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1.
J Basic Microbiol ; : e202300773, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38712352

RESUMO

Wastewater-based epidemiology provides temporal and spatial information about the health status of a population. The objective of this study was to analyze and report the epidemiological dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the province of Tucumán, Argentina during the second and third waves of coronavirus disease 2019 (COVID-19) between April 2021 and March 2022. The study aimed to quantify SARS-CoV-2 RNA in wastewater, correlating it with clinically reported COVID-19 cases. Wastewater samples (n = 72) were collected from 16 sampling points located in three cities of Tucumán (San Miguel de Tucumán, Yerba Buena y Banda del Río Salí). Detection of viral nucleocapsid markers (N1 gene) was carried out using one-step reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Viral loads were determined for each positive sample using a standard curve. A positive correlation (p < 0.05) was observed between viral load (copies/mL) and the clinically confirmed COVID-19 cases reported at specific sampling points in San Miguel de Tucumán (SP4, SP7, and SP8) in both months, May and June. Indeed, the high viral load concurred with the peaks of COVID-19 cases. This method allowed us to follow the behavior of SARS-CoV-2 infection during epidemic outbreaks. Thus, wastewater monitoring is a valuable epidemiological indicator that enables the anticipation of increases in COVID-19 cases and tracking the progress of the pandemic. SARS-CoV-2 genome-based surveillance should be implemented as a routine practice to prepare for any future surge in infections.

2.
Front Microbiol ; 15: 1343541, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476941

RESUMO

Inorganic phosphate (Pi) concentration modulates polyphosphate (polyP) levels in diverse bacteria, affecting their physiology and survival. Lactiplantibacillus paraplantarum CRL 1905 is a lactic acid bacterium isolated from quinoa sourdough with biotechnological potential as starter, for initiating fermentation processes in food, and as antimicrobial-producing organism. The aim of this work was to evaluate the influence of the environmental Pi concentration on different physiological and molecular aspects of the CRL 1905 strain. Cells grown in a chemically defined medium containing high Pi (CDM + P) maintained elevated polyP levels up to late stationary phase and showed an enhanced bacterial survival and tolerance to oxidative stress. In Pi sufficiency condition (CDM-P), cells were ~ 25% longer than those grown in CDM + P, presented membrane vesicles and a ~ 3-fold higher capacity to form biofilm. Proteomic analysis indicated that proteins involved in the "carbohydrate transport and metabolism" and "energy production and conversion" categories were up-regulated in high Pi stationary phase cells, implying an active metabolism in this condition. On the other hand, stress-related chaperones and enzymes involved in cell surface modification were up-regulated in the CDM-P medium. Our results provide new insights to understand the CRL 1905 adaptations in response to differential Pi conditions. The adjustment of environmental Pi concentration constitutes a simple strategy to improve the cellular fitness of L. paraplantarum CRL 1905, which would benefit its potential as a microbial cell factory.

3.
Appl Microbiol Biotechnol ; 97(17): 7831-44, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23832109

RESUMO

Ability of industrially relevant species of thermophilic lactobacilli strains to hydrolyze proteins from animal (caseins and ß-lactoglobulin) and vegetable (soybean and wheat) sources, as well as influence of peptide content of growth medium on cell envelope-associated proteinase (CEP) activity, was evaluated. Lactobacillus delbrueckii subsp. lactis (CRL 581 and 654), L. delbrueckii subsp. bulgaricus (CRL 454 and 656), Lactobacillus acidophilus (CRL 636 and 1063), and Lactobacillus helveticus (CRL 1062 and 1177) were grown in a chemically defined medium supplemented or not with 1 % Casitone. All strains hydrolyzed mainly ß-casein, while degradation of αs-caseins was strain dependent. Contrariwise, κ-Casein was poorly degraded by the studied lactobacilli. ß-Lactoglobulin was mainly hydrolyzed by CRL 656, CRL 636, and CRL 1062 strains. The L. delbrueckii subsp. lactis strains, L. delbrueckii subsp. bulgaricus CRL 656, and L. helveticus CRL 1177 degraded gliadins in high extent, while the L. acidophilus and L. helveticus strains highly hydrolyzed soy proteins. Proteinase production was inhibited by Casitone, the most affected being the L. delbrueckii subsp. lactis species. This study highlights the importance of proteolytic diversity of lactobacilli for rational strain selection when formulating hydrolyzed dairy or vegetable food products.


