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1.
J Dairy Sci ; 103(5): 4026-4042, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32173012

RESUMO

Understanding the microbial community of cheese is important in the dairy industry, as the microbiota contributes to the safety, quality, and physicochemical and sensory properties of cheese. In this study, the microbial compositions of different cheeses (Cheddar, provolone, and Swiss cheese) and cheese locations (core, rind, and mixed) collected from the Arbuthnot Dairy Center at Oregon State University were analyzed using 16S rRNA gene amplicon sequencing with the Illumina MiSeq platform (Illumina, San Diego, CA). A total of 225 operational taxonomic units were identified from the 4,675,187 sequencing reads generated. Streptococcus was observed to be the most abundant organism in provolone (72 to 85%) and Swiss (60 to 67%), whereas Lactococcus spp. were found to dominate Cheddar cheese (27 to 76%). Species richness varied significantly by cheese. According to alpha diversity analysis, porter-soaked Cheddar cheese exhibited the highest microbial richness, whereas smoked provolone cheese showed the lowest. Rind regions of each cheese changed color through smoking and soaking for the beverage process. In addition, the microbial diversity of the rind region was higher than the core region because smoking and soaking processes directly contacted the rind region of each cheese. The microbial communities of the samples clustered by cheese, indicated that, within a given type of cheese, microbial compositions were very similar. Moreover, 34 operational taxonomic units were identified as biomarkers for different types of cheese through the linear discriminant analysis effect size method. Last, both carbohydrate and AA metabolites comprised more than 40% of the total functional annotated genes from 9 varieties of cheese samples. This study provides insight into the microbial composition of different types of cheese, as well as various locations within a cheese, which is applicable to its safety and sensory quality.


Assuntos
Bactérias/isolamento & purificação , Queijo/microbiologia , Animais , Bactérias/classificação , Bovinos , Indústria de Laticínios , Lactococcus , Microbiota , Oregon , RNA Bacteriano , RNA Ribossômico 16S , Streptococcus/genética
2.
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
3.
J Food Prot ; 83(3): 542-551, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32084256

RESUMO

ABSTRACT: Mixed thermophilic and mesophilic commercial starter cultures (CSCs), particularly those including Streptococcus thermophilus as a primary milk acidifier, have been found to reduce growth and counteract in situ nisin A (NisA+) antilisterial effects by the novel, indigenous Lactococcus lactis subsp. cremoris M78 costarter in traditional Graviera thermized milk cheese curds. Therefore, this model challenge study evaluated growth and in situ NisA+ activity of strain M78 in coculture with S. thermophilus ST1 singly in sterilized raw milk (SRM). Strain ST1, derived from a CSC for cheese, was challenged at two inoculation levels (5 and 7 log CFU/mL) in SRM against 6 and 3 log CFU/mL of strain M78 and Listeria monocytogenes, respectively. Pure cultures of each strain and cocultures of strain ST1 with the CSC L. lactis LL2, in replacement of strain M78, served as controls. At the high (7-log) inoculation level, the rapid, competitive growth (>9.3 log CFU/mL) of S. thermophilus ST1 reduced growth of both L. lactis by at least 10-fold; the industrial strain LL2 retained slightly higher relative population densities (7.4 to 9.1%) than the wild NisA+ strain M78 (3.8 to 5.6%) after 6 h at 37°C, followed by an additional 66 h of incubation at 22°C. In full contrast, at the low (5-log) inoculation level, S. thermophilus ST1 failed to predominate in SRM at 6 h; thus, the starter lactic acid bacteria populations were reversed in favor of L. lactis. Notably, strain M78 retained higher relative population densities (83.0 to 90.1%) than the CSC strain LL2 (80.3 to 85.2%) at 22°C. Moreover, at the 5-log ST1 level, the direct and deferred in situ NisA+ activities of strain M78 were at similar levels with its pure culture with L. monocytogenes in SRM, whereas at the 7-log ST1 level, the respective NisA+ effects were counteracted. Hence, 10- to 100-fold lowered inoculation levels of CSC S. thermophilus are required to enhance the performance of the M78 costarter in traditional Greek cheese technologies.


