RESUMO
YEASTRACT+ (http://yeastract-plus.org/) is a tool for the analysis, prediction and modelling of transcription regulatory data at the gene and genomic levels in yeasts. It incorporates three integrated databases: YEASTRACT (http://yeastract-plus.org/yeastract/), PathoYeastract (http://yeastract-plus.org/pathoyeastract/) and NCYeastract (http://yeastract-plus.org/ncyeastract/), focused on Saccharomyces cerevisiae, pathogenic yeasts of the Candida genus, and non-conventional yeasts of biotechnological relevance. In this release, YEASTRACT+ offers upgraded information on transcription regulation for the ten previously incorporated yeast species, while extending the database to another pathogenic yeast, Candida auris. Since the last release of YEASTRACT+ (January 2020), a fourth database has been integrated. CommunityYeastract (http://yeastract-plus.org/community/) offers a platform for the creation, use, and future update of YEASTRACT-like databases for any yeast of the users' choice. CommunityYeastract currently provides information for two Saccharomyces boulardii strains, Rhodotorula toruloides NP11 oleaginous yeast, and Schizosaccharomyces pombe 972h-. In addition, YEASTRACT+ portal currently gathers 304 547 documented regulatory associations between transcription factors (TF) and target genes and 480 DNA binding sites, considering 2771 TFs from 11 yeast species. A new set of tools, currently implemented for S. cerevisiae and C. albicans, is further offered, combining regulatory information with genome-scale metabolic models to provide predictions on the most promising transcription factors to be exploited in cell factory optimisation or to be used as novel drug targets. The expansion of these new tools to the remaining YEASTRACT+ species is ongoing.
Assuntos
Software , Transcrição Gênica , Leveduras , Bases de Dados Genéticas , Regulação Fúngica da Expressão Gênica , Redes Reguladoras de Genes , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Leveduras/genéticaRESUMO
Maintenance of asymmetric ion concentrations across cellular membranes is crucial for proper yeast cellular function. Disruptions of these ionic gradients can significantly impact membrane electrochemical potential and the balance of other ions, particularly under stressful conditions such as exposure to acetic acid. This weak acid, ubiquitous to both yeast metabolism and industrial processes, is a major inhibitor of yeast cell growth in industrial settings and a key determinant of host colonization by pathogenic yeast. Acetic acid toxicity depends on medium composition, especially on the pH (H+ concentration), but also on other ions' concentrations. Regulation of ion fluxes is essential for effective yeast response and adaptation to acetic acid stress. However, the intricate interplay among ion balancing systems and stress response mechanisms still presents significant knowledge gaps. This review offers a comprehensive overview of the mechanisms governing ion homeostasis, including H+, K+, Zn2+, Fe2+/3+, and acetate, in the context of acetic acid toxicity, adaptation, and tolerance. While focus is given on Saccharomyces cerevisiae due to its extensive physiological characterization, insights are also provided for biotechnologically and clinically relevant yeast species whenever available.
Assuntos
Ácido Acético , Adaptação Fisiológica , Homeostase , Íons , Saccharomyces cerevisiae , Estresse Fisiológico , Ácido Acético/metabolismo , Ácido Acético/farmacologia , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/crescimento & desenvolvimento , Íons/metabolismo , Concentração de Íons de HidrogênioRESUMO
Glial cells are essential for functionality of the nervous system. Growing evidence underscores the importance of astrocytes; however, analogous astroglia in peripheral organs are poorly understood. Using confocal time-lapse imaging, fate mapping, and mutant genesis in a zebrafish model, we identify a neural crest-derived glial cell, termed nexus glia, which utilizes Meteorin signaling via Jak/Stat3 to drive differentiation and regulate heart rate and rhythm. Nexus glia are labeled with gfap, glast, and glutamine synthetase, markers that typically denote astroglia cells. Further, analysis of single-cell sequencing datasets of human and murine hearts across ages reveals astrocyte-like cells, which we confirm through a multispecies approach. We show that cardiac nexus glia at the outflow tract are critical regulators of both the sympathetic and parasympathetic system. These data establish the crucial role of glia on cardiac homeostasis and provide a description of nexus glia in the PNS.