Assuntos
Proteínas de Bactérias/química , Caseínas/química , Lactobacillus/enzimologia , Lactoglobulinas/química , Peptídeo Hidrolases/química , Proteínas de Plantas/química , Verduras/química , Animais , Biocatálise , Bovinos , Laticínios/análise , Hidrólise , Lactobacillus/química , Lactobacillus/classificação , Glycine max/química , Triticum/química
4.
ACS Omega ; 8(50): 48042-48049, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38144080

RESUMO

In the past 50 years, life expectancy has increased by more than 20 years. One consequence of this increase in longevity is the rise of age-related diseases such as dementia. Alzheimer's disease (AD) is the most common form of dementia, accounting for 60-70% of cases. AD pathogenesis is not restricted to the neuronal compartment but includes strong interactions with other brain cells, particularly microglia triggering the release of inflammatory mediators, which contribute to disease progression and severity. There is growing evidence revealing the diverse clinical benefits of postbiotics in many prevalent conditions, including neurodegenerative diseases. Here, we tested the ability of bacterial conditioned media (BCM) derived from selected lactic acid bacteria (LAB) strains to regulate core mechanisms relevant to AD pathophysiology in the microglia cell line BV-2. Levilactobacillus brevis CRL 2013, chosen for its efficient production of the neurotransmitter GABA, and Lactobacillus delbrueckii subsp. lactis CRL 581, known for its anti-inflammatory properties, were selected alongside Enterococcus mundtii CRL 35, a LAB strain that can significantly modulate cytokine production. BCM from all 3 strains displayed antioxidant capabilities, reducing oxidative stress triggered by beta-amyloid oligomers (oAß1-42). Additionally, BCM effectively mitigated the expression of inflammatory cytokines, namely, TNF-α, IL-1ß, and IL-6 triggered by oAß1-42. Furthermore, our study identified that BCM from CRL 581 inhibit the activity of acetylcholinesterase (AChE), a crucial enzyme in AD progression, in both human erythrocytes and mouse brain tissues. Notably, the inhibitory effect was mediated by low-molecular-weight components of the BCM. L. delbrueckii subsp. lactis CRL 581 emerged as a favorable candidate for production of postbiotics with potential benefits for AD therapy since it demonstrated potent antioxidant activity, reduction of cytokine expression, and partial AChE inhibition. On the other hand, E. mundtii CRL 35 showed that the antioxidant activity failed to inhibit AChE and caused induction of iNOS expression, rendering it unsuitable as a potential therapeutic for AD. This study unveils the potential benefits of LAB-derived postbiotics for the development of new avenues for therapeutic interventions for AD.

5.
J Bacteriol ; 194(2): 538-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22207745

RESUMO

Lactobacillus curvatus is one of the most prevalent lactic acid bacteria found in fermented meat products. Here, we present the draft genome sequence of Lactobacillus curvatus CRL705, a bacteriocin producer strain isolated from an Argentinean artisanal fermented sausage, which consists of 1,833,251 bp (GC content, 41.9%) and two circular plasmids of 12,342 bp (pRC12; GC, 43.9%) and 18,664 bp (pRC18; GC, 34.4%).


