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1.
Foods ; 13(7)2024 Apr 07.
Article in English | MEDLINE | ID: mdl-38611424

ABSTRACT

A growing interest in the recovery and enhancement of crops, particularly local varieties such as 'Caaveiro' wheat, has been observed. This study aims to investigate the impact of cultivation systems (organic versus conventional) on the nutritional quality of 'Caaveiro' flour and breads protected by the PGI "Pan Galego," employing two fermentation methods (sourdough versus sourdough and biological yeast). Organic flour exhibited significantly higher levels of moisture, fat, sucrose, phosphorus (P), sodium (Na), and copper (Cu) while also exhibiting a lower total starch and zinc (Zn) content. Organic bread, produced using both fermentation methods, demonstrated significantly higher protein, carbohydrate, total, resistant, and rapidly digestible starch, ash, Na, P, iron (Fe), and Cu content. Additionally, they contained less moisture compared to conventional bread. Despite variations in nutritional characteristics based on the cultivation system, the organic approach proved effective at producing high-quality products with a positive environmental impact, which is highly appreciated by consumers.

2.
Theor Appl Genet ; 136(12): 244, 2023 Nov 13.
Article in English | MEDLINE | ID: mdl-37957405

ABSTRACT

KEY MESSAGE: Association mapping conducted in 189 Spanish bread wheat landraces revealed six key genomic regions that constitute stable QTLs for yield and include 15 candidate genes. Genetically diverse landraces provide an ideal population to conduct association analysis. In this study, association mapping was conducted in a collection of 189 Spanish bread wheat landraces whose genomic diversity had been previously assessed. These genomic data were combined with characterization for yield-related traits, including grain size and shape, and phenological traits screened across five seasons. The association analysis revealed a total of 881 significant marker trait associations, involving 434 markers across the genome, that could be grouped in 366 QTLs based on linkage disequilibrium. After accounting for days to heading, we defined 33 high density QTL genomic regions associated to at least four traits. Considering the importance of detecting stable QTLs, 6 regions associated to several grain traits and thousand kernel weight in at least three environments were selected as the most promising ones to harbour targets for breeding. To dissect the genetic cause of the observed associations, we studied the function and in silico expression of the 413 genes located inside these six regions. This identified 15 candidate genes that provide a starting point for future analysis aimed at the identification and validation of wheat yield related genes.


Subject(s)
Genome-Wide Association Study , Triticum , Chromosome Mapping , Triticum/genetics , Bread , Plant Breeding , Phenotype , Edible Grain/genetics , Genomics
3.
bioRxiv ; 2023 Oct 26.
Article in English | MEDLINE | ID: mdl-37961346

ABSTRACT

Purines and their derivatives are key molecules for controlling intracellular energy homeostasis and nucleotide synthesis. In eukaryotes, including humans, purines also act as signaling molecules that mediate extracellular communication and control key cellular processes, such as proliferation, migration, differentiation, and apoptosis. However, the signaling role of purines in bacteria is largely unknown. Here, by combining structural and sequence information, we define a purine-binding motif, which is present in sensor domains of thousands of bacterial receptors that modulate motility, gene expression, metabolism and second messenger turnover. The screening of compound libraries and microcalorimetric titrations of selected sensor domains validated their ability to specifically bind purine derivatives. The physiological relevance of purine sensing was demonstrated in a second messenger signaling system that modulates c-di-GMP levels.

4.
Front Microbiol ; 14: 1110360, 2023.
Article in English | MEDLINE | ID: mdl-36819031

ABSTRACT

Antimicrobial resistance is a natural and inevitable phenomenon that constitutes a severe threat to global public health and economy. Innovative products, active against new targets and with no cross- or co-resistance with existing antibiotic classes, novel mechanisms of action, or multiple therapeutic targets are urgently required. For these reasons, antimicrobial peptides such as bacteriocins constitute a promising class of new antimicrobial drugs under investigation for clinical development. Here, we review the potential therapeutic use of AS-48, a head-to-tail cyclized cationic bacteriocin produced by Enterococcus faecalis. In the last few years, its potential against a wide range of human pathogens, including relevant bacterial pathogens and trypanosomatids, has been reported using in vitro tests and the mechanism of action has been investigated. AS-48 can create pores in the membrane of bacterial cells without the mediation of any specific receptor. However, this mechanism of action is different when susceptible parasites are studied and involves intracellular targets. Due to these novel mechanisms of action, AS-48 remains active against the antibiotic resistant strains tested. Remarkably, the effect of AS-48 against eukaryotic cell lines and in several animal models show little effect at the doses needed to inhibit susceptible species. The characteristics of this molecule such as low toxicity, microbicide activity, blood stability and activity, high stability at a wide range of temperatures or pH, resistance to proteases, and the receptor-independent effect make AS-48 unique to fight a broad range of microbial infections, including bacteria and some important parasites.

