RESUMO
Cultivated oat (Avena sativa L.) is an allohexaploid (AACCDD, 2n = 6x = 42) thought to have been domesticated more than 3,000 years ago while growing as a weed in wheat, emmer and barley fields in Anatolia1,2. Oat has a low carbon footprint, substantial health benefits and the potential to replace animal-based food products. However, the lack of a fully annotated reference genome has hampered efforts to deconvolute its complex evolutionary history and functional gene dynamics. Here we present a high-quality reference genome of A. sativa and close relatives of its diploid (Avena longiglumis, AA, 2n = 14) and tetraploid (Avena insularis, CCDD, 2n = 4x = 28) progenitors. We reveal the mosaic structure of the oat genome, trace large-scale genomic reorganizations in the polyploidization history of oat and illustrate a breeding barrier associated with the genome architecture of oat. We showcase detailed analyses of gene families implicated in human health and nutrition, which adds to the evidence supporting oat safety in gluten-free diets, and we perform mapping-by-sequencing of an agronomic trait related to water-use efficiency. This resource for the Avena genus will help to leverage knowledge from other cereal genomes, improve understanding of basic oat biology and accelerate genomics-assisted breeding and reanalysis of quantitative trait studies.
Assuntos
Avena , Grão Comestível , Genoma de Planta , Avena/genética , Diploide , Grão Comestível/genética , Genoma de Planta/genética , Mosaicismo , Melhoramento Vegetal , TetraploidiaRESUMO
The crown-of-thorns starfish (COTS, the Acanthaster planci species group) is a highly fecund predator of reef-building corals throughout the Indo-Pacific region. COTS population outbreaks cause substantial loss of coral cover, diminishing the integrity and resilience of reef ecosystems. Here we sequenced genomes of COTS from the Great Barrier Reef, Australia and Okinawa, Japan to identify gene products that underlie species-specific communication and could potentially be used in biocontrol strategies. We focused on water-borne chemical plumes released from aggregating COTS, which make the normally sedentary starfish become highly active. Peptide sequences detected in these plumes by mass spectrometry are encoded in the COTS genome and expressed in external tissues. The exoproteome released by aggregating COTS consists largely of signalling factors and hydrolytic enzymes, and includes an expanded and rapidly evolving set of starfish-specific ependymin-related proteins. These secreted proteins may be detected by members of a large family of olfactory-receptor-like G-protein-coupled receptors that are expressed externally, sometimes in a sex-specific manner. This study provides insights into COTS-specific communication that may guide the generation of peptide mimetics for use on reefs with COTS outbreaks.
Assuntos
Recifes de Corais , Genoma/genética , Controle Biológico de Vetores , Estrelas-do-Mar/genética , Animais , Antozoários/parasitologia , Austrália , Biomimética , Feminino , Oceano Índico , Japão , Masculino , Espectrometria de Massas , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Oceano Pacífico , Proteoma/análise , Proteoma/metabolismo , Fatores Sexuais , Especificidade da Espécie , Estrelas-do-Mar/anatomia & histologia , Estrelas-do-Mar/química , Estrelas-do-Mar/enzimologia , TranscriptomaRESUMO
Meat quality can be affected by stress, exhaustion, feed composition, and other physical and environmental conditions. These stressors can alter the pH in postmortem muscle, leading to high pH and low-quality dark cutting (DC) beef, resulting in considerable economic loss. Moreover, the dark cutting prediction may equally provide a measure for animal welfare since it is directly related to animal stress. There are two needs to advance on-site detection of dark cutters: (1) a clear indication that biomarker (signature compounds) levels in cattle correlate with stress and DC outcome; and (2) measuring these biomarkers rapidly and accurately on-farm or the abattoir, depending on the objectives. This critical review assesses which small molecules and proteins have been identified as potential biomarkers of stress and dark cutting in cattle. We discuss the potential of promising small molecule biomarkers, including catecholamine/cortisol metabolites, lactate, succinate, inosine, glucose, and ß-hydroxybutyrate, and we identify a clear research gap for proteomic biomarker discovery in live cattle. We also explore the potential of chemical-sensing and biosensing technologies, including direct electrochemical detection improved through nanotechnology (e.g., carbon and gold nanostructures), surface-enhanced Raman spectroscopy in combination with chemometrics, and commercial hand-held devices for small molecule detection. No current strategy exists to rapidly detect predictive meat quality biomarkers due to the need to further validate biomarkers and the fact that different biosensor types are needed to optimally detect different molecules. Nonetheless, several biomarker/biosensor combinations reported herein show excellent potential to enable the measurement of DC potential in live cattle.
