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1.
Appl Environ Microbiol ; 88(13): e0069022, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35695487

RESUMO

High-throughput sequencing and high-pressure liquid chromatography (HPLC) methods were used to investigate the influences of microbial dynamics on the quality and biogenic amine (BA) content during fish sauce fermentation. The homogeneity of total viable bacteria and lactic acid bacteria in fish sauce becomes higher as fermentation progresses. Tetragenococcus was the key genus of fish sauce fermentation. Carnobacterium (38.43%) and Lentibacillus (41.01%) were the dominant genera in the samples fermented for 3 months and 18 months, respectively. These three bacterial genera were significantly related to the physicochemical characteristics and characteristic flavors of the sauces. Tetragenococcus was significantly positively correlated with nitrogen oxides, the main characteristic flavor components in fish sauce. The BA content in fish sauce fermentation increased from 106.88 to 376.03 mg/kg, and the content of histamine reached 115.30 mg/kg at the end of fermentation, indicating that fish sauce has health risks. About 66.67% of Lentibacillus isolates were able to produce a large amount of BA, suggesting that Lentibacillus was the key genus for BA accumulation in fish sauce fermentation. Research on reducing the content of BA in fish sauce by intervening with regard to the fermentation temperature showed that a safe fish sauce product could be obtained at the fermentation temperature of about 25°C. These results help us to understand the contribution of microbial community composition to fish sauce fermentation and provide a basis for improving the quality and safety of fermented fish sauce. IMPORTANCE Traditional fermentation of fish sauce is mainly carried out by complex microbial communities from raw anchovies and processing environments. However, it is still unclear how the environmental microbiota influences the quality and the safety of fish sauce products. Therefore, this study comprehensively explained the influence of microorganisms on the quality and safety of fish sauce during the fermentation process in terms of physicochemical characters, flavors, and BA. Additionally, the accumulation of BA in fish sauce fermentation was controlled by intervening in the fermentation temperature. This finding contributes to a deeper understanding of the role of environmental microbiota during fermentation and provides data support for improving the safety of fish sauce.


Assuntos
Aminas Biogênicas , Microbiologia de Alimentos , Animais , Bactérias/genética , Enterococcaceae , Fermentação , Produtos Pesqueiros/análise , Peixes/microbiologia
2.
Food Microbiol ; 106: 104056, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35690450

RESUMO

This study aimed to investigate the formation and abatement strategies of biogenic amines (BAs) in the moromi contaminated accidently during Cantonese soy sauce (CSS) production processes. The ratio of total acid/amino nitrogen (TA/AAN) in koji can be used to predict the change in BAs content. Of the three main phases, BAs contents were more significantly increased once moromi manufacturing- and fermentation-phase were polluted. By co-culturing Tetragenococcus halophilus CGMCC3792 with Zygosaccharomyces rouxii CGMCC21865, BAs content was reduced by 59.96% and 51.10%, respectively, for the contaminated initial and fermenting moromi. Moreover, BAs content was reduced by 67.68% via the split batch fermentation method for the latter. Based on high throughput sequencing and metatranscriptome technology, BAs content was closely related to Lactobacillus abundance. It revealed the mechanism of abating BAs by inhibiting decarboxylase expression and changing redox potential. Therefore, it was an efficient strategy for abating BAs content and improving the flavor profile of CSS.


Assuntos
Alimentos de Soja , Zygosaccharomyces , Aminas Biogênicas/metabolismo , Enterococcaceae , Fermentação , Saccharomycetales , Zygosaccharomyces/genética
3.
Food Res Int ; 156: 111153, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35651019