5.
Foods ; 11(20)2022 Oct 12.
Article in English | MEDLINE | ID: mdl-37430925

ABSTRACT

The most consumed cereal-based product worldwide is bread. "Caaveiro", an autochthonous variety with a recent growing interest, is one of the wheat varieties that fulfill the 25% local flour requirement in the PGI "Pan Galego" bread baking industry. The element content of the refined wheat flours used to make "Pan Galego" (''Caaveiro'', FCv; Castilla, FC; and a mixture of both, FM) was evaluated in ICP-MS. In addition, wholegrain flour (FWM) was included in the analysis. Loaves of bread were made with these flours (a, 100% FC; b, 100% FCv); and c, FM: 75% FC + 25% FCv) and their element content was analyzed. Wholegrain flour ranked the highest in almost all elements, highlighting the P (494.80 mg/100 g), while the FM and the FC presented the opposite behavior, with the highest Se values (14.4 and 15.8 mg/100 g, respectively). FCv was situated in an intermediate position regarding P, K, Mg, Mn, Zn, Fe and Na content, standing closer to FWM, although it presents the highest values for Cu (1076.3 µg/100 g). The differences observed in flour were maintained in bread. Hence, the local cultivar ''Caaveiro'' has an interesting nutritional profile from the point of view of the element content.

6.
EJIFCC ; 32(2): 286-291, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34421497

ABSTRACT

Malignant hyperthermia is a pharmacogenetic disorder. It manifests as a hypercatabolic skeletal muscle syndrome linked to inhaled volatile anesthetics or depolarizing muscle relaxants. Its clinical signs and symptoms are tachycardia, hyperthermia, hypercapnia, acidosis, muscle rigidity, rhabdomyolysis, hyperkalemia, arrhythmia and renal failure. Mortality without specific treatment is 80% and decreases to 5% with the use of dantrolene sodium. This article presents the case of a 39-year-old patient admitted to the Intensive Care Unit for malignant hyperthermia after surgery for septoplasty plus turbinoplasty.

7.
Int J Mol Sci ; 22(12)2021 Jun 12.
Article in English | MEDLINE | ID: mdl-34204625

ABSTRACT

Bacteria have evolved sophisticated signaling mechanisms to coordinate interactions with organisms of other domains, such as plants, animals and human hosts. Several important signal molecules have been identified that are synthesized by members of different domains and that play important roles in inter-domain communication. In this article, we review recent data supporting that histamine is a signal molecule that may play an important role in inter-domain and inter-species communication. Histamine is a key signal molecule in humans, with multiple functions, such as being a neurotransmitter or modulator of immune responses. More recent studies have shown that bacteria have evolved different mechanisms to sense histamine or histamine metabolites. Histamine sensing in the human pathogen Pseudomonas aeruginosa was found to trigger chemoattraction to histamine and to regulate the expression of many virulence-related genes. Further studies have shown that many bacteria are able to synthesize and secrete histamine. The release of histamine by bacteria in the human gut was found to modulate the host immune responses and, at higher doses, to result in host pathologies. The elucidation of the role of histamine as an inter-domain signaling molecule is an emerging field of research and future investigation is required to assess its potential general nature.


Subject(s)
Bacteria/metabolism , Histamine/metabolism , Signal Transduction , Animals , Bacteria/genetics , Histamine Release , Humans , Models, Biological , Models, Molecular
8.
Plants (Basel) ; 10(4)2021 Apr 03.
Article in English | MEDLINE | ID: mdl-33916820

