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1.
PLoS One ; 18(9): e0287246, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37751450

RESUMEN

Sesame is an important oilseed crop cultivated in Ethiopia as a cash crop for small holder farmers. However, low yield is one of the main constraints of its cultivation. Boosting and sustaining production of sesame is thus timely to achieve the global oil demand. This study was, therefore, aimed at identifying mutant genotypes targeted to produce better agronomic traits of M2 lines on fourteen Ethiopian sesame genotypes through seed treatment with chemical mutagens. EMS was used as a chemical mutagen to treat the fourteen sesame genotypes. Quantitative and qualitative data were recorded and analyzed using analysis of variance with GenStat 16 software. Post-ANOVA mean comparisons were made using Duncan's Multiple Range Test (p≤ 0.01). Statistically significant phenotypic changes were observed in both quantitative and qualitative agronomic traits of the M2 lines. All mutant genotypes generated by EMS treatment showed a highly significant variation for the measured quantitative traits, except for the traits LBL and LTL. On the other hand, EMS-treated genotypes showed a significant change for the qualitative traits, except for PGT, BP, SSCS, LC, LH and LA traits. Mutated Baha Necho, Setit 3, and Zeri Tesfay showed the most promising changes in desirable agronomic traits. To the best of our knowledge, this study represents the first report on the treatment of sesame seeds with EMS to generate desirable agronomic traits in Ethiopian sesame genotypes. These findings would deliver an insight into the genetic characteristics and variability of important sesame agronomic traits. Besides, the findings set up a foundation for future genomic studies in sesame agronomic traits, which would serve as genetic resources for sesame improvement.


Asunto(s)
Sesamum , Sesamum/genética , Metanosulfonato de Etilo/farmacología , Fenotipo , Genotipo , Metano
2.
J Biosci Bioeng ; 136(4): 270-277, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37544800

RESUMEN

The yeast Saccharomyces cerevisiae able to tolerate lignocellulose-derived inhibitors like furfural. Yeast strain performance tolerance has been measured by the length of the lag phase for cell growth in response to the furfural inhibitor challenge. The aims of this work were to obtain RDS1 yeast tolerant strain against furfural through overexpression using a method of in vivo homologous recombination. Here, we report that the overexpressing RDS1 recovered more rapidly and displayed a lag phase at about 12 h than its parental strain. Overexpressing RDS1 strain encodes a novel aldehyde reductase with catalytic function for reduction of furfural with NAD(P)H as the co-factor. It displayed the highest specific activity (24.8 U/mg) for furfural reduction using NADH as a cofactor. Fluorescence microscopy revealed improved accumulation of reactive oxygen species resistance to the damaging effects of inhibitor in contrast to the parental. Comparative transcriptomics revealed key genes potentially associated with stress responses to the furfural inhibitor, including specific and multiple functions involving defensive reduction-oxidation reaction process and cell wall response. A significant change in expression level of log2 (fold change >1) was displayed for RDS1 gene in the recombinant strain, which demonstrated that the introduction of RDS1 overexpression promoted the expression level. Such signature expressions differentiated tolerance phenotypes of RDS1 from the innate stress response of its parental strain. Overexpression of the RDS1 gene involving diversified functional categories is accountable for stress tolerance in yeast S. cerevisiae to survive and adapt the furfural during the lag phase.


Asunto(s)
Furaldehído , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Furaldehído/farmacología , NAD/metabolismo , Fenotipo , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transcriptoma
3.
Pol J Microbiol ; 72(2): 177-186, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37314359

RESUMEN

Lignocellulosic biomass is still considered a feasible source of bioethanol production. Saccharomyces cerevisiae can adapt to detoxify lignocellulose-derived inhibitors, including furfural. Tolerance of strain performance has been measured by the extent of the lag phase for cell proliferation following the furfural inhibitor challenge. The purpose of this work was to obtain a tolerant yeast strain against furfural through overexpression of YPR015C using the in vivo homologous recombination method. The physiological observation of the overexpressing yeast strain showed that it was more resistant to furfural than its parental strain. Fluorescence microscopy revealed improved enzyme reductase activity and accumulation of oxygen reactive species due to the harmful effects of furfural inhibitor in contrast to its parental strain. Comparative transcriptomic analysis revealed 79 genes potentially involved in amino acid biosynthesis, oxidative stress, cell wall response, heat shock protein, and mitochondrial-associated protein for the YPR015C overexpressing strain associated with stress responses to furfural at the late stage of lag phase growth. Both up- and down-regulated genes involved in diversified functional categories were accountable for tolerance in yeast to survive and adapt to the furfural stress in a time course study during the lag phase growth. This study enlarges our perceptions comprehensively about the physiological and molecular mechanisms implicated in the YPR015C overexpressing strain's tolerance under furfural stress. Construction illustration of the recombinant plasmid. a) pUG6-TEF1p-YPR015C, b) integration diagram of the recombinant plasmid pUG6-TEF1p-YPR into the chromosomal DNA of Saccharomyces cerevisiae.