Assuntos
Técnicas Biossensoriais , Proteômica , Animais , Biomarcadores/análise , Biomarcadores/metabolismo , Bovinos , Concentração de Íons de Hidrogênio , Músculo Esquelético/químicaRESUMO
α-Amylase/trypsin inhibitors (ATIs) may have a role in nonceliac wheat sensitivity (NCWS) and celiac disease (CD), but the ATI content and diversity across a range of wheat cultivars are not well characterized. Discovery proteomics was used to detect ATIs across two wheat cultivars: Chara and Magenta. Comprehensive mapping of detected ATIs with the ATIs from the recently published wheat genome RefSeq v1.0 shows the presence of three major subclasses: monomeric (9%), dimeric (61%), and chloroform-methanol (CM) type (30%). Subsequently, the level of 18 ATI isoforms (63 peptides) grouped into four subtypes was monitored across 15 commercial wheat cultivars and the eight parental lines from a multiparent advanced-generation intercross (MAGIC) population using liquid chromatography-multiple reaction monitoring-mass spectrometry (LC-MRM-MS). The ATI content of wheat cultivars Janz, Sunvale, Diamond Bird, and Longreach Scout was significantly lower than that of other wheat cultivars. The MAGIC parental cultivars Baxter and Xiaoyan 54 contain higher levels (â¼115% relative to the average wheat ATI content), whereas cultivar Pastor contained the lowest levels (â¼87%). Comprehensive sequence analysis, annotation, chromosomal locations, and epitope mapping enabled us to build an LC-MRM-MS method to monitor and quantify the immunostimulatory ATI proteins potentially related to NCWS, autoimmune diseases, and metabolic disorders. This provides an opportunity to select wheat cultivars with significantly lower levels of ATIs.
Assuntos
Amilases , Inibidores da Tripsina , Pão , Inibidores Enzimáticos , Proteínas de Plantas/análise , Tripsina , Inibidores da Tripsina/análise , Inibidores da Tripsina/metabolismoRESUMO
The success of seed germination and the successful establishment of seedlings across diverse environmental conditions depends on seed vigour, which is of both economic and ecologic importance. The smoke-derived exogenous compound karrikins (KARs) and the endogenous plant hormone strigolactone (SL) are two classes of butanolide-containing molecules that follow highly similar signalling pathways to control diverse biological activities in plants. Unravelling the precise mode-of-action of these two classes of molecules in model species has been a key research objective. However, the specific and dynamic expression of biomolecules upon stimulation by these signalling molecules remains largely unknown. Genomic and post-genomic profiling approaches have enabled mining and association studies across the vast genetic diversity and phenotypic plasticity. Here, we review the background of smoke-assisted germination and vigour and the current knowledge of how plants perceive KAR and SL signalling and initiate the crosstalk with the germination-associated hormone pathways. The recent advancement of 'multi-omics' applications are discussed in the context of KAR signalling and with relevance to their adoption for superior agronomic trait development. The remaining challenges and future opportunities for integrating multi-omics datasets associated with their application in KAR-dependent seed germination and abiotic stress tolerance are also discussed.
