ABSTRACT
Although abundant in soils, iron (Fe) is poorly bioavailable for plants. Improving Fe uptake in crops, enabling them to grow in Fe-depleted soils, has become a major focal interest. The secretion of Fe-mobilizing coumarins by plant roots recently emerged as an important factor allowing nongrass species to cope with low Fe bioavailability. The main molecular actors involved in the biosynthesis and secretion of coumarins have been identified, but the precise regulatory mechanisms that tune their production remain poorly understood. Here, we review the recent progress in coumarin synthesis and transport in plants and future research directions to gain knowledge of these mechanisms, which will offer novel opportunities for improving plant growth and health and for generating Fe-fortified crops.
Subject(s)
Arabidopsis , Arabidopsis/metabolism , Coumarins , Gene Expression Regulation, Plant , Iron/metabolism , Plant Roots/metabolism , SoilABSTRACT
Iron (Fe) is a major micronutrient and is required for plant growth and development. Nongrass species have evolved a reduction-based strategy to solubilize and take up Fe. The secretion of Fe-mobilizing coumarins (e.g. fraxetin, esculetin and sideretin) by plant roots plays an important role in this process. Although the biochemical mechanisms leading to their biosynthesis have been well described, very little is known about their cellular and subcellular localization or their mobility within plant tissues. Spectral imaging was used to monitor, in Arabidopsis thaliana, the in planta localization of Fe-mobilizing coumarins and scopolin. Molecular, genetic and biochemical approaches were also used to investigate the dynamics of coumarin accumulation in roots. These approaches showed that root hairs play a major role in scopoletin secretion, whereas fraxetin and esculetin secretion occurs through all epidermis cells. The findings of this study also showed that the transport of coumarins from the cortex to the rhizosphere relies on the PDR9 transporter under Fe-deficient conditions. Additional experiments support the idea that coumarins move throughout the plant body via the xylem sap and that several plant species can take up coumarins present in the surrounding media. Altogether, the data presented here demonstrate that coumarin storage and accumulation in roots is a highly complex and dynamic process.
Subject(s)
Arabidopsis Proteins , Arabidopsis , Coumarins , Plant RootsABSTRACT
Among the mineral nutrients that are required for plant metabolism, iron (Fe) and sulphur (S) play a central role as both elements are needed for the activity of several proteins involved in essential cellular processes. A combination of physiological, biochemical and molecular approaches was employed to investigate how S availability influences plant response to Fe deficiency, using the model plant Arabidopsis thaliana. We first observed that chlorosis symptom induced by Fe deficiency was less pronounced when S availability was scarce. We thus found that S deficiency inhibited the Fe deficiency induced expression of several genes associated with the maintenance of Fe homeostasis. This includes structural genes involved in Fe uptake (i.e. IRT1, FRO2, PDR9, NRAMP1) and transport (i.e. FRD3, NAS4) as well as a subset of their upstream regulators, namely BTS, PYE and the four clade Ib bHLH. Last, we found that the over accumulation of manganese (Mn) in response to Fe shortage was reduced under combined Fe and S deficiencies. These data suggest that S deficiency inhibits the Fe deficiency dependent induction of the Fe uptake machinery. This in turn limits the transport into the root and the plant body of potentially toxic divalent cations such as Mn and Zn, thus limiting the deleterious effect of Fe deprivation.
Subject(s)
Arabidopsis/metabolism , Iron Deficiencies , Sulfur/metabolism , Arabidopsis/genetics , Gene Expression Regulation, Plant , Homeostasis , Iron/metabolism , Transcription, GeneticABSTRACT
Iron (Fe) is an essential micronutrient for plant growth and development. Any defects in the maintenance of Fe homeostasis will alter plant productivity and the quality of their derived products. In Arabidopsis (Arabidopsis thaliana), the transcription factor ILR3 plays a central role in controlling Fe homeostasis. In this study, we identified bHLH121 as an ILR3-interacting transcription factor. Interaction studies showed that bHLH121 also interacts with the three closest homologs of ILR3 (i.e., basic-helix-loop-helix 34 [bHLH34], bHLH104, and bHLH115). bhlh121 loss-of-function mutants displayed severe defects in Fe homeostasis that could be reverted by exogenous Fe supply. bHLH121 acts as a direct transcriptional activator of key genes involved in the Fe regulatory network, including bHLH38, bHLH39, bHLH100, bHLH101, POPEYE, BRUTUS, and BRUTUS LIKE1, as well as IRONMAN1 and IRONMAN2 In addition, bHLH121 is necessary for activating the expression of transcription factor gene FIT in response to Fe deficiency via an indirect mechanism. bHLH121 is expressed throughout the plant body, and its expression is not affected by Fe availability. By contrast, Fe availability affects the cellular localization of bHLH121 protein in roots. Altogether, these data show that bHLH121 is a regulator of Fe homeostasis that acts upstream of FIT in concert with ILR3 and its closest homologs.
Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/metabolism , Basic Helix-Loop-Helix Transcription Factors/metabolism , Homeostasis/physiology , Iron/metabolism , Transcription Factors/metabolism , Arabidopsis/genetics , Arabidopsis Proteins/genetics , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors , Basic Helix-Loop-Helix Transcription Factors/genetics , Gene Expression Regulation, Plant , Gene Knockout Techniques , Gene Regulatory Networks , Homeostasis/genetics , Hydroponics , Nuclear Proteins , Plant Roots/genetics , Plant Roots/metabolism , Plants, Genetically Modified , Transcription Factors/genetics , Transcriptome , Ubiquitin-Protein LigasesABSTRACT
RNA silencing is a major antiviral defense mechanism in plants and invertebrates. Plant ARGONAUTE1 (AGO1) is pivotal in RNA silencing, and hence is a major target for counteracting viral suppressors of RNA-silencing proteins (VSRs). P0 from Turnip yellows virus (TuYV) is a VSR that was previously shown to trigger AGO1 degradation via an autophagy-like process. However, the identity of host proteins involved and the cellular site at which AGO1 and P0 interact were unknown. Here we report that P0 and AGO1 associate on the endoplasmic reticulum (ER), resulting in their loading into ER-associated vesicles that are mobilized to the vacuole in an ATG5- and ATG7-dependent manner. We further identified ATG8-Interacting proteins 1 and 2 (ATI1 and ATI2) as proteins that associate with P0 and interact with AGO1 on the ER up to the vacuole. Notably, ATI1 and ATI2 belong to an endogenous degradation pathway of ER-associated AGO1 that is significantly induced following P0 expression. Accordingly, ATI1 and ATI2 deficiency causes a significant increase in posttranscriptional gene silencing (PTGS) activity. Collectively, we identify ATI1 and ATI2 as components of an ER-associated AGO1 turnover and proper PTGS maintenance and further show how the VSR P0 manipulates this pathway.
Subject(s)
Argonaute Proteins/metabolism , Autophagy , Endoplasmic Reticulum/metabolism , Membrane Proteins/metabolism , Plant Proteins/metabolism , Viral Proteins/metabolism , Proteolysis , Vacuoles/metabolismABSTRACT
Iron (Fe) homeostasis is crucial for all living organisms. In mammals, an integrated posttranscriptional mechanism couples the regulation of both Fe deficiency and Fe excess responses. Whether in plants an integrated control mechanism involving common players regulates responses both to deficiency and to excess is still to be determined. In this study, molecular, genetic and biochemical approaches were used to investigate transcriptional responses to both Fe deficiency and excess. A transcriptional activator of responses to Fe shortage in Arabidopsis, called bHLH105/ILR3, was found to also negatively regulate the expression of ferritin genes, which are markers of the plant's response to Fe excess. Further investigations revealed that ILR3 repressed the expression of several structural genes that function in the control of Fe homeostasis. ILR3 interacts directly with the promoter of its target genes, and repressive activity was conferred by its dimerisation with bHLH47/PYE. Last, this study highlighted that important facets of plant growth in response to Fe deficiency or excess rely on ILR3 activity. Altogether, the data presented herein support that ILR3 is at the centre of the transcriptional regulatory network that controls Fe homeostasis in Arabidopsis, in which it acts as both transcriptional activator and repressor.
Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/genetics , Basic Helix-Loop-Helix Transcription Factors/metabolism , Iron/pharmacology , Transcription, Genetic , Arabidopsis/drug effects , Arabidopsis/growth & development , Arabidopsis Proteins/genetics , E-Box Elements/genetics , Ferritins/genetics , Ferritins/metabolism , Gene Expression Regulation, Plant/drug effects , Genes, Plant , Homeostasis , Models, Biological , Plant Leaves/drug effects , Plant Leaves/metabolism , Plant Roots/drug effects , Plant Roots/growth & development , Promoter Regions, Genetic/genetics , Protein Binding/drug effects , Seedlings/drug effects , Seedlings/growth & development , Transcription, Genetic/drug effectsABSTRACT
Iron is one of the most important micronutrients in plants as it is involved in many cellular functions (e.g., photosynthesis and respiration). Any defect in iron availability will affect plant growth and development as well as crop yield and plant product quality. Thus, iron homeostasis must be tightly controlled in order to ensure optimal absorption of this mineral element. Understanding mechanisms governing iron homeostasis in plants has been the focus of several studies during the past 10 years. These studies have greatly improved our understanding of the mechanisms involved, revealing a sophisticated iron-dependent transcriptional regulatory network. Strikingly, these studies have also highlighted that this regulatory web relies on the activity of numerous transcriptional regulators that belong to the same group of transcription factors (TF), the bHLH (basic helix-loop-helix) family. This is best exemplified in Arabidopsis where, to date, 16 bHLH TF have been characterized as involved in this process and acting in a complex regulatory cascade. Interestingly, among these bHLH TF some form specific clades, indicating that peculiar function dedicated to the maintenance of iron homeostasis, have emerged during the course of the evolution of the green lineage. Within this mini review, we present new insights on the control of iron homeostasis and the involvement of bHLH TF in this metabolic process.
ABSTRACT
Cecropin A is a natural antimicrobial peptide that exhibits fast and potent activity against a broad spectrum of pathogens and neoplastic cells, and that has important biotechnological applications. However, cecropin A exploitation, as for other antimicrobial peptides, is limited by their production and purification costs. Here, we report the efficient production of this bioactive peptide in rice bran using the rice oleosin 18 as a carrier protein. High cecropin A levels were reached in rice seeds driving the expression of the chimeric gene by the strong embryo-specific oleosin 18 own promoter, and targeting the peptide to the oil body organelle as an oleosin 18-cecropin A fusion protein. The accumulation of cecropin A in oil bodies had no deleterious effects on seed viability and seedling growth, as well as on seed yield. We also show that biologically active cecropin A can be easily purified from the transgenic rice seeds by homogenization and simple flotation centrifugation methods. Our results demonstrate that the oleosin fusion technology is suitable for the production of cecropin A in rice seeds, which can potentially be extended to other antimicrobial peptides to assist their exploitation.
Subject(s)
Antimicrobial Cationic Peptides/biosynthesis , Lipid Droplets/chemistry , Oryza/metabolism , Seeds/metabolism , Amino Acid Sequence , Antimicrobial Cationic Peptides/genetics , Genome, Plant , Mass Spectrometry , Molecular Sequence Data , Oryza/genetics , Phenotype , Plant Oils/chemistry , Plant Proteins/metabolism , Plants, Genetically Modified/metabolism , Promoter Regions, Genetic , Recombinant Fusion Proteins/metabolism , Seeds/genetics , TransgenesABSTRACT
Introducción: La biopsia renal percutánea es una herramienta fundamental para el manejo del paciente trasplantado renal. La prueba es primordial para detectar y/o prevenir cualquier disfunción en el injerto, siendo un procedimiento tanto diagnóstico como preconizador. Objetivo: Describir los cuidados de enfermería e identificar las complicaciones derivadas de la biopsia renal en los receptores de Trasplante Renal. Material y métodos: Estudio cuantitativo, descriptivo y transversal realizado en la Unidad de Trasplante Renal, Servicio de Nefrología, del 2008 al 2014. La población objeto de estudio son los receptores de Trasplante Renal (TR). La muestra está compuesta por 368 biopsias renales de seguimiento que ingresan para someterse a una biopsia renal. Los criterios de inclusión son ser mayores de 18 años, trasplantados y que han firmado el consentimiento informado. Se recogen datos sociodemográficos, clínico-asistenciales y complicaciones post-biopsia renal. Resultados: Desde 1980 hasta el 2014 se han llevado a cabo 1868 TR, de 2008 a 2014 se estudiaron 368 biopsias de seguimiento. Se monitoriza la Tensión Arterial y la coagulación pre biopsia. Tras el procedimiento, se controla la presencia de sangrado por micción y constantes vitales. Inicialmente el reposo absoluto era de 24 h, a partir de 2014 se reduce a 6 horas, recomendando reposo relativo al alta, las complicaciones fueron mínimas. Conclusiones: Los resultados indican que la biopsia renal es un procedimiento eficaz, con escasas complicaciones. Destacar el papel de enfermería en la detección precoz de complicaciones (AU)