Assuntos
Astrócitos/citologia , Coração/embriologia , Neuroglia/citologia , Animais , Astrócitos/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Coração/fisiologia , Frequência Cardíaca/fisiologia , Ventrículos do Coração/metabolismo , Humanos , Camundongos , Miócitos Cardíacos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Crista Neural/metabolismo , Neuroglia/metabolismo , Neurônios/metabolismo , Sistema Nervoso Parassimpático/fisiologia , Transdução de Sinais , Especificidade da Espécie , Sistema Nervoso Simpático/fisiologia , Peixe-ZebraRESUMO
BACKGROUND: The improvement of yeast tolerance to acetic, butyric, and octanoic acids is an important step for the implementation of economically and technologically sustainable bioprocesses for the bioconversion of renewable biomass resources and wastes. To guide genome engineering of promising yeast cell factories toward highly robust superior strains, it is instrumental to identify molecular targets and understand the mechanisms underlying tolerance to those monocarboxylic fatty acids. A chemogenomic analysis was performed, complemented with physiological studies, to unveil genetic tolerance determinants in the model yeast and cell factory Saccharomyces cerevisiae exposed to equivalent moderate inhibitory concentrations of acetic, butyric, or octanoic acids. RESULTS: Results indicate the existence of multiple shared genetic determinants and pathways underlying tolerance to these short- and medium-chain fatty acids, such as vacuolar acidification, intracellular trafficking, autophagy, and protein synthesis. The number of tolerance genes identified increased with the linear chain length and the datasets for butyric and octanoic acids include the highest number of genes in common suggesting the existence of more similar toxicity and tolerance mechanisms. Results of this analysis, at the systems level, point to a more marked deleterious effect of an equivalent inhibitory concentration of the more lipophilic octanoic acid, followed by butyric acid, on the cell envelope and on cellular membranes function and lipid remodeling. The importance of mitochondrial genome maintenance and functional mitochondria to obtain ATP for energy-dependent detoxification processes also emerged from this chemogenomic analysis, especially for octanoic acid. CONCLUSIONS: This study provides new biological knowledge of interest to gain further mechanistic insights into toxicity and tolerance to linear-chain monocarboxylic acids of increasing liposolubility and reports the first lists of tolerance genes, at the genome scale, for butyric and octanoic acids. These genes and biological functions are potential targets for synthetic biology approaches applied to promising yeast cell factories, toward more robust superior strains, a highly desirable phenotype to increase the economic viability of bioprocesses based on mixtures of volatiles/medium-chain fatty acids derived from low-cost biodegradable substrates or lignocellulose hydrolysates.
Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Caprilatos/metabolismo , Caprilatos/farmacologia , Ácidos Graxos/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMO
We report the synthesis and characterization of three novel Schiff bases (L1-L3) derived from the condensation of 2-carbaldehyde-8-hydroxyquinoline with amines containing morpholine or piperidine moieties. These were reacted with CuCl2 and ZnCl2 yielding six new coordination compounds, with the general formula ML2, where M = Cu(II) or Zn(II) and L = L1-L3, which were all characterized by analytical, spectroscopic (Fourier transform infrared (FTIR), UV-visible absorption, nuclear magnetic resonance (NMR), or electron paramagnetic resonance (EPR)), and mass spectrometric techniques, as well as by single-crystal X-ray diffraction. In the solid state, two Cu(II) complexes, with L1 and L2, are obtained as dinuclear compounds, with relatively short Cu-Cu distances (3.146 and 3.171 Å for Cu2(L1)4 and Cu2(L2)4, respectively). The free ligands show moderate lipophilicity, while their complexes are more lipophilic. The pKa values of L1-L3 and formation constants of the complex (for ML and ML2) species were determined by spectrophotometric titrations, with the Cu(II) complexes showing higher stability than the Zn(II) complexes. EPR indicated the presence of several species in solution as pH varied and binding modes were proposed. The binding of the complexes to bovine serum albumin (BSA) was evaluated by fluorescence and circular dichroism (CD) spectroscopies. All complexes bind BSA, and as demonstrated by CD, the process takes several hours to reach equilibrium. The antiproliferative activity was evaluated in malignant melanoma cells (A375) and in noncancerous keratinocytes (HaCaT). All complexes display significant cytotoxicity (IC50 < 10 µM) but modest selectivity. The complexes show higher activity than the free ligands, the Cu(II) complexes being more active than the Zn(II) complexes, and approximately twice more cytotoxic than cisplatin. A Guava ViaCount assay corroborated the antiproliferative activity.