Assuntos
Perfilação da Expressão Gênica , Germinação/genética , Vigor Híbrido/genética , Desenvolvimento Vegetal/genética , Proteômica , Sementes/genética , Fumaça , Adaptação Biológica , Produtos Agrícolas , Meio Ambiente , Regulação da Expressão Gênica de Plantas , Interação Gene-Ambiente , Reguladores de Crescimento de Plantas/metabolismo , Transdução de SinaisRESUMO
The proteome represents the total set of proteins produced by an organism or a system at a particular time or state, with proteomics being the study of the proteome. The proteome is a dynamic system wherein proteins are interconnected and serve to facilitate cellular processes in a concurrent and coordinated manner. Over the years, various biochemical and biophysical methods have been developed to elucidate the identities, structures and functions of proteins in order to understand their roles in complex biological systems. The success of proteomic approaches hinges on efficient protein extraction and sample preparation; however, these preliminary steps are often considered a bottleneck in proteomic workflows. Every biological sample is unique and complex, and sample processing needs to be tailored to the nature of the protein sample due to its vulnerability towards post-collection degradation and the complexity of its non-protein constituents. Sample pretreatment steps often employ buffers, solvents, salts and detergents that are not always compatible with the downstream analytical tools. This chapter will provide an overview of sample pretreatment techniques commonly used in conjunction with proteomics tools and discuss protein analysis methods. Such methods include the use of antibody-based techniques, separation sciences (e.g. chromatography, SDS-PAGE), detection methods (e.g. mass spectrometry) and structural techniques (e.g. NMR and X-ray crystallography).
Assuntos
Proteoma , Proteômica/métodos , Anticorpos/química , Cromatografia , Cristalografia por Raios X , Eletroforese em Gel de Poliacrilamida , Espectroscopia de Ressonância Magnética , Espectrometria de MassasRESUMO
Coeliac disease (CD) is an autoimmune disorder triggered by the ingestion of gluten that is associated with gastrointestinal issues, including diarrhea, abdominal pain, and malabsorption. Gluten is a general name for a class of cereal storage proteins of wheat, barley, and rye that are notably resistant to gastrointestinal digestion. After ingestion, immunogenic peptides are subsequently recognized by T cells in the gastrointestinal tract. The only treatment for CD is a life-long gluten-free diet. As such, it is critical to detect gluten in diverse food types, including those where one would not expect to find gluten. The utility of liquid chromatography-mass spectrometry (LC-MS) using cereal-specific peptide markers to detect gluten in heavily processed food types was assessed. A range of breakfast products, including breakfast cereals, breakfast bars, milk-based breakfast drinks, powdered drinks, and a savory spread, were tested. No gluten was detected by LC-MS in the food products labeled gluten-free, yet enzyme-linked immunosorbent assay (ELISA) measurement revealed inconsistencies in barley-containing products. In products containing wheat, rye, barley, and oats as labeled ingredients, gluten proteins were readily detected using discovery proteomics. Panels comprising ten cereal-specific peptide markers were analyzed by targeted proteomics, providing evidence that LC-MS could detect and differentiate gluten in complex matrices, including baked goods and milk-based products.
Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Análise de Alimentos , Glutens/isolamento & purificação , Proteômica , Austrália , Avena/química , Desjejum , Cromatografia Líquida , Grão Comestível/química , Glutens/química , Hordeum/química , Humanos , Espectrometria de Massas , Triticum/químicaRESUMO
Within the Phylum Echinodermata, the class Asteroidea, commonly known as starfish and sea stars, encompasses a large number of benthos inhabiting genera and species with various feeding modalities including herbivores, carnivores, omnivores and detritivores. The Asteroidea rely on chemosensation throughout their life histories including hunting prey, avoiding or deterring predators, in the formation of spawning aggregations, synchronizing gamete release and targeting appropriate locations for larval settlement. The identities of many of the chemical stimuli that mediate these physiological and behavioural processes remain unresolved even though evidence indicates they play pivotal roles in the functionality of benthic communities. Aspects of chemosensation, as well as putative chemically-mediated behaviours and the molecular mechanisms of chemoreception, within the Asteroidea are reviewed here, with particular reference to the coral reef pest the Crown-of-Thorns starfish Acanthaster planci species complex, in the context of mitigation of population outbreaks.