RESUMO

Application of low-salt fish sauce is restricted by its easy spoilage and poor flavor formation. In this study, a salt-tolerant strain Tetragenococcus muriaticus with powerful salt tolerance was isolated as starter for the low-salt fish sauce fermentation. The 16S rRNA gene high-throughput sequencing showed that Staphylococcus was the main microbial genus at the beginning of fermentation, reaching 73.75%, followed by Tetragenococcus (16.36%) and Pseudomonas (6.68%), while Tetragenococcus quickly took over the dominant position with the relative abundance over 56.9% after 10 d fermentation and peaked at the end of fermentation. There were a total of 144 volatile compounds identified by HS-SPME-GC-MS, among which aldehydes, esters, alcohols, heterocycles, ketones, and acids were the main volatile flavor compounds and were mainly produced by Tetragenococcus, Synechococcus, Rhodococcus, Stenotrophomonas, Achromobacter, and Brucella based on the correlation network maps constructed by the Pearson's correlation coefficient after O2PLS evaluation. The Sobs, ACE, Chao, and Shannon indexes of microbial community were significantly reduced, while the Simpson index was markedly enhanced in the low-salt fish sauce fermented with T. muriaticus compared with them in the fish sauce without starter addition. The addition of T. muriaticus also obviously improved the types and concentrations of main volatile flavor compounds in the low-salt fish sauce. The correlation network map showed that Tetragenococcus was the only genus that played a crucial role in the spoilage microorganism inhibition and volatile flavor improvement in the fish sauce. T. muriaticus can be developed as a potential microbial starter for the industrial production of low-salt fish sauce.


Assuntos
Produtos Pesqueiros , Microbiota , Animais , Enterococcaceae/genética , Produtos Pesqueiros/análise , Peixes/genética , RNA Ribossômico 16S/genética
4.
Cells ; 11(12)2022 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-35741032

RESUMO

Ulcerative colitis (UC) is one of the major subtypes of inflammatory bowel disease with unknown etiology. Probiotics have recently been introduced as a treatment for UC. Tetragenococcus halophilus (T. halophilus) is a lactic acid-producing bacterium that survives in environments with high salt concentrations, though little is known about its immunomodulatory function as a probiotic. The purpose of this study is to determine whether T. halophilus exerts an anti-inflammatory effect on intestinal inflammation in mice. Colitis was induced in C57BL/6J mice by feeding 4% DSS in drinking water for 7 days. T. halophilus was orally administered with DSS. Anti-inflammatory functions were subsequently evaluated by flow cytometry, qRT-PCT, and ELISA. Gut microbial composition was analyzed by 16S rRNA metagenomic analysis. DSS-induced colitis mice treated with T. halophilus showed less weight loss and significantly suppressed colonic shortening compared to DSS-induced colitis mice. T. halophilus significantly reduced the frequency of the dendritic cell activation molecule CD83 in peripheral blood leukocytes and intestinal epithelial lymphocytes. Frequencies of CD8+NK1.1+ cells decreased in mice with colitis after T. halophilus treatment and IL-1ß levels were also reduced. Alteration of gut microbiota was observed in mice with colitis after administration of T. halophilus. These results suggest T. halophilus is effective in alleviating DSS-induced colitis in mice by altering immune regulation and gut microbiome compositions.


Assuntos
Colite Ulcerativa , Colite , Microbioma Gastrointestinal , Animais , Anti-Inflamatórios/farmacologia , Colite/tratamento farmacológico , Colite Ulcerativa/tratamento farmacológico , Células Dendríticas , Sulfato de Dextrana/farmacologia , Enterococcaceae , Inflamação , Camundongos , Camundongos Endogâmicos C57BL , RNA Ribossômico 16S/genética
5.
BMC Microbiol ; 22(1): 149, 2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35668352

RESUMO

BACKGROUND: Probiotic starters can improve the flavor profile, texture, and health-promoting properties of fermented foods. Tetragenococcus halophilus is a halophilic lactic acid bacterium that is a candidate starter for high-salt fermented foods. However, the species is known to produce biogenic amines, which are associated with neurotoxicity. Here, we report a probiotic starter strain of T. halophilus, EFEL7002, that is suitable for use in high-salt fermentation. RESULTS: EFEL7002 was isolated from Korean meju (fermented soybean) and identified as T. halophilus, with 99.85% similarity. The strain is safe for use in food as it is a non-hemolytic and non-biogenic amine producer. EFEL7002 is tolerant to gastrointestinal conditions and can adhere to Caco-2 cells. This strain showed antioxidant, anti-inflammatory, and protective effects against the human gut epithelial barrier. EFEL7002 grew well in media containing 0-18% NaCl showing maximum cell densities in 6% or 12% NaCl. CONCLUSIONS: T. halophilus EFEL7002 can be used as a health-promoting probiotic starter culture for various salty fermented foods.


