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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.
J Pept Sci ; 24(7): e3089, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29808604

RESUMO

Cathelicidins are an important family of antimicrobial peptide effectors of innate immunity in vertebrates. Two members of this group, CATH-1 and CATH-2, have been identified and characterized in teleosts (ray-finned fish). In this study, we investigated the expression of these genes in different tissues of rainbow trout challenged with 4 different inactivated pathogens. By using qPCR, we detected a strong induction of both cath-1 and cath-2 genes within 24 hours after intraperitoneal inoculation with Lactococcus garvieae, Yersinia ruckeri, Aeromonas salmonicida, or Flavobacterium psychrophilum cells. Up to 700-fold induction of cath-2 was observed in the spleen of animals challenged with Y. ruckeri. Moreover, we found differences in the intensity and timing of gene up-regulation in the analyzed tissues. The overall results highlight the importance of cathelicidins in the immune response mechanisms of salmonids.


Assuntos
Aeromonas salmonicida/imunologia , Catelicidinas/imunologia , Flavobacterium/imunologia , Lactococcus/imunologia , Oncorhynchus mykiss/microbiologia , Yersinia ruckeri/imunologia , Aeromonas salmonicida/citologia , Animais , Antibacterianos/química , Antibacterianos/metabolismo , Catelicidinas/biossíntese , Catelicidinas/genética , Relação Dose-Resposta a Droga , Flavobacterium/citologia , Perfilação da Expressão Gênica , Lactococcus/citologia , Testes de Sensibilidade Microbiana , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/imunologia , Baço/imunologia , Baço/microbiologia , Relação Estrutura-Atividade , Yersinia ruckeri/citologia
3.
Food Funct ; 7(1): 104-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26437130

RESUMO

The dietary modulation of gut microbiota, suggested to be involved in allergy processes, has recently attracted much interest. While several studies have addressed the use of fibres to modify intestinal microbial populations, information about other components, such as phenolic compounds, is scarce. The aim of this work was to identify the dietary components able to influence the microbiota in 23 subjects suffering from rhinitis and allergic asthma, and 22 age- and sex-matched controls. The food intake was recorded by means of an annual food frequency questionnaire. Dietary fibre tables were obtained from Marlett et al., and the Phenol-Explorer database was used to assess the phenolic compound intake. The quantification of microbial groups was performed using an Ion Torrent 16S rRNA gene-based analysis. The results showed a direct association between the intake of red wine, a source of stilbenes, and the relative abundance of Bacteroides, and between the intake of coffee, rich in phenolic acids, and the abundance of Clostridium, Lactococcus and Lactobacillus genera. Despite epidemiological analyses not establishing causality, these results support the association between polyphenol-rich beverages and faecal microbiota in allergic patients.


Assuntos
Café/química , Microbioma Gastrointestinal/efeitos dos fármacos , Hipersensibilidade/imunologia , Hipersensibilidade/microbiologia , Fenóis/administração & dosagem , Vinho/análise , Adulto , Asma/microbiologia , Carga Bacteriana , Bacteroides/citologia , Bacteroides/efeitos dos fármacos , Clostridium/citologia , Clostridium/efeitos dos fármacos , Dieta , Fibras na Dieta/administração & dosagem , Fezes/microbiologia , Feminino , Flavonoides/administração & dosagem , Humanos , Hidroxibenzoatos/administração & dosagem , Lactobacillus/citologia , Lactobacillus/efeitos dos fármacos , Lactococcus/citologia , Lactococcus/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Rinite Alérgica/microbiologia , Estilbenos/administração & dosagem
4.
Mol Microbiol ; 79(3): 759-71, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21255117

RESUMO

Bacteria display a variety of shapes, which have biological relevance. In most eubacteria, cell shape is maintained by the tough peptidoglycan (PG) layer of the cell wall, the sacculus. The organization of PG synthesis machineries, orchestrated by different cytoskeletal elements, determines the specific shapes of sacculi. In rod-shaped bacteria, the actin-like (MreB) and the tubuline-like (FtsZ) cytoskeletons control synthesis of the sidewall (elongation) and the crosswall (septation) respectively. Much less is known concerning cell morphogenesis in cocci, which lack MreB proteins. While spherical cocci exclusively display septal growth, ovococci additionally display peripheral growth, which is responsible of the slight longitudinal expansion that generates their ovoid shape. Here, we report that the ovococcus Lactococcus lactis has the ability to become rod-shaped. L. lactis IL1403 wild-type cells form long aseptate filaments during both biofilm and planktonic growth in a synthetic medium. Nascent PG insertion and the division protein FtsK localize in multiple peripheral rings regularly spaced along the filaments. We show that filamentation results from septation inhibition, and that penicillin-binding proteins PBP2x and PBP2b play a direct role in this process. We propose a model for filament formation in L. lactis, and discuss the possible biological role of such morphological differentiation.