Assuntos
Queijo/microbiologia , Lactococcus lactis , Lactococcus , Leite/microbiologia , Nisina , Animais , Grécia , Lactococcus/efeitos dos fármacos , Lactococcus/crescimento & desenvolvimento , Nisina/análise , Streptococcus thermophilus
4.
Int J Syst Evol Microbiol ; 70(1): 505-510, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31651376

RESUMO

A coccus strain designated S-13T was isolated from commercial baechu-kimchi in Korea. Comparison of the 16S rRNA gene sequence indicated that strain S-13T had the highest similarity to Lactococcus taiwanensis 0905C15T (97.9 %), Lactococcus lactis subsp. tructae L105T (97.6 %), Lactococcus lactis subsp. cremoris NCDO 607T (97.5 %), Lactococcus lactis subsp. hordniae NBRC 100931T (97.2 %), and Lactococcus lactis subsp. lactis JCM 5805T (97.2 %). The detailed phylogenetic analyses based on the 16S rRNA, rpoB and recA genes indicated that S-13T was separated from the other species and subspecies in the genus Lactococcus. The DNA-DNA relatedness between S-13T and closely related type strains, such as L. taiwanensis 0905C15T, L. lactis subsp. tructae L105T, L. lactis subsp. cremoris NCDO 607T, L. lactis subsp. hordniae NBRC 100931T, and L. lactis subsp. lactis JCM 5805T was 25.6, 20.4, 25.1, 20.2 and 21.7 %, respectively. The major fatty acids were C16 : 0, cyclo-C19 : 0ω8c and C 14 : 0. The DNA G+C content of S-13T was 39.4 mol%. From the results of the phenotypic characteristics and chemotaxonomic analysis, it was concluded that strain S-13T represents a novel species in the genus Lactococcus for which the name Lactococcus kimchii sp. nov. (=KCTC 21096T=NBRC 113348T) is proposed.


Assuntos
Alimentos e Bebidas Fermentados/microbiologia , Lactococcus/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Microbiologia de Alimentos , Genes Bacterianos , Ácido Láctico , Lactococcus/isolamento & purificação , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA
5.
Int J Food Microbiol ; 317: 108463, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-31809966

RESUMO

Paocai is a widely consumed Chinese traditional fermented vegetable product. To understand the effect of temperature on paocai fermentation flora, the bacterial community structure of paocai fermented at 10 °C, 15 °C, 25 °C and 35 °C was analyzed by culture-dependent and culture-independent methods. The results showed that increasing the fermentation temperature in a certain range is beneficial for rapid paocai acid production and shortening of the maturity period. Illumina Miseq sequencing was performed on 56 samples at different fermentation process temperatures using a culture-independent method. A total of 1,964,231 high-quality reads of 16S rRNA V3-V4 regions were obtained, and they were divided into 405 operational taxonomic units (OTUs) and identified as 213 bacterial genera. The bacterial diversity decreased with the progression of fermentation, and some spoiled samples had an increased diversity. The culture-independent method found that at 10 °C, Lactococcus appeared at the start of fermentation, Leuconostoc and Weissella appeared in the middle of fermentation, and Lactobacillus and Leuconostoc dominated fermentation in the late stage. At 15 °C, Lactococcus started fermentation, Leuconostoc appeared in the middle stage, and Lactobacillus was dominant in the late stage. At 25 °C, Lactococcus started fermentation, Weissella and Lactobacillus appeared in the middle stage, and Lactobacillus dominated fermentation in the late stage. Finally, at 35 °C, Lactococcus, Weissella, and Lactobacillus started fermentation, Weissella and Lactobacillus appeared in the middle stage, and Lactobacillus dominated fermentation in the late stage. A total of 647 strains of bacteria were isolated by culture-dependent methods and were divided into 12 genera and 19 species by randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) and 16S ribosomal RNA gene (rDNA) sequencing technology. More types of bacteria were isolated in the early stage of fermentation. At 10 °C, Lactococcus lactis began fermentation, and Lactobacillus brevis and Leuconostoc mesenteroides dominated acid production in the middle and late stages of paocai fermentation. At 15 °C, L. lactis initiates fermentation, while Lactobacillus plantarum dominates the acid fermentation of paocai. At 25 °C and 35 °C, there were a large number of Enterobacteriaceae bacteria in the start-up fermentation stage, and L. plantarum was dominant after 1-2 days of fermentation. Redundancy analysis (RDA) found that the lower the temperature, the more bacterial species that are produced, and the higher the temperature and the longer the time, the more obvious are the effects of L. plantarum on paocai. The results of dominant bacteria studied by culture-dependent and culture-independent methods are similar. The results indicate that most of the dominant microorganisms in the paocai fermentation system are culturable. This discovery can provide data and physical support for modernization and regulation of different types of paocai production.