Assuntos
Probióticos , Cloreto de Sódio , Aminas Biogênicas/análise , Células CACO-2 , Enterococcaceae , Fermentação , Microbiologia de Alimentos , Humanos , República da Coreia , Soja
6.
PLoS One ; 17(5): e0268142, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35533189

RESUMO

Trans-generational immune priming involves the transfer of immunological experience, acquired by the parents after exposure to pathogens, to protect their progeny against infections by these pathogens. Such natural mechanisms could be exploited to prevent disease expression in economically important insects, such as the honey bee. This mechanism occurs when honey bee queens are exposed to the pathogenic bacterium Paenibacillus larvae. Here, we tested whether natural or experimental exposure to Melissococcus plutonius-another bacterium triggering a disease in honey bee larvae-reduced the susceptibility of the queen's progeny to infection by this pathogen. Because the immunological response upon pathogen exposure can lead to fitness costs, we also determined whether experimental exposure of the queens affected them or their colony negatively. Neither natural nor experimental exposure induced protection in the honey bee larvae against the deleterious effects of M. plutonius. Our results provided no evidence for the occurrence of trans-generational immune priming upon exposure of the queen to M. plutonius. Whether this lack was due to confounding genetic resistance, to unsuitable exposure procedure or to the absence of trans-generational immune priming against this pathogen in honey bees remains to be determined.


Assuntos
Enterococcaceae , Paenibacillus larvae , Animais , Bactérias , Abelhas , Enterococcaceae/genética , Larva/microbiologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-35583422

RESUMO

The taxonomic positions of two novel strains isolated from larvae of an insect (Allomyrina dichotoma) collected in Jeju, Republic of Korea, were determined by a polyphasic approach. Strain BWB3-3T was closely related to the type strain of Vagococcus salmoninarum, having 97.2 % 16S rRNA gene sequence similarity, whereas strain BWM-S5T formed an independent cluster within the genus Enterococcus in the 16S rRNA gene phylogeny and the closest relative was the type strain of Enterococcus canis (98.1 % sequence similarity). The core gene analysis supported the phylogenetic positions of the isolates revealed by 16S rRNA gene phylogeny. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain BWB3-3T and the type strain of V. salmoninarum were 73.2 and 20.0 %, respectively, whereas strain BWM-S5 T showed an ANI value of 70.9 % with the type strain of Enterococcus canis. The dDDH values between strain BWM-S5T and all the type strains of Enterococcus species were ≤25.1 %. On the basis of the results obtained here, the two isolates are considered to constitute two novel species of the family Enterococcaceae, for which the names Vagococcus allomyrineae sp. nov. and Enterococcus larvae sp. nov. are proposed, with the type strains BWB3-3T (=KCTC 43277T=CCM 9080T) and BWM-S5T (=KACC 22156T=CCM 9075T), respectively.


Assuntos
Besouros , Ácidos Graxos , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Enterococcaceae , Enterococcus/genética , Ácidos Graxos/química , Larva , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
8.
Int J Food Microbiol ; 371: 109670, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35427955

RESUMO

High throughput sequencing has recently revealed the presence of Tetragenococcus-related DNA sequences in dairy environments such as brine and cheeses. In the present work, a selective medium was developed to isolate Tetragenococcus spp. from two ripened, traditional, Spanish, blue-veined cheese varieties made from raw milk. The strains recovered belonged to either Tetragenococcus koreensis or Tetragenococcus halophilus species. Twenty of these isolates (15 of T. koreensis and 5 of T. halophilus) were then subjected to a battery of phenotypic and genetic tests, and six strains (4 T. koreensis and 2 T. halophilus) to genome sequencing. Wide genetic and phenotypic diversity was noted. All strains grew poorly in milk, producing small quantities of lactic and acetic acids. Most strains used lactose as a carbon source and ferment milk citrate. In agreement, genome analysis detected in the genome of the six strains analyzed gene clusters harboring several lactose/galactose-related genes and genes encoding citrate metabolic enzymes (permease, citrate lyase, and oxaloacetate decarboxylase). Most of the tested strains were resistant to erythromycin and clindamycin, and a few to other antimicrobial agents, but neither known mutations nor acquired genes conferring resistance to antibiotics were identified in their genomes. Neither were genes coding for pathogenicity or virulence factors detected. Decarboxylase-encoding genes involved in biogenic amine production were not identified, in keeping with the strains' negative biogenic amine-producer phenotype. Genome comparison revealed vast arrays of genes (similar in number to those described in other lactic acid bacteria) coding for components of proteolytic and lipolytic systems. Tetragenococcus strains showing desirable traits plus the absence of detrimental features might be exploitable in the form of secondary, adjunct or ripening cultures to ensure the typical bouquet of traditional blue-veined cheeses is obtained, or to diversify the final flavor in other varieties.