Assuntos
Parede Celular/metabolismo , Lactococcus/crescimento & desenvolvimento , Lactococcus/metabolismo , Morfogênese , Proteínas de Bactérias/metabolismo , Biofilmes/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Parede Celular/ultraestrutura , Lactococcus/citologia , Lactococcus/ultraestrutura , Meticilina/farmacologia , Modelos Biológicos , Morfogênese/efeitos dos fármacos , Coloração e Rotulagem , Frações Subcelulares/efeitos dos fármacos
5.
Plasmid ; 65(1): 8-14, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20832422

RESUMO

Using food and commensal lactic acid bacteria (LAB) as vehicles for DNA delivery into epithelial cells is a new strategy for vaccine delivery or gene therapy. However, present methods for DNA delivery with LAB have suffered low efficiency. Our goal was to develop a new system to deliver DNA into epithelial cells with high efficiency using food and commensal LAB. An Escherichia coli-LAB shuttle plasmid, pLKV1, for DNA delivery into eukaryotic cells was constructed. Two reporter plasmids with green and red fluorescent protein genes were also constructed to monitor the uptake of protein and DNA, respectively. Bacteria delivering these reporter plasmids into Caco-2 cells were monitored by fluorescence microscopy. Several methods that weaken the bacterial cell wall prior to co-culture with Caco-2 cells were evaluated for their role in the improvement of gene transfer efficiency. Treating Streptococcus gordonii with penicillin and lysozyme greatly increased its rate of gene delivery to mammalian cells compared to untreated control bacteria, while glycine pretreatment promoted the highest gene transfer rate for Lactococcus lactis. Uptake of green fluorescent bacteria by Caco-2 cells showed that the cell wall-weakening treatment promoted the internalization of the noninvasive bacteria into Caco-2 cells. In conclusion, we have developed a noninvasive system using LAB as a vehicle for vaccine delivery or gene therapy, and tested this system in vitro with Caco-2 cells.


Assuntos
Bactérias/metabolismo , Microbiologia de Alimentos , Ácido Láctico/metabolismo , Plasmídeos/genética , Transfecção/métodos , Bactérias/citologia , Células CACO-2 , Parede Celular/metabolismo , Escherichia coli/citologia , Escherichia coli/metabolismo , Genes Reporter/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Lactococcus/citologia , Lactococcus/metabolismo , Proteínas Luminescentes/metabolismo , Dados de Sequência Molecular , Streptococcus/citologia , Streptococcus/metabolismo
6.
Colloids Surf B Biointerfaces ; 52(2): 149-53, 2006 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16844359

RESUMO

Bacteria possess surface properties, related to their charge, hydrophobicity and Lewis acid/base characteristics, that are involved in the attachment processes of microorganisms to surfaces. Fermentation bulks and food matrixes are complex heterogeneous media containing various components with different physicochemical characteristics. The aim of the present study was to investigate whether (i) bacteria present in a food matrix, interacted physicochemically at their surface level with the other constituents and (ii) the diversity of bacterial surface properties could result in a diversity of microbial adhesion to components and thus in a diversity of tolerance to toxic compounds. The surface properties of 20 lactic acid bacteria were characterized by the MATS method showing their relatively hydrophilic and various basic characteristics. The results obtained from a set of representative strains showed that (i) the strains with higher affinity for apolar solvents adsorbed more to lipids and hydrophobic compounds, (ii) the more the strains adsorbed to a toxic solvent, the less they were tolerant to this solvent. A diversity of bacterial surface properties was observed for the strains in the same species showing the importance of choosing bacteria according to their surface properties in function of technological objectives.


Assuntos
Aderência Bacteriana/fisiologia , Microbiologia de Alimentos , Lactococcus/química , Lactococcus/fisiologia , Adsorção , Animais , Fenômenos Químicos , Físico-Química , Clorofórmio , Lactococcus/citologia , Lipídeos/química , Microscopia de Fluorescência , Leite/química , Leite/microbiologia , Odorantes , Propriedades de Superfície
7.
J Appl Microbiol ; 91(2): 312-21, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11473596