Assuntos
Equinodermos/fisiologia , Feromônios/metabolismo , Animais , Carnivoridade , Recifes de Corais , Equinodermos/química , Equinodermos/crescimento & desenvolvimento , Herbivoria , Metamorfose Biológica , Controle de Pragas , Feromônios/análise , Comportamento Predatório , Estrelas-do-Mar/química , Estrelas-do-Mar/crescimento & desenvolvimento , Estrelas-do-Mar/fisiologia , SimbioseRESUMO
The sea cucumber (phylum Echinodermata) body wall is the first line of defense and is well known for its production of secondary metabolites; including vitamins and triterpenoid glycoside saponins that have important ecological functions and potential benefits to human health. The genes involved in the various biosynthetic pathways are unknown. To gain insight into these pathways in an echinoderm, we performed a comparative transcriptome analysis and functional annotation of the body wall and the radial nerve of the sea cucumber Holothuria scabra; to define genes associated with body wall metabolic functioning and secondary metabolite biosynthesis. We show that genes related to signal transduction mechanisms were more highly represented in the H. scabra body wall, including genes encoding enzymes involved in energy production. Eight of the core triterpenoid biosynthesis enzymes were found, however, the identity of the saponin specific biosynthetic pathway enzymes remains unknown. We confirm the body wall release of at least three different triterpenoid saponins using solid phase extraction followed by ultra-high-pressure liquid chromatography-quadrupole time of flight-mass spectrometry. The resource we have established will help to guide future research to explore secondary metabolite biosynthesis in the sea cucumber.
Assuntos
Holothuria/metabolismo , Saponinas/biossíntese , Animais , Cromatografia Líquida/métodos , Regulação da Expressão Gênica/fisiologia , Espectrometria de Massas/métodos , Metaboloma , RNA/genética , RNA/metabolismoRESUMO
Abalone (Haliotis) undergoes a period of reproductive maturation, followed by the synchronous release of gametes, called broadcast spawning. Field and laboratory studies have shown that the tropical species Haliotis asinina undergoes a two-week spawning cycle, thus providing an excellent opportunity to investigate the presence of endogenous spawning-associated peptides. In female H. asinina, we have isolated a peptide (5145 Da) whose relative abundance in hemolymph increases substantially just prior to spawning and is still detected using reverse-phase high-performance liquid chromatography chromatograms up to 1-day post-spawn. We have isolated this peptide from female hemolymph as well as samples prepared from the gravid female gonad, and demonstrated through comparative sequence analysis that it contains features characteristic of Kazal-type proteinase inhibitors (KPIs). Has-KPI is expressed specifically within the gonad of adult females. A recombinant Has-KPI was generated using a yeast expression system. The recombinant Has-KPI does not induce premature spawning of female H. asinina when administered intramuscularly. However it displays homomeric aggregations and interaction with at least one mollusc-type neuropeptide (LRDFVamide), suggesting a role for it in regulating neuropeptide endocrine communication. This research provides new understanding of a peptide that can regulate reproductive processes in female abalone, which has the potential to lead to the development of greater control over abalone spawning. The findings also highlight the need to further explore abalone reproduction to clearly define a role for novel spawning-associated peptide in sexual maturation and spawning. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.
Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Moluscos/crescimento & desenvolvimento , Neuropeptídeos/metabolismo , Ovário/metabolismo , Maturidade Sexual/genética , Inibidor da Tripsina Pancreática de Kazal/metabolismo , Sequência de Aminoácidos , Animais , Clonagem Molecular , Feminino , Hemolinfa/química , Modelos Moleculares , Moluscos/genética , Moluscos/metabolismo , Neuropeptídeos/genética , Ovário/crescimento & desenvolvimento , Pichia/genética , Pichia/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Reprodução/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transdução de Sinais , Inibidor da Tripsina Pancreática de Kazal/química , Inibidor da Tripsina Pancreática de Kazal/genética , Inibidor da Tripsina Pancreática de Kazal/isolamento & purificaçãoRESUMO
An LC-MS-based metabolomics approach was used to characterise the variation in secondary metabolite production due to changes in the salt content of the growth media as well as across different growth periods (incubation times). We used metabolomics as a tool to investigate the production of rifamycins (antibiotics) and other secondary metabolites in the obligate marine actinobacterial species Salinispora arenicola, isolated from Great Barrier Reef (GBR) sponges, at two defined salt concentrations and over three different incubation periods. The results indicated that a 14 day incubation period is optimal for the maximum production of rifamycin B, whereas rifamycin S and W achieve their maximum concentration at 29 days. A "chemical profile" link between the days of incubation and the salt concentration of the growth medium was shown to exist and reliably represents a critical point for selection of growth medium and harvest time.