Assuntos
Queijo , Animais , Aminas Biogênicas/metabolismo , Queijo/microbiologia , Citratos/metabolismo , Enterococcaceae , Genômica , Lactose/metabolismo , Leite/microbiologia , Fenótipo
9.
PLoS One ; 17(4): e0267473, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35472068

RESUMO

Japanese people have been consuming miso soup over generations; it is beneficial for health and longevity. In this study, Tetragenococcus halophilus No. 1 in miso was found to possess salient immunomodulatory functions. Recently, we also demonstrated its effect on boosting immunological robustness. Although the consumption of miso is suggested to affect health over generations, such a long-term experiment has not been conducted until now. Thus, we evaluated the effects of miso-derived T. halophilus No. 1 over generations on the immune system of mice. As the generations increase, the proportion of germinal center B cells tends to increase. Furthermore, we found that CD4+ T cells expressing CD69, an activation marker, were increased in the third generation of mice. In addition, the proportion of follicular helper T cells and regulatory T cells tended to increase. Among the subsets of CD4+ T cells in the fourth generation, effector T cells and effector memory T cells tended to increase. In contrast, central memory T cells and naive T cells decreased. Moreover, autoimmunity was suppressed by long-term administration of T. halophilus No. 1. Based on these findings, we believe that the long-term administration of T. halophilus No. 1 over generations promotes immune activation and tolerance and enhances immunological robustness.


Assuntos
Enterococcaceae , Alimentos de Soja , Animais , Linfócitos B , Humanos , Camundongos
10.
Food Res Int ; 155: 111083, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35400459

RESUMO

In this study, exopolysaccharides produced by Tetragenococcus halophilus were extracted and purified. Two fractions named EPS-1 and EPS-2 were obtained with average molecular weights of 2613.4 and 93.4 kDa, respectively. Analysis of the structures demonstrated that EPS-1 was mainly composed of galactose, glucose, mannose and glucuronic acid, and EPS-2 mostly consisted of glucose and mannose. 800 MHz nuclear magnetic resonance spectroscopy elucidated different and partial primary structures of EPS-1 and EPS-2. The microtopography was observed by atomic force microscope and scanning electron microscope. In addition, the two fractions exhibited antioxidant activities on DPPH, hydroxyl and ABTS•+ radicals. Furthermore, EPS-1 and EPS-2 could protect Lactococcus lactis against cryogenic and lyophilized stress. These results indicated that exopolysaccharides from T. halophilus in this study would have great potential in the application of food and pharmaceutical industry.


Assuntos
Manose , Polissacarídeos Bacterianos , Antioxidantes/química , Antioxidantes/farmacologia , Enterococcaceae , Glucose , Polissacarídeos Bacterianos/química
11.
Int J Biol Macromol ; 208: 288-298, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35248612

RESUMO

Tetragenococcus halophilus exopolysaccharides (THPS) are metabolites released by T. halophilus SNTH-8 to resist a high-salt environment. Although many studies have investigated the mechanisms underlying salt tolerance shown by T. halophilus, structural characteristics as well as antioxidant and emulsifying capacities of THPS remain unclear. In this study, we isolated and purified two components, THPS-1 and THPS-2, from T. halophilus SNTH-8. Purified THPS-1 and THPS-2 were composed of arabinose, xylose, fucose, galactose, glucose, and glucuronic acid at a molar ratio of 1.66:38.95:2.11:26.12:29.73:1.43 and 0.46:40.3:0.54:30.8:1.36:25.54, respectively. The average molecular weights of THPS-1 and THPS-2 were 14.98 kDa and 21.03 kDa, respectively. Moreover, the structures of THPS-1 and THPS-2 were investigated via fourier-transform infrared spectroscopy(FT-IR), nuclear magnetic resonance spectroscopy(NMR), scanning electron microscopy(SEM), and methylation analysis. THPS-1 was a highly branched polysaccharide with a backbone of α-D-(1,4)-Xyl, α-D-(1,6)-Glc and α-D-Xyl as the terminal, while THPS-2 was a highly branched polysaccharide with a backbone of α-D-(1,4)-Xyl and ß-D-GlcA as the terminal. The branches were identified as ß-D-(1,4,6)-Gal and ß-D-(1,6)-Gal. Both THPS-1 and THPS-2 exhibited high antioxidant and emulsifying capacities. Overall, our structural analysis of THPS may further enhance research on natural emulsifiers and antioxidants.