Assuntos
Genoma Bacteriano , Lactobacillus/classificação , Lactobacillus/genética , Fermentação , Microbiologia de Alimentos , Produtos da Carne/microbiologia , Dados de Sequência Molecular
6.
Foodborne Pathog Dis ; 9(1): 68-74, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22011041

RESUMO

Listeria monocytogenes is a foodborne pathogen causative of opportunistic infections. Listeriosis is associated with severe infections in pregnant women causing abortion or neonatal listeriosis. An alternative to antibiotics are safe novel bacteriocins peptides such as enterocin CRL35 with strong antilisterial activity produced by Enterococcus mundtii CRL35. In the present paper, our goal is to study the effectiveness of this peptide and the producer strain in a murine model of pregnancy-associated listeriosis. A single dose of 5×10(9) colony-forming unit of L. monocytogenes FBUNT (Faculty of Biochemistry-University of Tucumán) resulted in translocation of pathogen to liver and spleen of BALB/c pregnant mice. The maximum level of Listeria was observed on day 3 postinfection. Interestingly, the intragastric administration of enterocin CRL35 significantly reduced the translocation of the pathogen to vital organs. On the other hand, the preadministration of E. mundtii CRL35 slightly inhibited this translocation. Listeria infection caused a significant increase in polymorphonuclear leukocytes at day 3 postinfection compared to the noninfected group. This value was reduced after the administration of enterocin CRL35. No significant changes were observed in either white blood cells or lymphocytes counts. Based on the data presented in the present work enterocin CRL35 would be a promising alternative for the prevention of Listeria infections.


Assuntos
Antibacterianos/farmacologia , Bacteriocinas/farmacologia , Enterococcus/química , Listeria monocytogenes/efeitos dos fármacos , Listeriose/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Administração Oral , Animais , Antibacterianos/isolamento & purificação , Antibacterianos/uso terapêutico , Bacteriocinas/isolamento & purificação , Bacteriocinas/uso terapêutico , Feminino , Humanos , Leucócitos , Leucocitose/sangue , Listeria monocytogenes/crescimento & desenvolvimento , Listeriose/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos/isolamento & purificação , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Gravidez , Complicações Infecciosas na Gravidez/microbiologia
7.
Food Res Int ; 155: 111097, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35400469

RESUMO

The synthesis of nanoparticles (NPs) by microorganisms is one of the most promising areas of research in modern nanotechnology since microorganisms can easily act as real nanofactories of industrially relevant compounds. Recent studies suggest that probiotic bacteria have an intrinsic potential to synthesize metal NPs when grown in the presence of metal ions. In such conditions, they can reduce metal ions through different biochemical mechanisms occurring both intra and extracellularly, and leading to the production of NPs. Different approaches have proposed the synthesis of silver, gold, titanium or selenium NPs from probiotics, with promising health related effects. However, their use for the production of iron and zinc NPs has been scarcely reported. Considering the nutritional relevance of iron and zinc, a thorough approach about the synthesis of iron and zinc NPs by probiotics was addressed, including the factors affecting the synthesis processes, the mechanisms of synthesis, and the physical and chemical characterization of NPs. The impact of products containing probiotics and minerals has applications in many different fields going beyond the food industry and representing a powerful strategy as economic engine for very diverse industries and countries.


Assuntos
Nanopartículas Metálicas , Probióticos , Íons , Ferro , Nanopartículas Metálicas/química , Zinco
8.
Front Immunol ; 12: 647049, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912172