Introduction: Percutaneous Renal Biopsy is an essential tool for the management of renal transplant patients. The test is essential to detect and / or prevent any graft dysfunction, being both a diagnostic and preconizador procedure. Objective is to describe nursing care and identify complications of renal biopsy in renal transplant recipients. Methods: A quantitative, descriptive and transversal study was carried out in the Renal Transplantation Unit, Nephrology Department of Puigvert Foundation, from 2008 to 2014. The study population is kidney transplant recipients (TR). The sample consists of 368 kidney biopsies follow-up. Inclusion criteria are being over 18 years, transplanted, and signed informed consent. Sociodemographic data, clinical care and complications after renal biopsy are collected. Results: From 1980 to 2014 were carried out 1868 TR of 2008-2014 368 follow-up biopsies were studied. Blood Pressure and pre biopsy coagulation were monitored. After the procedure, the presence of bleeding urination and vital signs monitored. Initially absolute rest was 24 h, since 2014 was reduced to 6 hours, recommending rest relative to high, complications were minimal. Conclusions: The results indicate that renal biopsy is an effective procedure with few complications. The nursing role in the early detection of complications is important (AU)
Subject(s)
Female , Humans , Male , Kidney Transplantation/nursing , Biopsy/methods , Biopsy/nursing , Hematoma/nursing , Hematuria/nursing , Nursing Care/methods , Nursing Care , Nephrology Nursing/methods , 24960/methods , Hematoma/complications , Hematoma/prevention & control , Hematuria/complications , Hematuria/prevention & control , Cross-Sectional Studies/methods , Follow-Up Studies , Data Collection/methods , Data Collection/statistics & numerical data , Epidemiology, DescriptiveABSTRACT
La mejora de la calidad de vida está relacionada con los cambios demográficos mundiales y a su vez con los avances médicos, tecnológicos, los hábitos alimentarios y las condiciones de vida. El objetivo de este estudio descriptivo es comprobar si el receptor de un trasplante renal mayor de 65 años cambia su percepción acerca de la calidad de vida a corto y a largo plazo. La población diana fueron los receptores mayores de 65 años que acudieron a la Fundación Puigvert y a quienes el trasplante renal les fue practicado entre septiembre y noviembre de 2007. La muestra inicial, en 2009, estaba compuesta por 31 pacientes, quedando para 2012 una muestra de 16 receptores. Los instrumentos de recolección de información fueron una encuesta de 11 ítems y el cuestionario SF-36. El procedimiento del estudio consistió en responder la encuesta de 11 ítems confeccionada concretamente para el estudio y el cuestionario de calidad de vida SF-36. Ambos fueron respondidos mediante entrevista telefónica. Su duración fue de 15 a 20 minutos. Se establecen dos tiempos: el primero, durante los meses de septiembre, octubre y noviembre de 2007, y el segundo, de diciembre de 2011 a marzo de 2012. Los resultados obtenidos muestran una diferencia: con reducción de un 11.8% entre 2009 y 2012 en la salud física y de un 8.5% en la salud mental. Como conclusión, el trasplante renal es la mejor opción entre los tratamientos sustitutivos de la función renal.
Improvement in quality of life is related to global demographic changes and also to medical and tech-nological advances, patients eating habits and living conditions. The purpose of this descriptive study is to know whether kidney transplant recipients older than 65 years of age perceive any difference in the quality of their lives in both the short and long term. Target populations were kidney recipients over 65 years visiting the Puigvert Foundation. Patients had received their kidney transplant between September and November 2007. The initial sample, in 2009, included 31 patients; another sample of 16 kidney receptors was left for 2012. Data collection tools were an 11-item survey and the SF-36 questionnaire. The procedure for the study consisted in answering the 11-item survey specifically developed for this study, and the quality of life SF-36 questionnaire. Answers were collected by means of a telephone interview. Duration of interview was between 15 to 20 minutes. Two time periods were established for data analysis: the first, during the months of September, October and November 2007, and the second, from December 2011 to March 2012. The results reveal an 11.8% decline in physical health and an 8.5% decline in mental health between 2009 and 2012. In conclusion, kidney transplantation is the best choice among renal substitution therapies.
