Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 58
Filtrar
Mais filtros

Bases de dados
Tipo de documento
Intervalo de ano de publicação
1.
Microbiology (Reading) ; 168(3)2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35333152

RESUMO

The fungal pathogen Aspergillus fumigatus is frequently cultured from the sputum of cystic fibrosis (CF) patients along with the bacterium Pseudomonas aeruginosa. A. fumigatus secretes a range of secondary metabolites, and one of these, gliotoxin, has inhibitory effects on the host immune response. The effect of P. aeruginosa culture filtrate (CuF) on fungal growth and gliotoxin production was investigated. Exposure of A. fumigatus hyphae to P. aeruginosa cells induced increased production of gliotoxin and a decrease in fungal growth. In contrast, exposure of A. fumigatus hyphae to P. aeruginosa CuF led to increased growth and decreased gliotoxin production. Quantitative proteomic analysis was used to characterize the proteomic response of A. fumigatus upon exposure to P. aeruginosa CuF. Changes in the profile of proteins involved in secondary metabolite biosynthesis (e.g. gliotoxin, fumagillin, pseurotin A), and changes to the abundance of proteins involved in oxidative stress (e.g. formate dehydrogenase) and detoxification (e.g. thioredoxin reductase) were observed, indicating that the bacterial secretome had a profound effect on the fungal proteome. Alterations in the abundance of proteins involved in detoxification and oxidative stress highlight the ability of A. fumigatus to differentially regulate protein synthesis in response to environmental stresses imposed by competitors such as P. aeruginosa. Such responses may ultimately have serious detrimental effects on the host.


Assuntos
Aspergillus fumigatus , Pseudomonas aeruginosa , Humanos , Proteoma/metabolismo , Proteômica , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Secretoma
2.
Parasitology ; : 1-14, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36328953

RESUMO

Temperature is one of the most important factors affecting soil organisms, including the infective stages of parasites and entomopathogenic nematodes, which are important biological control agents. We investigated the response of 2 species of entomopathogenic nematodes to different storage regimes: cold (9°C), culture temperature (20°C) and temperature swapped from 9 to 20°C. For Steinernema carpocapsae, cold storage had profound effects on chemotaxis, stress tolerance and protein expression that were retained in temperature-swapped individuals. These effects included reversal of chemotactic response for 3 (prenol, methyl salicylate and hexanol) of the 4 chemicals tested, and enhanced tolerance to freezing (−10°C) and desiccation (75% RH). Label-free quantitative proteomics showed that cold storage induced widespread changes in S. carpocapsae, including an increase in heat-shock proteins and late embryogenesis abundant proteins. For Heterorhabditis megidis, cold storage had a less dramatic effect on chemotaxis (as previously shown for proteomic expression) and changes were not maintained on return to 20°C. Thus, cold temperature exposure has significant effects on entomopathogenic nematodes, but the nature of the change depends on the species. Steinernema carpocapsae, in particular, displays significant plasticity, and its behaviour and stress tolerance may be manipulated by brief exposure to low temperatures, with implications for its use as a biological control agent.

3.
Mol Cell Proteomics ; 19(8): 1346-1359, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32447284

RESUMO

Individuals with cystic fibrosis are susceptible to co-infection by Aspergillus fumigatus and Pseudomonas aeruginosa Despite the persistence of A. fumigatus in the cystic fibrosis lung P. aeruginosa eventually predominates as the primary pathogen. Several factors are likely to facilitate P. aeruginosa colonization in the airways, including alterations to the microbial environment. The cystic fibrosis airways are hypoxic, nitrate-rich environments, and the sputum has higher amino acid concentrations than normal. In this study, significant growth proliferation was observed in P. aeruginosa when the bacteria were exposed to A. fumigatus culture filtrates (CuF) containing a high nitrate content. Proteomic analysis of the A. fumigatus CuF identified a significant number of environment-altering proteases and peptidases. The molecular mechanisms promoting bacterial growth were investigated using label-free quantitative (LFQ) proteomics to compare the proteome of P. aeruginosa grown in the A. fumigatus CuF and in CuF produced by a P. aeruginosa-A. fumigatus co-culture, to that cultured in P. aeruginosa CuF. LFQ proteomics revealed distinct changes in the proteome of P. aeruginosa when cultured in the different CuFs, including increases in the levels of proteins involved in denitrification, stress response, replication, amino acid metabolism and efflux pumps, and a down-regulation of pathways involving ABC transporters. These findings offer novel insights into the complex dynamics that exist between P. aeruginosa and A. fumigatus Understanding the molecular strategies that enable P. aeruginosa to predominate in an environment where A. fumigatus exists is important in the context of therapeutic development to target this pathogen.