Assuntos
Antioxidantes , Polissacarídeos , Antioxidantes/química , Enterococcaceae , Polissacarídeos/química , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Microbiol Spectr ; 10(2): e0033622, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35311554

RESUMO

Tetragenococcus halophilus, a halophilic lactic acid bacterium, is used in the fermentation process of soy sauce manufacturing. For many years, bacteriophage infections of T. halophilus have been a major industrial problem that causes fermentation failure. However, studies focusing on the mechanisms of tetragenococcal host-phage interactions are not sufficient. In this study, we generated two phage-insensitive derivatives from the parental strain T. halophilus WJ7, which is susceptible to the virulent phage phiWJ7. Whole-genome sequencing of the derivatives revealed that insertion sequences were transposed into a gene encoding poly(ribitol phosphate) polymerase (TarL) in both derivatives. TarL is responsible for the biosynthesis of ribitol-containing wall teichoic acid, and WJ7 was confirmed to contain ribitol in extracted wall teichoic acid, but the derivative was not. Cell walls of WJ7 irreversibly adsorbed phiWJ7, but those of the phage-insensitive derivatives did not. Additionally, 25 phiWJ7-insensitive derivatives were obtained, and they showed mutations not only in tarL but also in tarI and tarJ, which are responsible for the synthesis of CDP-ribitol. These results indicate that phiWJ7 targets the ribitol-containing wall teichoic acid of host cells as a binding receptor. IMPORTANCE Information about the mechanisms of host-phage interactions is required for the development of efficient strategies against bacteriophage infections. Here, we identified the ribitol-containing wall teichoic acid as a host receptor indispensable for bacteriophage infection. The complete genome sequence of tetragenococcal phage phiWJ7 belonging to the family Rountreeviridae is also provided here. This study could become the foundation for a better understanding of host-phage interactions of tetragenococci.


Assuntos
Bacteriófagos , Ribitol , Bacteriófagos/genética , Parede Celular/metabolismo , Enterococcaceae/metabolismo , Ribitol/metabolismo
13.
J Fish Dis ; 45(5): 667-677, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35195301

RESUMO

In November 2018, Vagococcus salmoninarum was identified as the causative agent of a chronic coldwater streptococcosis epizootic in broodstock brook trout (Salvelinus fontinalis) at the Iron River National Fish Hatchery in Wisconsin, USA. By February 2019, the epizootic spread to adjacent raceways containing broodstock lake trout (Salvelinus namaycush), whereby fish were found to be coinfected with Carnobacterium maltaromaticum and V. salmoninarum. To differentiate these two pathogens and determine the primary cause of the lake trout morbidity, a quantitative real-time PCR (qPCR) was developed targeting the C. maltaromaticum phenylalanyl-tRNA synthase alpha subunit (pheS) gene. The qPCR was combined with a V. salmoninarum qPCR, creating a duplex qPCR assay that simultaneously quantitates C. maltaromaticum and V. salmoninarum concentrations in individual lake trout tissues, and screens presumptive isolates from hatchery inspections and wild fish from national fish hatchery source waters throughout the Great Lakes basin. Vagococcus salmoninarum and C. maltaromaticum were co-detected in broodstock brook trout from two tribal hatcheries and C. maltaromaticum was present in wild fish in source waters of several national fish hatcheries. This study provides a powerful new tool to differentiate and diagnose two emerging Gram-positive bacterial pathogens.