Subject(s)
Humans , Aged , Quality of Life , Kidney Transplantation , Review Literature as Topic , Pan American Health Organization , Mental HealthABSTRACT
BACKGROUND: Cecropin A is a natural antimicrobial peptide that exhibits rapid, potent and long-lasting lytic activity against a broad spectrum of pathogens, thus having great biotechnological potential. Here, we report a system for producing bioactive cecropin A in rice seeds. RESULTS: Transgenic rice plants expressing a codon-optimized synthetic cecropin A gene drived by an endosperm-specific promoter, either the glutelin B1 or glutelin B4 promoter, were generated. The signal peptide sequence from either the glutelin B1 or the glutelin B4 were N-terminally fused to the coding sequence of the cecropin A. We also studied whether the presence of the KDEL endoplasmic reticulum retention signal at the C-terminal has an effect on cecropin A subcellular localization and accumulation. The transgenic rice plants showed stable transgene integration and inheritance. We show that cecropin A accumulates in protein storage bodies in the rice endosperm, particularly in type II protein bodies, supporting that the glutelin N-terminal signal peptides play a crucial role in directing the cecropin A to this organelle, independently of being tagged with the KDEL endoplasmic reticulum retention signal. The production of cecropin A in transgenic rice seeds did not affect seed viability or seedling growth. Furthermore, transgenic cecropin A seeds exhibited resistance to infection by fungal and bacterial pathogens (Fusarium verticillioides and Dickeya dadantii, respectively) indicating that the in planta-produced cecropin A is biologically active. CONCLUSIONS: Rice seeds can sustain bioactive cecropin A production and accumulation in protein bodies. The system might benefit the production of this antimicrobial agent for subsequent applications in crop protection and food preservation.
Subject(s)
Antimicrobial Cationic Peptides/biosynthesis , Endosperm/metabolism , Oryza/metabolism , Amino Acid Sequence , Antimicrobial Cationic Peptides/chemistry , Disease Resistance/immunology , Fusarium/physiology , Gene Dosage , Molecular Sequence Data , Mutagenesis, Insertional , Organ Specificity/genetics , Organelles/metabolism , Plant Diseases/immunology , Plant Diseases/microbiology , Plants, Genetically Modified , Reproducibility of Results , Subcellular Fractions/metabolism , Transgenes/geneticsABSTRACT
The important viscosity of the respiratory tract mucus of Cystic fibrosis (CF) patients impairs the mucociliary transport system and allows the growth of numerous micro-organisms. Among them, Pseudomonas aeruginosa and Staphylococcus aureus are known to be responsible for pulmonary infections. We imagined that CF microflora could also harbour micro-organisms naturally equipped to compete with these pathogens. A method was developed to recover these antibiotic-producing strains within 20 CF sputum. Using this approach, we have isolated an unusual Gram-positive bacterium identified as Paenibacillus alvei by Api galleries and 16S rRNA gene sequence analysis. This strain has inhibited the growth of P. aeruginosa, S. aureus and Klebsiella pneumoniae, in co-cultures. A liquid mineral medium named MODT50 was designed and optimised for the production and the recovery of the antimicrobial compounds. The supernatant has inhibited the growth of all Gram-positive strains tested, even Methicillin-resistant S. aureus. One antimicrobial compound with a peptide structure (mainly active against S. aureus, Micrococcus luteus, and Pseudomonas stutzeri) has been purified and characterised by liquid chromatography-mass spectrometry. The new active molecule (m/z 786.6) named depsipeptide L possesses a 15-guanidino-3-hydroxypentadecanoic acid side chain (m/z 298) linked on a cyclic part of four amino acids residues (Ser, two Leu/Ile, Arg). This work reports for the first time the production of such a molecule by a P. alvei strain in a mineral medium. The CF lung microflora might represent a valuable source for the discovery of new antimicrobial-producing strains.