Assuntos
Fermentação/fisiologia , Alimentos e Bebidas Fermentados/microbiologia , Lactobacillus plantarum/metabolismo , Lactococcus/metabolismo , Leuconostoc/metabolismo , Weissella/metabolismo , Temperatura Baixa , Técnicas de Cultura , DNA Bacteriano/genética , DNA Ribossômico/genética , Microbiologia de Alimentos/métodos , Temperatura Alta , Lactobacillus plantarum/genética , Lactococcus/genética , Leuconostoc/genética , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Weissella/genética
6.
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
7.
J Dairy Sci ; 103(1): 87-97, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677844

RESUMO

Previous research reported that fermented yak milk had a diverse microbial composition. For this study, raw yak milk, qula, and fermented yak milk samples were collected from the Aba Tibetan autonomous region of China. The genus and species microbial composition of these samples were analyzed by high-throughput sequencing of 16S rRNA and groEL gene amplicons, and the volatile profile of the samples was quantified by gas chromatography-mass spectrometry. The results indicated variation in abundance of microbiota at the genus level among the fermented yak milk samples, with Lactobacillus as the most abundant genus in the majority of samples, ranging from 41.6 to 98.3%. The volatile profile of the samples varied among those collected from different villages. Correlations between bacterial composition and volatile compounds of the samples were also observed. Lactobacillus displayed a significant correlation with volatile compounds such as benzaldehyde, 2,3-pentanedione, ethanol, and ethyl acetate, whereas the samples with relatively high abundance of Streptococcus and Lactococcus displayed relatively low contents of volatile compounds.


Assuntos
Bovinos , Produtos Fermentados do Leite/microbiologia , Lactobacillus/isolamento & purificação , Lactococcus/isolamento & purificação , Streptococcus/isolamento & purificação , Animais , Reatores Biológicos , China , Fermentação , Lactobacillus/genética , RNA Ribossômico 16S/genética
8.
J Dairy Sci ; 103(2): 1785-1794, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31864733