Asunto(s)
Furaldehído , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Furaldehído/farmacología , Biomasa , Pared Celular , Perfilación de la Expresión Génica
4.
Int J Nurs Stud Adv ; 5: 100116, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38746557

RESUMEN

Background: Nurses provide 90% of health care worldwide, yet little is known of the experiences of nurses and midwives in policy development in low- and middle-income countries (LMICs). Objective: To identify, appraise and synthesize the qualitative evidence on the experiences of nurses' and midwives' involvement in policy development LMICs. Design: A qualitative systematic review using modified Joanna Briggs Institute (JBI) methodology. Setting: Low and middle-income countries. Participants: Nurses' and midwives' involved in policy development, implementation, and/or evaluation. Methods: A systematic search was undertaken across nine databases to retrieve published studies in English between inception and April of 2021. Screening, critical appraisal, and data extraction was undertaken by two independent reviewers. Results: Ten articles met inclusion criteria. All studies were published between 2000 to 2021 from a variety of LMICs. The studies were medium to high quality (70-100% critical appraisal scores). Four major themes were identified related to policy development: 1) Marginal representation of nurses; 2) Determinants of nurses' involvement (including at the individual, organization, and systematic level); 3) Leadership as a pathway to involvement; 4) Promoting nurses' involvement. Conclusion: All studies demonstrated that nurses and nurse midwives continue to be minimally involved in policy development. Findings reveal reasons for nurses' limited involvement and strategies to foster sustained engagement of nurses in policy development in LMICs. To enhance their involvement in policy development in LMICs, change is needed at multiple levels. Systemic power relations need to be reconstructed to facilitate more collaborative interdisciplinary practices with nurses co-leading and co-developing health care policies.

5.
J Public Health Res ; 11(2)2021 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-34967533

RESUMEN

The challenges of identifying and eliminating racial disparities regarding the exposure, transmission, prevention, and treatment of communicable diseases within the healthcare system have been a mounting concern since the COVID-19 pandemic began. The African, Caribbean, and Black (ACB) populations in Canada represent a fast-expanding and underprivileged community, which have been previously found to have higher susceptibility to communicable diseases and lower sensitivity to intervention measures. Currently, there is insufficient evidence to adequately identify racial patterns in the prevalence and healthcare utilization among the ACB population within the context of the ongoing pandemic. Our proposed study will explore the association between the social determinants of health (SDH) and COVID-19 health outcomes in ACB populations in high-income countries (UK, US, Australia). We will explore the literary evidence through a systematic review (SR) of COVID-19 literature covering the period between December 2019 and October 2020. The objectives include investigating the effect of SDH on the ACB populations' risk to COVID-19 health outcomes, including COVID-19 infection incidence, severity of disease, hospitalization, mortality and barriers to the treatment and management of COVID-19 for Black people in Canada. In addition, this project aims to investigate the effect of COVID-19 on ACB communities in Ontario by examining the challenges that front-line healthcare workers and administrators have during this pandemic as it pertains to service provisions to ACB communities. A systematic review of original and review studies will be conducted based on the publications on eleven databases (MEDLINE, Web of Science, Cochrane Library, CINAHL, NHS EDD, Global Health, PsychInfo, PubMed, Scopus, Proquest, and Taylor and Francis Online Journals) published between December 2019 to October 2020. Primary outcomes will include the rate of COVID-19 infection. The systematic review will include a meta-analysis of available quantitative data, as well as a narrative synthesis of qualitative studies. This systematic review will be among the first to report racial disparities in COVID-19 infection among the ACB population in Canada. Through synthesizing population data regarding the risk factors on various levels, the findings from this systematic review will provide recommendations for future research and evidence for clinical practitioners and social workers. Overall, a better understanding of the nature and consequences of racial disparities during the pandemic will provide policy directions for effective interventions and resilience-building in the post-pandemic era.

