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1.
BMC Public Health ; 23(1): 2370, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-38031084

RESUMO

BACKGROUND: The discussion about breast cancer (BC) causation continues to be surrounded by a number of myths and misbeliefs. If efforts are misdirected towards reducing risk from false mythical causes, individuals might be less likely to consider and adopt risk-reducing behaviors for evidence-based BC causes. This national study aimed to assess the awareness of BC causation myths and misbeliefs among Palestinian women, and examine the factors associated with having good awareness. METHODS: This national cross-sectional study recruited adult women from government hospitals, primary healthcare centers, and public spaces in 11 governorates in Palestine. A modified version of the Cancer Awareness Measure-Mythical Causes Scale was used to collect data. The level of awareness of BC causation myths was determined based on the number of myths recognized to be incorrect: poor (0-5), fair (6-10), or good (11-15). RESULTS: A total of 5,257 questionnaires were included. Only 269 participants (5.1%) demonstrated good awareness (i.e., recognizing more than 10 out of 15 BC mythical causes). There were no notable differences in displaying good awareness between the main areas of Palestine, the Gaza Strip and the West Bank and Jerusalem (5.1% vs. 5.1%). Having chronic disease as well as visiting hospitals and primary healthcare centers were associated with a decrease in the likelihood of displaying good awareness. Myths related to food were less frequently recognized as incorrect than food-unrelated myths. 'Eating burnt food' was the most recognized food-related myth (n = 1414, 26.9%), while 'eating food containing additives' was the least recognized (n = 599, 11.4%). 'Having a physical trauma' was the most recognized food-unrelated myth (n = 2795, 53.2%), whereas the least recognized was 'wearing tight bra' (n = 1018, 19.4%). CONCLUSIONS: A very small proportion of Palestinian women could recognize 10 or more myths around BC causation. There is a substantial need to include clear information about BC causation in future educational interventions besides focusing on BC screening, signs and symptoms, and risk factors.


Assuntos
Neoplasias da Mama , Adulto , Humanos , Feminino , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etiologia , Neoplasias da Mama/diagnóstico , Estudos Transversais , Árabes , Oriente Médio/epidemiologia , Inquéritos e Questionários , Conhecimentos, Atitudes e Prática em Saúde
2.
Proc Natl Acad Sci U S A ; 117(45): 27954-27961, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33106428

RESUMO

Toxicity from the external presence or internal production of compounds can reduce the growth and viability of microbial cell factories and compromise productivity. Aromatic compounds are generally toxic for microorganisms, which makes their production in microbial hosts challenging. Here we use adaptive laboratory evolution to generate Saccharomyces cerevisiae mutants tolerant to two aromatic acids, coumaric acid and ferulic acid. The evolution experiments were performed at low pH (3.5) to reproduce conditions typical of industrial processes. Mutant strains tolerant to levels of aromatic acids near the solubility limit were then analyzed by whole genome sequencing, which revealed prevalent point mutations in a transcriptional activator (Aro80) that is responsible for regulating the use of aromatic amino acids as the nitrogen source. Among the genes regulated by Aro80, ESBP6 was found to be responsible for increasing tolerance to aromatic acids by exporting them out of the cell. Further examination of the native function of Esbp6 revealed that this transporter can excrete fusel acids (byproducts of aromatic amino acid catabolism) and this role is shared with at least one additional transporter native to S. cerevisiae (Pdr12). Besides conferring tolerance to aromatic acids, ESBP6 overexpression was also shown to significantly improve the secretion in coumaric acid production strains. Overall, we showed that regulating the activity of transporters is a major mechanism to improve tolerance to aromatic acids. These findings can be used to modulate the intracellular concentration of aromatic compounds to optimize the excretion of such products while keeping precursor molecules inside the cell.


Assuntos
Ácidos Cumáricos/metabolismo , Tolerância a Medicamentos/genética , Ácidos/metabolismo , Adaptação Fisiológica/genética , Aminoácidos Aromáticos/metabolismo , Aminoácidos Aromáticos/toxicidade , Ácidos Cumáricos/toxicidade , Evolução Molecular Direcionada , Tolerância a Medicamentos/fisiologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Sequenciamento Completo do Genoma/métodos
3.
Metab Eng ; 72: 376-390, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35598887