Assuntos
Complexos de Coordenação , Complexos de Coordenação/química , Bases de Schiff/química , Ligantes , Oxiquinolina/farmacologia , Zinco/química , Cobre/farmacologia , Cobre/químicaRESUMO
A series of mononuclear non-oxido vanadium(IV) complexes, [VIV(L1-4)2] (1-4), featuring tridentate bi-negative ONS chelating S-alkyl/aryl-substituted dithiocarbazate ligands H2L1-4, are reported. All the synthesized non-oxido VIV compounds are characterized by elemental analysis, spectroscopy (IR, UV-vis, and EPR), ESI-MS, as well as electrochemical techniques (cyclic voltammetry). Single-crystal X-ray diffraction studies of 1-3 reveal that the mononuclear non-oxido VIV complexes show distorted octahedral (1 and 2) or trigonal prismatic (3) arrangement around the non-oxido VIV center. EPR and DFT data indicate the coexistence of mer and fac isomers in solution, and ESI-MS results suggest a partial oxidation of [VIV(L1-4)2] to [VV(L1-4)2]+ and [VVO2(L1-4)]-; therefore, all these three complexes are plausible active species. Complexes 1-4 interact with bovine serum albumin (BSA) with a moderate binding affinity, and docking calculations reveal non-covalent interactions with different regions of BSA, particularly with Tyr, Lys, Arg, and Thr residues. In vitro cytotoxic activity of all complexes is assayed against the HT-29 (colon cancer) and HeLa (cervical cancer) cells and compared with the NIH-3T3 (mouse embryonic fibroblast) normal cell line by MTT assay and DAPI staining. The results suggest that complexes 1-4 are cytotoxic in nature and induce cell death in the cancer cell lines by apoptosis and that a mixture of VIV, VV, and VVO2 species could be responsible for the biological activity.
Assuntos
Complexos de Coordenação , Camundongos , Humanos , Animais , Complexos de Coordenação/química , Fibroblastos , Células HeLa , Vanádio/química , Quelantes , LigantesRESUMO
AIMS/HYPOTHESIS: Imbalances in glucose metabolism are hallmarks of clinically silent prediabetes (defined as impaired fasting glucose and/or impaired glucose tolerance) representing dysmetabolism trajectories leading to type 2 diabetes. CD26/dipeptidyl peptidase 4 (DPP4) is a clinically proven molecular target of diabetes-controlling drugs but the DPP4 gene control of dysglycaemia is not proven. METHODS: We dissected the genetic control of post-OGTT and insulin release responses by the DPP4 gene in a Portuguese population-based cohort of mainly European ancestry that comprised individuals with normoglycaemia and prediabetes, and in mouse experimental models of Dpp4 deficiency and hyperenergetic diet. RESULTS: In individuals with normoglycaemia, DPP4 single-nucleotide variants governed glycaemic excursions (rs4664446, p=1.63x10-7) and C-peptide release responses (rs2300757, p=6.86x10-5) upon OGTT. Association with blood glucose levels was stronger at 30 min OGTT, but a higher association with the genetic control of insulin secretion was detected in later phases of the post-OGTT response, suggesting that the DPP4 gene directly senses glucose challenges. Accordingly, in mice fed a normal chow diet but not a high-fat diet, we found that, under OGTT, expression of Dpp4 is strongly downregulated at 30 min in the mouse liver. Strikingly, no genetic association was found in prediabetic individuals, indicating that post-OGTT control by DPP4 is abrogated in prediabetes. Furthermore, Dpp4 KO mice provided concordant evidence that Dpp4 modulates post-OGTT C-peptide release in normoglycaemic but not dysmetabolic states. CONCLUSIONS/INTERPRETATION: These results showed the DPP4 gene as a strong determinant of post-OGTT levels via glucose-sensing mechanisms that are abrogated in prediabetes. We propose that impairments in DPP4 control of post-OGTT insulin responses are part of molecular mechanisms underlying early metabolic disturbances associated with type 2 diabetes.