ABSTRACT
BACKGROUND: Lactic acid bacteria are commonly marketed as probiotics based on their putative or proven health-promoting effects. These effects are known to be strain specific but the underlying molecular mechanisms remain poorly understood. Therefore, unravelling the determinants behind probiotic features is of particular interest since it would help select strains that stand the best chance of success in clinical trials. Bile tolerance is one of the most crucial properties as it determines the ability of bacteria to survive in the small intestine, and consequently their capacity to play their functional role as probiotics. In this context, the objective of this study was to investigate the natural protein diversity within the Lactobacillus plantarum species with relation to bile tolerance, using comparative proteomics. RESULTS: Bile tolerance properties of nine L. plantarum strains were studied in vitro. Three of them presenting different bile tolerance levels were selected for comparative proteomic analysis: L. plantarum 299 V (resistant), L. plantarum LC 804 (intermediate) and L. plantarum LC 56 (sensitive). Qualitative and quantitative differences in proteomes were analyzed using two-dimensional electrophoresis (2-DE), tryptic digestion, liquid chromatography-mass spectrometry analysis and database search for protein identification. Among the proteins correlated with differences in the 2-DE patterns of the bacterial strains, 15 have previously been reported to be involved in bile tolerance processes. The effect of a bile exposure on these patterns was investigated, which led to the identification of six proteins that may be key in the bile salt response and adaptation in L. plantarum: two glutathione reductases involved in protection against oxidative injury caused by bile salts, a cyclopropane-fatty-acyl-phospholipid synthase implicated in maintenance of cell envelope integrity, a bile salt hydrolase, an ABC transporter and a F0F1-ATP synthase which participate in the active removal of bile-related stress factors. CONCLUSIONS: These results showed that comparative proteomic analysis can help understand the differential bacterial properties of lactobacilli. In the field of probiotic studies, characteristic proteomic profiles can be identified for individual properties that may serve as bacterial biomarkers for the preliminary selection of strains with the best probiotic potential.
Subject(s)
Anti-Bacterial Agents/metabolism , Bacterial Proteins/analysis , Bile Acids and Salts/metabolism , Lactobacillus plantarum/chemistry , Lactobacillus plantarum/drug effects , Proteome/analysis , Stress, Physiological , Chromatography, Liquid , Electrophoresis, Gel, Two-Dimensional , Gene Expression Regulation, Bacterial , Mass SpectrometryABSTRACT
Enterococcus faecalis WHE 96, a strain isolated from soft cheese based on its anti-Listeria activity, produced a 5,494-Da bacteriocin that was purified to homogeneity by ultrafiltration and cation-exchange and reversed-phase chromatographies. The amino acid sequence of this bacteriocin, named enterocin 96, was determined by Edman degradation, and its structural gene was sequenced, revealing a double-glycine leader peptide. After a comparison with other bacteriocins, it was shown that enterocin 96 was a new class II bacteriocin that showed very little similarity with known structures. Enterocin 96 was indeed a new bacteriocin belonging to class II bacteriocins. The activity spectrum of enterocin 96 covered a wide range of bacteria, with strong activity against most gram-positive strains but very little or no activity against gram-negative strains.
Subject(s)
Anti-Bacterial Agents/metabolism , Bacterial Proteins/metabolism , Cheese/microbiology , Enterococcus faecalis/metabolism , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Bridged-Ring Compounds/metabolism , Bridged-Ring Compounds/pharmacology , Enterococcus faecalis/genetics , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Molecular Sequence Data , Protein Sorting Signals , Sequence Analysis, DNA , Sequence Analysis, Protein , Sequence Homology, Amino AcidABSTRACT
The identification of cell components involved in probiotic activities is a challenge in current probiotic research. In this work, a new approach based on proteomics as an analytical tool for the identification of characteristic protein profiles related to adhesion to mucin as a model probiotic property was used. Three Lactobacillus plantarum strains with different adhesion rates were used for proteomic analysis: L. plantarum WHE 92 (15.9%), L. plantarum 299 v (9.1%) and L. plantarum CECT 4185 (1.4%). Cell wall extracts were subjected to proteomic analysis of differential protein expression using 2-DE, tryptic digestion, chip-LC-QTOF mass analysis and protein identification using database search. Several proteins, previously reported to be involved in bacterial adhesion: elongation factor EF-Tu, GroEL chaperonin, molecular chaperone DnaK and glyceraldehyde-3-phosphate dehydrogenase were found to be overexpressed in the cell wall proteome of the highly adhesive strain L. plantarum WHE 92. The overexpression of two spots containing GroES co-chaperonin in the most adhesive strain also suggested the involvement of this protein in the adhesion process. The association of proteomic profiles and proteins with particular probiotic properties opens the way for the use of such profiles and proteins as bacterial biomarkers for the properties of bacteria but probably also for their potential health effects.