Assuntos
Aspergillus fumigatus/metabolismo , Coinfecção/microbiologia , Proteoma/metabolismo , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/metabolismo , Aminoácidos/metabolismo , Técnicas de Cocultura , Análise de Componente Principal , Hidrolisados de Proteína/metabolismo , Proteômica
4.
Biochemistry ; 59(4): 563-581, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-31851823

RESUMO

Development of small molecule inhibitors of protein-protein interactions (PPIs) is hampered by our poor understanding of the druggability of PPI target sites. Here, we describe the combined application of alanine-scanning mutagenesis, fragment screening, and FTMap computational hot spot mapping to evaluate the energetics and druggability of the highly charged PPI interface between Kelch-like ECH-associated protein 1 (KEAP1) and nuclear factor erythroid 2 like 2 (Nrf2), an important drug target. FTMap identifies four binding energy hot spots at the active site. Only two of these are exploited by Nrf2, which alanine scanning of both proteins shows to bind primarily through E79 and E82 interacting with KEAP1 residues S363, R380, R415, R483, and S508. We identify fragment hits and obtain X-ray complex structures for three fragments via crystal soaking using a new crystal form of KEAP1. Combining these results provides a comprehensive and quantitative picture of the origins of binding energy at the interface. Our findings additionally reveal non-native interactions that might be exploited in the design of uncharged synthetic ligands to occupy the same site on KEAP1 that has evolved to bind the highly charged DEETGE binding loop of Nrf2. These include π-stacking with KEAP1 Y525 and interactions at an FTMap-identified hot spot deep in the binding site. Finally, we discuss how the complementary information provided by alanine-scanning mutagenesis, fragment screening, and computational hot spot mapping can be integrated to more comprehensively evaluate PPI druggability.


Assuntos
Proteína 1 Associada a ECH Semelhante a Kelch/química , Fator 2 Relacionado a NF-E2/química , Sítios de Ligação/efeitos dos fármacos , Sítios de Ligação/fisiologia , Descoberta de Drogas , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Ligantes , Fator 2 Relacionado a NF-E2/metabolismo , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Domínios Proteicos/efeitos dos fármacos , Domínios Proteicos/fisiologia , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia
5.
J Proteome Res ; 19(1): 279-291, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31693381

RESUMO

Aspergillus fumigatus and Pseudomonas aeruginosa are the most prevalent fungal and bacterial pathogens associated with cystic-fibrosis-related infections, respectively. P. aeruginosa eventually predominates as the primary pathogen, though it is unknown why this is the case. Label-free quantitative proteomics was employed to investigate the cellular response of the alveolar epithelial cell line, A549, to coexposure of A. fumigatus and P. aeruginosa. These studies revealed a significant increase in the rate of P. aeruginosa proliferation where A. fumigatus was present. Shotgun proteomics performed on A549 cells exposed to either A. fumigatus or P. aeruginosa or to A. fumigatus and P. aeruginosa sequentially revealed distinct changes to the host cell proteome in response to either or both pathogens. While key signatures of infection were retained among all pathogen-exposed groups, including changes in mitochondrial activity and energy output, the relative abundance of proteins associated with endocytosis, phagosomes, and lysosomes was decreased in sequentially exposed cells compared to cells exposed to either pathogen. Our findings indicate that A. fumigatus renders A549 cells unable to internalize bacteria, thus providing an environment in which P. aeruginosa can proliferate. This research provides novel insights into the whole-cell proteomic response of A549 cells to A. fumigatus and P. aeruginosa and highlights distinct differences in the proteome following sequential exposure to both pathogens, which may explain why P. aeruginosa can predominate.


Assuntos
Aspergilose/metabolismo , Proteoma/análise , Infecções por Pseudomonas/metabolismo , Células A549 , Aspergillus fumigatus/patogenicidade , Análise por Conglomerados , Coinfecção , Fibrose Cística/microbiologia , Humanos , Proteínas Mitocondriais/metabolismo , Proteoma/genética , Proteoma/metabolismo , Proteômica/métodos , Pseudomonas aeruginosa/patogenicidade
6.
BMC Genomics ; 20(1): 959, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823732