ABSTRACT

In the context of a general genetics course, mathematical descriptions of Mendelian inheritance and population genetics are sometimes discouraging and students often have serious misconceptions. Innovative strategies in expositive classes can clearly encourage student's motivation and participation, but laboratories and practical classes are generally the students' favourite academic activities. The design of lab practices focused on learning abstract concepts such as genetic interaction, genetic linkage, genetic recombination, gene mapping, or molecular markers is a complex task that requires suitable segregant materials. The optimal population for pedagogical purposes is an F2 population, which is extremely useful not only in explaining different key concepts of genetics (as dominance, epistasis, and linkage) but also in introducing additional curricular tools, particularly concerning statistical analysis. Among various model organisms available, barley possesses several unique features for demonstrating genetic principles. Therefore, we generated a barley F2 population from the parental lines of the Oregon Wolfe Barley collection. The objective of this work is to present this F2 population as a model to teach Mendelian genetics in a medium-high-level genetics course. We provide an exhaustive phenotypic and genotypic description of this plant material that, together with a description of the specific methodologies and practical exercises, can be helpful for transferring our fruitful experience to anyone interested in implementing this educational resource in his/her teaching.

9.
Plants (Basel) ; 10(4)2021 Mar 24.
Article in English | MEDLINE | ID: mdl-33805170

ABSTRACT

Modern plant-breeding practices have narrowed the genetic base of wheat, such that there is a need to introduce new germplasms with underexploited diversity into breeding programs. Wheat landraces are a very valuable resource when searching for genetic variation, which not only possess increased adaptability, but also quality-related traits. Several studies have shown a wide genetic diversity in Spanish wheat landraces compared to other germplasm collections; therefore, the main objective of this study is to analyze the variability in a collection of 189 landraces from the Spanish National Plant Genetic Resources Centre (Centro de Recursos Fitogenéticos, CRF-INIA, Alcalá de Henares), in relation to end-use quality traits. We characterized the whole collection for high-molecular-weight glutenin and puroindoline allelic composition, and for gluten strength. In addition, grain protein content, grains per spike, and thousand kernel weight were evaluated in samples from four-year field trials. The relationship between glutenin composition and quality was evaluated, and some alleles strongly associated with high quality were identified in the collection, some of them specific for Iberian landraces. The results also show the presence of novel variability within high-molecular-weight glutenin and puroindolines, which needs to be characterized further in order to assess its influence on wheat quality. In addition, a set of landraces showing outstanding values for gluten quality and a good agronomic performance was selected for testing in field trials in order to evaluate the suitability of their direct use in cropping systems.

10.
FEBS J ; 288(7): 2294-2310, 2021 04.
Article in English | MEDLINE | ID: mdl-33021055

ABSTRACT

Signalling through chemosensory pathways is typically initiated by the binding of signal molecules to the chemoreceptor ligand binding domain (LBD). The PcaY_PP chemoreceptor from Pseudomonas putida KT2440 is characterized by an unusually broad signal range, and minimal requisites for signal binding are the presence of a C6-membered ring and that of a carboxyl group. Previous studies have shown that only some of the multiple signals recognized by this chemoreceptor are of apparent metabolic value. We report here high-resolution structures of PcaY_PP-LBD in the absence and presence of four cognate chemoeffectors and glycerol. The domain formed a four-helix bundle (4HB), and both ligand binding sites of the dimer were occupied with the high-affinity ligands protocatechuate and quinate, whereas the lower-affinity ligands benzoate and salicylate were present in only one site. Ligand binding was verified by microcalorimetric titration of site-directed mutants revealing important roles of an arginine and number of polar residues that establish an extensive hydrogen bonding network with bound ligands. The comparison of the apo and holo structures did not provide evidence for this receptor employing a transmembrane signalling mechanism that involves piston-like shifts of the final helix. Instead, ligand binding caused rigid-body scissoring movements of both monomers of the dimer. Comparisons with the 4HB domains of the Tar and Tsr chemoreceptors revealed significant structural differences. Importantly, the ligand binding site in PcaY_PP-LBD is approximately 8 Å removed from that of the Tar and Tsr receptors. Data indicate a significant amount of structural and functional diversity among 4HB domains. DATABASES: The coordinates and structure factors have been deposited in the protein data band with the following IDs: 6S1A (apo form), 6S18 (bound glycerol), 6S33 (bound protocatechuate), 6S38 (bound quinate), 6S3B (bound benzoate) and 6S37 (bound salicylate).