RESUMO

We investigated the distribution of pathogenic non-agalactiae gram-positive, catalase-negative cocci (GPCN) in a convenience sample of New York State dairy farms. Our primary objective with the clinical mastitis (CM) GPCN samples was to evaluate somatic cell count (SCC) resolution and bacteriological cure of Streptococcus dysgalactiae or Streptococcus uberis versus Lactococcus lactis or Lactococcus garvieae in cows that received an approved intramammary treatment. In phase I, we assessed the distribution of the GPCN and SCC resolution. In phase II, we evaluated the SCC resolution and bacteriological cure in CM samples from the 4 farms with the highest prevalence of L. lactis or L. garvieae in phase I. In phase I, 8,868 CM and subclinical mastitis (SCM) milk samples were received from 143 farms. The GPCN samples identified by culture were confirmed with MALDI-TOF. From the 473 MALDI-TOF-confirmed GPCN samples, 155 were S. dysgalactiae (33%); 150, S. uberis (32%); 112, L. lactis (24%); 16, L. garvieae (3%); and 40, other GPCN (8%). From these, 277 were CM samples and 127 were eligible for the evaluation of SCC resolution, which was defined as SCC ≤200,000 cells/mL in a composite sample 15 to 60 d post-diagnosis. The odds of SCC resolution in CM samples was evaluated with multivariable logistic regression, and the odds were 6.1 [95% confidence interval (CI):2.7-13.9] times higher for S. dysgalactiae or S. uberis compared with L. lactis or L. garvieae. In phase II, a total of 1,662 CM and SCM samples were evaluated with microbiological methods as in phase I, of which 211 samples were confirmed by MALDI-TOF: 39% were S. dysgalactiae (n = 61) and S. uberis (n = 21); 55%, L. lactis (n = 114) and L. garvieae (n = 2); and 6%, other GPCN (n = 13). In total, 168 CM samples were eligible for analysis and 118 were included in the final SCC resolution model. Similar statistical methods as in phase I were performed, and the odds of SCC resolution were 2.4 (95% CI: 1.1-5.5) times higher for S. dysgalactiae or S. uberis compared with L. lactis or L. garvieae. Bacteriological cure was defined as having a different or negative culture on a quarter sample taken 14 to 28 d after initial diagnosis. The odds of bacteriological cure (n = 121) were 8.0 (95% CI: 2.5-25.6) times higher for S. dysgalactiae or S. uberis compared with L. lactis or L. garvieae. Differences in SCC resolution and bacteriological cure between these groups may dictate a different management approach.


Assuntos
Fazendas , Lactococcus/isolamento & purificação , Mastite Bovina/microbiologia , Animais , Antibacterianos/uso terapêutico , Bovinos , Contagem de Células/veterinária , Indústria de Laticínios , Feminino , Humanos , Lactococcus lactis/isolamento & purificação , Mastite Bovina/epidemiologia , Mastite Bovina/patologia , Mastite Bovina/prevenção & controle , Leite/citologia , Leite/microbiologia , New York , Prevalência , Infecções Estreptocócicas/microbiologia , Streptococcus/isolamento & purificação
9.
Int J Syst Evol Microbiol ; 69(12): 3682-3688, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31644419

RESUMO

Strain 1JSPR-7T, a facultatively anaerobic bacterium isolated from the gut of larvae of Allomyrina dichotoma raised in Wanju-gun, Republic of Korea, was characterized using a polyphasic approach. Comparative analysis of 16S rRNA gene and rpoB gene sequences showed that strain 1JSPR-7T fell within the genus Lactococcus, forming a compact cluster with the type strain of four subspecies of Lactococcus lactis and Lactococcus taiwanensis. The 16S rRNA gene sequence of strain 1JSPR-7T revealed the highest homology with L. lactissubsp. lactis JCM 5805T (97.3 %) and L. lactissubsp. hordniae NBRC 100931T (97.1 %), and the rpoB gene sequence showed the highest similarity to L. lactissubsp. cremoris DSM 20069T (91.4 %) and L. lactissubsp. tructae L105T (91.4 %). The average nucleotide identity and digital DNA-DNA hybridization values indicated that strain 1JSPR-7T was a novel species of the genus Lacococcus. The major fatty acids (>10 % of the total fatty acids) were summed feature 7 (unknown 18.846, C19 : 1ω6c and/or C19 : 0cyclo ω10c), C16 : 0 and C14 : 0, and the predominant menaquinone was MK-8 with MK-7 as a minor one. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, an unidentified phospholipid and three unidentified glycolipids with diphosphatidylglycerol as the major one. The cell-wall peptidoglycan was of the A4α type with an interpeptide bridge comprising l-Lys-d-Asp. The DNA G+C content based on the whole genome sequences was 37.4 mol%. Based on the data obtained, strain 1JSPR-7T represents a novel species of the genus Lactococcus, for which the name Lactococcusallomyrinae sp. nov. is proposed. The type strain is 1JSPR-7T (=KACC 19319T=NBRC 113068T).