Assuntos
Diabetes Mellitus Tipo 2 , Estado Pré-Diabético , Animais , Glicemia/metabolismo , Peptídeo C/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Dipeptidil Peptidase 4/metabolismo , Teste de Tolerância a Glucose , Humanos , Insulina/metabolismo , Secreção de Insulina/genética , Camundongos , Estado Pré-Diabético/metabolismoRESUMO
Pectin-rich plant biomass residues represent underutilized feedstocks for industrial biotechnology. The conversion of the oxidized monomer d-galacturonic acid (d-GalUA) to highly reduced fermentation products such as alcohols is impossible due to the lack of electrons. The reduced compound glycerol has therefore been considered an optimal co-substrate, and a cell factory able to efficiently co-ferment these two carbon sources is in demand. Here, we inserted the fungal d-GalUA pathway in a strain of the yeast S. cerevisiae previously equipped with an NAD-dependent glycerol catabolic pathway. The constructed strain was able to consume d-GalUA with the highest reported maximum specific rate of 0.23 g gCDW-1 h-1 in synthetic minimal medium when glycerol was added. By means of a 13C isotope-labelling analysis, carbon from both substrates was shown to end up in pyruvate. The study delivers the proof of concept for a co-fermentation of the two 'respiratory' carbon sources to ethanol and demonstrates a fast and complete consumption of d-GalUA in crude sugar beet pulp hydrolysate under aerobic conditions. The future challenge will be to achieve co-fermentation under industrial, quasi-anaerobic conditions.
Assuntos
Glicerol , Saccharomyces cerevisiae , Fermentação , Glicerol/metabolismo , Ácidos Hexurônicos , Pectinas/genética , Pectinas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismoRESUMO
We report the synthesis, characterization and biological screening of new chromone Schiff bases derived from the condensation of three 6-substituted-3-formyl-chromones with pyridoxal (HL1-3) and its Cu(II) complexes [Cu(L1-3)Cl], 1-3. For the 6-methyl derivative, HL2, the VIVO-complex [VO(L2)Cl] (5), as well as ternary Cu and VIVO complexes with 1,10-phenanthroline (phen), [Cu(L2)(phen)Cl] (4) and [VO(L2)(phen)Cl] (6), were also prepared and evaluated. Their stability in aqueous medium and radical scavenging activity toward DPPH are screened, with [Cu(L2)(phen)Cl] (4) showing hydrolytic stability and [VO(L2)(phen)Cl] (6) high radical scavenging activity. Spectroscopic studies establish bovine serum albumin (BSA), a model for HSA, as a potential reversible carrier of [Cu(L2)(phen)Cl] in blood with KBC ≈ 105 M-1. The cytotoxic activity of a group of compounds is evaluated against a panel of human cancer cell lines of different origin (ovary, cervix, brain and breast) and compared to normal cells. Our results indicate that Cu complexes are more cytotoxic than the ligands but not selective towards cancer cells. The most potent complexes (4 and 6) are further evaluated for their apoptotic potential, induction of reactive oxygen species (ROS) and genotoxicity. Both complexes efficiently triggered cell death through apoptosis as evaluated by DNA morphology and TUNEL assay, increased ROS formation as determined by DCFDA (2',7'-dichlorodihydrofluorescein diacetate) analysis, and induced genotoxic damage as visualized via COMET assay in all cancer cells under study. Therefore, 4 and 6 may be potential precursor anticancer molecules, yet they need to be targeted toward cancer cells.
Assuntos
Antineoplásicos , Complexos de Coordenação , Antineoplásicos/química , Cromonas/farmacologia , Complexos de Coordenação/química , Cobre/química , Humanos , Fenantrolinas/química , Bases de Schiff/química , Bases de Schiff/farmacologiaRESUMO
Vanadium compounds have frequently been proposed as therapeutics, but their application has been hampered by the lack of information on the different V-containing species that may form and how these interact with blood and cell proteins, and with enzymes. Herein, we report several resolved crystal structures of lysozyme with bound VIV O2+ and VIV OL2+ , where L=2,2'-bipyridine or 1,10-phenanthroline (phen), and of trypsin with VIV O(picolinato)2 and VV O2 (phen)+ moieties. Computational studies complete the refinement and shed light on the relevant role of hydrophobic interactions, hydrogen bonds, and microsolvation in stabilizating the structure. Noteworthy is that the trypsin-VV O2 (phen) and trypsin-VIV O(OH)(phen) adducts correspond to similar energies, thus suggesting a possible interconversion under physiological/biological conditions. The obtained data support the relevance of hydrolysis of VIV and VV complexes in the several types of binding established with proteins and the formation of different adducts that might contribute to their pharmacological action, and significantly widen our knowledge of vanadium-protein interactions.