RESUMO

BACKGROUND: Understanding the mechanisms by which organisms adapt to unfavourable conditions is a fundamental question in ecology and evolutionary biology. One such mechanism is diapause, a period of dormancy typically found in nematodes, fish, crustaceans and insects. This state is a key life-history event characterised by arrested development, suppressed metabolism and increased stress tolerance and allows an organism to avoid prolonged periods of harsh and inhospitable environmental conditions. For some species, diapause is preceded by mating which can have a profound effect on female behaviour, physiology and key biological processes, including immunity. However, our understanding of how mating impacts long-term immunity and whether these effects persist throughout diapause is currently limited. To address this, we explored molecular changes in the haemolymph of the ecologically important pollinator, the buff-tailed bumblebee Bombus terrestris. B. terrestris queens mate prior to entering diapause, a non-feeding period of arrested development that can last 6-9 months. Using mass-spectrometry-based proteomics, we quantified changes in the pre-diapause queen haemolymph after mating, as well as the subsequent protein expression of mated queens during and post-diapause. RESULTS: Our analysis identified distinct proteome profiles associated with diapause preparation, maintenance and termination. More specifically, mating pre-diapause was followed by an increase in the abundance of antimicrobial peptides, key effectors of the immune system. Furthermore, we identified the elevated abundance of these proteins to be maintained throughout diapause. This finding was in contrast to the general reduction observed in immune proteins during diapause suggestive of selective immune priming and expression during diapause. Diapause also affected the expression of proteins involved in cuticular maintenance, olfaction, as well as proteins of unknown function, which may have roles in diapause regulation. CONCLUSIONS: Our results provide clear molecular evidence for the consequences and benefits of mating at the immune level as it precedes the selective increased abundance of antimicrobial peptides that are sustained throughout diapause. In addition, our results provide novel insights into the molecular mechanisms by which bumblebees prepare for, survive, and recover from diapause, insights that may have implications for our general understanding of these processes in other insect groups.


Assuntos
Abelhas/fisiologia , Diapausa de Inseto/fisiologia , Animais , Abelhas/crescimento & desenvolvimento , Abelhas/imunologia , Abelhas/metabolismo , Feminino , Hemolinfa/metabolismo , Imunidade Inata , Proteínas de Insetos/metabolismo , Fenótipo , Proteômica , Reprodução
7.
J Am Chem Soc ; 139(21): 7264-7272, 2017 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-28475321

RESUMO

Botulinum neurotoxin serotype A (BoNT/A) causes a debilitating and potentially fatal illness known as botulism. The toxin is also a bioterrorism threat, yet no pharmacological antagonist to counteract its effects has reached clinical approval. Existing strategies to negate BoNT/A intoxication have looked to antibodies, peptides, or organic small molecules as potential therapeutics. In this work, a departure from the traditional drug discovery mindset was pursued, in which the enzyme's susceptibility to metal ions was exploited. A screen of a series of metal salts showed marked inhibitory activity of group 11 and 12 metals against the BoNT/A light chain (LC) protease. Enzyme kinetics revealed that copper (I) and (II) cations displayed noncompetitive inhibition of the LC (Ki ≈ 1 µM), while mercury (II) cations were 10-fold more potent. Crystallographic and mutagenesis studies elucidated a key binding interaction between Cys165 on BoNT/A LC and the inhibitory metals. As potential copper prodrugs, ligand-copper complexes were examined in a cell-based model and were found to prevent BoNT/A cleavage of the endogenous protein substrate, SNAP-25, even at low µM concentrations of complexes. Further investigation of the complexes suggested a bioreductive mechanism causing intracellular release of copper, which directly inhibited the BoNT/A protease. In vivo experiments demonstrated that copper (II) dithiocarbamate and bis(thiosemicarbazone) complexes could delay BoNT/A-mediated lethality in a rodent model, indicating their potential for treating the harmful effects of BoNT/A intoxication. Our studies illustrate that metals can be therapeutically viable enzyme inhibitors; moreover, enzymes that share homology with BoNT LCs may be similarly targeted with metals.


Assuntos
Toxinas Botulínicas Tipo A/antagonistas & inibidores , Complexos de Coordenação/farmacologia , Cobre/farmacologia , Inibidores de Proteases/farmacologia , Tiocarbamatos/farmacologia , Tiossemicarbazonas/farmacologia , Animais , Toxinas Botulínicas Tipo A/metabolismo , Toxinas Botulínicas Tipo A/toxicidade , Complexos de Coordenação/química , Cobre/química , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Cinética , Camundongos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Inibidores de Proteases/química , Relação Estrutura-Atividade , Tiocarbamatos/química , Tiossemicarbazonas/química
8.
Ophthalmology ; 124(8): 1126-1135, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28438415