RESUMO

Myelosuppression is the major dose-limiting toxicity of cancer chemotherapy. There have been many attempts to find new strategies that reduce myelosuppression. The dietary supplementation with lactic acid bacteria (LAB) improved respiratory innate immune response and the resistance against respiratory pathogens in immunosupressed hosts. Although LAB viability is an important factor in achieving optimal protective effects, non-viable LAB are capable of stimulating immunity. In this work, we studied the ability of oral preventive administration of viable and non-viable Lactobacillus rhamnosus CRL1505 or L. plantarum CRL1506 (Lr05, Lr05NV, Lp06V or Lp06NV, respectively) to minimize myelosuppressive and immunosuppressive effects derived from chemotherapy. Cyclophosphamide (Cy) impaired steady-state myelopoiesis in lactobacilli-treated and untreated control mice. Lr05V, Lr05NV and Lp06V treatments were the most effective to induce the early recovery of bone marrow (BM) tissue architecture, leukocytes, myeloid, pool mitotic and post-mitotic, peroxidase positive, and Gr-1Low/High cells in BM. We selected the CRL1505 strain for being the one capable of maintaining its myelopoiesis-enhancing properties in its non-viable form. Although the CRL1505 treatments do not modify the Cy ability to induce apoptosis, both increased the incorporation of BrdU in BM cells. Consequently, Lr05NV and Lr05V treatments were able to promote early recovery of LSK cells (Lin-Sca-1+c-Kit+ cells), multipotent progenitors (Lin-Sca-1+c-Kit+CD34+ cells), and myeloid cells (Gr-1+Ly6G+Ly6C- cells) with respect to the untreated Cy control. In addition, these treatments were able to increase the frequency of IL17A-producing innate lymphoid cells in the intestinal lamina propria (IL-17A+RORγt+CD4-NKp46+ cells) after Cy injection. These results were correlated with an increase in the IL-17A serum levels, a GM-CSF high expression and a CXCL12 lower expression in BM. Therefore, both Lr05V and Lr05NV treatments are able to activate beneficially the IL-17A/GM-CSF axis and accelerate the recovery of Cy-induced immunosuppression by increasing BM myeloid precursors. We demonstrated for the first time the beneficial effect of CRL1505 strain on myelopoiesis affected by a chemotherapeutic drug. Furthermore, Lr05NV could be a good and safe resource for reducing chemotherapy-induced leukopenia. The results are a starting point for future research and open up broad prospects for future applications of the immunobiotics.


Assuntos
Ciclofosfamida/toxicidade , Hospedeiro Imunocomprometido/efeitos dos fármacos , Lacticaseibacillus rhamnosus/imunologia , Lactobacillus/imunologia , Mielopoese/efeitos dos fármacos , Probióticos/administração & dosagem , Administração Oral , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/imunologia , Hospedeiro Imunocomprometido/imunologia , Imunossupressores/toxicidade , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Contagem de Leucócitos , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Linfócitos/metabolismo , Masculino , Camundongos , Células Mieloides/efeitos dos fármacos , Células Mieloides/imunologia , Mielopoese/imunologia
9.
BMC Genom Data ; 22(1): 29, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479493

RESUMO

BACKGROUND: 6S RNA is a regulator of cellular transcription that tunes the metabolism of cells. This small non-coding RNA is found in nearly all bacteria and among the most abundant transcripts. Lactic acid bacteria (LAB) constitute a group of microorganisms with strong biotechnological relevance, often exploited as starter cultures for industrial products through fermentation. Some strains are used as probiotics while others represent potential pathogens. Occasional reports of 6S RNA within this group already indicate striking metabolic implications. A conceivable idea is that LAB with 6S RNA defects may metabolize nutrients faster, as inferred from studies of Echerichia coli. This may accelerate fermentation processes with the potential to reduce production costs. Similarly, elevated levels of secondary metabolites might be produced. Evidence for this possibility comes from preliminary findings regarding the production of surfactin in Bacillus subtilis, which has functions similar to those of bacteriocins. The prerequisite for its potential biotechnological utility is a general characterization of 6S RNA in LAB. RESULTS: We provide a genomic annotation of 6S RNA throughout the Lactobacillales order. It laid the foundation for a bioinformatic characterization of common 6S RNA features. This covers secondary structures, synteny, phylogeny, and product RNA start sites. The canonical 6S RNA structure is formed by a central bulge flanked by helical arms and a template site for product RNA synthesis. 6S RNA exhibits strong syntenic conservation. It is usually flanked by the replication-associated recombination protein A and the universal stress protein A. A catabolite responsive element was identified in over a third of all 6S RNA genes. It is known to modulate gene expression based on the available carbon sources. The presence of antisense transcripts could not be verified as a general trait of LAB 6S RNAs. CONCLUSIONS: Despite a large number of species and the heterogeneity of LAB, the stress regulator 6S RNA is well-conserved both from a structural as well as a syntenic perspective. This is the first approach to describe 6S RNAs and short 6S RNA-derived transcripts beyond a single species, spanning a large taxonomic group covering multiple families. It yields universal insights into this regulator and complements the findings derived from other bacterial model organisms.