6.
J Biosci Bioeng ; 131(1): 39-46, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32967812

RESUMEN

Aldehydes are the main inhibitors generated during the pretreatment of lignocellulosic biomass, which can inhibit cell growth and disturb subsequent fermentation. Saccharomyces cerevisiae has the intrinsic ability to in situ detoxify aldehydes to their less toxic or nontoxic alcohols by numerous aldehyde dehydrogenases/reductases during the lag phase. Herein, we report that an uncharacterized open reading frame YMR152W from S. cerevisiae encodes a novel aldehyde reductase with catalytic functions for reduction of at least six aldehydes, including two furan aldehydes (furfural and 5-hydroxymethylfurfural), three aliphatic aldehydes (acetaldehyde, glycolaldehyde, and 3-methylbutanal), and an aromatic aldehyde (benzaldehyde) with NADH or NADPH as the co-factor. Particularly, Ymr152wp displayed the highest specific activity (190.86 U/mg), and the best catalytic rate constant (Kcat), catalytic efficiency (Kcat/Km), and affinity (Km) when acetaldehyde was used as the substrate with NADH as the co-factor. The optimum pH of Ymr152wp is acidic (pH 5.0-6.0), but this enzyme is more stable in alkaline conditions (pH 8.0). Metal ions, chemical protective additives, salts, and substrates could stimulate or inhibit enzyme activities of Ymr152wp in varying degrees. Ymr152wp was classified into the quinone oxidoreductase (QOR) subfamily of the medium-chain dehydrogenase/reductase (MDR) family based on the results of amino acid sequence analysis and phylogenetic analysis. Although Ymr152wp was grouped into the QOR family, no quinone reductase activity was observed using typical quinones (9,10-phenanthrenequinone, 1,2-naphthoquinone, and p-benzoquinone) as the substrates. This study provides guidelines for exploring more uncharacterized aldehyde reductases in S. cerevisiae for in situ detoxification of aldehyde inhibitors derived from lignocellulosic hydrolysis.


Asunto(s)
Aldehído Reductasa/metabolismo , Aldehídos/metabolismo , Biomasa , Lignina/química , Saccharomyces cerevisiae/enzimología , Aldehído Reductasa/genética , Aldehídos/aislamiento & purificación , Filogenia , Saccharomyces cerevisiae/genética
7.
Appl Microbiol Biotechnol ; 104(15): 6679-6692, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32556414

RESUMEN

At least 24 aldehyde reductases from Saccharomyces cerevisiae have been characterized and most function in in situ detoxification of lignocellulosic aldehyde inhibitors, but none is classified into the polyol dehydrogenase (PDH) subfamily of the medium-chain dehydrogenase/reductase (MDR) superfamily. This study confirmed that two (2R,3R)-2,3-butanediol dehydrogenases (BDHs) from industrial (denoted Y)/laboratory (denoted B) strains of S. cerevisiae, Bdh1p(Y)/Bdh1p(B) and Bdh2p(Y)/Bdh2p(B), were members of the PDH subfamily with an NAD(P)H binding domain and a catalytic zinc binding domain, and exhibited reductive activities towards lignocellulosic aldehyde inhibitors, such as acetaldehyde, glycolaldehyde, and furfural. Especially, the highest enzyme activity towards acetaldehyde by Bdh2p(Y) was 117.95 U/mg with cofactor nicotinamide adenine dinucleotide reduced (NADH). Based on the comparative kinetic property analysis, Bdh2p(Y)/Bdh2p(B) possessed higher specific activity, substrate affinity, and catalytic efficiency towards glycolaldehyde than Bdh1p(Y)/Bdh1p(B). This was speculated to be related to their 49% sequence differences and five nonsynonymous substitutions (Ser41Thr, Glu173Gln, Ile270Leu, Ile316Met, and Gly317Cys) occurred in their conserved NAD(P)H binding domains. Compared with BDHs from a laboratory strain, Bdh1p(Y) and Bdh2p(Y) from an industrial strain displayed five nonsynonymous mutations (Thr12, Asn61, Glu168, Val222, and Ala235) and three nonsynonymous mutations (Ala34, Ile96, and Ala369), respectively. From a first analysis with selected aldehydes, their reductase activities were different from BDHs of laboratory strain, and their catalytic efficiency was higher towards glycolaldehyde and lower towards acetaldehyde. Comparative investigation of kinetic properties of BDHs from S. cerevisiae as aldehyde reductases provides a guideline for their practical applications in in situ detoxification of aldehyde inhibitors during lignocellulose bioconversion.Key Points• Two yeast BDHs have enzyme activities for reduction of aldehydes.• Overexpression of BDHs slightly improves yeast tolerance to acetaldehyde and glycolaldehyde.• Bdh1p and Bdh2p differ in enzyme kinetic properties.• BDHs from strains with different genetic backgrounds differ in enzyme kinetic properties.