Assuntos
Compostos Organometálicos , Vanádio , Compostos Organometálicos/química , Fenantrolinas , Proteínas , Tripsina , Vanádio/química , Raios XRESUMO
The species Blastobotrys navarrensis Sesma and Ramirez was delineated based on the description of the single strain CBS 139.77T. Based on its phenotypic similarities to Blastobotrys proliferans, B. navarrensis CBS 139.77T was later considered a synonym of B. proliferans. In the present study, we isolated the yeast strain IST 508 (=PYCC 8784=CBS 16671) from the soil surrounding an olive tree in Ferreira do Alentejo, Portugal. The phylogenetic analysis of D1/D2 domain and ITS sequences from strain IST 508 indicates that is closely related to B. navarrensis and B. proliferans. Although strain IST 508 differs from B. navarrensis CBS 139.77T by 14 substitutions and 20 indels (6.6 % divergence) in the ITS sequence, no divergence was detected at the level of D1/D2 domain, mitochondrial small subunit rDNA, and cytochrome oxidase II sequences. On the other hand, strains IST 508 and CBS 139.77 differ from B. proliferans NRRL Y-17577T by eight substitutions (1.4 % divergence) in the D1/D2 domain sequence, by 16 substitutions (2.7 % divergence) in the cytochrome oxidase II sequence, and by 16 substitutions (3.7 % divergence) in the mitochondrial small subunit rDNA sequence. Due to the high number of variable phenotypic tests in B. proliferans and B. navarrensis, strains from the two species are difficult to distinguish. Contrasting with what is described for other Blastobotrys species, no differences were detected at the level of micromorphology between the two species. Nevertheless, based on the molecular differences between the two strains, CBS 139.77 and IST 508, and B. proliferans NRRL Y-17577T and their phylogenetic analysis, strains CBS 139.77 and IST 508 are from B. navarrensis and this species should be considered as an independent species and not a later synonym of B. proliferans. We propose an emended description of B. navarrensis.
Assuntos
Complexo IV da Cadeia de Transporte de Elétrons , Saccharomycetales , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , DNA Fúngico/genética , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Ácidos Graxos/química , Técnicas de Tipagem Micológica , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
The YEASTRACT+ information system (http://YEASTRACT-PLUS.org/) is a wide-scope tool for the analysis and prediction of transcription regulatory associations at the gene and genomic levels in yeasts of biotechnological or human health relevance. YEASTRACT+ is a new portal that integrates the previously existing YEASTRACT (http://www.yeastract.com/) and PathoYeastract (http://pathoyeastract.org/) databases and introduces the NCYeastract (Non-Conventional Yeastract) database (http://ncyeastract.org/), focused on the so-called non-conventional yeasts. The information in the YEASTRACT database, focused on Saccharomyces cerevisiae, was updated. PathoYeastract was extended to include two additional pathogenic yeast species: Candida parapsilosis and Candida tropicalis. Furthermore, the NCYeastract database was created, including five biotechnologically relevant yeast species: Zygosaccharomyces baillii, Kluyveromyces lactis, Kluyveromyces marxianus, Yarrowia lipolytica and Komagataella phaffii. The YEASTRACT+ portal gathers 289 706 unique documented regulatory associations between transcription factors (TF) and target genes and 420 DNA binding sites, considering 247 TFs from 10 yeast species. YEASTRACT+ continues to make available tools for the prediction of the TFs involved in the regulation of gene/genomic expression. In this release, these tools were upgraded to enable predictions based on orthologous regulatory associations described for other yeast species, including two new tools for cross-species transcription regulation comparison, based on multi-species promoter and TF regulatory network analyses.
