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1.
Mar Drugs ; 21(4)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37103366

RESUMO

In this study, mycelia of eight recently described species of Halophytophthora and H. avicennae collected in Southern Portugal were analysed for lipids and fatty acids (FA) content to evaluate their possible use as alternative sources of FAs and understand how each species FAs profile relates to their phylogenetic position. All species had a low lipid percentage (0.06% in H. avicennae to 0.28% in H. frigida). Subclade 6b species contained more lipids. All species produced monounsaturated (MUFA), polyunsaturated (PUFA) and saturated (SFA) FAs, the latter being most abundant in all species. H. avicennae had the highest FA variety and was the only producer of γ-linolenic acid, while H. brevisporangia produced the lowest number of FAs. The best producer of arachidonic acid (ARA) and eicosapentaenoic acid (EPA) was H. thermoambigua with 3.89% and 9.09% of total FAs, respectively. In all species, palmitic acid (SFA) was most abundant and among the MUFAs produced oleic acid had the highest relative percentage. Principal component analysis (PCA) showed partial segregation of species by phylogenetic clade and subclade based on their FA profile. H. avicennae (Clade 4) differed from all other Clade 6 species due to the production of γ-linolenic and lauric acids. Our results disclosed interesting FA profiles in the tested species, adequate for energy (biodiesel), pharmaceutical and food industries (bioactive FAs). Despite the low amounts of lipids produced, this can be boosted by manipulating culture growth conditions. The observed interspecific variations in FA production provide preliminary insights into an evolutionary background of its production.


Assuntos
Ácidos Graxos , Ácido Oleico , Filogenia , Portugal , Ácido Palmítico
2.
Mol Ecol ; 30(20): 5164-5178, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34398981

RESUMO

Various hypotheses have been proposed regarding the origin of the plant pathogen Phytophthora cinnamomi. P. cinnamomi is a devastating, highly invasive soilborne pathogen associated with epidemics of agricultural, horticultural and forest plantations and native ecosystems worldwide. We conducted a phylogeographic analysis of populations of this pathogen sampled in Asia, Australia, Europe, southern and northern Africa, South America, and North America. Based on genotyping-by-sequencing, we observed the highest genotypic diversity in Taiwan and Vietnam, followed by Australia and South Africa. Mating type ratios were in equal proportions in Asia as expected for a sexual population. Simulations based on the index of association suggest a partially sexual, semi-clonal mode of reproduction for the Taiwanese and Vietnamese populations while populations outside of Asia are clonal. Ancestral area reconstruction provides new evidence supporting Taiwan as the ancestral area, given our sample, indicating that this region might be near or at the centre of origin for this pathogen as speculated previously. The Australian and South African populations appear to be a secondary centre of diversity following migration from Taiwan or Vietnam. Our work also identified two panglobal, clonal lineages PcG1-A2 and PcG2-A2 of A2 mating type found on all continents. Further surveys of natural forests across Southeast Asia are needed to definitively locate the actual centre of origin of this important plant pathogen.


Assuntos
Phytophthora , Austrália , Ecossistema , Especificidade de Hospedeiro , Filogeografia , Phytophthora/genética , Doenças das Plantas
3.
Front Microbiol ; 11: 1467, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760358

RESUMO

We investigated the incidence of RNA viruses in a collection of Halophytophthora spp. from estuarine ecosystems in southern Portugal. The first approach to detect the presence of viruses was based on the occurrence of dsRNA, typically considered as a viral molecule in plants and fungi. Two dsRNA-banding patterns (∼7 and 9 kb) were observed in seven of 73 Halophytophthora isolates tested (9.6%). Consequently, two dsRNA-hosting isolates were chosen to perform stranded RNA sequencing for de novo virus sequence assembly. A total of eight putative novel virus species with genomic affinities to members of the order Bunyavirales were detected and their full-length RdRp gene characterized by RACE. Based on the direct partial amplification of their RdRp gene by RT-PCR multiple viral infections occur in both isolates selected. Likewise, the screening of those viruses in the whole collection of Halophytophthora isolates showed that their occurrence is limited to one single Halophytophthora species. To our knowledge, this is the first report demonstrating the presence of negative (-) ssRNA viruses in marine oomycetes.

4.
IMA Fungus ; 8(2): 219-244, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29242773

RESUMO

During surveys of Phytophthora diversity in natural and semi-natural Fagaceae forests in Austria, Italy and Portugal, four new cryptic species were isolated from rhizosphere soil samples. Multigene phylogeny based on nuclear ITS, ß-tubulin and HSP90 and mitochondrial cox1 and NADH1 gene sequences demonstrated that two species, P. tyrrhenica and P. vulcanica spp. nov., belong to phylogenetic Clade 7a, while the other two species, P. castanetorum and P. tubulina spp. nov., clustered together with P. quercina forming a new clade, named here as Clade 12. All four new species are homothallic and have low optimum and maximum temperatures for growth and very slow growth rates at their respective optimum temperature. They differed from each other and from related species by a unique combination of morphological characters, cardinal temperatures, and growth rates. Pathogenicity of all Phytophthora species to the root system of their respective host species was demonstrated in soil infestation trials.

5.
Phytochemistry ; 131: 158-164, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27641672

RESUMO

To investigate bioactive compounds potentially involved in the biotic interactions exhibited by Phlomis purpurea (Lamiaceae) in rhizospheres infested with Phytophthora cinnamomi, the plant rhizome was chemically analysed. The nortriterpenoid (17S)-2α,3α,11α,23,24-pentahydroxy-19(18 â†’ 17)-abeo-28-norolean-12-en-18-one, was isolated and its structure was elucidated by comprehensive spectroscopic analysis, chiefly using 2D NMR experiments, and X-ray analysis. It was shown to be exuded by roots and to exhibit anti-Phytophthora and antitumor activities.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Phlomis/química , Phytophthora/efeitos dos fármacos , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/química , Células HeLa , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Portugal , Rizoma/química , Triterpenos/química
6.
Eurohealth (Lond) ; 22(2): 1-53, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-32336930

RESUMO

Inability to invest in and develop mortality information systems has been considered the single most critical failure in health information systems and there is a recognized urgent need to improve mortality statistics and cause of death information. Although there have been major developments in information technology with the potential to improve public health information systems, mortality data collection has largely remained unchanged in most countries, mainly due to legal and operational barriers. Electronic registration and certification of death certificates has the potential to improve the quality and timeliness of mortality statistics. The Mortality Information System in Portugal has, since 1950, been a paper-form death certification model. The Portuguese Directorate-General of Health recently implemented electronic death certification as the basis of a new mortality information system. A strategic multistep approach, defined by geographic areas of the country, was planned for implementation of the system. National implementation was completed in December of 2013 and 100% e-death certification was achieved beginning January 2014. This article reports the implementation process and describes the newly established mortality information system.

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