Subject(s)
Biomarkers/analysis , Cell Adhesion , Electrophoresis, Gel, Two-Dimensional , Lactobacillus plantarum/chemistry , Mass Spectrometry , Probiotics/chemistry , Analysis of Variance , Animals , Bacterial Proteins/analysis , Cell Wall , Chaperonin 10/analysis , Lactobacillus plantarum/metabolism , Mucins/metabolism , SwineABSTRACT
Enterococcus faecium IT62, a strain isolated from ryegrass in Japan, produces three bacteriocins (enterocins L50A, L50B, and IT) that have been previously purified and the primary structures of which have been determined by amino acid sequencing (E. Izquierdo, A. Bednarczyk, C. Schaeffer, Y. Cai, E. Marchioni, A. Van Dorsselaer, and S. Ennahar, Antimicrob. Agents Chemother., 52:1917-1923, 2008). Genetic analysis showed that the bacteriocins of E. faecium IT62 are plasmid encoded, but with the structural genes specifying enterocin L50A and enterocin L50B being carried by a plasmid (pTAB1) that is separate from the one (pTIT1) carrying the structural gene of enterocin IT. Sequencing analysis of a 1,475-bp region from pTAB1 identified two consecutive open reading frames corresponding, with the exception of 2 bp, to the genes entL50A and entL50B, encoding EntL50A and EntL50B, respectively. Both bacteriocins are synthesized without N-terminal leader sequences. Genetic analysis of a sequenced 1,380-bp pTIT1 fragment showed that the genes entIT and entIM, encoding enterocin IT and its immunity protein, respectively, were both found in E. faecium VRE200 for bacteriocin 32. Enterocin IT, a 6,390-Da peptide made up of 54 amino acids, has been previously shown to be identical to the C-terminal part of bacteriocin 32, a 7,998-Da bacteriocin produced by E. faecium VRE200 whose structure was deduced from its structural gene (T. Inoue, H. Tomita, and Y. Ike, Antimicrob. Agents Chemother., 50:1202-1212, 2006). By combining the biochemical and genetic data on enterocin IT, it was concluded that bacteriocin 32 is in fact identical to enterocin IT, both being encoded by the same plasmid-borne gene, and that the N-terminal leader peptide for this bacteriocin is 35 amino acids long and not 19 amino acids long as previously reported.
Subject(s)
Bacteriocins , Enterococcus faecium/metabolism , Amino Acid Sequence , Bacteriocins/chemistry , Bacteriocins/classification , Bacteriocins/genetics , Bacteriocins/metabolism , Base Sequence , DNA, Bacterial/analysis , DNA, Bacterial/genetics , DNA, Bacterial/isolation & purification , Enterococcus faecium/genetics , Enterococcus faecium/isolation & purification , Lolium/microbiology , Molecular Sequence Data , Multigene Family , Plasmids/genetics , Polymerase Chain Reaction , Sequence Analysis, DNAABSTRACT
La calidad de vida se define como la percepción personal de un individuo de su situación de vida, dentro del contexto cultural y de valores en el que vive, y en relación con sus objetivos, expectativas, valores e intereses. El objetivo de este trabajo es conocer la calidad de vida de los pacientes trasplantados renales mayores de 65 años. Estudio cualitativo, descriptivo y retrospectivo. La muestra abarcó un total de 31 pacientes mayores de 65 años que fueron trasplantados en nuestro centro desde julio de 2003 hasta julio de 2006. El instrumento de recogida de información fue doble: una encuesta de 11 ítems y el cuestionario SF-36.El aspecto peor valorado por los encuestados (51,6 puntos) se refería a la capacidad de realizar un esfuerzo físico intenso. Sin embargo, actividades de menor intensidad recibieron una puntuación más elevada (88,7 puntos). Los pacientes mayores de 65 años que han recibido un trasplante renal, perciben una mejoría importante en su calidad de vida respecto al período anterior. Esto se refleja en una ampliación del abanico de actividades a realizer (AU)
