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1.
Support Care Cancer ; 32(6): 388, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802666

RESUMO

BACKGROUND: Dance/movement therapy (DMT) is increasingly used as a complementary treatment to address psychological and physical wellbeing. However, it is unknown how it can be leveraged in adult cancer care. This mixed methods program evaluation aimed to assess patient-reported benefits and satisfaction with the virtual DMT in an academic oncology setting. METHODS: We developed, implemented, and evaluated a 6-week virtual, synchronous DMT program aiming to improve physical health, address mental distress, and foster social connection for cancer patients. We used deidentified program evaluation data to assess impact of DMT on patient-reported outcomes and patients' satisfaction with the DMT program. Pre- and post-session data were analyzed using descriptive statistics and a paired t-test. Qualitative data were captured through semi-structured interviews and analyzed using thematic analysis. RESULTS: Results from 39 participants (mean age 64.7 ± 9.8), majority female (89.7%) with a history of breast cancer (43.6%), showed high satisfaction (100%) and unanimous program recommendation (100%). Significant improvements were noted in anxiety (- 0.42 ± 0.76, p = .009), distress (- 0.35 ± 0.80, p = .036), and sense of joy (0.73 ± 1.18, p = .004), with a non-significant trend in increased physical activity (0.38 ± 0.98, p = .057). Thematic findings indicated that DMT participation (1) facilitated engagement in physical activity for improved physical health, (2) fostered creative expression, (3) improved mental state, and (4) helped build social connections and support. CONCLUSION: Our DMT program shows promise as a component of integrative cancer care. The mixed-method evaluation provides insightful information to generate hypotheses for future RCT studies aiming to evaluate the specific effects of DMT on patient experience and outcomes.


Assuntos
Dançaterapia , Neoplasias , Satisfação do Paciente , Avaliação de Programas e Projetos de Saúde , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Dançaterapia/métodos , Neoplasias/terapia , Neoplasias/psicologia , Idoso , Medidas de Resultados Relatados pelo Paciente , Técnicas de Exercício e de Movimento/métodos , Adulto
2.
Clin Cancer Res ; 30(4): 904-917, 2024 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-38109212

RESUMO

PURPOSE: The gut microbiota plays important roles in health and disease. We questioned whether the gut microbiota and related metabolites are altered in monoclonal gammopathies and evaluated their potential role in multiple myeloma and its response to treatment. EXPERIMENTAL DESIGN: We used 16S rRNA sequencing to characterize and compare the gut microbiota of patients with monoclonal gammopathy of undetermined significance (n = 11), smoldering multiple myeloma (n = 9), newly diagnosed multiple myeloma (n = 11), relapsed/refractory multiple myeloma (n = 6), or with complete remission (n = 9). Short-chain fatty acids (SCFA) were quantified in serum and tested in cell lines. Relevant metabolites were validated in a second cohort of 62 patients. RESULTS: Significant differences in alpha- and beta diversity were present across the groups and both were lower in patients with relapse/refractory disease and higher in patients with complete remission after treatment. Differences were found in the abundance of several microbiota taxa across disease progression and in response to treatment. Bacteria involved in SCFA production, including Prevotella, Blautia, Weissella, and Agathobacter, were more represented in the premalignant or complete remission samples, and patients with higher levels of Agathobacter showed better overall survival. Serum levels of butyrate and propionate decreased across disease progression and butyrate was positively associated with a better response. Both metabolites had antiproliferative effects in multiple myeloma cell lines. CONCLUSIONS: We demonstrate that SCFAs metabolites and the gut microbiota associated with their production might have beneficial effects in disease evolution and response to treatment, underscoring its therapeutic potential and value as a predictor.