RESUMO

OBJECTIVE: We conducted a retrospective comparative-effectiveness study of best-corrected visual acuity (BCVA) and refractive error (RE) after immediate sequential (ISBCS) and delayed sequential (DSBCS) bilateral cataract surgery. We tested 2 hypotheses: (1) among DSBCS patients, second-eye outcomes were no different than first-eye outcomes; (2) averaged between each patient's 2 eyes, outcomes did not differ between ISBCS and DSBCS patients. DESIGN: Retrospective comparative-effectiveness study. PARTICIPANTS: Kaiser Permanente Northern California members who underwent noncomplex bilateral cataract surgery from January 1, 2013, through June 30, 2015. METHODS: We performed an intention-to-treat analysis comparing ISBCS to DSBCS using conditional logistic regression analysis, accounting for surgeon and patient-level factors. MAIN OUTCOME MEASURES: BCVA, RE. RESULTS: The analysis of visual outcomes included both eyes of 13 711 DSBCS and 3561 ISBCS patients. Because of the large sample size, some statistical differences lacked clinical significance. Ocular comorbidities were slightly more prevalent in DSBCS patients. Postoperative BCVA was 20/20 or better in 48% of DSBCS first eyes, 49% of DSBCS second eyes, 53% of ISBCS right eyes, and 51% of ISBCS left eyes. The within-person difference in postoperative BCVA averaged zero (0.00) between the first and second DSBCS eyes, and between the ISBCS right and left eyes. After adjustment, average postoperative BCVA was better in ISBCS patients, although the difference was not statistically significant (compared with 20/20 or better: odds ratio for worse than 20/20 was 0.91, 95% confidence interval 0.83-1.01). Emmetropia (spherical equivalent -0.5 to 0 diopter) was achieved in 61% of first DSBCS eyes, 61% of second DSBCS eyes, 63% of ISBCS right eyes, and 63% of ISBCS left eyes. After adjustment, average postoperative RE was no different in ISBCS compared with DSBCS patients (compared with emmetropia: odds ratio for ametropia was 1.02, confidence interval 0.92-1.12). We confirmed 1 case of postoperative endophthalmitis in 10 494 ISBCS eyes (1.0 per 10 000 eyes) and 2 cases in 38 736 DSBCS eyes (0.5 per 10 000 eyes) (P = 0.6), and no patient had bilateral endophthalmitis. CONCLUSIONS: Compared with DSBCS, we found no evidence that ISBCS was associated with worse postoperative BCVA or RE, or with an increased complication risk.


Assuntos
Implante de Lente Intraocular , Facoemulsificação/métodos , Acuidade Visual/fisiologia , Idoso , Idoso de 80 Anos ou mais , Biometria , California/epidemiologia , Feminino , Humanos , Masculino , Programas de Assistência Gerenciada/estatística & dados numéricos , Período Pós-Operatório , Pseudofacia/fisiopatologia , Erros de Refração/fisiopatologia , Estudos Retrospectivos , Resultado do Tratamento
9.
PLoS One ; 19(5): e0304429, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38781164

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0057413.].

10.
Heliyon ; 9(9): e19416, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37674820

RESUMO

To establish meaningful and sustainable policy directives for sustainable pesticide use in agriculture, baseline knowledge of pesticide levels in soils is required. To address this, five pesticides and one metabolite widely used in Irish agriculture and five neonicotinoid compounds pesticides were screened from soils from 25 fields. These sites represented a diversity of soil and land use types. Prothioconazole was detected in 16 of the 18 sites where it had been recently applied, with the highest maximum concentration quantified of 46 µg/kg. However, a week after application only four fields had prothioconazole concentrations above the limit of quantification (LOQ). Fluroxypyr was applied in 11 sites but was not detected above LOQ. Glyphosate and AMPA were not detected. Interestingly, neonicotinoids were detected in 96% of all sampling sites, even though they were not reported as recently applied. Excluding neonicotinoids, 60% of sites were found to contain pesticide residues of compounds that were not previously applied, with boscalid and azoxystrobin detected in 15 of the 25 sites sampled. The total number of pesticides detected in Irish soils were significantly negatively correlated with clay fraction, while average pesticide concentrations were significantly positively correlated with log Kow values. 17 fields were found to have total pesticide concentrations in excess of 0.5 µg/kg, even when recently applied pesticides were removed from calculations. Theoretical consideration of quantified pesticides determined that azoxystrobin has high leaching risk, while boscalid, which was detected but not applied, has an accumulation risk. This information provides insight into the current level of pesticide contamination in Irish agricultural soil and contributes to the European-level effort to understand potential impacts of pesticide contamination in soil.