RESUMO

Membrane transport proteins are potential targets for medical and biotechnological applications. However, more than 30% of reported membrane transporter families are either poorly characterized or lack adequate functional annotation. Here, adaptive laboratory evolution was leveraged to identify membrane transporters for a set of four amino acids as well as specific mutations that modulate the activities of these transporters. Specifically, Escherichia coli was adaptively evolved under increasing concentrations of L-histidine, L-phenylalanine, L-threonine, and L-methionine separately with multiple replicate evolutions. Evolved populations and isolated clones displayed growth rates comparable to the unstressed ancestral strain at elevated concentrations (four-to six-fold increases) of the targeted amino acids. Whole genome sequencing of the evolved strains revealed a diverse number of key mutations, including SNPs, small deletions, and copy number variants targeting the transporters leuE for histidine, yddG for phenylalanine, yedA for methionine, and brnQ and rhtC for threonine. Reverse engineering of the mutations in the ancestral strain established mutation causality of the specific mutations for the tolerant phenotypes. The functional roles of yedA and brnQ in the transport of methionine and threonine, respectively, are novel assignments and their functional roles were validated using a flow cytometry cellular accumulation assay. To demonstrate how the identified transporters can be leveraged for production, an L-phenylalanine overproduction strain was shown to be a superior producer when the identified yddG exporter was overexpressed. Overall, the results revealed the striking efficiency of laboratory evolution to identify transporters and specific mutational mechanisms to modulate their activities, thereby demonstrating promising applicability in transporter discovery efforts and strain engineering.


Assuntos
Sistemas de Transporte de Aminoácidos Neutros , Proteínas de Escherichia coli , Sistemas de Transporte de Aminoácidos Neutros/genética , Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Aminoácidos/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Proteínas de Membrana Transportadoras/genética , Metionina/genética , Fenilalanina/genética , Treonina/genética
4.
Metab Eng ; 56: 130-141, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31550508

RESUMO

Improving the growth phenotypes of microbes in high product concentrations is an essential design objective in the development of robust cell factories. However, the limited knowledge regarding tolerance mechanisms makes rational design of such traits complicated. Here, adaptive laboratory evolution was used to explore the tolerance mechanisms that Saccharomyces cerevisiae can evolve in the presence of inhibiting concentrations of three dicarboxylic acids: glutaric acid, adipic acid and pimelic acid. Whole-genome sequencing of tolerant mutants enabled the discovery of the genetic changes behind tolerance and most mutations could be linked to the up-regulation of multidrug resistance transporters. The amplification of QDR3, in particular, was shown to confer tolerance not only to the three dicarboxylic acids investigated, but also towards muconic acid and glutaconic acid. In addition to increased acid tolerance, QDR3 overexpression also improved the production of muconic acid in the context of a strain engineered for producing this compound.


Assuntos
Ácidos Dicarboxílicos/farmacologia , Evolução Molecular Direcionada , Regulação Fúngica da Expressão Gênica , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/biossíntese , Proteínas de Saccharomyces cerevisiae/genética
5.
Membranes (Basel) ; 14(3)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38535289

RESUMO

Transport systems play a pivotal role in bacterial physiology and represent potential targets for medical and biotechnological applications. However, even in well-studied organisms like Escherichia coli, a notable proportion of transporters, exceeding as many as 30%, remain classified as orphans due to their lack of known substrates. This study leveraged high-resolution LC-MS-based untargeted metabolomics to identify candidate substrates for these orphan transporters. Human serum, including a diverse array of biologically relevant molecules, served as an unbiased source for substrate exposure. The analysis encompassed 26 paired transporter mutant contrasts (i.e., knockout vs. overexpression), compared with the wild type, revealing distinct patterns of substrate uptake and excretion across various mutants. The convergence of candidate substrates across mutant scenarios provided robust validation, shedding light on novel transporter-substrate relationships, including those involving yeaV, hsrA, ydjE, and yddA. Furthermore, several substrates were contingent upon the specific mutants employed. This investigation underscores the utility of untargeted metabolomics for substrate identification in the absence of prior knowledge and lays the groundwork for subsequent validation experiments, holding significant implications for both medical and biotechnological advancements.

6.
Membranes (Basel) ; 12(12)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36557171

RESUMO

Multidrug transporters (MDTs) are major contributors to microbial drug resistance and are further utilized for improving host phenotypes in biotechnological applications. Therefore, the identification of these MDTs and the understanding of their mechanisms of action in vivo are of great importance. However, their promiscuity and functional redundancy represent a major challenge towards their identification. Here, a multistep tolerance adaptive laboratory evolution (TALE) approach was leveraged to achieve this goal. Specifically, a wild-type E. coli K-12-MG1655 and its cognate knockout individual mutants ΔemrE, ΔtolC, and ΔacrB were evolved separately under increasing concentrations of two lipophilic cations, tetraphenylphosphonium (TPP+), and methyltriphenylphosphonium (MTPP+). The evolved strains showed a significant increase in MIC values of both cations and an apparent cross-cation resistance. Sequencing of all evolved mutants highlighted diverse mutational mechanisms that affect the activity of nine MDTs including acrB, mdtK, mdfA, acrE, emrD, tolC, acrA, mdtL, and mdtP. Besides regulatory mutations, several structural mutations were recognized in the proximal binding domain of acrB and the permeation pathways of both mdtK and mdfA. These details can aid in the rational design of MDT inhibitors to efficiently combat efflux-based drug resistance. Additionally, the TALE approach can be scaled to different microbes and molecules of medical and biotechnological relevance.