Assuntos
Regulação Bacteriana da Expressão Gênica , Lactobacillales/genética , RNA Bacteriano/genética , RNA não Traduzido/genética , Bacillus subtilis/genética , Sequência Conservada/genética , Humanos , Sintenia/genética
10.
Biochimie ; 168: 185-189, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31715214

RESUMO

Lactobacillus coryniformis CRL 1001 and L. reuteri CRL 1098 have the complete genes necessary to synthesize pseudo-cobalamin as final product in a vitamin B12 free commercial medium. Unlike vitaminB12 (the most biologically active form), the pseudo-cobalamin contains adenine instead of 5,6-dimethlbenzimidazole (DMB) in the Coα-ligand. Considering the vitamin B12-gene clusters of these bacteria, the aim of this work was to analyze the production of corrinoids with DMB (vitamin B12) instead of adenine (pseudo-B12) as lower ligand base in a vitamin B12 free chemically defined medium (CDM) without purines. Genome-wide screening of genes related to purine metabolism showed that both strains possess all pur genes necessary for the synthesis of inositol monophosphate, the main precursor for purine biosynthesis. Accordingly, both strains were able to grow in B12 free CDM without purines, with the supplementation of different synthetic intermediaries. Isolated compounds with positive vitamin B12 activity were quantified and characterized by LC/MS-MS. Total corrinoids values were higher for both strains in comparison to those obtained in vitaminB12 free commercial medium. Interestingly, CRL 1001 strain synthesized cobalamin, suggesting that this strain is able to activate DMB as nitrogenous base instead adenine when it is in excess in a purine-free medium. The present paper represents the first demonstration of a partial metabolic shift to produce vitamin B12 in a Lactobacillus strain.


Assuntos
Lactobacillus/metabolismo , Limosilactobacillus reuteri/metabolismo , Purinas/metabolismo , Vitamina B 12/análogos & derivados , Vitamina B 12/metabolismo , Meios de Cultura/metabolismo , Redes e Vias Metabólicas
11.
Microbiol Resour Announc ; 8(15)2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30975815

RESUMO

Lactobacillus plantarum CRL681 was isolated from Argentinean artisanal fermented sausages. Here, the draft genome sequence of the CRL681 strain is described. The reads were assembled into contigs with a total estimated size of 3,370,224 bp. A total of 3,300 open reading frames (ORFs) were predicted, including 3,126 protein-coding sequences. The draft genome sequence of L. plantarum CRL681 will be useful for understanding the organism's metabolic activities and for biotechnological applications.

12.
Biochim Biophys Acta Gen Subj ; 1863(8): 1283-1291, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31059750

RESUMO

BACKGROUND: The scope of the present work was to characterize the activity of class IIa bacteriocins in Listeria (L.) monocytogenes cells that constitutively express an activated form of PrfA, the virulence master regulator, since bacteriocin sensitivity was only characterized in saprophytic cells so far. The mannose phosphotransferase system (Man-PTS) has been shown to be the class IIa bacteriocin receptor in Listeria; hence, special attention was paid to its expression in virulent bacteria. METHODS: L. monocytogenes FBprfA* cells were obtained by transconjugation. Bacterial growth was studied in TSB and glucose containing-minimal medium. Sensitivity to antimicrobial peptides was assessed by killing curves. Membranes of L. monocytogenes FBprfA* cells were characterized using proteomic and lipidomic approaches. RESULTS: The mannose phosphotransferase system (Man-PTS) was downregulated upon expression of PrfA*, and these cells turned out to be more sensitive to enterocin CRL35 and pediocin PA-1, while not to nisin. Proteomic and lipidomic analysis showed differences between wild type (WT) and PrfA* strains. For instance, phosphatidic acid was only detected in PrfA* cells, whereas, there was a significant decline of plasmalogen-phosphatidylglycerol in the same strain. CONCLUSIONS: Our results support a model in which Man-PTS acts just as a docking molecule that brings class IIa bacteriocins to the plasma membrane. Furthermore, our results suggest that lipids play a crucial role in the mechanism of action of bacteriocins. GENERAL SIGNIFICANCE: This is the first demonstration of the link between L. monocytogenes virulence and the bacterial sensitivity toward pediocin-like peptides.