Assuntos
Antibacterianos/isolamento & purificação , Micromonosporaceae/química , Animais , Cromatografia Líquida , Espectrometria de Massas , Metabolômica , Micromonosporaceae/metabolismo , Poríferos/microbiologia , Rifamicinas/isolamento & purificação , Rifamicinas/metabolismo , Água do Mar/microbiologiaRESUMO
Forty-five strains from two different species (Salinispora arenicola and Salinispora pacifica) were isolated from three different marine sponge species in the Great Barrier Reef region of Australia. We found that two of the strains of Salinispora arenicola (MV0335 and MV0029) produced mevinolin, a fungus-derived cholesterol-lowering agent. Compound structure was determined using an integrated approach: (a) high performance liquid chromatography-quadrupole time-of-flight-mass spectrometric analysis with multimode ionization (electrospray ionization and atmospheric pressure chemical ionization) and fast polarity switching; and (b) database searching and matching of monoisotopic masses, retention times and mass spectra of the precursor and product ions of the compounds of interest and the authentic reference standards thereof.
Assuntos
Lovastatina/química , Lovastatina/metabolismo , Micromonosporaceae/metabolismo , Poríferos/microbiologia , Animais , Anticolesterolemiantes/química , Anticolesterolemiantes/isolamento & purificação , Anticolesterolemiantes/metabolismo , Austrália , Lovastatina/isolamento & purificação , Micromonosporaceae/isolamento & purificação , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Wheat proteins can trigger immunogenic reactions due to their resistance to digestion and immunostimulatory epitopes. Here, we investigated the peptidomic map of partially digested bread samples and the fingerprint of epitope diversity from 16 wheat genotypes grown in two environmental conditions. Flour protein content and composition were characterized; gastric and jejunal peptides were quantified using LC-MS/MS, and genotypes were classified into high or low bread protein digestibility. Differences in flour protein content and peptide composition distinguish high from low digestibility genotypes in both growing environments. No common peptide signature was found between high- and low-digestible genotypes; however, the celiac or allergen epitopes were noted not to be higher in low-digestible genotypes. Overall, this study established a peptidomic and epitope diversity map of digested wheat bread and provided new insights and correlations between weather conditions, genotypes, digestibility and wheat sensitivities such as celiac disease and wheat allergy.
RESUMO
SCOPE: Edible insect proteins are increasingly introduced as an alternative sustainable food source to address the world's need to feed the growing population. Tropomyosin is the main insect allergen; however, additional potential allergens are not well characterized and the impact of extraction procedures on immunological reactivity is unknown. METHODS AND RESULTS: Proteins from different commercial food products derived from cricket (Acheta domesticus) and black soldier fly (BSF) (Hermetia illucens) are extracted using five different extraction buffers. The proteins are analyzed by SDS-PAGE and immunoblotting using allergen-specific antibodies and crustacean allergic patient sera. IgE binding bands are analyzed by mass spectrometry as well as the complete allergen profile of all 30 extracts. Urea-based buffers are most efficient in extracting insect allergens. Shrimp-specific antibody cross-reactivity to tropomyosin from cricket and BSF indicates high sequence and structural similarity between shrimp and insects. Additional unique allergens are identified in both species, including hemocyanin, vitellogenin, HSP20, apolipophorin-III, and chitin-binding protein. CONCLUSIONS: Identifying potential allergenic proteins and their isoforms in cricket and BSF requires specific extraction approaches using urea-based methods. While tropomyosin is the most abundant and immunoreactive allergen, seven unique allergens are identified, highlighting the need for insect species-specific allergen detection in food products.