Assuntos
Microbioma Gastrointestinal , Mieloma Múltiplo , Humanos , Mieloma Múltiplo/tratamento farmacológico , RNA Ribossômico 16S/genética , Recidiva Local de Neoplasia , Ácidos Graxos Voláteis/metabolismo , Butiratos , Progressão da Doença , Resposta Patológica Completa
3.
ACS Omega ; 7(11): 9964-9972, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35356692

RESUMO

Telomerase overexpression has been associated directly with cancer, and the enzyme itself is recognized within the scientific community as a cancer biomarker. BIDEA's biosensing strip (BBS) is an innovative technology capable of detecting the presence of telomerase activity (TA) using electrochemical impedance spectroscopy (EIS). This BBS is an interdigital gold (GID) electrode array similar in size and handling to a portable glucose sensor. For the detection of the biomarker, BBS was modified by the immobilization of a telomere-like single strand DNA (ssDNA) on its surface. The sensor was exposed to telomerase-positive extract from commercially available cancer cells, and the EIS spectra were measured. Telomerase recognizes the sequence of this immobilized ssDNA probe on the BBS, and the reverse transcription process that occurs in cancer cells is replicated, resulting in the ssDNA probe elongation. This surface process caused by the presence of TA generates changes in the capacitive process on the electrode array microchip surface, which is followed by EIS as the sensing tool and correlated with the presence of cancer cells. The telomerases' total cell extraction protocol results demonstrate significant changes in the charge-transfer resistance (R ct) change rate after exposure to telomerase-positive extract with a detection limit of 2.94 × 104 cells/mL. Finally, a preliminary study with a small set of "blind" uterine biopsy samples suggests the feasibility of using the changes in the R ct magnitude change rate (Δ(ΔR ct/R cti)/Δt) to distinguish positive from negative endometrial adenocarcinoma samples by the presence or absence of TA.

4.
Plant J ; 109(4): 844-855, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34807484

RESUMO

l-Tyrosine is an essential amino acid for protein synthesis and is also used in plants to synthesize diverse natural products. Plants primarily synthesize tyrosine via TyrA arogenate dehydrogenase (TyrAa or ADH), which are typically strongly feedback inhibited by tyrosine. However, two plant lineages, Fabaceae (legumes) and Caryophyllales, have TyrA enzymes that exhibit relaxed sensitivity to tyrosine inhibition and are associated with elevated production of tyrosine-derived compounds, such as betalain pigments uniquely produced in core Caryophyllales. Although we previously showed that a single D222N substitution is primarily responsible for the deregulation of legume TyrAs, it is unknown when and how the deregulated Caryophyllales TyrA emerged. Here, through phylogeny-guided TyrA structure-function analysis, we found that functionally deregulated TyrAs evolved early in the core Caryophyllales before the origin of betalains, where the E208D amino acid substitution in the active site, which is at a different and opposite location from D222N found in legume TyrAs, played a key role in the TyrA functionalization. Unlike legumes, however, additional substitutions on non-active site residues further contributed to the deregulation of TyrAs in Caryophyllales. The introduction of a mutation analogous to E208D partially deregulated tyrosine-sensitive TyrAs, such as Arabidopsis TyrA2 (AtTyrA2). Moreover, the combined introduction of D222N and E208D additively deregulated AtTyrA2, for which the expression in Nicotiana benthamiana led to highly elevated accumulation of tyrosine in planta. The present study demonstrates that phylogeny-guided characterization of key residues underlying primary metabolic innovations can provide powerful tools to boost the production of essential plant natural products.


Assuntos
Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , Mutagênese , Plantas/genética , Plantas/metabolismo , Tirosina/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis , Betalaínas/biossíntese , Caryophyllales/genética , Caryophyllales/metabolismo , Fabaceae , Complexos Multienzimáticos/classificação , Oxirredutases/genética , Oxirredutases/metabolismo , Filogenia , Prefenato Desidrogenase/genética , Prefenato Desidrogenase/metabolismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-34948600