Assuntos
Besouros/microbiologia , Lactococcus/classificação , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Glicolipídeos/química , Lactococcus/isolamento & purificação , Larva/microbiologia , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
10.
J Dairy Sci ; 102(12): 10737-10747, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31521345

RESUMO

Alcoholic liver disease (ALD) is correlated with alcohol consumption, and ALD progression depends on various factors. Some lactic acid bacteria (LAB) are beneficial for mitigating ALD. However, the valuable effects of LAB-derived dairy products remain unclear. Here, we evaluated the effects of Lactococcus chungangensis CAU 1447 dry cells (CAU 1447) and cream cheese derived from CAU 1447 on ALD progression following long-term alcohol consumption in rats. Oral administration of CAU 1447 and CAU 1447 cream cheese significantly reduced alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, and triglyceride levels. We found that CAU 1447 and CAU 1447 cream cheese downregulated mRNA encoding various cytokines and antioxidative factors in the liver. Oral CAU 1447 cream cheese administration increased short-chain fatty acid, butyrate, and acetate levels in feces. Thus, administration of CAU 1447 and CAU 1447 cream cheese induced hepatoprotective effects, indicating potential applications as a supplement for ALD mitigation.


Assuntos
Lactococcus , Hepatopatias Alcoólicas/terapia , Probióticos/uso terapêutico , Animais , Fatores Biológicos/uso terapêutico , Queijo/microbiologia , Suplementos Nutricionais , Fezes/química , Fermentação , Masculino , Substâncias Protetoras/uso terapêutico , Ratos , Ratos Sprague-Dawley
11.
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
12.
J Dairy Sci ; 102(10): 8745-8755, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31400900

RESUMO

Mongolian traditionally fermented vrum is known for its functional characteristics, and indigenous microbial flora plays a critical role in its natural fermentation. However, studies of traditionally fermented vrum are still rare. In this study, we investigated the artisanal production of traditionally fermented vrum from Inner Mongolia. In general, its physicochemical composition was characterized by 34.5 ± 8% moisture, 44.9 ± 12.1% fat, 10.6 ± 3.2% protein, and 210 ± 102°T. The total lactic acid bacteria and yeast counts ranged from 50 to 2.8 × 108 cfu/g and from 0 to 1.1 × 106 cfu/g, respectively. We studied bacterial and fungal community structures in 9 fermented vrum; we identified 5 bacterial phyla represented by 11 genera (an average relative abundance >1%) and 8 species (>1%), and 3 fungal phyla represented by 8 genera (>1%) and 8 species (>1%). Relative abundance values showed that Lactococcus and Lactobacillus were the most common bacterial genera, and Dipodascus was the predominant fungal genus. This scientific investigation of the nutritional components, microbial counts, and community profiles in Mongolian traditionally fermented vrum could help to develop future functional biomaterials and probiotics.


Assuntos
Produtos Fermentados do Leite/microbiologia , Microbiota , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Reatores Biológicos , China , Fermentação , Fungos/classificação , Fungos/isolamento & purificação , Lactobacillales , Lactobacillus/classificação , Lactobacillus/isolamento & purificação , Lactococcus , Tipagem Molecular , Probióticos
13.
Mar Genomics ; 48: 100696, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31301990

RESUMO

To date, a number of bacteriophages that infect Lactococcus garvieae isolated from marine fish have been identified. However, the evolutionary insight between L. garvieae phages and other viral community have not yet been immersedly investigated. In this study, completed genomic sequence of phage PLgY-30 was obtained, a comparative analysis of three lytic phages, which have been using for phage typing and treatment of L. garvieae infecting marine fish, is conducted. The results revealed that the genomes of lytic phages specific for L. garvieae isolated from diseased marine fish share a high level of homology and almost all proteins are conserved. At genome level, no similarity was detected for either PLgY-30 or PLgY-16, while PLgW-1 shares only very limited homology (1%) with other sequences in Genbank database. In addition, the function of only 35% of ORFs in the PLgY-30 phage genomes could be predicted, demonstrating that it is novel phage. At protein level, lytic phage proteins shared a significant similarity to various proteins of global phage species isolated from dairy fermentation facilities that utilize L. lactis as a primary starter culture, called the 936 phage group. Genome organization and architecture of three lytic phages are also similar to that of the 936 phage group. To our knowledge, this is the first time lytic bacteriophages infecting L. garvieae from marine fish were characterized to genome level.