11.
Sci Total Environ ; 864: 161074, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36566850

RESUMO

Glyphosate is one of the most widely used herbicides globally. It acts by inhibiting an enzyme in an aromatic amino acid synthesis pathway specific to plants and microbes, leading to the view that it poses no risk to other organisms. However, there is growing concern that glyphosate is associated with health effects in humans and an ever-increasing body of evidence that suggests potential deleterious effects on other animals including pollinating insects such as bees. Although pesticides have long been considered a factor in the decline of wild bee populations, most research on bees has focussed on demonstrating and understanding the effects of insecticides. To assess whether glyphosate poses a risk to bees, we characterised changes in survival, behaviour, sucrose solution consumption, the digestive tract proteome, and the microbiota in the bumblebee Bombus terrestris after chronic exposure to field relevant doses of technical grade glyphosate or the glyphosate-based formulation, RoundUp Optima+®. Regardless of source, there were changes in response to glyphosate exposure in important cellular and physiological processes in the digestive tract of B. terrestris, with proteins associated with oxidative stress regulation, metabolism, cellular adhesion, the extracellular matrix, and various signalling pathways altered. Interestingly, proteins associated with endocytosis, oxidative phosphorylation, the TCA cycle, and carbohydrate, lipid, and amino acid metabolism were differentially altered depending on whether the exposure source was glyphosate alone or RoundUp Optima+®. In addition, there were alterations to the digestive tract microbiota of bees depending on the glyphosate source No impacts on survival, behaviour, or food consumption were observed. Our research provides insights into the potential mode of action and consequences of glyphosate exposure at the molecular, cellular and organismal level in bumblebees and highlights issues with the current honeybee-centric risk assessment of pesticides and their formulations, where the impact of co-formulants on non-target organisms are generally overlooked.


Assuntos
Herbicidas , Inseticidas , Microbiota , Humanos , Abelhas , Animais , Proteoma , Trato Gastrointestinal , Herbicidas/toxicidade , Glifosato
12.
Genome Biol Evol ; 15(4)2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-37042738

RESUMO

All organisms require an immune system to recognize, differentiate, and defend against pathogens. From an evolutionary perspective, immune systems evolve under strong selective pressures exerted by fast-evolving pathogens. However, the functional diversity of the immune system means that different immune components and their associated genes may evolve under varying forms of selection. Insect pollinators, which provide essential ecosystem services, are an important system in which to understand how selection has shaped immune gene evolution as their populations are experiencing declines with pathogens highlighted as a potential contributing factor. To improve our understanding of the genetic variation found in the immune genes of an essential pollinator, we performed whole-genome resequencing of wild-caught Bombus terrestris males. We first assessed nucleotide diversity and extended haplotype homozygosity for canonical immune genes finding the strongest signatures of positive selection acting on genes involved in pathogen recognition and antiviral defense, possibly driven by growing pathogen spread in wild populations. We also identified immune genes evolving under strong purifying selection, highlighting potential constraints on the bumblebee immune system. Lastly, we highlight the potential loss of function alleles present in the immune genes of wild-caught haploid males, suggesting that such genes are potentially less essential for development and survival and represent redundancy in the gene repertoire of the bumblebee immune system. Collectively, our analysis provides novel insights into the recent evolutionary history of the immune system of a key pollinator, highlighting targets of selection, constraints to adaptation, and potential redundancy.


Assuntos
Adaptação Fisiológica , Ecossistema , Masculino , Abelhas/genética , Animais , Aclimatação , Análise de Sequência de DNA , Seleção Genética
13.
Front Plant Sci ; 14: 1194866, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37593044

RESUMO

Introduction: Despite the critical role of programmed cell death (PCD) in plant development and defense responses, its regulation is not fully understood. It has been proposed that mitochondria may be important in the control of the early stages of plant PCD, but the details of this regulation are currently unknown. Methods: We used Arabidopsis thaliana cell suspension culture, a model system that enables induction and precise monitoring of PCD rates, as well as chemical manipulation of this process to generate a quantitative profile of the alterations in mitochondrial and cytosolic proteomes associated with early stages of plant PCD induced by heat stress. The cells were subjected to PCD-inducing heat levels (10 min, 54°C), with/without the calcium channel inhibitor and PCD blocker LaCl3. The stress treatment was followed by separation of cytosolic and mitochondrial fractions and mass spectrometry-based proteome analysis. Results: Heat stress induced rapid and extensive changes in protein abundance in both fractions, with release of mitochondrial proteins into the cytosol upon PCD induction. In our system, LaCl3 appeared to act downstream of cell death initiation signal, as it did not affect the release of mitochondrial proteins, but instead partially inhibited changes occurring in the cytosolic fraction, including upregulation of proteins with hydrolytic activity. Discussion: We characterized changes in protein abundance and localization associated with the early stages of heat stress-induced PCD. Collectively, the generated data provide new insights into the regulation of cell death and survival decisions in plant cells.