RESUMO

The present industrial food-production system is not suitably ecological for the environment. Mindful nutrition in sport is a relevant emergent sub-discipline that could help reduce environmental degradation. This case study describes a sustainable support diet during an ultra-endurance running (UR) event called the "Indoor Everest Challenge". This UR challenge involved attaining the altitude of Mount Everest (8849 m) in a simulated way, in less than 24 h, without using ultra-processed food and without wasting plastics. During this challenge, a male athlete (34 years, weight: 78 kg, and height: 173 cm) wore a SenseWear Armband® (BodyMedia Inc., Pittsburg, PA, USA) accelerometer on his right arm to estimate energy expenditure. To supply his nutritional requirements, the athlete consumed only specially prepared homemade and organic food. All consumption was weighed and recorded in real-time; we determined nutrients using two databases: a food composition software, Dial Alce Ingenieria® (Madrid, Spain), to measure energy and macro- and micro-nutrients, and Phenol Explorer Database® (INRA Institut National de Recherche pour l'Alimentation, Paris, France) precisely to determine polyphenolic content. Most energy intake (up to 96%) came from plant foods. We found that subject consumed 15.8 g/kg-1/d-1 or 1242 g of carbohydrates (CHO), (2.4 g/kg-1/d-1) or 190 g of proteins (P), and 10,692 mL of fluid. The total energy intake (7580 kcal) showed a distribution of 65% CHO, 10% P, and 25% lipids (L). Furthermore, this sustainable diet lead to a high antioxidant intake, specifically vitamin C (1079 mg), vitamin E (57 mg), and total polyphenols (1910 mg). This sustainable approach was suitable for meeting energy, CHO, and P recommendations for UR. Physical and mental training (mindfulness) were integrated from the specific preliminary phase to the day of the challenge. The athlete completed this challenge in 18 h with a low environmental impact. This sports event had an educational component, as it awakened curiosity towards food sustainability.


Assuntos
Atenção Plena , Corrida , Dieta , Ingestão de Energia , Fast Foods , Humanos , Masculino , Resistência Física , Espanha
6.
Plant J ; 107(5): 1283-1298, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34250670

RESUMO

Cadaverine, a polyamine, has been linked to modification of root growth architecture and response to environmental stresses in plants. However, the molecular mechanisms that govern the regulation of root growth by cadaverine are largely unexplored. Here we conducted a forward genetic screen and isolated a mutation, cadaverine hypersensitive 3 (cdh3), which resulted in increased root-growth sensitivity to cadaverine, but not other polyamines. This mutation affects the BIO3-BIO1 biotin biosynthesis gene. Exogenous supply of biotin and a pathway intermediate downstream of BIO1, 7,8-diaminopelargonic acid, suppressed this cadaverine sensitivity phenotype. An in vitro enzyme assay showed cadaverine inhibits the BIO3-BIO1 activity. Furthermore, cadaverine-treated seedlings displayed reduced biotinylation of Biotin Carboxyl Carrier Protein 1 of the acetyl-coenzyme A carboxylase complex involved in de novo fatty acid biosynthesis, resulting in decreased accumulation of triacylglycerides. Taken together, these results revealed an unexpected role of cadaverine in the regulation of biotin biosynthesis, which leads to modulation of primary root growth of plants.


Assuntos
Acetil-CoA Carboxilase/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Biotina/biossíntese , Cadaverina/metabolismo , Carbono-Nitrogênio Ligases/metabolismo , Transaminases/metabolismo , Acetil-CoA Carboxilase/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Biotinilação , Carbono-Nitrogênio Ligases/genética , Ácido Graxo Sintase Tipo II/genética , Ácido Graxo Sintase Tipo II/metabolismo , Ácidos Graxos/metabolismo , Regulação da Expressão Gênica de Plantas , Mutação , Fenótipo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Transaminases/genética
8.
Viruses ; 13(5)2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33924875