Assuntos
Bacteriófagos/classificação , Genoma Viral , Genômica , Lactococcus/virologia , Sequência de Aminoácidos , Evolução Biológica , Mutação INDEL , Lactococcus lactis/virologia , Fases de Leitura Aberta , Filogenia
14.
Cell Host Microbe ; 26(2): 265-272.e4, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31324413

RESUMO

Multiple research groups have shown that diet impacts the gut microbiome; however, variability in experimental design and quantitative assessment have made it challenging to assess the degree to which similar diets have reproducible effects across studies. Through an unbiased subject-level meta-analysis framework, we re-analyzed 27 dietary studies including 1,101 samples from rodents and humans. We demonstrate that a high-fat diet (HFD) reproducibly changes gut microbial community structure. Finer taxonomic analysis revealed that the most reproducible signals of a HFD are Lactococcus species, which we experimentally demonstrate to be common dietary contaminants. Additionally, a machine-learning approach defined a signature that predicts the dietary intake of mice and demonstrated that phylogenetic and gene-centric transformations of this model can be translated to humans. Together, these results demonstrate the utility of microbiome meta-analyses in identifying robust and reproducible features for mechanistic studies in preclinical models.


Assuntos
Dieta Hiperlipídica , Microbioma Gastrointestinal/fisiologia , Animais , Bactérias/classificação , Bactérias/genética , Bases de Dados Factuais , Dieta , Microbioma Gastrointestinal/genética , Humanos , Lactococcus/classificação , Lactococcus/genética , Aprendizado de Máquina , Camundongos , Filogenia
15.
Vet Immunol Immunopathol ; 213: 109885, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31307670

RESUMO

Protec™ is a commercial aquafeed (Skretting Italia) containing a combination of glucans, vitamin C, vitamin E and zinc (immune support pack). No research information concerning its capability to improve fish immune response is available, so in this study the potential immunomodulatory effects of Protec™ were investigated in rainbow trout (Oncorhynchus mykiss). Head kidney (HK) leukocytes from adult fish (100 g, n = 6) were in vitro incubated with Protec™ immune support pack resulting in significantly higher respiratory burst activity and proliferation. Specifically, sonicated Protec™ immune support pack (160 µg/ml) induced a respiratory burst response similar to that promoted by zymosan and lipopolysaccharide (LPS), while non-sonicated Protec™ immune support pack induced a response comparable to that of cells stimulated with phorbol myristate acetate (PMA). Moreover, the proliferation of leukocytes exposed to sonicated Protec™ immune support pack (20 µg/ml) was significantly higher than that of cells stimulated with zymosan, and it was comparable to the proliferation of cells stimulated with phytohaemagglutinin (PHA) and LPS. Afterwards, a feeding trial was performed in a rainbow trout farm. Two groups of juvenile rainbow trout (10 g) were acclimated for 7 weeks before the experiment and fed daily with a commercial control diet (Optiline HE, Skretting Italia) at 2% BW/day. At the end of acclimation, one group of fish was fed with Protec™ diet (Skretting Italia) at 2% BW/day whereas the other group continued to feed the control diet at the same level for further 4 weeks. Then, fish were sampled (HK leukocytes from n = 6 fish/group, serum from n = 12 fish/group) or intraperitoneally vaccinated against lactococcosis (n = 160/dietary group/time point). Fish fed the same diets for further 4 weeks after vaccination, then feeding returned to the control diet in both groups until the end of the trial. The specific antibody response was recorded at 4 and 8 weeks after vaccination (n = 12 fish/group). The administration of Protec™ significantly enhanced the respiratory burst activity of leukocytes and the synthesis of specific IgM against Lactococcus garvieae, whereas the serum lysozyme activity was unaffected. The present research suggests that the administration of Protec™ can improve both innate and adaptive immune response of rainbow trout, proving to be an interesting strategy for enhancing the immune reactivity of fish to vaccines.