Assuntos
Proteínas de Bactérias/metabolismo , Bacteriocinas/metabolismo , Listeria monocytogenes/metabolismo , Fatores de Terminação de Peptídeos/metabolismo , Receptores de Superfície Celular/metabolismo , Meios de Cultura , Glucose/metabolismo , Listeria monocytogenes/crescimento & desenvolvimento
13.
Infect Immun ; 76(6): 2696-705, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18390997

RESUMO

Nisin-controlled gene expression was used to develop a recombinant strain of Lactococcus lactis that is able to express the pneumococcal protective protein A (PppA) on its surface. Immunodetection assays confirmed that after the induction with nisin, the PppA antigen was predictably and efficiently displayed on the cell surface of the recombinant strain, which was termed L. lactis PppA. The production of mucosal and systemically specific antibodies in adult and young mice was evaluated after mice were nasally immunized with L. lactis PppA. Immunoglobulin M (IgM), IgG, and IgA anti-PppA antibodies were detected in the serum and bronchoalveolar lavage fluid of adult and young mice, which showed that PppA expressed in L. lactis was able to induce a strong mucosal and systemic immune response. Challenge survival experiments demonstrated that immunization with L. lactis PppA was able to increase resistance to systemic and respiratory infection with different pneumococcal serotypes, and passive immunization assays of naïve young mice demonstrated a direct correlation between anti-PppA antibodies and protection. The results presented in this study demonstrate three major characteristics of the effectiveness of nasal immunization with PppA expressed as a protein anchored to the cell wall of L. lactis: it elicited cross-protective immunity against different pneumococcal serotypes, it afforded protection against both systemic and respiratory challenges, and it induced protective immunity in mice of different ages.


Assuntos
Proteínas de Bactérias/imunologia , Lactococcus lactis/genética , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Administração Intranasal , Envelhecimento , Animais , Anticorpos Antibacterianos/biossíntese , Afinidade de Anticorpos , Proteínas de Bactérias/administração & dosagem , Proteínas de Bactérias/biossíntese , Clonagem Molecular , Regulação Bacteriana da Expressão Gênica , Imunoglobulina G/biossíntese , Lactococcus lactis/metabolismo , Camundongos , Vacinas Pneumocócicas/administração & dosagem
14.
Appl Environ Microbiol ; 74(12): 3682-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18424544

RESUMO

The cell envelope-associated proteinases (CEPs) of the lactobacilli have key roles in bacterial nutrition and contribute to the development of the organoleptic properties of fermented milk products as well, as they can release bioactive health-beneficial peptides from milk proteins. The influence of the peptide supply, carbohydrate source, and osmolites on the CEP activity of the cheese starter Lactobacillus delbrueckii subsp. lactis CRL 581 was investigated. The CEP activity levels were controlled by the peptide content of the growth medium. The maximum activity was observed in a basal minimal defined medium, whereas in the presence of Casitone, Casamino Acids, or yeast extract, the synthesis of CEP was inhibited 99-, 70-, and 68-fold, respectively. The addition of specific di- or tripeptides containing branched-chain amino acids, such as leucylleucine, prolylleucine, leucylglycylglycine, or leucylproline, to the growth medium negatively affected CEP activity, whereas dipeptides without branched-chain amino acids had no effect on the enzyme's production. The carbon source and osmolites did not affect CEP activity. The CEP of L. delbrueckii subsp. lactis CRL 581 exhibited a mixed-type CEP(I/III) variant caseinolytic specificity. Mass-spectrometric screening of the main peptide peaks isolated by reverse-phase high-pressure liquid chromatography allowed the identification of 33 and 32 peptides in the alpha(s1)- and beta-casein hydrolysates, respectively. By characterizing the peptide sequence in these hydrolysates, a pattern of alpha(s1)- and beta-casein breakdown was defined and is reported herein, this being the first report for a CEP of L. delbrueckii subsp. lactis. In this pattern, a series of potentially bioactive peptides (antihypertensive and phosphopeptides) which are encrypted within the precursor protein could be visualized.