Assuntos
Doenças dos Peixes , Animais , Carnobacterium , Enterococcaceae/genética , Doenças dos Peixes/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária
14.
Sci Rep ; 12(1): 1415, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-35082330

RESUMO

Intestinal gluconeogenesis (IGN), gastric bypass (GBP) and gut microbiota positively regulate glucose homeostasis and diet-induced dysmetabolism. GBP modulates gut microbiota, whether IGN could shape it has not been investigated. We studied gut microbiota and microbiome in wild type and IGN-deficient mice, undergoing GBP or not, and fed on either a normal chow (NC) or a high-fat/high-sucrose (HFHS) diet. We also studied fecal and urine metabolome in NC-fed mice. IGN and GBP had a different effect on the gut microbiota of mice fed with NC and HFHS diet. IGN inactivation increased abundance of Deltaproteobacteria on NC and of Proteobacteria such as Helicobacter on HFHS diet. GBP increased abundance of Firmicutes and Proteobacteria on NC-fed WT mice and of Firmicutes, Bacteroidetes and Proteobacteria on HFHS-fed WT mice. The combined effect of IGN inactivation and GBP increased abundance of Actinobacteria on NC and the abundance of Enterococcaceae and Enterobacteriaceae on HFHS diet. A reduction was observed in the amounf of short-chain fatty acids in fecal (by GBP) and in both fecal and urine (by IGN inactivation) metabolome. IGN and GBP, separately or combined, shape gut microbiota and microbiome on NC- and HFHS-fed mice, and modify fecal and urine metabolome.


Assuntos
Derivação Gástrica/métodos , Microbioma Gastrointestinal/fisiologia , Gluconeogênese/fisiologia , Intestinos/metabolismo , Metaboloma , Estômago/metabolismo , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Animais , DNA Bacteriano/genética , Enterobacteriaceae/classificação , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Enterococcaceae/classificação , Enterococcaceae/genética , Enterococcaceae/isolamento & purificação , Ácidos Graxos Voláteis/metabolismo , Firmicutes/classificação , Firmicutes/genética , Firmicutes/isolamento & purificação , Intestinos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Filogenia , Proteobactérias/classificação , Proteobactérias/genética , Proteobactérias/isolamento & purificação , Estômago/microbiologia , Estômago/cirurgia
15.
J Vet Med Sci ; 84(3): 390-399, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35082220

RESUMO

Paenibacillus larvae and Melissococcus plutonius are the causative agents of American and European foulbroods of honey bees, respectively. Since their virulence and resistance to disinfectants differ depending on the genotypes/phenotypes of the strains, the discrimination of strain types is important for the effective control of these diseases. Methods to detect and differentiate pathogens in honey are useful for surveying the contamination status of beehives/apiaries. In the present study, we selected a sequence (GenBank accession no. FI763267) as the specific target for enterobacterial repetitive intergenic consensus (ERIC) II-type P. larvae strains for the first time and developed a novel multiplex PCR assay that precisely distinguishes between the major types of foulbrood pathogens (ERIC I and II P. larvae and typical and atypical M. plutonius) in one reaction. In addition, we found that commercially available kits designed for DNA extraction from Mycobacterium in feces efficiently extracted DNA from foulbrood pathogens in honey. Using the multiplex PCR assay and DNA extraction kits, all the targeted types of P. larvae and M. plutonius were detected in honey spiked with the pathogens at a concentration of 100 bacterial cells/strain/ml. Moreover, 94% of the Japanese honey samples examined in the present study were contaminated with one or more types of the foulbrood pathogens. These results indicate that the newly developed methods are useful for detecting foulbrood pathogens in honey. The epidemiological information obtained by these methods will contribute to the effective control of foulbroods in apiaries.


Assuntos
Paenibacillus larvae , Animais , Abelhas , Enterococcaceae/genética , Japão , Larva/microbiologia , Reação em Cadeia da Polimerase Multiplex/métodos , Reação em Cadeia da Polimerase Multiplex/veterinária , Paenibacillus larvae/genética , Estados Unidos
16.
J Antimicrob Chemother ; 77(4): 921-925, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35038329