14.
J Glob Antimicrob Resist ; 28: 90-96, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34922055

RESUMO

OBJECTIVES: This study compared the proteomics of Escherichia coli containing the multidrug resistance plasmid pEK499 under antimicrobial stress and with no antimicrobial. METHODS: We utilised mass spectrometry-based proteomics to compare the proteomes of the bacteria and plasmid under antimicrobial stress and no antimicrobial. RESULTS: Our analysis identified statistically significant differentially abundant (SSDA) proteins common to groups exposed to the ß-lactam antimicrobials but not ciprofloxacin, indicating a ß-lactam stress response to exposure from this class of drugs, irrespective of ß-lactam resistance or susceptibility. Data arising from comparisons of the proteomes of ciprofloxacin-treated E. coli and controls detected an increase in the relative abundance of proteins associated with ribosomes, translation, the TCA cycle and several proteins associated with detoxification, and a decrease in the relative abundance of proteins associated with the stress response, including oxidative stress. We identified changes in proteins associated with persister formation in the presence of ciprofloxacin but not the ß-lactams. The plasmid proteome differed across each treatment and did not follow the pattern of antimicrobial-antimicrobial resistance (AMR) protein associations: a relative increase was observed in the amount of CTX-M-15 in the presence of cefotaxime and ciprofloxacin, but not the other ß-lactams, suggesting regulation of CTX-M-15 protein production. CONCLUSION: The proteomic data from this study provided novel insights into the proteins produced from the chromosome and plasmid under different antimicrobial stresses. These data also identified novel proteins not previously associated with AMR or antimicrobial responses in pathogens, which may well represent potential targets of AMR inhibition.


Assuntos
Anti-Infecciosos , Cefotaxima , Ampicilina/farmacologia , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Cefotaxima/farmacologia , Ciprofloxacina/farmacologia , Resistência a Múltiplos Medicamentos , Escherichia coli/genética , Escherichia coli/metabolismo , Imipenem , Plasmídeos/genética , Proteoma , Proteômica , beta-Lactamases/metabolismo , beta-Lactamas
15.
PLoS One ; 17(4): e0266164, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35390034

RESUMO

Entomopathogenic nematodes (EPN) of the genera Steinernema and Heterorhabditis are parasites which kill and reproduce within insects. While both have life cycles centred around their developmentally arrested, nonfeeding and stress tolerant infective juvenile (IJ) stage, they are relatively distantly related. These IJs are promising biocontrol agents, and their shelf life and stress tolerance may be enhanced by storage at low temperatures. The purpose of this study was to investigate how the proteome of the IJs of two distantly related EPN species is affected by storage at 9°C (for up to 9 weeks) and 20°C (for up to 6 weeks), using label-free quantitative proteomics. Overall, more proteins were detected in S. carpocapsae (2422) than in H. megidis (1582). The S. carpocapsae proteome was strongly affected by temperature, while the H. megidis proteome was affected by both time and temperature. The proteins which increased in abundance to the greatest extent in S. carpocapsae IJs after conditioning at 9°C were chaperone proteins, and proteins related to stress. The proteins which increased in abundance the most after storage at 20°C were proteins related to the cytoskeleton, cell signalling, proteases and their inhibitors, which may have roles in infection. The proteins which decreased in abundance to the greatest extent in S. carpocapsae after both 9°C and 20°C storage were those associated with metabolism, stress and the cytoskeleton. After storage at both temperatures, the proteins increased to the greatest extent in H. megidis IJs were those associated with the cytoskeleton, cell signalling and carbon metabolism, and the proteins decreased in abundance to the greatest extent were heat shock and ribosomal proteins, and those associated with metabolism. As the longest-lived stage of the EPN life cycle, IJs may be affected by proteostatic stress, caused by the accumulation of misfolded proteins and toxic aggregates. The substantial increase of chaperone proteins in S. carpocapsae, and to a greater extent at 9°C, and the general decrease in ribosomal and chaperone proteins in H. megidis may represent species-specific proteostasis mechanisms. Similarly, organisms accumulate reactive oxygen species (ROS) over time and both species exhibited a gradual increase in proteins which enhance ROS tolerance, such as catalase. The species-specific responses of the proteome in response to storage temperature, and over time, may reflect the phylogenetic distance and/or different ecological strategies.