Assuntos
Caseínas/metabolismo , Lactobacillus delbrueckii/enzimologia , Peptídeo Hidrolases/metabolismo , Peptídeos/metabolismo , Sequência de Aminoácidos , Carboidratos , Carbono/metabolismo , Cromatografia Líquida de Alta Pressão , Meios de Cultura/química , Regulação Bacteriana da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Cinética , Lactobacillus delbrueckii/crescimento & desenvolvimento , Lipídeos , Espectrometria de Massas , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/isolamento & purificação , Proteínas de Vegetais Comestíveis/metabolismo , Análise de Sequência de Proteína , Especificidade por Substrato
15.
Food Microbiol ; 25(3): 442-51, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18355669

RESUMO

Whey, a by-product of the cheese industry usually disposed as waste, is a source of biological and functional valuable proteins. The aim of this work was to evaluate the potentiality of three lactic acid bacteria strains to design a starter culture for developing functional whey-based drinks. Fermentations were performed at 37 and 42 degrees C for 24h in reconstituted whey powder (RW). Carbohydrates, organic acids and amino acids concentrations during fermentation were evaluated by RP-HPLC. Proteolytic activity was measured by the o-phthaldialdehyde test and hydrolysis of whey proteins was analyzed by Tricine SDS-PAGE. The studied strains grew well (2-3log cfu/ml) independently of the temperature used. Streptococcus thermophilus CRL 804 consumed 12% of the initial lactose concentration and produced the highest amount of lactic acid (45 mmol/l) at 24h. Lactobacillus delbrueckii subsp. bulgaricus CRL 454 was the most proteolytic (91 microg Leu/ml) strain and released the branched chain amino acids Leu and Val. In contrast, Lactobacillus acidophilus CRL 636 and S. thermophilus CRL 804 consumed most of the amino acids present in whey. The studied strains were able to degrade the major whey proteins, alpha-lactalbumin being degraded in a greater extent (2.2-3.4-fold) than beta-lactoglobulin. Two starter cultures were evaluated for their metabolic and proteolytic activities in RW. Both cultures acidified and reduced the lactose content in whey in a greater extent than the strains alone. The amino acid release was higher (86 microg/ml) for the starter SLb (strains CRL 804+CRL 454) than for SLa (strains CRL 804+CRL 636, 37 microg/ml). Regarding alpha-lactalbumin and beta-lactoglobulin degradation, no differences were observed as compared to the values obtained with the single cultures. The starter culture SLb showed high potential to be used for developing fermented whey-based beverages.


Assuntos
Indústria Alimentícia , Microbiologia de Alimentos , Lactobacillus acidophilus/metabolismo , Lactobacillus delbrueckii/metabolismo , Proteínas do Leite/metabolismo , Streptococcus thermophilus/metabolismo , Aminoácidos/metabolismo , Metabolismo dos Carboidratos , Queijo , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Fermentação , Hidrólise , Lactobacillus acidophilus/crescimento & desenvolvimento , Lactobacillus delbrueckii/crescimento & desenvolvimento , Streptococcus thermophilus/crescimento & desenvolvimento , Proteínas do Soro do Leite
16.
Artigo em Inglês | MEDLINE | ID: mdl-30533893

RESUMO

This report describes the draft genome sequences of Lactobacillus salivarius A3iob and Lactobacillus johnsonii CRL1647, probiotic strains isolated from the gut of honeybee Apis mellifera workers. The reads were generated by a whole-genome sequencing (WGS) strategy on an Illumina MiSeq sequencer and were assembled into contigs with total sizes of 2,054,490 and 2,137,413 bp for the A3iob and CRL1647 strains, respectively. The draft genome sequences of L. salivarius A3iob and L. johnsonii CRL1647 will be useful for further studies of the specific genetic features of these strains and for understanding the mechanisms of their probiotic properties.