Assuntos
Ração Animal , Anticorpos Antibacterianos/sangue , Infecções por Bactérias Gram-Positivas/veterinária , Imunidade Inata , Lactococcus , Oncorhynchus mykiss/imunologia , Imunidade Adaptativa , Adjuvantes Imunológicos/administração & dosagem , Animais , Proliferação de Células , Dieta/veterinária , Feminino , Doenças dos Peixes/imunologia , Infecções por Bactérias Gram-Positivas/imunologia , Imunoglobulina M/sangue , Leucócitos/imunologia , Oncorhynchus mykiss/microbiologia , Explosão Respiratória
16.
Lett Appl Microbiol ; 69(3): 204-211, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31250457

RESUMO

Despite of the beneficial relevance of several lactic acid bacteria (LAB) in the food industry, micro-organisms belonging to this group can determine spoilage in food products and carry a number of virulence and antibiotic resistance-related genes. This study aimed on the characterization of beneficial and safety aspects of five bacteriocinogenic LAB strains (Lactobacillus curvatus 12-named L. curvatus UFV-NPAC1), L. curvatus 36, Weissela viridescens 23, W. viridescens 31 and Lactococcus garvieae 36) isolated from an artisanal Brazilian calabresa, a traditional meat sausage. Regarding their beneficial aspects, all tested isolates were positive for mub, while EF226-cbp, EF1249-fbp and EF2380-maz were detected in at least one tested strain; none of the isolates presented map, EFTu or prgB. However, evaluated strains presented a variable pattern of virulence-related genes, but none of the strains presented gelE, cylA, efsA, cpd, int-Tn or sprE. Moreover, other virulence-related genes evaluated in this study were detected at different frequencies. L. curvatus 12 was generated positive results for ace, ccf, int, ermC, tetL, aac(6')-Ie-aph(2″)-Ia, aph(2″)-Ib, aph(2″)-Ic, bcrB, vanB and vanC2; L. curvatus 36: hyl, asa1, esp, int, ermC, tetK, aph(3')-IIIa, aph(2'')-Ic and vanC2; L. garvieae 32: asa1, ant(4')-Ia, aph(2'')-Ib, catA, vanA and vanC1; W. viridescens 23: esp, cob, ermB, aph(3')-IIIa, aph(2'')-Ic, vanA, vanB and vanC2; W. viridescens 31: hyl, esp, ermC, aph(3')-IIIa, aph(2'')-Ib, aph(2'')-Ic, catA, vanA and vanB. Despite presenting some beneficial aspects, the presence of virulence and antibiotic resistance genes jeopardize their utilization as starter or biopreservatives cultures in food products. Considering the inhibitory potential of these strains, an alternative would be the use of their bacteriocins as semi-purified or pure technological preparation. SIGNIFICANCE AND IMPACT OF THE STUDY: The food industry has a particular interest in using bacteriocinogenic lactic acid bacteria (LAB) as starter, probiotics and/or biopreservatives in different food products. Characterization of additional beneficial features is important to identify new, multifunctional potential probiotic strains. However, these strains can only be applied in food products only after being properly characterized according their potential negative aspects, such as virulence and antibiotic resistance genes. A wide characterization of beneficial and safety aspects of bacteriocinogenic LAB is determinant to guide the proper utilization of these strains, or their purified bacteriocins, by the food industry.


Assuntos
Antibacterianos/farmacologia , Bacteriocinas/biossíntese , Lactobacillales/genética , Fatores de Virulência/genética , Brasil , Resistência Microbiana a Medicamentos/genética , Enterococcus/isolamento & purificação , Microbiologia de Alimentos , Lactobacillales/isolamento & purificação , Lactobacillus/efeitos dos fármacos , Lactococcus/isolamento & purificação , Produtos da Carne/microbiologia , Virulência
17.
World J Microbiol Biotechnol ; 35(7): 102, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31236715