Assuntos
Proteoma , Rabditídios , Animais , Filogenia , Espécies Reativas de Oxigênio , Rabditídios/fisiologia , Temperatura
16.
G3 (Bethesda) ; 12(3)2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-34878113

RESUMO

The English grain aphid, Sitobion avenae, is a major agricultural pest of wheat, barley and oats, and one of the principal vectors of barley yellow dwarf virus leading to significant reductions in grain yield, annually. Emerging resistance to and increasing regulation of insecticides has resulted in limited options for their control. Using PacBio HiFi data, we have produced a high-quality draft assembly of the S. avenae genome; generating a primary assembly with a total assembly size of 475.7 Mb, and an alternate assembly with a total assembly size of 430.8 Mb. Our primary assembly was highly contiguous with only 326 contigs and a contig N50 of 15.95 Mb. Assembly completeness was estimated at 97.7% using BUSCO analysis and 31,007 and 29,037 protein-coding genes were predicted from the primary and alternate assemblies, respectively. This assembly, which is to our knowledge the first for an insecticide resistant clonal lineage of English grain aphid, will provide novel insight into the molecular and mechanistic determinants of resistance and will facilitate future research into mechanisms of viral transmission and aphid behavior.


Assuntos
Afídeos , Buchnera , Animais , Afídeos/genética , Buchnera/genética , Genoma , Análise de Sequência de DNA , Triticum/genética
17.
PeerJ ; 10: e13586, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35855900

RESUMO

Besides the benefits of plant protection products (PPPs) for agricultural production, there is an increasing acknowledgement of the associated potential environmental risks. Here, we examine the feasibility of summarizing the extent of PPP usage at the country level, using Ireland as a case study, as well as at the European level. We used the area over which PPPs are applied (basic area) as an example variable that is relevant to initially assess the geographic extent of environmental risk. In Irish agricultural systems, which are primarily grass-based, herbicides fluroxypyr and glyphosate are the most widely applied active substances (ASs) in terms of basic area, followed by the fungicides chlorothalonil and prothioconazole that are closely associated with arable crops. Although all EU countries are subject to Regulation (EC) No 1185/2009, which sets the obligation of PPP usage data reporting at the national level, we only found usable data that met our criteria for Estonia, Germany, Finland, and Spain (4 of 30 countries reviewed). Overall, the most widely applied fungicide and herbicide in terms of basic area were prothioconazole (20%, 7% and 5% of national cultivated areas of Germany, Estonia and Ireland) and glyphosate (11%, 8% and 5% of national cultivated areas of Spain, Estonia and Ireland) respectively, although evaluations using application frequency may result in the observation of different trends. Several recommendations are proposed to tackle current data gaps and deficiencies in accessibility and usability of pesticide usage data across the EU in order to better inform environmental risk assessment and promote evidence-based policymaking.


Assuntos
Fungicidas Industriais , Herbicidas , Magnoliopsida , Praguicidas , Agricultura , Irlanda
18.
Am J Ophthalmol ; 235: 241-248, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34582764

RESUMO

PURPOSE: In bilaterally pseudophakic patients who received immediate or delayed sequential bilateral cataract surgery (ISBCS or DSBCS), we sought to determine patient experience, particularly related to the loss of opportunity to modify the surgical plan for the second eye. DESIGN: Cross-sectional. METHODS: Patients who received ISBCS (n = 1818) and DSBCS (n = 1818) in the Kaiser Permanente Northern California system between 2017 and 2019 who actively used the electronic patient portal were randomly selected and sent a survey link. The survey inquired about reasons for choosing ISBCS or DSBCS, concerns about surgery, and whether the loss of opportunity to modify the surgical plan for the second eye affected the patient's decision to undergo ISBCS. RESULTS: Participation was 18% among patients who received ISBCS and 17% among patients who received DSBCS. Of the patients who received ISBCS, 96% would choose ISBCS again while 80% of patients who received DSBCS would choose DSBCS again (P < .0001). Convenience was the leading reason patients chose ISBCS (65%), whereas surgeon recommendation was the primary reason patients chose DSBCS (68%). Sixteen percent of patients who received ISBCS and 38% of patients who received DSCBS reported that the possibility of modifying the surgical plan to reduce the need for corrective lenses in the second eye was an important consideration (P < .0001). CONCLUSIONS: Compared with patient who chose DSBCS, patients who chose ISBCS were more likely to choose ISBCS again and to recommend ISBCS to a family member or friend. The option to modify the surgical plan for the second eye to reduce need for glasses or contact lenses was not an important consideration for most of either group.