Asunto(s)
Oxidorreductasas de Alcohol/metabolismo , Aldehídos/antagonistas & inhibidores , L-Iditol 2-Deshidrogenasa/metabolismo , Lignina/antagonistas & inhibidores , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimología , Acetaldehído/análogos & derivados , Acetaldehído/metabolismo , Oxidorreductasas de Alcohol/clasificación , Cinética , L-Iditol 2-Deshidrogenasa/clasificación , Lignina/metabolismo , Especificidad por Sustrato
8.
Front Microbiol ; 11: 544, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32373081

RESUMEN

Phenol is a ubiquitous pollutant and can contaminate natural water resources. Hence, the removal of phenol from wastewater is of significant importance. A series of biological methods were used to remove phenol based on the natural ability of microorganisms to degrade phenol, but the tolerance mechanism of phenol-degraded strains to phenol are not very clear. Morphological observation on Candida tropicalis showed that phenol caused the reactive oxygen species (ROS) accumulation, damaging the mitochondrial and the endoplasmic reticulum. On the basis of transcriptome data and cell wall susceptibility analysis, it was found that C. tropicalis prevented phenol-caused cell damage through improvement of cell wall resistance, maintenance of high-fidelity DNA replication, intracellular protein homeostasis, organelle integrity, and kept the intracellular phenol concentration at a low level through cell-wall remodeling and removal of excess phenol via MDR/MXR transporters. The knowledge obtained will promote the genetic modification of yeast strains in general to tolerate the high concentrations of phenol and improve their efficiency of phenol degradation.

9.
Appl Microbiol Biotechnol ; 103(14): 5699-5713, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31115629

RESUMEN

The aldehyde reductases from the short-chain dehydrogenase/reductase (SDR) family were identified as a series of critical enzymes for the improved tolerance of Saccharomyces cerevisiae to the aldehydes by catalyzing the detoxification reactions of aldehydes. Herein, we report that a novel aldehyde reductase Ykl107wp deduced from YKL107W from S. cerevisiae belongs to the classical SDR group and can catalyze the reduction reactions of acetaldehyde (AA), glycolaldehyde (GA), furfural (FF), formaldehyde (FA), and propionaldehyde (PA) but cannot reduce the six representative ketones. Ykl107wp displayed the best maximum velocity (Vmax), catalytic rate constant (Kcat), catalytic efficiency (Kcat/Km), and highest affinity (Km) to acetaldehyde. The optimum pH of Ykl107wp was 6.0 for the reduction of AA and 7.0 for the reduction of GA and FF, and the optimum temperatures were 40, 35, and 30 °C for the reduction of AA, GA, and FF, respectively. Ykl107wp for the reduction of AA was greatly affected by metal ions, chemical additives, and salts and showed poor thermal and pH stability, but its stability was slightly affected by a substrate. Ykl107wp was localized in endoplasmic reticulum and prevented the yeast cells from damage caused by furfural via the detoxification of furfural to furfural alcohol. This research provides guidelines for the study of uncharacterized classical SDR aldehyde reductases and exploration of their protective mechanisms on the corresponding organelles.


Asunto(s)
Acetaldehído/análogos & derivados , Acetaldehído/metabolismo , Aldehído Reductasa/metabolismo , Furaldehído/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimología , Aldehído Reductasa/genética , Catálisis , Inactivación Metabólica , Cinética , Proteínas de Saccharomyces cerevisiae/genética
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