7.
JCO Glob Oncol ; 8: e2200087, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36508704

RESUMO

PURPOSE: This study aimed to assess awareness of Palestinian women about breast cancer (BC) age-related and lifetime risks and its risk factors and to identify factors associated with good awareness. MATERIALS AND METHODS: Adult women were recruited from government hospitals, primary health care centers, and public spaces in 11 governorates in Palestine. Recognition of 14 BC risk factors was assessed using a translated-into-Arabic version of the validated BC awareness measure. The level of BC risk factor awareness was determined on the basis of the number of risk factors recognized: poor (0-4), fair (5-9), and good (10-14). RESULTS: Of 6,269 potential participants approached, 5,434 agreed and completed the questionnaire (response rate = 86.7%). A total of 5,257 questionnaires were included: 2,706 from the West Bank and Jerusalem and 2,551 from the Gaza Strip. Only 173 participants (3.3%) recognized the age-related risk of BC. More than one quarter (n = 1,465; 27.9%) recognized the lifetime risk of BC. The most recognized modifiable risk factor was not breastfeeding (n = 4,937; 93.9%), whereas the least recognized was having children later on in life or not at all (n = 1,755; 33.4%). The most recognized nonmodifiable risk factor was radiation exposure (n = 4,579; 87.1%), whereas the least recognized was starting the periods at an early age (n = 1,030; 19.6%). In total, 2,024 participants (38.4%) demonstrated good BC risk factor awareness. Participants from the Gaza Strip had a higher likelihood than participants from the West Bank and Jerusalem to have good awareness (42.0% v 35.2%). Age ≥ 40 years, postsecondary education, and visiting hospitals and primary health care centers were all associated with an increase in the likelihood of having good BC risk factor awareness. CONCLUSION: The awareness of BC risk factors was suboptimal. These findings highlight the need for implementing health education programs combined with consistent use of ad hoc opportunities to raise awareness by health care providers.


Assuntos
Neoplasias da Mama , Adulto , Criança , Humanos , Feminino , Neoplasias da Mama/epidemiologia , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Árabes , Fatores de Risco
8.
Bioresour Technol ; 333: 125171, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33894448

RESUMO

Using lignocellulosic biomass hydrolysate for the production of microbial lipids and carotenoids is still a challenge due to the poor tolerance of oleaginous yeasts to the inhibitors generated during biomass pretreatment. In this study, a strategy of adaptive laboratory evolution in hydrolysate-based medium was developed to improve the tolerance of Rhodosporidium toruloides to inhibitors present in biomass hydrolysate. The evolved strains presented better performance to grow in hydrolysate medium, with a significant reduction in their lag phases, and improved ability to accumulate lipids and produce carotenoids when compared to the wild-type starting strain. In the best cases, the lag phase was reduced by 72 h and resulted in lipid accumulation of 27.89 ± 0.80% (dry cell weight) and carotenoid production of 14.09 ± 0.12 mg/g (dry cell weight). Whole genome sequencing analysis indicated that the wild-type strain naturally contained tolerance-related genes, which provided a background that allowed the strain to evolve in biomass-derived inhibitors.


Assuntos
Variação Genética , Laboratórios , Biomassa , Lignina , Rhodotorula
9.
Metab Eng Commun ; 11: e00143, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32963959

RESUMO

Pseudomonas putida KT2440 is a promising bacterial chassis for the conversion of lignin-derived aromatic compound mixtures to biofuels and bioproducts. Despite the inherent robustness of this strain, further improvements to aromatic catabolism and toxicity tolerance of P. putida will be required to achieve industrial relevance. Here, tolerance adaptive laboratory evolution (TALE) was employed with increasing concentrations of the hydroxycinnamic acids p-coumaric acid (pCA) and ferulic acid (FA) individually and in combination (pCA â€‹+ â€‹FA). The TALE experiments led to evolved P. putida strains with increased tolerance to the targeted acids as compared to wild type. Specifically, a 37 â€‹h decrease in lag phase in 20 â€‹g/L pCA and a 2.4-fold increase in growth rate in 30 â€‹g/L FA was observed. Whole genome sequencing of intermediate and endpoint evolved P. putida populations revealed several expected and non-intuitive genetic targets underlying these aromatic catabolic and toxicity tolerance enhancements. PP_3350 and ttgB were among the most frequently mutated genes, and the beneficial contributions of these mutations were verified via gene knockouts. Deletion of PP_3350, encoding a hypothetical protein, recapitulated improved toxicity tolerance to high concentrations of pCA, but not an improved growth rate in high concentrations of FA. Deletion of ttgB, part of the TtgABC efflux pump, severely inhibited growth in pCA â€‹+ â€‹FA TALE-derived strains but did not affect growth in pCA â€‹+ â€‹FA in a wild type background, suggesting epistatic interactions. Genes involved in flagellar movement and transcriptional regulation were often mutated in the TALE experiments on multiple substrates, reinforcing ideas of a minimal and deregulated cell as optimal for domesticated growth. Overall, this work demonstrates increased tolerance towards and growth rate at the expense of hydroxycinnamic acids and presents new targets for improving P. putida for microbial lignin valorization.

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