred Black Sea strain of brown trout was the most resistant group against Y. ruckeri, followed by other Black Sea strain hybrids. On the other hand, purebred Anatolian strain was the most resistant group to L. garvieae, followed by other Anatolian strain hybrids. Expression pattern of target genes differed in families, but the overall gene expression was comparatively high in Y. ruckeri infected families. Upregulations were mainly significant at 7 and 28 d post infection while marginal regulations were observed 8 h after infection. Disease resistance status of strains was supported by high expression of immune-related genes such as major histocompatibility complex class I (MHC-I), immunoglobulin light chain (IgL), and antioxidant- and hemoglobin-related gene expression. Therefore, our findings suggest that Black Sea and Anatolian strains could be used to develop fish stock that are resistant for yersiniosis and lactocaccosis, respectively.


Assuntos
Suscetibilidade a Doenças/veterinária , Doenças dos Peixes/imunologia , Infecções por Bactérias Gram-Positivas/veterinária , Truta/genética , Truta/imunologia , Yersiniose/veterinária , Animais , Suscetibilidade a Doenças/imunologia , Infecções por Bactérias Gram-Positivas/imunologia , Hibridização Genética , Lactococcus/fisiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Transcriptoma , Yersiniose/imunologia , Yersinia ruckeri/fisiologia
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