Subject(s)
Bacterial Proteins/ultrastructure , Chemoreceptor Cells/ultrastructure , Protein Conformation , Pseudomonas putida/ultrastructure , Bacterial Proteins/chemistry , Binding Sites/genetics , Chemoreceptor Cells/chemistry , Crystallography, X-Ray , Ligands , Models, Molecular , Mutation/genetics , Protein Binding/genetics , Protein Domains/genetics , Protein Multimerization , Pseudomonas putida/chemistry , Signal Transduction
11.
Sci Rep ; 10(1): 14008, 2020 08 19.
Article in English | MEDLINE | ID: mdl-32814825

ABSTRACT

The primary aim of this study was to investigate the functional, physiological and subjective responses to NMES exercise in cancer patients. Participants with a cancer diagnosis, currently undergoing treatment, and an had an Eastern Cooperative Oncology Group (ECOG) performance status (ECOG) of 1 and 2 were recommended to participate by their oncologist. Following a 2-week, no-NMES control period, each participant was asked to undertake a concurrent NMES exercise intervention over a 4-week period. Functional muscle strength [30 s sit-to-stand (30STS)], mobility [timed up and go (TUG)], exercise capacity [6-min walk test (6MWT)] and health related quality of life (HR-QoL) were assessed at baseline 1 (BL1), 2-week post control (BL2) and post 4-week NMES exercise intervention (POST). Physiological and subjective responses to LF-NMES were assessed during a 10-stage incremental session, recorded at BL2 and POST. Fourteen participants [mean age: 62 years (10)] completed the intervention. No adverse events were reported. 30STS (+ 2.4 reps, p = .007), and 6MWT (+ 44.3 m, p = .028) significantly improved after the intervention. No changes in TUG or HR-QoL were observed at POST. Concurrent NMES exercise may be an effective exercise intervention for augmenting physical function in participants with cancer and moderate and poor functional status. Implications for cancer survivors: By allowing participants to achieve therapeutic levels of exercise, concurrent NMES may be an effective supportive intervention in cancer rehabilitation.


Subject(s)
Cancer Survivors/statistics & numerical data , Electric Stimulation Therapy/methods , Exercise Therapy/methods , Exercise/physiology , Neoplasms/rehabilitation , Neuromuscular Junction/physiology , Aged , Female , Humans , Male , Middle Aged , Muscle Strength/physiology , Neoplasms/physiopathology , Neoplasms/therapy , Outcome Assessment, Health Care/methods , Outcome Assessment, Health Care/statistics & numerical data , Prospective Studies , Quadriceps Muscle/physiology , Quality of Life , Surveys and Questionnaires , Walk Test/methods
12.
BMC Genomics ; 21(1): 122, 2020 Feb 04.
Article in English | MEDLINE | ID: mdl-32019507

ABSTRACT

BACKGROUND: One of the main goals of the plant breeding in the twenty-first century is the development of crop cultivars that can maintain current yields in unfavorable environments. Landraces that have been grown under varying local conditions include genetic diversity that will be essential to achieve this objective. The Center of Plant Genetic Resources of the Spanish Institute for Agriculture Research maintains a broad collection of wheat landraces. These accessions, which are locally adapted to diverse eco-climatic conditions, represent highly valuable materials for breeding. However, their efficient use requires an exhaustive genetic characterization. The overall aim of this study was to assess the diversity and population structure of a selected set of 380 Spanish landraces and 52 reference varieties of bread and durum wheat by high-throughput genotyping. RESULTS: The DArTseq GBS approach generated 10 K SNPs and 40 K high-quality DArT markers, which were located against the currently available bread and durum wheat reference genomes. The markers with known locations were distributed across all chromosomes with relatively well-balanced genome-wide coverage. The genetic analysis showed that the Spanish wheat landraces were clustered in different groups, thus representing genetic pools providing a range of allelic variation. The subspecies had a major impact on the population structure of the durum wheat landraces, with three distinct clusters that corresponded to subsp. durum, turgidum and dicoccon being identified. The population structure of bread wheat landraces was mainly biased by geographic origin. CONCLUSIONS: The results showed broader genetic diversity in the landraces compared to a reference set that included commercial varieties, and higher divergence between the landraces and the reference set in durum wheat than in bread wheat. The analyses revealed genomic regions whose patterns of variation were markedly different in the landraces and reference varieties, indicating loci that have been under selection during crop improvement, which could help to target breeding efforts. The results obtained from this work will provide a basis for future genome-wide association studies.