RESUMO

OBJECTIVES: To investigate the genetic context and transferability of the oxazolidinone resistance genes cfr(D) and optrA in a porcine Vagococcus lutrae isolate. METHODS: V. lutrae isolate BN31 was screened for the presence of known oxazolidinone resistance genes via PCR assays. Conjugation experiments were carried out to assess horizontal transferability of resistance genes. WGS was performed using a combination of Nanopore MinION and Illumina HiSeq platforms. Detection of a translocatable unit (TU) was conducted by PCR. RESULTS: V. lutrae isolate BN31 harboured the oxazolidinone resistance genes cfr(D) and optrA. The optrA gene, together with the phenicol resistance gene fexA, was located on a novel pseudo-compound transposon, designated Tn7363. Tn7363 was bounded by two copies of the new insertion sequence ISVlu1, which represented a new member of the ISL3 family. A TU, comprising one copy of ISVlu1 and the segment between the two IS elements including the optrA gene, was detected. The cfr(D) gene and an erm(B) gene were identified on the broad-host-range Inc18 plasmid pBN31-cfrD, a pAMß1-like plasmid. Similar to plasmid pAMß1, plasmid pBN31-cfrD was conjugative. CONCLUSIONS: To the best of our knowledge, we report the first identification of the cfr(D) and optrA in Vagococcus. Two novel oxazolidinone resistance gene-carrying mobile genetic elements, Tn7363 and pBN31-cfrD, were identified in V. lutrae BN31. Considering their transmission potential, attention should be paid to the risk of transfer of the optrA and cfr(D) genes from V. lutrae to clinically more important bacterial pathogens.


Assuntos
Farmacorresistência Bacteriana , Enterococcus faecalis , Animais , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Enterococcaceae , Genes Bacterianos , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Suínos
17.
J Immunol Res ; 2021: 4973589, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722779

RESUMO

METHOD: This study included 74 Chinese male patients with HCC. They were divided into early (n = 19), intermediate (n = 37), and terminal (n = 18) groups, referred to as Barcelona Clinic Liver Cancer stage 0+A, B, and C+D, respectively. Paired fecal and plasma samples were collected. Microbial composition and profiles were analyzed by 16S rRNA gene sequencing. The levels of gut damage marker (regenerating islet-derived protein 3α (REG3α)) and microbial translocation markers (soluble CD14 (sCD14), lipopolysaccharide-binding protein (LBP), peptidoglycan recognition proteins (PGRPs)) were determined in plasma samples of patients by ELISA. Twenty plasma cytokine and chemokines were determined by Luminex. RESULTS: In early, intermediate, and terminal groups, the abundance of the Bifidobacteriaceae family decreased significantly (3.52%, 1.55%, and 0.56%, respectively, P = 0.003), while the abundance of the Enterococcaceae family increased significantly (1.6%, 2.9%, and 13.4%, respectively, P = 0.022). Levels of REG3α and sCD14 were markedly elevated only in the terminal group compared with the early (P = 0.025 and P = 0.048) and intermediate groups (P = 0.023 and P = 0.046). The level of LBP significantly increased in the intermediate (P = 0.035) and terminal (P = 0.025) groups compared with the early group. The PGRP levels were elevated only in the terminal group compared with the early group (P = 0.018). The ratio of Enterococcaceae to Bifidobacteriaceae was significantly associated with the levels of REG3α, LBP, sCD14, and PGRPs. With HCC progression, increased levels of inflammatory cytokines accompanied by a T cell-immunosuppressive response and microbial translocation were observed. CONCLUSION: Gut microbiota compositional and functional shift, together with elevated gut damage and microbial translocation, may promote HCC development by stimulating inflammatory response and suppressing T cell response.


Assuntos
Translocação Bacteriana/imunologia , Carcinoma Hepatocelular/imunologia , Disbiose/complicações , Microbioma Gastrointestinal/imunologia , Neoplasias Hepáticas/imunologia , Actinobacteria/genética , Actinobacteria/imunologia , Actinobacteria/isolamento & purificação , Idoso , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/microbiologia , Carcinoma Hepatocelular/patologia , DNA Bacteriano/isolamento & purificação , Progressão da Doença , Disbiose/diagnóstico , Disbiose/imunologia , Disbiose/microbiologia , Enterococcaceae/genética , Enterococcaceae/imunologia , Enterococcaceae/isolamento & purificação , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/microbiologia , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , RNA Ribossômico 16S
18.
J Insect Sci ; 21(6)2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34723329