Assuntos
Biologia Computacional/métodos , Bases de Dados Genéticas , Regulação Fúngica da Expressão Gênica , Genoma Fúngico , Genômica , Leveduras/genética , Sítios de Ligação , Candida tropicalis/genética , Redes Reguladoras de Genes , Kluyveromyces/genética , Filogenia , Regiões Promotoras Genéticas , Saccharomyces cerevisiae/genética , Software , Especificidade da Espécie , Fatores de Transcrição/genética , Transcrição Gênica , Yarrowia/genética , Zygosaccharomyces/genéticaRESUMO
A 33-year-old female, Fitzpatrick IV phototype, developed varicella zoster eruption over the ophthalmic dermatome of the right trigeminal nerve, confirmed through Polymerase Chain Reaction, 4 weeks after recovering from COVID-19 disease. After the resolution of the acute manifestations, she developed significant atrophic scars on the forehead, about 2 mm deep, with marked post-inflammatory hyperpigmentation. She came to our clinic looking for treatment, as the scars caused significant psychological distress. We decided for a combination treatment with Erbium:glass 1540 nm non-ablative laser and 755 nm Alexandrite picosecond laser. After 16 weeks of starting treatment, significant improvement was observed, with complete resolution of the hyperpigmentation and overall improvement in the atrophic scar. No complications occurred during the treatment period. This strategy may be an effective and safe option to treat these lesions, which may be increasingly found in young individuals after COVID-19 disease or SARS-CoV-2 vaccination, even in darker skin phototypes.
Assuntos
COVID-19 , Herpes Zoster , Hiperpigmentação , Lasers de Estado Sólido , Feminino , Humanos , Adulto , Cicatriz/etiologia , Cicatriz/patologia , COVID-19/complicações , Vacinas contra COVID-19 , Resultado do Tratamento , SARS-CoV-2 , Lasers de Estado Sólido/uso terapêutico , Hiperpigmentação/complicações , Herpes Zoster/complicaçõesRESUMO
Colorectal cancer is the second leading cause of cancer-related mortality. Many current therapies rely on chemotherapeutic agents with poor specificity for tumor cells. The clinical success of cisplatin has prompted the research and design of a huge number of metal-based complexes as potential chemotherapeutic agents. In this study, two zinc(II) complexes, [ZnL2] and [ZnL(AcO)], where AcO is acetate and L is an organic compound combining 8-hydroxyquinoline and a benzothiazole moiety, were developed and characterized. Analytical and spectroscopic studies, namely, NMR, FTIR, and UV-Vis allowed us to establish the complexes' structures, demonstrating the ligand-binding versatility: tetradentate in [ZnL(AcO)] and bidentate in [ZnL2]. Complexes were screened in vitro using murine and human colon cancer cells cultured in 2D and 3D settings. In 2D cells, the IC50 values were <22 µM, while in 3D settings, much higher concentrations were required. [ZnL(AcO)] displayed more suitable antiproliferative properties than [ZnL2] and was chosen for further studies. Moreover, based on the weak selectivity of the zinc-based complex towards cancer cell lines in comparison to the non-tumorigenic cell line, its incorporation in long-blood-circulating liposomes was performed, aiming to improve its targetability. The resultant optimized liposomal nanoformulation presented an I.E. of 76% with a mean size under 130 nm and a neutral surface charge and released the metal complex in a pH-dependent manner. The antiproliferative properties of [ZnL(AcO)] were maintained after liposomal incorporation. Preliminary safety assays were carried out through hemolytic activity that never surpassed 2% for the free and liposomal forms of [ZnL(AcO)]. Finally, in a syngeneic murine colon cancer mouse model, while free [ZnL(AcO)] was not able to impair tumor progression, the respective liposomal nanoformulation was able to reduce the relative tumor volume in the same manner as the positive control 5-fluorouracil but, most importantly, using a dosage that was 3-fold lower. Overall, our results show that liposomes were able to solve the solubility issues of the new metal-based complex and target it to tumor sites.