Subject(s)
Genome, Plant/genetics , Polymorphism, Single Nucleotide/genetics , Triticum/genetics , Alleles , Chromosome Mapping/methods , Genome-Wide Association Study/methods , Genomics/methods , Genotype , Linkage Disequilibrium/genetics , Plant Breeding/methods , Sequence Analysis, DNA/methods
13.
J Med Internet Res ; 21(10): e14360, 2019 10 29.
Article in English | MEDLINE | ID: mdl-31663861

ABSTRACT

The evidence that quality of life is a positive variable for the survival of cancer patients has prompted the interest of the health and pharmaceutical industry in considering that variable as a final clinical outcome. Sustained improvements in cancer care in recent years have resulted in increased numbers of people living with and beyond cancer, with increased attention being placed on improving quality of life for those individuals. Connected Health provides the foundations for the transformation of cancer care into a patient-centric model, focused on providing fully connected, personalized support and therapy for the unique needs of each patient. Connected Health creates an opportunity to overcome barriers to health care support among patients diagnosed with chronic conditions. This paper provides an overview of important areas for the foundations of the creation of a new Connected Health paradigm in cancer care. Here we discuss the capabilities of mobile and wearable technologies; we also discuss pervasive and persuasive strategies and device systems to provide multidisciplinary and inclusive approaches for cancer patients for mental well-being, physical activity promotion, and rehabilitation. Several examples already show that there is enthusiasm in strengthening the possibilities offered by Connected Health in persuasive and pervasive technology in cancer care. Developments harnessing the Internet of Things, personalization, patient-centered design, and artificial intelligence help to monitor and assess the health status of cancer patients. Furthermore, this paper analyses the data infrastructure ecosystem for Connected Health and its semantic interoperability with the Connected Health economy ecosystem and its associated barriers. Interoperability is essential when developing Connected Health solutions that integrate with health systems and electronic health records. Given the exponential business growth of the Connected Health economy, there is an urgent need to develop mHealth (mobile health) exponentially, making it both an attractive and challenging market. In conclusion, there is a need for user-centered and multidisciplinary standards of practice to the design, development, evaluation, and implementation of Connected Health interventions in cancer care to ensure their acceptability, practicality, feasibility, effectiveness, affordability, safety, and equity.


Subject(s)
Artificial Intelligence/standards , Machine Learning/standards , Neoplasms/psychology , Quality of Life/psychology , Telemedicine/methods , Humans , Social Support , Wearable Electronic Devices
14.
Int J Mol Sci ; 20(20)2019 Oct 17.
Article in English | MEDLINE | ID: mdl-31627455

ABSTRACT

Solute binding proteins (SBPs) form a heterogeneous protein family that is found in all kingdoms of life. In bacteria, the ligand-loaded forms bind to transmembrane transporters providing the substrate. We present here the SBP repertoire of Pseudomonas aeruginosa PAO1 that is composed of 98 proteins. Bioinformatic predictions indicate that many of these proteins have a redundant ligand profile such as 27 SBPs for proteinogenic amino acids, 13 proteins for spermidine/putrescine, or 9 proteins for quaternary amines. To assess the precision of these bioinformatic predictions, we have purified 17 SBPs that were subsequently submitted to high-throughput ligand screening approaches followed by isothermal titration calorimetry studies, resulting in the identification of ligands for 15 of them. Experimentation revealed that PA0222 was specific for γ-aminobutyrate (GABA), DppA2 for tripeptides, DppA3 for dipeptides, CysP for thiosulphate, OpuCC for betaine, and AotJ for arginine. Furthermore, RbsB bound D-ribose and D-allose, ModA bound molybdate, tungstate, and chromate, whereas AatJ recognized aspartate and glutamate. The majority of experimentally identified ligands were found to be chemoattractants. Data show that the ligand class recognized by SPBs can be predicted with confidence using bioinformatic methods, but experimental work is necessary to identify the precise ligand profile.