Quality of life is defined as the personal perception of an individual of his or her life situation, within the cultural context and the context of the values in which he or she lives, and in relation to his orher goals, expectations, values and interests. The aim of this study is to determine the quality of life of patients over 65 years of age who have undergone kidney transplants. A qualitative, descriptive and retrospective study. The sample encompassed a total of 31 patients aged over 65 who received kidney transplants at our centre between July 2003 and July 2006. The instrument used to compile the information was in two parts: a survey of 11 items and questionnaire SF-36.The aspect that received the lowest rating from the patients surveyed (51.6 points) related to the capacity for intense physical efforts. However, activities of lower intensity received a higher score (88.7 points). Patients aged over 65 who have received a kidney transplant perceive an important improvement in their quality of life compared to the period prior to the transplant. This is reflected in an extension of the range of activities they can carry out (AU)
Subject(s)
Humans , Male , Female , Aged , Renal Insufficiency, Chronic/psychology , Kidney Transplantation/psychology , Quality of Life , Health SurveysABSTRACT
Enterococcus faecium WHE 81, a multi-bacteriocin producer, was tested for its antimicrobial activity on Listeria monocytogenes in Munster cheese, a red smear soft cheese. The naturally delayed and superficial contamination of this type of cheese allowed the use of E. faecium WHE 81 at the beginning of the ripening as a surface culture. A brine solution inoculated at 10(5)CFU of E. faecium WHE 81 per mL was sprayed on the cheese surface during the first smearing operation. On day 7, smearing of cheese samples with a brine solution at 10(2)CFU of L. monocytogenes per mL yielded initial cell counts of approximately 50 CFU g(-1) of the pathogen on the cheese surface. Although, in some instances, L. monocytogenes could survive (<50 CFU g(-1)) in the presence of E. faecium WHE 81, it was unable to initiate growth. In control samples however, L. monocytogenes counts often exceeded 10(4) CFU g(-1). In other respects, E. faecium WHE 81, which naturally existed in Munster cheese, did not adversely impact on the ripening process.
Subject(s)
Antibiosis , Bacteriocins/biosynthesis , Cheese/microbiology , Enterococcus faecium/physiology , Listeria monocytogenes/growth & development , Bacteriocins/pharmacology , Cheese/standards , Colony Count, Microbial , Consumer Product Safety , Enterococcus faecium/metabolism , Fermentation , Food Contamination/prevention & control , Food Microbiology , Listeria monocytogenes/drug effectsABSTRACT
Enterococcus faecium IT62, isolated from ryegrass in Japan, was shown to produce three different bacteriocins, two of which had molecular masses and amino acid sequences that corresponded to those of enterocin L50A and enterocin L50B. These peptides existed, however, as chemically modified forms that were either N formylated or N formylated and oxidized at Met(24). The third bacteriocin, named enterocin IT, had a molecular mass of 6,390 Da, was made up of 54 amino acids, and did not correspond to any known bacteriocin. However, enterocin IT was identical to the C-terminal part of the 16-amino-acid-longer bacteriocin 32 (T. Inoue, H. Tomita, and Y. Ike, Antimicrob. Agents Chemother., 50:1202-1212, 2006). For the first time, the antimicrobial activity spectra for enterocins L50A and L50B were determined separately and included a wide range of gram-positive bacteria but also a few gram-negative strains that were weakly sensitive. Slight differences in the activities of enterocins L50A and L50B were observed, as gram-positive bacteria showed an overall higher level of sensitivity to L50A than to L50B, as opposed to gram-negative ones. Conversely, enterocin IT showed a very narrow antimicrobial spectrum that was limited to E. faecium strains, one strain of Bacillus subtilis, and one strain of Lactococcus lactis. This study showed that E. faecium IT62, a grass-borne strain, produces bacteriocins with very different activity features and structures that may be found in strains associated with food or those of clinical origin, which demonstrates that a particular enterocin structure may be widespread and not related to the producer's origin.