Assuntos
Alérgenos , Insetos Comestíveis , Gryllidae , Imunoglobulina E , Proteínas de Insetos , Animais , Alérgenos/imunologia , Gryllidae/imunologia , Proteínas de Insetos/imunologia , Imunoglobulina E/imunologia , Imunoglobulina E/sangue , Humanos , Insetos Comestíveis/imunologia , Hipersensibilidade Alimentar/imunologia , Reações Cruzadas , Tropomiosina/imunologia , Dípteros/imunologia , Eletroforese em Gel de PoliacrilamidaRESUMO
Per- and poly-fluoroalkyl substances (PFAS) pose a threat to organisms and ecosystems due to their persistent nature. Ecotoxicology endpoints used in regulatory guidelines may not reflect multiple, low-level but persistent stressors. This study examines the biological effects of PFAS on Eastern short-necked turtles in Queensland, Australia. In this study, blood samples were collected and analysed for PFAS, hormone levels, and functional omics endpoints. High levels of PFAS were found in turtles at the impacted site, with PFOS being the dominant constituent. The PFAS profiles of males and females differed, with males having higher PFAS concentrations. Hormone concentrations differed between impacted and reference sites in male turtles, with elevated testosterone and corticosterone indicative of stress. Further, energy utilisation, nucleotide synthesis, nitrogen metabolism, and amino acid synthesis were altered in both male and female turtles from PFAS-impacted sites. Both sexes show similar metabolic responses to environmental stressors from the PFAS-contaminated site, which may adversely affect their reproductive fitness. Purine metabolism, caffeine metabolism, and ferroptosis pathway changes in turtles can cause gout, cell death, and overall health problems. Further, the study showed that prolonged exposure to elevated PFAS levels in the wild could compromise turtle reproductive fitness by disrupting reproductive steroids and metabolic pathways.
Assuntos
Ácidos Alcanossulfônicos , Poluentes Ambientais , Fluorocarbonos , Tartarugas , Animais , Masculino , Feminino , Ecossistema , Aptidão Genética , Água Doce , Hormônios , Fluorocarbonos/toxicidadeRESUMO
Toad parotoid gland secretion or toad venom has in recent years been increasingly shown to possess potentially beneficial pharmacological effects; this speculation has drawn much interest centred on elucidating the chemical basis of its multimodal effects. For this purpose, we explored the use of a rapid and accurate analysis method for systemic investigation of the parotoid gland chemistry, when extracted from Australian cane toads. Full-scan data of cane toad venom extract was acquired using high-performance liquid chromatography coupled with a hybrid quadrupole-time of flight mass spectrometry system (HPLC/MS-Q-TOF), with multiple ionization sources (ESI and APCI) in positive and negative mixed modes. By measuring the exact mass differences between the theoretical and measured mass of each assumed compound, we confirmed the presence of 12 key constituents. The present results demonstrate that the use of HPLC/MS-Q-TOF with multiple ionization sources delivers exemplary selectivity and sensitivity, allowing for the rapid and accurate identification of constituents within cane toad venom. This paves the way for this technique to be used in future routine screening of components within the genus Bufo and for key analytes too, then reliably assessed for any purported beneficial (clinic) properties.
Assuntos
Venenos de Anfíbios/química , Bufo marinus , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Austrália , Bufanolídeos/química , Bufanolídeos/isolamento & purificação , Espécies Introduzidas , Glândula Parótida/metabolismoRESUMO
Complex legacy contamination from human use is a major issue for estuaries globally. In particular, contamination of water and sediments with bioavailable metals/metalloids, in addition to other industrial contaminants, such as hydrocarbons. Yet, understanding of complex toxicity and local adaptation in field exposed, non-model, invertebrate communities is limited. Herein, we apply multi-omics (metabolomics, lipidomics, proteomics) coupled to traditional sediment quality analyses, to better characterise molecular and cellular responses necessary for application to monitoring, as an eco-surveillance tool. Using these approaches, we characterise functional phenotypes of a sediment associated invertebrate (sipunculid), from an estuary exposed to complex legacy contamination (metals: Zn, Hg, Cd, Pb, Cu, As; and polycyclic aromatic hydrocarbons, PAHs). We sampled individuals at a range of exposure sites, highly (NTB5), moderately (NTB13), and lesser-influenced reference sites. Size differences were observed in sampled individuals between sites, with smaller individuals collected from NTB13. Analysis of environmental variables that correlated with change in the metabolite data revealed that the metabolism of smaller individuals at medium exposure NTB13 was highly differentiated by sediment concentrations of Hg, despite higher concentrations at more exposed NTB5. Functional phenotypes of these smaller individuals were characterised by sulphur and aromatic amino acid metabolism, increases in oxidised intermediates, upregulation of protein responses to oxidative stress, and melanin synthesis, and saturation of membrane and storage of lipids; in addition to the metabolism of naphthalene (PAH). Such widespread change was not observed in the metabolite and lipid profiles of larger individuals at high exposure NTB5, suggesting possible differences in effects between sites may also be associated with size (developmental stage, or age) and/or PAH exposure. This study serves to further understanding of differing modes of toxicity and local adaptation to multiple contaminants, and drivers of functional change in a complex estuary environment.