Subject(s)
Bacterial Proteins/chemistry , Pseudomonas aeruginosa/chemistry , Calorimetry , Chemotaxis , Computational Biology , Ligands , Pseudomonas aeruginosa/metabolism , Signal Transduction
15.
Hum Mutat ; 40(7): 975-982, 2019 07.
Article in English | MEDLINE | ID: mdl-30908763

ABSTRACT

D-2-hydroxyglutaric aciduria Type I (D-2-HGA Type I), a neurometabolic disorder with a broad clinical spectrum, is caused by recessive variants in the D2HGDH gene encoding D-2-hydroxyglutarate dehydrogenase (D-2-HGDH). We and others detected 42 potentially pathogenic variants in D2HGDH of which 31 were missense. We developed functional studies to investigate the effect of missense variants on D-2-HGDH catalytic activity. Site-directed mutagenesis was used to introduce 31 missense variants in the pCMV5-D2HGDH expression vector. The wild type and missense variants were overexpressed in HEK293 cells. D-2-HGDH enzyme activity was evaluated based on the conversion of [2 H4 ]D-2-HG to [2 H4 ]2-ketoglutarate, which was subsequently converted into [2 H4 ]L-glutamate and the latter quantified by LC-MS/MS. Eighteen variants resulted in almost complete ablation of D-2-HGDH activity and thus, should be considered pathogenic. The remaining 13 variants manifested residual activities ranging between 17% and 94% of control enzymatic activity. Our functional assay evaluating the effect of novel D2HGDH variants will be beneficial for the classification of missense variants and determination of pathogenicity.


Subject(s)
Alcohol Oxidoreductases/genetics , Alcohol Oxidoreductases/metabolism , Brain Diseases, Metabolic, Inborn/genetics , Mutation, Missense , Brain Diseases, Metabolic, Inborn/metabolism , Chromatography, Liquid , HEK293 Cells , Humans , Mutagenesis, Site-Directed , Tandem Mass Spectrometry , Urogenital Abnormalities
16.
Support Care Cancer ; 27(10): 3823-3831, 2019 Oct.
Article in English | MEDLINE | ID: mdl-30734089

ABSTRACT

PURPOSE: Neuromuscular electrical stimulation (NMES) may be a pragmatic short-term alternative to voluntary exercise to augment cancer rehabilitation. However, previous attempts to use NMES as an exercise modality in this cohort have been unsuccessful, largely due to the use of NMES protocols that were developed for other rehabilitation contexts. We assessed the effects of a personalised and progressive NMES exercise intervention, designed with early-stage cancer rehabilitation in mind, on exercise capacity, lower body functional strength and quality of life in (QoL) in patients who are currently undergoing or have recently completed treatment for cancer. METHODS: Ten adult patients were recruited. A personalised and progressive NMES exercise intervention was implemented in each case over a 4-8-week period. The 30-s sit-to-stand test (STS), 6-min walk test (6MWT) and EORTC QLQ C-30 were performed pre- and post-intervention. Patients completed semi-structured interviews post-intervention to explore their experiences and views on the intervention and its impact on their daily lives. RESULTS: Six of the 10 recruited patients completed the intervention and completed pre-and post-assessments. Four of 6 patients improved STS, 5 of 6 patients improved 6MWT and 4 of 6 patients improved Global QoL. Perceived benefits included improved muscle strength and more confidence when walking. CONCLUSION: A personalised and progressive NMES exercise intervention appears safe and may improve functional capacity and QoL in adults who are undergoing or have recently completed treatment for cancer. Replication of these results in a controlled prospective study is warranted prior to clinical implementation.


Subject(s)
Cancer Survivors/statistics & numerical data , Electric Stimulation Therapy/methods , Electric Stimulation/methods , Exercise/physiology , Quadriceps Muscle/physiology , Adult , Aged , Female , Humans , Male , Muscle Strength/physiology , Neoplasms/physiopathology , Neoplasms/rehabilitation , Prospective Studies , Quality of Life , Research Design , Walking/physiology
17.
Int J Mol Sci ; 19(12)2018 Nov 26.
Article in English | MEDLINE | ID: mdl-30486299

ABSTRACT

Bacteria possess a large number of signal transduction systems that sense and respond to different environmental cues. Most frequently these are transcriptional regulators, two-component systems and chemosensory pathways. A major bottleneck in the field of signal transduction is the lack of information on signal molecules that modulate the activity of the large majority of these systems. We review here the progress made in the functional annotation of sensor proteins using high-throughput ligand screening approaches of purified sensor proteins or individual ligand binding domains. In these assays, the alteration in protein thermal stability following ligand binding is monitored using Differential Scanning Fluorimetry. We illustrate on several examples how the identification of the sensor protein ligand has facilitated the elucidation of the molecular mechanism of the regulatory process. We will also discuss the use of virtual ligand screening approaches to identify sensor protein ligands. Both approaches have been successfully applied to functionally annotate a significant number of bacterial sensor proteins but can also be used to study proteins from other kingdoms. The major challenge consists in the study of sensor proteins that do not recognize signal molecules directly, but that are activated by signal molecule-loaded binding proteins.