RESUMO

AIMS: To screen the cystathionine lyase and L-methionine aminotransferase activities of cheese-related bacteria (lactococci, non-starter lactobacilli and smear bacteria) and to determine the individual and interactive effects of temperature, pH and NaCl concentration on selected enzyme activities. METHODS AND RESULTS: A subcellular fractionation protocol and specific enzyme assays were used, and a quadratic response surface methodology was applied. The majority of the strains, 21 of 33, had detectable cystathionine lyase activity which differed in the specificity. Aminotransferase activity on L-methionine was observed in only three strains. The cystathionine lyase activities of Lactobacillus reuteri DSM20016, Lactococcus lactis subsp. cremoris MG1363, Brevibacterium linens 10 and Corynebacterium ammoniagenes 8 and the L-methionine aminotransferase activity of Lact. reuteri DSM20016 had temperature and pH optima of 30-45 degrees C, and 7.5-8.0, respectively. As shown by the quadratic response surface methodology these enzymes retained activities in the range of temperature, pH and NaCl concentration which characterized the cheeses from which the bacteria originated. CONCLUSION: The enzyme activities may have a role in flavour development during cheese ripening. SIGNIFICANCE AND IMPACT OF THE STUDY: The findings of this work contribute to the knowledge about the amino acid catabolic enzymes in order to improve cheese ripening.


Assuntos
Bactérias/enzimologia , Queijo/microbiologia , Liases/metabolismo , Cloreto de Sódio/farmacologia , Transaminases/metabolismo , Aminoácidos/metabolismo , Bactérias/citologia , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Corynebacterium/citologia , Corynebacterium/efeitos dos fármacos , Corynebacterium/enzimologia , Corynebacterium/metabolismo , Aromatizantes , Concentração de Íons de Hidrogênio , Lactobacillus/citologia , Lactobacillus/efeitos dos fármacos , Lactobacillus/enzimologia , Lactobacillus/metabolismo , Lactococcus/citologia , Lactococcus/efeitos dos fármacos , Lactococcus/enzimologia , Lactococcus/metabolismo , Concentração Osmolar , Temperatura
8.
Appl Environ Microbiol ; 66(5): 2216-9, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10788403

RESUMO

An immunofluorescent method involving double color labeling and confocal microscopy was reported to specifically detect lactic acid bacteria and probiotic cells coimmobilized in gels beads. The method described is rapid (4 h) and sensitive and may be useful for studying cell dynamics during mixed-culture starter production using immobilized cells in gel beads. Microscopic observations were perfectly correlated to cell counts obtained using a sandwich enzyme-linked immunosorbent assay.


Assuntos
Bifidobacterium/citologia , Células Imobilizadas , Lactococcus/citologia , Bifidobacterium/isolamento & purificação , Imunofluorescência , Corantes Fluorescentes , Géis , Lactococcus/isolamento & purificação , Lactococcus lactis/citologia , Lactococcus lactis/isolamento & purificação , Microscopia Confocal/métodos
9.
Appl Environ Microbiol ; 65(11): 4881-6, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10543799

RESUMO

The survival and the physiology of lactococcal cells in the different compartments of the digestive tracts of rats were studied in order to know better the fate of ingested lactic acid bacteria after oral administration. For this purpose, we used strains marked with reporter genes, the luxA-luxB gene of Vibrio harveyi and the gfp gene of Aequora victoria, that allowed us to differentiate the inoculated bacteria from food and the other intestinal bacteria. Luciferase was chosen to measure the metabolic activity of Lactococcus lactis in the digestive tract because it requires NADH, which is available only in metabolically active cells. The green fluorescent protein was used to assess the bacterial lysis independently of death. We report not only that specific factors affect the cell viability and integrity in some digestive tract compartments but also that the way bacteria are administrated has a dramatic impact. Lactococci which transit with the diet are quite resistant to gastric acidity (90 to 98% survival). In contrast, only 10 to 30% of bacteria survive in the duodenum. Viable cells are metabolically active in each compartment of the digestive tract, whereas most dead cells appear to be subject to rapid lysis. This property suggests that lactococci could be used as a vector to deliver specifically into the duodenum the proteins produced in the cytoplasm. This type of delivery vector would be particularly appropriate for targeting digestive enzymes such as lipase to treat pancreatic deficiencies.


Assuntos
Sistema Digestório/microbiologia , Conteúdo Gastrointestinal/microbiologia , Trânsito Gastrointestinal , Lactococcus/fisiologia , Animais , Feminino , Genes Reporter , Proteínas de Fluorescência Verde , Lactococcus/citologia , Luciferases/análise , Luciferases/genética , Proteínas Luminescentes/análise , Proteínas Luminescentes/genética , Plasmídeos , Ratos , Ratos Endogâmicos F344 , Cifozoários , Vibrio/genética
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