RESUMO

Preparation of curd vary worldwide due to which its taste, texture and impact on human health also differ. In Assam, curd prepared from raw milk (RMC) is preferred over curd prepared from boiled milk (BMC), a tradition believed to have originated from the Mongoloid customs. Microbial diversity of raw milk (RM), boiled milk (BM), RMC and BMC collected from three farms were investigated by culture dependent and independent techniques. Additionally, metabolite profiles of RMC and BMC were studied by gas chromatography and mass spectroscopy. A total of 59 bacterial isolates were identified from the four different dairy products. In RM, lactic acid bacteria such as Lactococcus, Enterococcus, Lactobacillus and Leuconostoc were obtained along with the environmental bacteria like Bacillus, Staphylococcus, Acetobacter, Chryseobacterium, Streptococcus, Acinetobacter, Kocuria, Klebsiella and Macrococcus. Additionally, Prevotella, Oscillospira, Phascolarctobacterium and Akkermansia were also detected in BM by culture independent technique. In RMC and BMC, Lactococcus, Leuconostoc and Lactobacillus were prevalent. RM and RMC shared Enterococcus, Lactococcus, Streptococcus and Acinetobacter as common bacterial genera. However, no bacterial genus was common in BM and BMC. The correlation analysis revealed that Lactobacillus was negatively correlated to other bacterial genera. Oligotyping analysis revealed that Lactobacillus brevis and L.fermentum were abundant in RMC and BMC, respectively. In metabolomic study, ascorbic acid, dodecanoic acid and hexadecanoic acid were found to be significantly higher in RMC. Presence of different types of probiotics in these curds samples opens a new avenue to understand their effects on human health.


Assuntos
Bactérias/isolamento & purificação , Biodiversidade , Fermentação , Leite/microbiologia , Animais , Bactérias/metabolismo , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Enterococcus/isolamento & purificação , Enterococcus/metabolismo , Manipulação de Alimentos , Microbiologia de Alimentos , Sequenciamento de Nucleotídeos em Larga Escala , Lactobacillales , Lactobacillus/isolamento & purificação , Lactobacillus/metabolismo , Lactococcus/isolamento & purificação , Lactococcus/metabolismo , Leuconostoc/isolamento & purificação , Leuconostoc/metabolismo , Metagenômica , Análise Multivariada , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/isolamento & purificação
18.
Vet Res ; 50(1): 32, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31046823

RESUMO

Lactococcus garvieae is a significant pathogen in aquaculture with a potential zoonotic risk. To begin to characterize the late immune response of trout to lactococcosis, we selected infected individuals showing clinical signs of lactococcosis. At the time lactococcosis clinical signs appeared, infection by L. garvieae induced a robust inflammatory response in the spleen of rainbow trout, which correlated with abundant granulomatous lesions. The response in kidney goes in parallel with that of spleen, and most of the gene regulations are similar in both organs. A correlation existed between the early inflammatory granulomas in spleen (containing macrophages with internalized L. garvieae) and up-regulated gene sets, which defined the presence of macrophages and neutrophils. This is the first analysis of the immune transcriptome of rainbow trout following L. garvieae infection during the initiation of adaptive immune mechanisms and shows a transcriptome induction of antibody response by both IgM (+) and IgT (+) spleen B cells to respond to systemic infection. These results increase our understanding of lactococcosis and pave the way for future research to improve control measures of lactococcosis on fish farms.


Assuntos
Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Positivas/veterinária , Granuloma/veterinária , Rim/metabolismo , Lactococcus , Baço/metabolismo , Esplenopatias/veterinária , Truta/microbiologia , Animais , Doenças dos Peixes/metabolismo , Doenças dos Peixes/patologia , Infecções por Bactérias Gram-Positivas/metabolismo , Infecções por Bactérias Gram-Positivas/microbiologia , Granuloma/metabolismo , Granuloma/microbiologia , Granuloma/patologia , Rim/patologia , Análise de Sequência com Séries de Oligonucleotídeos/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Baço/patologia , Esplenopatias/metabolismo , Esplenopatias/microbiologia , Esplenopatias/patologia , Transcriptoma , Truta/metabolismo
19.
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
20.
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
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