17.
Artigo em Inglês | MEDLINE | ID: mdl-30533786

RESUMO

This report describes the draft genome sequence of Lactobacillus brevis TUCO-5E, a probiotic strain isolated from porcine maternal milk. The reads were generated by a whole-genome sequencing (WGS) strategy on an Illumina MiSeq sequencer and were assembled into contigs with a total estimated size of 2,461,089 bp. A total of 2,455 open reading frames (ORFs) were predicted, including 2,301 protein-coding sequences. The draft genome sequence of L. brevis TUCO-5E will be useful for further studies of specific genetic features and for understanding the mechanisms of its probiotic properties in the porcine host.

18.
Front Immunol ; 9: 2178, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30319634

RESUMO

In lactic acid bacteria, the synthesis of exopolysaccharides (EPS) has been associated with some favorable technological properties as well as health-promoting benefits. Research works have shown the potential of EPS produced by lactobacilli to differentially modulate immune responses. However, most studies were performed in immune cells and few works have concentrated in the immunomodulatory activities of EPS in non-immune cells such as intestinal epithelial cells. In addition, the cellular and molecular mechanisms involved in the immunoregulatory effects of EPS have not been studied in detail. In this work, we have performed a genomic characterization of Lactobacillus delbrueckii subsp. delbrueckii TUA4408L and evaluated the immunomodulatory and antiviral properties of its acidic (APS) and neutral (NPS) EPS in porcine intestinal epithelial (PIE) cells. Whole genome sequencing allowed the analysis of the general features of L. delbrueckii TUA4408L genome as well as the characterization of its EPS genes. A typical EPS gene cluster was found in the TUA4408L genome consisting in five highly conserved genes epsA-E, and a variable region, which includes the genes for the polymerase wzy, the flippase wzx, and seven glycosyltransferases. In addition, we demonstrated here for the first time that L. delbrueckii TUA4408L and its EPS are able to improve the resistance of PIE cells against rotavirus infection by reducing viral replication and regulating inflammatory response. Moreover, studies in PIE cells demonstrated that the TUA4408L strain and its EPS differentially modulate the antiviral innate immune response triggered by the activation of Toll-like receptor 3 (TLR3). L. delbrueckii TUA4408L and its EPS are capable of increasing the activation of interferon regulatory factor (IRF)-3 and nuclear factor κB (NF-κB) signaling pathways leading to an improved expression of the antiviral factors interferon (IFN)-ß, Myxovirus resistance gene A (MxA) and RNaseL.


Assuntos
Antivirais/imunologia , Células Epiteliais , Mucosa Intestinal , Lactobacillus delbrueckii , Polissacarídeos Bacterianos , Rotavirus/imunologia , Animais , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Células Epiteliais/virologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/virologia , Lactobacillus delbrueckii/genética , Lactobacillus delbrueckii/imunologia , Polissacarídeos Bacterianos/genética , Polissacarídeos Bacterianos/imunologia , Suínos
19.
Genome Announc ; 5(9)2017 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-28254966

RESUMO

The genome of the immunomodulatory strain Lactobacillus jensenii TL2937 is described here. The draft genome has a total length of 1,678,416 bp, a G+C content of 34.3%, and 1,470 predicted protein-coding sequences. The genome information will be useful for gaining insight into the immunomodulatory properties of the TL2937 strain in the porcine host.

20.
Genome Announc ; 5(50)2017 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-29242218

RESUMO

The genome sequence of the immunomodulatory strain Lactobacillus rhamnosus strain IBL027 is described here. The reads were assembled into contigs with a total size 2,898,501 bp. The genome information will be useful for further specific genetic studies of this strain to evaluate its immunomodulatory and biotechnological properties as a vaccine adjuvant.

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