RESUMO

Hand, foot, and mouth disease (HFMD) is a mild illness caused by enteroviruses (EV), although in some Asian countries, large outbreaks have been reported in the last 25 years, with a considerable incidence of neurological complications. This study describes epidemiological and clinical characteristics of EV infections involved in HFMD and other mucocutaneous symptoms from 2006 to 2020 in Spain. EV-positive samples from 368 patients were included. EV species A were identified in 85.1% of those typed EV. Coxsackievirus (CV) A6 was the prevalent serotype (60.9%), followed by EV-A71 (9.9%) and CVA16 (7.7%). Infections affected children (1-6 years old) mainly, and show seasonality with peaks in spring-summer and autumn. Clinical data indicated few cases of atypical HFMD as well as those with neurological complications (associated with the 2016 EV-A71 outbreak). Phylogenetic analysis of CVA6 VP1 sequences showed different sub-clusters circulating from 2010 to present. In conclusion, HFMD or exanthemas case reporting has increased in Spain in recent years, probably associated with an increase in circulation of CVA6, although they did not seem to show greater severity. However, EV surveillance in mucocutaneous manifestations should be improved to identify the emergence of new types or variants causing outbreaks and more severe pathologies.


Assuntos
Enterovirus/genética , Enterovirus/isolamento & purificação , Doença de Mão, Pé e Boca/virologia , Filogenia , Adolescente , Criança , Pré-Escolar , Surtos de Doenças , Enterovirus/classificação , Infecções por Enterovirus/epidemiologia , Infecções por Enterovirus/virologia , Feminino , Genótipo , Doença de Mão, Pé e Boca/epidemiologia , Humanos , Lactente , Recém-Nascido , Masculino , Mucosa/virologia , Estações do Ano , Sorogrupo , Espanha/epidemiologia
9.
Int J Pharm Compd ; 24(5): 358-364, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32886632

RESUMO

When using ventilators in the management of the coronavirus disease 2019 patient, dense and abundant mucous secretions are formed, obstructing the endotracheal tube and making its aspiration difficult. This situation is worsened if in order to minimize the risk of infection of the medical personnel, the humidifier is disconnected. This circumstance forces the tube to be removed, cleaned, or changed, increasing the workload of the intensive care unit staff. Other therapies tested until now, like mesna, acetylcysteine, or hypertonic saline solution, are valid alternatives, although they have not shown great efficacy for this specific procedure in the past. The sanitary emergency forced the collaboration between a pharmacist and an otorhinolaryngologist to develop the cocamidopropyl betaine surfactant formula, after several tests with different concentrations of the surfactant. The objective of this compounding formula was to resolve a mechanical problem and avoid reintubation due to obstruction of the ventilator tube. The cocamidopropyl betaine surfactant solution 0.075% in saline 0.9% (physiological serum) solution demonstrated to be a well-tolerated formula, using inexpensive materials, was simple to prepare, and was easy to use in clinical practice.


Assuntos
Betaína/análogos & derivados , Infecções por Coronavirus/terapia , Contaminação de Equipamentos/prevenção & controle , Intubação Intratraqueal , Pneumonia Viral/terapia , Tensoativos/farmacologia , Betacoronavirus , Betaína/farmacologia , COVID-19 , Humanos , Higiene , Pandemias , SARS-CoV-2 , Ventiladores Mecânicos
11.
Echocardiography ; 37(6): 850-857, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32433805

RESUMO

OBJECTIVE: Morphological and functional right ventricular (RV) changes during normal pregnancy remain poorly characterized. Similar to left ventricle, RV load and function are expected to change, and establishing reference values for RV during a healthy pregnancy is critical for the evaluation of pregnancy-related heart disease. The aim of the study was to describe RV adaptation in a prospective cohort. METHODS: Serial echocardiographic examinations were performed in second trimester (24 ± 2 weeks), third (32 ± 2 week) trimester, and postpartum (>3 months after delivery). Nulliparous women were evaluated as control group. RV linear dimensions, areas, and function were assessed and compared. RESULTS: Forty-three pregnant women were evaluated and compared with nineteen nulliparous women as control. Function parameters decreased along gestation. RV fractional area fell from second to third trimester (52.01 ± 0.92 vs 48.73 ± 0.97, P < .05), as well as tricuspid annular plane systolic excursion (2.62 ± 0.05 vs 2.41 ± 0.05, P < .05); however, RV longitudinal strain (L) decreased earlier, showing main changes from second trimester (26.17 ± 0.86 vs 22.71 ± 0.57, P < .003, control vs second trimester). S'-wave velocity followed a different pattern without changes during pregnancy. RV diameters significantly increased during pregnancy: basal (3.65 ± 0.06 vs 3.90 ± 0.06, P < .05), mid- (2.70 ± 0.06 vs 3.00 ± 0.07, P < .05), longitudinal (6.90 ± 0.09 vs 7.32 ± 0.11, P < .05), and right ventricle outflow tract proximal diameter (3.20 ± 0.06 vs 3.44 ± 0.06, P < .05). RV areas also suffered early variation during pregnancy. In postpartum evaluation, all these changes were reversed. CONCLUSION: During pregnancy, RV experiments important variations. RV size increases, and its function decreases. Changes in LS were earlier compared with other function measures.