Subject(s)
Bacteria/metabolism , Molecular Sequence Annotation , Signal Transduction , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Ligands , Models, Biological
18.
Environ Microbiol ; 20(12): 4230-4244, 2018 12.
Article in English | MEDLINE | ID: mdl-30051572

ABSTRACT

The interference of plant compounds with bacterial quorum sensing (QS) is a major mechanism through which plants and bacteria communicate. However, little is known about the modes of action and effects on signal integrity during this type of communication. We have recently shown that the plant compound rosmarinic acid (RA) specifically binds to the Pseudomonas aeruginosa RhlR QS receptor. To determine the effect of RA on expression patterns, we carried out global RNA-seq analysis. The results show that RA induces the expression of 128 genes, amongst which many virulence factor genes. RA triggers a broad QS response because 88% of the induced genes are known to be controlled by QS, and because RA stimulated genes were found to be involved in all four QS signalling systems within P. aeruginosa. This finding was confirmed through the analysis of transcriptional fusions transferred to wt and a rhlI/lasI double mutant. RA did not induce gene expression in the rhlI/lasI/rhlR triple mutant indicating that the effects observed are due to the RA-RhlR interaction. Furthermore, RA induced seven sRNAs that were all encoded in regions close to QS and/or RA induced genes. This work significantly enhances our understanding of plant bacteria interaction.


Subject(s)
Cinnamates/pharmacology , Depsides/pharmacology , Gene Expression Regulation, Bacterial/drug effects , Pseudomonas aeruginosa/metabolism , Quorum Sensing/drug effects , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Carrier Proteins/metabolism , Cinnamates/metabolism , Depsides/metabolism , Pseudomonas aeruginosa/drug effects , Quorum Sensing/genetics , Virulence Factors/genetics , Virulence Factors/metabolism , Rosmarinic Acid
19.
Methods Mol Biol ; 1729: 291-301, 2018.
Article in English | MEDLINE | ID: mdl-29429099

ABSTRACT

The majority of bacterial chemoreceptors remain functionally un-annotated. The knowledge of chemoreceptor function, however, is indispensable to understanding the evolution of the chemotaxis system in bacteria with different lifestyles. Significant progress in the annotation of chemoreceptor function has been made using experimental strategies that are based on the individual, genetically engineered ligand binding domain (LBD) of chemoreceptors. There is now evidence that all major classes of LBDs can be produced as individual domains that retain their ligand binding activity. Here, we provide a protocol for the combined use of high-throughput ligand screening using Differential Scanning Fluorimetry followed by Isothermal Titration Calorimetry to identify and characterize ligands that bind to recombinant chemoreceptor LBDs. This approach has been shown to be very efficient for determining the function of novel chemoreceptors.


Subject(s)
Bacterial Proteins/metabolism , Chemotactic Factors/metabolism , High-Throughput Screening Assays/methods , Bacteria/metabolism , Bacterial Proteins/chemistry , Calorimetry, Differential Scanning , Chemotaxis , Ligands , Protein Binding , Signal Transduction
20.
JMIR Res Protoc ; 7(1): e14, 2018 Jan 24.
Article in English | MEDLINE | ID: mdl-29367184

ABSTRACT

BACKGROUND: As cancer survival rates increase, the challenge of ensuring that cancer survivors reclaim their quality of life (QoL) becomes more important. This paper outlines the research element of a research and training program that is designed to do just that. OBJECTIVE: Bridging sectors, disciplines, and geographies, it brings together eight PhD projects and students from across Europe to identify the underlying barriers, test different technology-enabled rehabilitative approaches, propose a model to optimize the patient pathways, and examine the business models that might underpin a sustainable approach to cancer survivor reintegration using technology. METHODS: The program, funded under the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 722012, includes deep disciplinary PhD projects, intersectoral and international secondments, interdisciplinary plenary training schools, and virtual subject-specific education modules. RESULTS: The 8 students have now been recruited and are at the early stages of their projects. CONCLUSIONS: CATCH will provide a comprehensive training and research program by embracing all key elements-technical, social, and economic sciences-required to produce researchers and project outcomes that are capable of meeting existing and future needs in cancer rehabilitation.

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