Assuntos
Antineoplásicos , Neoplasias do Colo , Complexos de Coordenação , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/uso terapêutico , Lipossomos , Camundongos , Zinco/químicaRESUMO
Burkholderia cepacia (formerly Pseudomonas cepacia) was once thought to be a single bacterial species but has expanded to the Burkholderia cepacia complex (Bcc), comprising 24 closely related opportunistic pathogenic species. These bacteria have a widespread environmental distribution, an extraordinary metabolic versatility, a complex genome with three chromosomes, and a high capacity for rapid mutation and adaptation. Additionally, they present an inherent resistance to antibiotics and antiseptics, as well as the abilities to survive under nutrient-limited conditions and to metabolize the organic matter present in oligotrophic aquatic environments, even using certain antimicrobials as carbon sources. These traits constitute the reason that Bcc bacteria are considered feared contaminants of aqueous pharmaceutical and personal care products and the frequent reason behind nonsterile product recalls. Contamination with Bcc has caused numerous nosocomial outbreaks in health care facilities, presenting a health threat, particularly for patients with cystic fibrosis and chronic granulomatous disease and for immunocompromised individuals. This review addresses the role of Bcc bacteria as a potential public health problem, the mechanisms behind their success as contaminants of pharmaceutical products, particularly in the presence of biocides, the difficulties encountered in their detection, and the preventive measures applied during manufacturing processes to control contamination with these objectionable microorganisms. A summary of Bcc-related outbreaks in different clinical settings, due to contamination of diverse types of pharmaceutical products, is provided.
Assuntos
Complexo Burkholderia cepacia/fisiologia , Contaminação de Medicamentos , Microbiologia da Água , Infecções por Burkholderia/microbiologia , Infecção Hospitalar/microbiologia , Surtos de Doenças , Farmacorresistência Bacteriana Múltipla , Humanos , Infecções Oportunistas/microbiologiaRESUMO
Numerous genomes are sequenced and made available to the community through the NCBI portal. However, and, unlike what happens for gene function annotation, annotation of promoter sequences and the underlying prediction of regulatory associations is mostly unavailable, severely limiting the ability to interpret genome sequences in a functional genomics perspective. Here we present an approach where one can download a genome of interest from NCBI in the GenBank Flat File (.gbff) format and, with a minimum set of commands, have all the information parsed, organized and made available through the platform web interface. Also, the new genomes are compared with a given genome of reference in search of homologous genes, shared regulatory elements and predicted transcription associations. We present this approach within the context of Community YEASTRACT of the YEASTRACT + portal, thus benefiting from immediate access to all the comparative genomics queries offered in the YEASTRACT + portal. Besides the yeast community, other communities can install the platform independently, without any constraints. In this work, we exemplify the usefulness of the presented tool, within Community YEASTRACT, in constructing a dedicated database and analysing the genome of the highly promising oleaginous red yeast species Rhodotorula toruloides currently poorly studied at the genome and transcriptome levels and with limited genome editing tools. Regulatory prediction is based on the conservation of promoter sequences and available regulatory networks. The case-study examined is focused on the Haa1 transcription factor-a key regulator of yeast resistance to acetic acid, an important inhibitor of industrial bioconversion of lignocellulosic hydrolysates. The new tool described here led to the prediction of a RtHaa1 regulon with expected impact in the optimization of R. toruloides robustness for lignocellulosic and pectin-rich residue biorefinery processes.
Assuntos
Regulon , Leveduras , Anotação de Sequência Molecular , Rhodotorula , Fatores de Transcrição , Leveduras/genéticaRESUMO
Among the mechanisms by which yeast overcomes multiple stresses is the expression of genes encoding ATP-binding cassette (ABC) transporters required for resistance to a wide range of toxic compounds. These substrates may include weak acids, alcohols, agricultural pesticides, polyamines, metal cations, as in the case of Pdr18. This pleotropic drug resistance transporter was previously proposed to transport ergosterol at the plasma membrane (PM) level contributing to the maintenance of PM lipid organization and reduced diffusional permeation induced by lipophilic compounds. The present work reports a novel phenotype associated with the putative drug/xenobiotic-efflux-pump transporter Pdr18: the resistance to heat shock and to long-term growth at supra-optimal temperatures. Cultivation at 40°C was demonstrated to lead to higher PM permeabilization of a pdr18Δ cell population with the PDR18 gene deleted compared with the parental strain population, as indicated by flow cytometry analysis of propidium iodide stained cells. Cells of pdr18Δ grown at 40°C also exhibited increased transcription levels from genes of the ergosterol biosynthetic pathway, compared with parental cells. However, this adaptive response at 40°C was not enough to maintain PM physiological ergosterol levels in the population lacking the Pdr18 transporter and free ergosterol precursors accumulate in the deletion mutant cells.
Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Membrana Celular/metabolismo , Ergosterol/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Transporte Biológico , Membrana Celular/química , Membrana Celular/genética , Temperatura Alta , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , TermotolerânciaRESUMO
Responding to the recent interest of the yeast research community in non-Saccharomyces cerevisiae species of biotechnological relevance, the N.C.Yeastract (http://yeastract-plus.org/ncyeastract/) was associated to YEASTRACT + (http://yeastract-plus.org/). The YEASTRACT + portal is a curated repository of known regulatory associations between transcription factors (TFs) and target genes in yeasts. N.C.Yeastract gathers all published regulatory associations and TF-binding sites for Komagataellaphaffii (formerly Pichia pastoris), the oleaginous yeast Yarrowia lipolytica, the lactose fermenting species Kluyveromyces lactis and Kluyveromyces marxianus, and the remarkably weak acid-tolerant food spoilage yeast Zygosaccharomyces bailii. The objective of this review paper is to advertise the update of the existing information since the release of N.C.Yeastract in 2019, and to raise awareness in the community about its potential to help the day-to-day work on these species, exploring all the information available in the global YEASTRACT + portal. Using simple and widely used examples, a guided exploitation is offered for several tools: (i) inference of orthologous genes; (ii) search for putative TF binding sites and (iii) inter-species comparison of transcription regulatory networks and prediction of TF-regulated networks based on documented regulatory associations available in YEASTRACT + for well-studied species. The usage potentialities of the new CommunityYeastract platform by the yeast community are also discussed.
Assuntos
Regulação Fúngica da Expressão Gênica , Yarrowia , Bases de Dados Genéticas , Genômica , Saccharomyces cerevisiae , Leveduras/genéticaRESUMO
The reaction of potentially N,N,O-tridentate Schiff base ligands, Cl-LH, Br-LH, BrCl-LH and H-LH, with [VIVO(acac)2] in 2:1 ratio in methanol gave the corresponding mononuclear and dinuclear oxidovanadium(IV) complexes, VO(Cl-L)2 (1), VO(Br-L)2 (2), [(BrCl-L)2(H2O)V(µ-O)VO(BrCl-L)2] (3) and [(H-L)2(H2O)V(µ -O)VO(H-L)2] (4), in good yields. The ligands and complexes were fully characterized by elemental analysis and FT-IR spectroscopy. The ligands were also characterized by 1H NMR spectroscopy. The oxidation state of V(IV)O with d1 configuration in all synthesized complexes was confirmed by EPR. Moreover, the structures of 2 and 3 were determined by X-ray diffraction (XRD) analysis which revealed them as mono- and dinuclear vanadium(IV) complexes, respectively, with the ligands coordinated as bidentate chelates. The structure of 3 represents the first example of dinuclear V(IV) complex with O â VIV = O â VIV = O core (Cambridge Structural Database (CSD)â, version 5.42, update of May 2021). The cytotoxicity of ligands and complexes was evaluated towards ovarian (A2780), breast (MCF7) and prostate (PC3) cancer cells at 48 h. While ligands showed modest IC50 values (>42 µM), all complexes turned out to be effective in the range 3.9-17.2 µM. In particular, A2780 and MCF7 cell lines were the most sensitive to the newly synthesized V(IV)O complexes.
Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Bases de Schiff/farmacologia , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/síntese química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ligantes , Estrutura Molecular , Bases de Schiff/síntese química , Vanádio/químicaRESUMO
BACKGROUND: In 2005, the Portuguese government launched a Primary Care reform that aimed to reinforce continuity of care. After a promising start, the reform is still incomplete and continuity has been compromised by the lack of General Practice doctors. OBJECTIVE: This study evaluates public preferences for relational continuity of care alongside other attributes of Primary Care services in Portugal. METHODS: We use a discrete choice experiment (DCE) to evaluate preferences and estimate the population's willingness to pay (WTP) for Primary Care attributes. We use a sequential, mixed-methods approach to develop a D-efficient fractional factorial design for the DCE. Five attributes were included in the DCE and there were 32 DCE choice sets. The data collection was conducted in 2014 and the final sample had 517 respondents. A random parameters multinomial logit was used to analyse the data. RESULTS: We find that respondents value relational continuity of care, but that the current focus of the Portuguese NHS on relational continuity at the expense of other attributes is too simplistic. CONCLUSIONS: Relational continuity should be part of a broader policy that emphasizes person-centred care and considers the preferences of patients for Primary Care attributes.