Assuntos
Mercúrio , Metais Pesados , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Animais , Humanos , Sedimentos Geológicos/química , Monitoramento Ambiental , Multiômica , Invertebrados/metabolismo , Metais/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Mercúrio/análise , Poluentes Químicos da Água/análise , Estuários , Metais Pesados/análiseRESUMO
Gluten content labels inform food choice and people practicing a gluten-free diet rely upon them to avoid illness. The regulations differ between jurisdictions, especially concerning fermented foodstuffs such as beer. Gluten abundance is typically measured using ELISAs, which have come into question when testing fermented or hydrolysed foodstuffs such as beer. Mass spectrometry can be used to directly identify gluten peptides and reveal false negatives recorded by ELISA. In this survey of gluten in control and gluten-free beers, gluten protein fragments that contain known immunogenic epitopes were detected using liquid chromatography-mass spectrometry in multiple beers that claim to be gluten-free and have sufficiently low gluten content, as measured by ELISA, to qualify as being gluten-free in some jurisdictions. In fact, several purportedly gluten-free beers showed equivalent or higher hordein content than some of the untreated, control beers. The shortcomings of ELISAs for beer gluten testing are summarised, the mismatch between ELISA and mass spectrometry results are explored, and the suitability of existing regulations as they pertain to the gluten content in fermented foods in different jurisdictions are discussed.
RESUMO
Microalgae offer an opportunity to act as a sustainable source of dietary protein. This study aimed to evaluate the impact of different protein extraction methods on the nutritional and physicochemical properties of Nannochloropsis oculata. Food-grade protein extracts were obtained by hypotonic osmotic shock using milli-Q water. Food grade (FG) and non-food grade (NFG) extraction buffers were compared along with three cell disruption methods including bead beating, probe sonication and a combination of both methods for protein extraction. Mass spectrometry was used for protein and putative allergen identification in FG extracts. Bead beating led to a slightly higher number of identifiable proteins in FG extracts compared to control condition. Putative allergenic proteins were identified in FG extracts of N. oculata using different in-silico methods. These findings support the need to further evaluate the potential allergenic proteins in microalgae including N. oculata such as immunoglobulin E (IgE) binding tests.
Assuntos
Microalgas , Estramenópilas , Alérgenos/química , Alimentos , Estramenópilas/química , Microalgas/químicaRESUMO
Peracetic acid (PAA) applied to whole poultry carcasses can reduce the number of Campylobacter, a leading cause of human gastroenteritis. However, previous modelling experiments indicated that Campylobacter survived in greater numbers when pre-treated with a thermal stress equivalent to poultry processing scalding prior to chilling with PAA than when subject to chilling with PAA only. To better understand how Campylobacter responds to PAA, proteomes of C. jejuni poultry strain 2704 were measured after exposure to PAA (60 ppm, pH 4.0) for 45 min under laboratory ambient conditions (approximately 23 °C) to establish a foundational map of survival mechanism before combining with other stresses. Analysis of 580 quantified proteins did not indicate a triggered "peroxide shock" response, nor were common heat shock responses detected. Thioredoxin, iron homeostatic, peroxiredoxins and cytochrome c peroxidases became more abundant suggesting that PAA disturbed cytoplasmic redox homeostasis resulting in antioxidant activation and increased prioritisation of iron homeostasis. The PAA treatment led to responses that included an increased priority for oxidative phosphorylation and a simultaneous decrease in central metabolism associated protein abundances. Lon protease was induced suggesting it has a role in maintaining homeostasis during non-thermal stress. Proteins in flagella and chemotaxis became more abundant though whether PAA has a chemorepellent effect requires further investigation. Overall, the proteome data suggests there was a rapid cellular response to applied PAA stress in the first 15 min with the adaptation to the stress completing between 30 and 45 min. The findings will help guide PAA implementation in commercial poultry processing in terms of processing location and length of application.