RESUMO

One of the most serious bacterial pathogens of Western honey bees (Apis mellifera Linnaeus [Hymenoptera: Apidae]) is Melissococcus plutonius, the cause of the disease European foulbrood. Because European foulbrood is highly variable, with diverse outcomes at both the individual and colony levels, it is difficult to diagnose through visual inspection alone. Common lab diagnostic techniques include microscopic examination and molecular detection through PCR. In 2009, a lateral flow device was developed and validated for field diagnosis of European foulbrood. At the time, M. plutonius was thought to be genetically homogenous, but we have subsequently learned that this bacterium exists as multiple strains, including some strains that are classified as 'atypical' for which the lateral flow device is potentially less effective. These devices are increasingly used in the United States, though they have never been validated using strains from North America. It is essential to validate this device in multiple locations as different strains of M. plutonius circulate in different geographical regions. In this study, we validate the field use of the lateral flow device compared to microscopic examination and qPCR on larval samples from 78 commercial honey bee colonies in the United States with visual signs of infection. In this study, microscopic diagnosis was more sensitive than the lateral flow device (sensitivity = 97.40% and 89.47%, respectively), and we found no false positive results with the lateral flow device. We find high concurrence between the three diagnostic techniques, and all three methods are highly sensitive for diagnosing European foulbrood.


Assuntos
Infecções Bacterianas/veterinária , Abelhas/microbiologia , Enterococcaceae , Animais , Infecções Bacterianas/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real , Estados Unidos
19.
BMC Microbiol ; 21(1): 320, 2021 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-34798831

RESUMO

BACKGROUND: Tetragenococcus (T.) halophilus can be isolated from a variety of fermented foods, such as soy sauce, different soy pastes, salted fish sauce and from cheese brine or degraded sugar beet thick juice. This species contributes by the formation of short chain acids to the flavor of the product. Recently, T. halophilus has been identified as a dominant species in a seasoning sauce fermentation based on koji made with lupine seeds. RESULTS: In this study we characterized six strains of T. halophilus isolated from lupine moromi fermentations in terms of their adaptation towards this fermentation environment, salt tolerance and production of biogenic amines. Phylogenic and genomic analysis revealed three distinctive lineages within the species T. halophilus with no relation to their isolation source, besides the lineage of T. halophilus subsp. flandriensis. All isolated strains from lupine moromi belong to one lineage in that any of the type strains are absent. The strains form lupine moromi could not convincingly be assigned to one of the current subspecies. Taken together with strain specific differences in the carbohydrate metabolism (arabinose, mannitol, melibiose, gluconate, galactonate) and amino acid degradation pathways such as arginine deiminase pathway (ADI) and the agmatine deiminase pathway (AgDI) the biodiversity in the species of T. halophilus is greater than expected. Among the new strains, some strains have a favorable combination of traits wanted in a starter culture. CONCLUSIONS: Our study characterized T. halophilus strains that were isolated from lupine fermentation. The lupine moromi environment appears to select strains with specific traits as all of the strains are phylogenetically closely related, which potentially can be used as a starter culture for lupine moromi. We also found that the strains can be clearly distinguished phylogenetically and phenotypically from the type strains of both subspecies T. halophilus subsp. halophilus and T. halophilus subsp. flandriensis.


Assuntos
Enterococcaceae/isolamento & purificação , Enterococcaceae/metabolismo , Lupinus/microbiologia , Biodiversidade , Enterococcaceae/classificação , Enterococcaceae/genética , Fermentação , Aromatizantes/metabolismo , Lupinus/metabolismo , Filogenia , Sementes/metabolismo , Sementes/microbiologia
20.
J Invertebr Pathol ; 186: 107686, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34780719

RESUMO

Melissococcus plutonius is a pathogenic bacterium that affects honeybee brood triggering colony collapse in severe cases. The bacterium causes a European foulbrood (EFB) disease in the honeybee populations, impacting beekeeping and agricultural industries. The pathogenesis, epidemiology, and variants of M. plutonius have been studied, but the virulence factors involved in larval infection are still unknown. Recently, an in-silico study suggested putative genes that might play a role in the pathogenesis of EFB. However, studies are required to determine their function as virulence factors. In addition, the few studies of clonal complexes (CCs), virulence factors, and variation in the honeybee larvae mortality have interfered with the development of more efficient control methods. The research, development, and differences in virulence between genetic variants (CCs) of M. plutonius and potential virulence factors implicated in honeybee larval mortality are discussed in this review.


Assuntos
Abelhas/microbiologia , Enterococcaceae/fisiologia , Enterococcaceae/patogenicidade , Animais , Criação de Abelhas , Abelhas/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/microbiologia , Virulência , Fatores de Virulência/genética
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