Assuntos
Ventrículos do Coração , Função Ventricular Direita , Ecocardiografia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Gravidez , Estudos Prospectivos , Valores de Referência
12.
Circ Cardiovasc Interv ; 13(4): e008487, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32295416

RESUMO

Fractional flow reserve is the current invasive gold standard for assessing the ischemic potential of an angiographically intermediate coronary stenosis. Procedural cost and time, the need for coronary vessel instrumentation, and the need to administer adenosine to achieve maximal hyperemia remain integral components of invasive fractional flow reserve. The number of new alternatives to fractional flow reserve has proliferated over the last ten years using techniques ranging from alternative pressure wire metrics to anatomic simulation via angiography or intravascular imaging. This review article provides a critical description of the currently available or under-development alternatives to fractional flow reserve with a special focus on the available evidence, pros, and cons for each with a view towards their clinical application in the near future for the functional assessment of coronary artery disease.


Assuntos
Cateterismo Cardíaco , Técnicas de Imagem Cardíaca , Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/diagnóstico por imagem , Reserva Fracionada de Fluxo Miocárdico , Cateterismo Cardíaco/instrumentação , Cateteres Cardíacos , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/fisiopatologia , Humanos , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Transdutores de Pressão
13.
Lancet Infect Dis ; 20(5): 575-584, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32087113

RESUMO

BACKGROUND: The effectiveness of contact isolation for decreasing the spread of extended-spectrum ß-lactamase-producing Enterobacterales (ESBL-E) has been questioned. The aim of this study was to establish the benefits of contact isolation over standard precautions for reducing the incidence density of ESBL-E colonisation and infection in adult medical and surgical wards with an active surveillance culture programme. METHODS: We did a cluster-randomised crossover trial in adult wards in four European university hospitals. Medical, surgical, or combined medical-surgical wards without critical care were randomised to continue standard precautions alone or implement contact isolation alongside standard precautions for 12 months, followed by a 1 month washout period and 12 months of the alternate strategy. Randomisation was done via a computer-generated sequence, with a block size of two consecutive wards. Only laboratory technicians and data analysts were masked to allocation. Patients were screened for ESBL-E carriage within 3 days of admission, once a week thereafter, and on discharge. The primary outcome was the incidence density of ESBL-E, defined as the acquisition rate per 1000 patient-days at risk at the ward level and assessed in the per-protocol population, which included all patients screened at least twice with a length of stay of more than 1 week for each intervention period. No specific safety measures were assessed given the minimal risk of adverse events. The trial is registered, ISRCTN57648070. FINDINGS: We enrolled 20 wards from four hospitals in Germany (eight wards), the Netherlands (four wards), Spain (four wards), and Switzerland (four wards). Between Jan 6, 2014, and Aug 31, 2016, 38 357 patients were admitted to these wards. Among 15 184 patients with a length of stay of more than 1 week, 11 368 patients (75%) were screened at least twice. The incidence density of ward-acquired ESBL-E was 6·0 events per 1000 patient-days at risk (95% CI 5·4-6·7) during periods of contact isolation and 6·1 (5·5-6·7) during periods of standard precautions (p=0·9710). Multivariable analysis adjusted for length of stay, percentage of patients screened, and prevalence in first screening cultures yielded an incidence rate ratio of 0·99 (95% CI 0·80-1·22; p=0·9177) for care under contact isolation compared with standard precautions. INTERPRETATION: Contact isolation showed no benefit when added to standard precautions for controlling the spread of ESBL-E on non-critical care wards with extensive surveillance screening. FUNDING: European Commission.


Assuntos
Infecção Hospitalar/prevenção & controle , Infecções por Enterobacteriaceae/prevenção & controle , Enterobacteriaceae/metabolismo , Controle de Infecções/métodos , beta-Lactamases/metabolismo , Adulto , Portador Sadio/prevenção & controle , Cuidados Críticos/métodos , Estudos Cross-Over , Feminino , Alemanha , Hospitais , Humanos , Masculino , Países Baixos , Isolamento de Pacientes/métodos , Prevalência , Quarentena , Espanha , Suíça
14.
New Phytol ; 227(3): 914-929, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31369159

RESUMO

The evolution of l-DOPA 4,5-dioxygenase activity, encoded by the gene DODA, was a key step in the origin of betalain biosynthesis in Caryophyllales. We previously proposed that l-DOPA 4,5-dioxygenase activity evolved via a single Caryophyllales-specific neofunctionalisation event within the DODA gene lineage. However, this neofunctionalisation event has not been confirmed and the DODA gene lineage exhibits numerous gene duplication events, whose evolutionary significance is unclear. To address this, we functionally characterised 23 distinct DODA proteins for l-DOPA 4,5-dioxygenase activity, from four betalain-pigmented and five anthocyanin-pigmented species, representing key evolutionary transitions across Caryophyllales. By mapping these functional data to an updated DODA phylogeny, we then explored the evolution of l-DOPA 4,5-dioxygenase activity. We find that low l-DOPA 4,5-dioxygenase activity is distributed across the DODA gene lineage. In this context, repeated gene duplication events within the DODA gene lineage give rise to polyphyletic occurrences of elevated l-DOPA 4,5-dioxygenase activity, accompanied by convergent shifts in key functional residues and distinct genomic patterns of micro-synteny. In the context of an updated organismal phylogeny and newly inferred pigment reconstructions, we argue that repeated convergent acquisition of elevated l-DOPA 4,5-dioxygenase activity is consistent with recurrent specialisation to betalain synthesis in Caryophyllales.


Assuntos
Caryophyllales , Dioxigenases , Betalaínas , Dioxigenases/genética , Levodopa , Filogenia , Pigmentação
15.
New Phytol ; 224(1): 71-85, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31172524

RESUMO

Within the angiosperm order Caryophyllales, an unusual class of pigments known as betalains can replace the otherwise ubiquitous anthocyanins. In contrast to the phenylalanine-derived anthocyanins, betalains are tyrosine-derived pigments which contain the chromophore betalamic acid. The origin of betalain pigments within Caryophyllales and their mutual exclusion with anthocyanin pigments have been the subject of considerable research. In recent years, numerous discoveries, accelerated by -omic scale data, phylogenetics and synthetic biology, have shed light on the evolution of the betalain biosynthetic pathway in Caryophyllales. These advances include the elucidation of the biosynthetic steps in the betalain pathway, identification of transcriptional regulators of betalain synthesis, resolution of the phylogenetic history of key genes, and insight into a role for modulation of primary metabolism in betalain synthesis. Here we review how molecular genetics have advanced our understanding of the betalain biosynthetic pathway, and discuss the impact of phylogenetics in revealing its evolutionary history. In light of these insights, we explore our new understanding of the origin of betalains, the mutual exclusion of betalains and anthocyanins, and the homoplastic distribution of betalain pigmentation within Caryophyllales. We conclude with a speculative conceptual model for the stepwise emergence of betalain pigmentation.


Assuntos
Betalaínas/biossíntese , Evolução Biológica , Caryophyllales/metabolismo , Betalaínas/química , Vias Biossintéticas , Caryophyllales/genética , Filogenia , Pigmentação/genética
16.
Arch Biochem Biophys ; 665: 12-19, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30771296

RESUMO

L-Tyrosine is an aromatic amino acid necessary for protein synthesis in all living organisms and a precursor of secondary (specialized) metabolites. In fungi, tyrosine-derived compounds are associated with virulence and defense (i.e. melanin production). However, how tyrosine is produced in fungi is not fully understood. Generally, tyrosine can be synthesized via two pathways: by prephenate dehydrogenase (TyrAp/PDH), a pathway found in most bacteria, or by arogenate dehydrogenase (TyrAa/ADH), a pathway found mainly in plants. Both enzymes require the cofactor NAD+ or NADP+ and typically are strongly feedback inhibited by tyrosine. Here, we biochemically characterized two TyrA enzymes from two distantly related fungi in the Ascomycota and Basidiomycota, Saccharomyces cerevisiae (ScTyrA/TYR1) and Pleurotus ostreatus (PoTyrA), respectively. We found that both enzymes favor the prephenate substrate and NAD+ cofactor in vitro. Interestingly, while PoTyrA was strongly inhibited by tyrosine, ScTyrA exhibited relaxed sensitivity to tyrosine inhibition. We further mutated ScTyrA at the amino acid residue that was previously shown to be involved in the substrate specificity of plant TyrAs; however, no changes in its substrate specificity were observed, suggesting that a different mechanism is involved in the TyrA substrate specificity of fungal TyrAs. The current findings provide foundational knowledge to further understand and engineer tyrosine-derived specialized pathways in fungi.


Assuntos
Proteínas Fúngicas/metabolismo , Oxirredutases/metabolismo , Pleurotus/enzimologia , Saccharomyces cerevisiae/enzimologia , Proteínas Fúngicas/antagonistas & inibidores , Cinética , NAD/metabolismo , Oxirredutases/antagonistas & inibidores , Especificidade por Substrato , Tirosina/metabolismo
17.
Sci Rep ; 8(1): 17256, 2018 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-30467357

RESUMO

L-Tyrosine-derived specialized metabolites perform many important functions in plants, and have valuable applications in human health and nutrition. A necessary step in the overproduction of specialised tyrosine-derived metabolites in planta is the manipulation of primary metabolism to enhance the availability of tyrosine. Here, we utilise a naturally occurring de-regulated isoform of the key enzyme, arogenate dehydrogenase, to re-engineer the interface of primary and specialised metabolism, to boost the production of tyrosine-derived pigments in a heterologous plant host. Through manipulation of tyrosine availability, we report a 7-fold increase in the production of tyrosine-derived betalain pigments, with an upper range of 855 mg·kg-1·FW, which compare favourably to many in vitro and commercial sources of betalain pigments. Since the most common plant pathway for tyrosine synthesis occurs via arogenate, the de-regulated arogenate dehydrogenase isoform is a promising route for enhanced production of tyrosine-derived pharmaceuticals in diverse plant hosts.


Assuntos
Beta vulgaris/crescimento & desenvolvimento , Betalaínas/metabolismo , Nicotiana/crescimento & desenvolvimento , Prefenato Desidrogenase/metabolismo , Metabolismo Basal , Beta vulgaris/genética , Beta vulgaris/metabolismo , Engenharia Metabólica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Prefenato Desidrogenase/genética , Isoformas de Proteínas/metabolismo , Metabolismo Secundário , Nicotiana/genética , Nicotiana/metabolismo , Tirosina/metabolismo
18.
Bioelectrochemistry ; 122: 206-212, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29679910

RESUMO

One of the most challenging problems when trying to recycle urine for different purposes is the removal of urea. In this project we studied an ureolysis system using the bacterium Proteus vulgaris for the transformation of urea to ammonia and its subsequent oxidation to nitrogen at a Pt working electrode. Our system was tested under different pH, microbial reaction times, and urea and bacteria concentrations. Our results indicate that a pH8 is optimal for the combined Proteus vulgaris urease activity and the ammonia oxidation reaction at a Pt electrode. The reaction time and concentration dependence on the ammonia oxidation reaction current densities was also studied. Results showed limited ammonia oxidation under high urea concentrations in ~2.5×109cfu/mL Proteus vulgaris in synthetic urine.


Assuntos
Amônia/metabolismo , Nitrogênio/metabolismo , Proteus vulgaris/metabolismo , Ureia/metabolismo , Biotransformação , Técnicas Eletroquímicas , Eletrodos , Concentração de Íons de Hidrogênio , Oxirredução , Platina/química
19.
New Phytol ; 217(2): 896-908, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28990194

RESUMO

Diverse natural products are synthesized in plants by specialized metabolic enzymes, which are often lineage-specific and derived from gene duplication followed by functional divergence. However, little is known about the contribution of primary metabolism to the evolution of specialized metabolic pathways. Betalain pigments, uniquely found in the plant order Caryophyllales, are synthesized from the aromatic amino acid l-tyrosine (Tyr) and replaced the otherwise ubiquitous phenylalanine-derived anthocyanins. This study combined biochemical, molecular and phylogenetic analyses, and uncovered coordinated evolution of Tyr and betalain biosynthetic pathways in Caryophyllales. We found that Beta vulgaris, which produces high concentrations of betalains, synthesizes Tyr via plastidic arogenate dehydrogenases (TyrAa /ADH) encoded by two ADH genes (BvADHα and BvADHß). Unlike BvADHß and other plant ADHs that are strongly inhibited by Tyr, BvADHα exhibited relaxed sensitivity to Tyr. Also, Tyr-insensitive BvADHα orthologs arose during the evolution of betalain pigmentation in the core Caryophyllales and later experienced relaxed selection and gene loss in lineages that reverted from betalain to anthocyanin pigmentation, such as Caryophyllaceae. These results suggest that relaxation of Tyr pathway regulation increased Tyr production and contributed to the evolution of betalain pigmentation, highlighting the significance of upstream primary metabolic regulation for the diversification of specialized plant metabolism.


Assuntos
Betalaínas/biossíntese , Vias Biossintéticas/genética , Caryophyllales/genética , Evolução Molecular , Pigmentação/genética , Tirosina/metabolismo , Antocianinas/metabolismo , Beta vulgaris/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Filogenia , Plastídeos/enzimologia , Prefenato Desidrogenase/genética , Prefenato Desidrogenase/metabolismo , Spinacia oleracea/enzimologia , Spinacia oleracea/genética
20.
Photosynth Res ; 121(2-3): 311-22, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24844569

RESUMO

Carbon concentrating mechanisms (CCMs) are common among microalgae, but their regulation and even existence in some of the most promising biofuel production strains is poorly understood. This is partly because screening for new strains does not commonly include assessment of CCM function or regulation despite its fundamental role in primary carbon metabolism. In addition, the inducible nature of many microalgal CCMs means that environmental conditions should be considered when assessing CCM function and its potential impact on biofuels. In this study, we address the effect of environmental conditions by combining novel, high frequency, on-line (13)CO2 gas exchange screen with microscope-based lipid characterization to assess CCM function in Nannochloropsis salina and its interaction with lipid production. Regulation of CCM function was explored by changing the concentration of CO2 provided to continuous cultures in airlift bioreactors where cell density was kept constant across conditions by controlling the rate of media supply. Our isotopic gas exchange results were consistent with N. salina having an inducible "pump-leak" style CCM similar to that of Nannochloropsis gaditana. Though cells grew faster at high CO2 and had higher rates of net CO2 uptake, we did not observe significant differences in lipid content between conditions. Since the rate of CO2 supply was much higher for the high CO2 conditions, we calculated that growing cells bubbled with low CO2 is about 40 % more efficient for carbon capture than bubbling with high CO2. We attribute this higher efficiency to the activity of a CCM under low CO2 conditions.


Assuntos
Carbono/metabolismo , Microalgas/metabolismo , Dióxido de Carbono/metabolismo , Fotossíntese
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