Assuntos
Extração de Catarata , Catarata , Facoemulsificação , Estudos Transversais , Humanos , Implante de Lente Intraocular , Avaliação de Resultados da Assistência ao Paciente , Satisfação do Paciente , Satisfação Pessoal
19.
J Proteome Res ; 10(4): 1505-18, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21226539

RESUMO

The relationship between aphids and their host plants is thought to be functionally analogous to plant-pathogen interactions. Although virulence effector proteins that mediate plant defenses are well-characterized for pathogens such as bacteria, oomycetes, and nematodes, equivalent molecules in aphids and other phloem-feeders are poorly understood. A dual transcriptomic-proteomic approach was adopted to generate a catalog of candidate effector proteins from the salivary glands of the pea aphid, Acyrthosiphon pisum. Of the 1557 transcript supported and 925 mass spectrometry identified proteins, over 300 proteins were identified with secretion signals, including proteins that had previously been identified directly from the secreted saliva. Almost half of the identified proteins have no homologue outside aphids and are of unknown function. Many of the genes encoding the putative effector proteins appear to be evolving at a faster rate than homologues in other insects, and there is strong evidence that genes with multiple copies in the genome are under positive selection. Many of the candidate aphid effector proteins were previously characterized in typical phytopathogenic organisms (e.g., nematodes and fungi) and our results highlight remarkable similarities in the saliva from plant-feeding nematodes and aphids that may indicate the evolution of common solutions to the plant-parasitic lifestyle.


Assuntos
Afídeos/química , Perfilação da Expressão Gênica , Proteínas de Insetos/análise , Proteoma/análise , Proteômica/métodos , Saliva/química , Sequência de Aminoácidos , Animais , Afídeos/metabolismo , Eletroforese em Gel Bidimensional , Etiquetas de Sequências Expressas , Proteínas de Insetos/classificação , Proteínas de Insetos/genética , Espectrometria de Massas/métodos , Dados de Sequência Molecular , Filogenia , Sinais Direcionadores de Proteínas/genética , Alinhamento de Sequência
20.
BMC Genomics ; 12: 623, 2011 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-22185240

RESUMO

BACKGROUND: Understanding polyphenism, the ability of a single genome to express multiple morphologically and behaviourally distinct phenotypes, is an important goal for evolutionary and developmental biology. Polyphenism has been key to the evolution of the Hymenoptera, and particularly the social Hymenoptera where the genome of a single species regulates distinct larval stages, sexual dimorphism and physical castes within the female sex. Transcriptomic analyses of social Hymenoptera will therefore provide unique insights into how changes in gene expression underlie such complexity. Here we describe gene expression in individual specimens of the pre-adult stages, sexes and castes of the key pollinator, the buff-tailed bumblebee Bombus terrestris. RESULTS: cDNA was prepared from mRNA from five life cycle stages (one larva, one pupa, one male, one gyne and two workers) and a total of 1,610,742 expressed sequence tags (ESTs) were generated using Roche 454 technology, substantially increasing the sequence data available for this important species. Overlapping ESTs were assembled into 36,354 B. terrestris putative transcripts, and functionally annotated. A preliminary assessment of differences in gene expression across non-replicated specimens from the pre-adult stages, castes and sexes was performed using R-STAT analysis. Individual samples from the life cycle stages of the bumblebee differed in the expression of a wide array of genes, including genes involved in amino acid storage, metabolism, immunity and olfaction. CONCLUSIONS: Detailed analyses of immune and olfaction gene expression across phenotypes demonstrated how transcriptomic analyses can inform our understanding of processes central to the biology of B. terrestris and the social Hymenoptera in general. For example, examination of immunity-related genes identified high conservation of important immunity pathway components across individual specimens from the life cycle stages while olfactory-related genes exhibited differential expression with a wider repertoire of gene expression within adults, especially sexuals, in comparison to immature stages. As there is an absence of replication across the samples, the results of this study are preliminary but provide a number of candidate genes which may be related to distinct phenotypic stage expression. This comprehensive transcriptome catalogue will provide an important gene discovery resource for directed programmes in ecology, evolution and conservation of a key pollinator.


Assuntos
Abelhas/genética , Perfilação da Expressão Gênica , Transcriptoma , Animais , Abelhas/fisiologia , DNA Complementar , Etiquetas de Sequências Expressas , Feminino , Larva/metabolismo , Masculino , RNA Mensageiro
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA