2,661 research outputs found
Analysis of intact prophages in genomes of paenibacillus larvae, an important pathogen for bees
Paenibacillus larvae is a highly contagious spore-forming bacteria, responsible for the American
Foulbrood (AFB) disease, lethal to honeybee brood. Integrated in bacterial genomes, prophages are
often able to provide new genes or to alter phenotypic characteristics of bacteria. The potential role
of prophages in the performance of P. larvae has been studied.
A total of 55 intact prophage genomes from 11 P. larvae strains were annotated and analysed. The
main focus was to infer the influence of their genes with some type of virulence trait (e.g.: toxins),
or functions such as antibiotic resistance, metabolic function, germination/sporulation or transporter
of nutrients, which could improve bacterial fitness. We also aimed at understanding if specific
traits were provided to a given genotype (ERIC I-V).
A total of 67 putative genes with different functions were identified. Some were present in all genotypes,
as for example, genes encoding phosphomannomutase, HicB and MazE antitoxins, while others
were exclusive from a specific genotype. In ERIC I, were found genes encoding a DNA internalization
protein or an enhancin-like toxin, in ERIC II, genes responsible for a SocA antitoxin or a DNA
mismatch repair protein, in ERIC III, a gene for a lipid phosphatase, in ERIC IV, genes encoding proteins
associated to ironsulfur uptake and nitrogen fixation and in ERIC V, genes for an aromatic acid
exporter family protein, for an epsilon-toxin type B or for an epithelial and chitin-binding protein.
Although several prophage-derived genes are closely linked to metabolic processes, only ERIC V
strains appear to have a competitive advantage since prophages contained multiple genes that could contribute to a more aggressive infection.
Despite the low representativeness on P. larvae strains diversity, we definitely contribute to leveraging studies in a subject with recent and short knowledge.info:eu-repo/semantics/publishedVersio
Analysis of intact prophages in genomes of Paenibacillus larvae: An important pathogen for bees
The Supplementary materials for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fmicb.2022.903861/full#supplementary-materialPaenibacillus larvae is the etiological agent of American Foulbrood (AFB), a highly contagious and worldwide spread bacterial disease that affects honeybee brood. In this study, all complete P. larvae genomes available on the NCBI database were analyzed in order to detect presence of prophages using the PHASTER software. A total of 55 intact prophages were identified in 11 P. larvae genomes (5.0±2.3 per genome) and were further investigated for the presence of genes encoding relevant traits related to P. larvae. A closer look at the prophage genomes revealed the presence of several putative genes such as metabolic and antimicrobial resistance genes, toxins or bacteriocins, potentially influencing host performance. Some of the coding DNA sequences (CDS) were present in all ERIC-genotypes, while others were only found in a specific genotype. While CDS encoding toxins and antitoxins such as HicB and MazE were found in prophages of all bacterial genotypes, others, from the same category, were provided by prophages particularly to ERIC I (enhancin-like toxin), ERIC II (antitoxin SocA) and ERIC V strains (subunit of Panton-Valentine leukocidin system (PVL) LukF-PV). This is the first in-depth analysis of P. larvae prophages. It provides better knowledge on their impact in the evolution of virulence and fitness of P. larvae, by discovering new features assigned by the viruses.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit. HR was supported by FCT through the grant SFRH/BD/128859/2017 and COVID/BD/151856/2021.info:eu-repo/semantics/publishedVersio
Spent coffee grounds for biodiesel production and other applications
This work evaluates the possibility of using spent coffee grounds (SCG) for biodiesel production and other applications. An experimental study was conducted with different solvents showing that lipid content up to 6 wt% can be obtained from SCG. Results also show that besides biodiesel production, SCG can be used as fertilizer as it is rich in nitrogen, and as solid fuel with higher heating value (HHV) equivalent to some agriculture and wood residues. The extracted lipids were characterized for their properties of acid value, density at 15 °C, viscosity at 40 °C, iodine number, and HHV, which are negatively influenced by water content and solvents used in lipid extraction. Results suggest that for lipids with high free fatty acids (FFA), the best procedure for conversion to biodiesel would be a two-step process of acid esterification followed by alkaline transesterification, instead of a sole step of direct transesterification with acid catalyst. Biodiesel was characterized for its properties of iodine number, acid value, and ester content. Although these quality parameters were not within the limits of NP EN 14214:2009 standard, SCG lipids can be used for biodiesel, blended with higher-quality vegetable oils before transesterification, or the biodiesel produced from SCG can be blended with higher-quality biodiesel or even with fossil diesel, in order to meet the standard requirements
Defence mechanisms of infertile couples vs. fertile couples
Los mecanismos de defensa (DM) fueron investigados en las parejas infértiles (n = 60) a la espera de su primera consulta de infertilidad, haciendo uso del inventario de mecanismos de defensa (DMI). Cuando se comparó con los resultados de las parejas fértiles (n = 60), mujeres y hombres infértiles demostraron una tendencia significativa a evitar el uso de mecanismos de defensa que permitan la expresión de impulsos agresivos, asà como una tendencia al uso excesivo de mecanismos de defensa que permiten la racionalización y la negación de situaciones frustrantes. Estos datos parecen indicar la presencia de rigidez defensiva en las parejas afectadas por estrés reproductivo, mientras que en las parejas en común la flexibilidad defensiva es de esperar.Defence mechanisms (DM) were investigated in infertile couples (n = 60) waiting for their first infertility consultation, making use of the Defense Mechanisms Inventory (DMI). When compared with results of fertile couples (n = 60), infertile men and women showed a significant trend to avoid the use of defence mechanisms that enable the expression of aggressive impulses as well as a tendency to overuse defence mechanisms that enable the rationalization and negation of frustrating situations. Such data seem to indicate the presence of defensive inflexibility in couples affected by reproductive stress, while in common couples defensive flexibility is to be expected.peerReviewe
Solar radiation effect on the complexation capacity of aquatic humic substances with metals
Diversidade da fauna de insectos fitĂłfagos e de inimigos naturais em culturas frutĂcolas da ilha Terceira, Açores: a importância do maneio e da heterogeneidade ambiental
"A evidĂŞncia mostra que os artrĂłpodes constituem uma fracção importante da biodiversidade estrutural e funcional dos habitats terrestres (Kim, 1993). Por outro lado, sĂł Ă© possĂvel conservar os processos ecolĂłgicos associados aos artrĂłpodes promovendo a gestĂŁo correcta dos seus habitats. Para tal, Ă© necessária uma correcta identificação e caracterização das suas comunidades de forma a promover a sua boa gestĂŁo. Durante os Ăşltimos anos tĂŞm sido realizados nos Açores vários estudos de inventariação e caracterização ecolĂłgica dos artrĂłpodes em alguns dos habitats mais importantes destas ilhas: i) habitat cavernĂcola (Borges & OromĂ, 1994); ii) pastagens semi-naturais e intensivas (Borges & Brown, 2001, 2003, 2004); iii) florestas nativas dos Açores (Borges et al., 2000, 2005a, b, 2006; Ribeiro et al., 2005). No entanto, na diversidade de usos do solo das ilhas açoreanas, as fruteiras constituem um habitat mal estudado em termos da cadeia trĂłfica de artrĂłpodes (contudo ver Oliveira, 2002). […]" (da Introdução)
Island and Mountain Ecosystems as Testbeds for Biological Control in the Anthropocene
For centuries, islands and mountains have incited the interest of naturalists, evolutionary biologists and ecologists. Islands have been the cradle for biogeography and speciation theories, while mountain ranges have informed how population adaptation to thermal floors shapes the distribution of species globally. Islands of varying size and mountains’ altitudinal ranges constitute unique “natural laboratories” where one can investigate the effects of species loss or global warming on ecosystem service delivery. Although invertebrate pollination or seed dispersal processes are steadily being examined, biological control research is lagging. While observations of a wider niche breadth among insect pollinators in small (i.e., species-poor) islands or at high (i.e., colder) altitudes likely also hold for biological control agents, such remains to be examined. In this Perspective piece, we draw on published datasets to show that island size alone does not explain biological control outcomes. Instead, one needs to account for species’ functional traits, habitat heterogeneity, host community make-up, phenology, site history or even anthropogenic forces. Meanwhile, data from mountain ranges show how parasitism rates of Noctuid moths and Tephritid fruit flies exhibit species- and context-dependent shifts with altitude. Nevertheless, future empirical work in mountain settings could clarify the thermal niche space of individual natural enemy taxa and overall thermal resilience of biological control. We further discuss how global databases can be screened, while ecological theories can be tested, and simulation models defined based upon observational or manipulative assays in either system. Doing so can yield unprecedented insights into the fate of biological control in the Anthropocene and inform ways to reinforce this vital ecosystem service under global environmental change scenarios.The development of this manuscript was funded by the Food and Agriculture Organization FAO through LOA/RAP/2021/57, executed by The University of Queensland. AS was supported by the "Ramon y Cajal" program (RYC2020029407-I), financed by the Spanish "Ministerio de Ciencia e Innovacion".info:eu-repo/semantics/publishedVersio
Modelling the distribution of a commercial NE-Atlantic sea cucumber, Holothuria mammata : demographic and abundance spatio-temporal patterns
Funding: This study was financed by the Operational Programme Mar2020, MAR-02.01.01-FEAMP-0052, “Newcumber – Avanços para o cultivo sustentável de pepinos do mar”. It received further financial support from Fundação para a Ciência e Tecnologia (projects UIDB/04292/2020, UIDB/00006/2020, CoastNet – PINFRA/22128/2016, AB with the Scientific Stimulus Programme – CEECIND/00095/2017 and FA with the individual research grant 2020.09563.BD). This publication was financed by Portuguese national funds through FCT – Fundação IP under project reference UIDB/04292/2020, and by the European Union’s Horizon 2020 Research and Innovation Program under grant agreement N810139: Project Portugal Twinning for Innovation and Excellence in Marine Science and Earth Observation – PORTWIMS.There is an increasing demand for sea cucumbers, for human consumption, mainly from Asian markets and, as a consequence, NE-Atlantic species are now new targets for exploitation and exportation. Holothuria mammata is one of the most valuable species in Europe. However, the lack of historical economic interest in this species in most European countries has also led to a lack of studies concerning biological and ecological aspects on wild populations and this is a major issue for stock management. This study aims to determine the temporal and spatial patterns of distribution of H. mammata, considering its abundance and demographic structure in a NE-Atlantic area, SW Portugal, as a function of environmental conditions. For that, a population from a marine protected area was followed for 1 year at 1.5-month intervals. Throughout the coastal area, six sites were selected and at each sampling campaign three random transects per site and substrate (rock and sand) in which all H. mammata individuals were counted and measured. For each site and survey several environmental parameters of interest, from the water column, the sediment and substrate cover, were also measured. Generalized Linear Models were used to model the spatial and temporal distribution of the species according to environmental conditions, to determine the species’ habitat preferences. The distribution models indicate that abiotic and biotic parameters of the water column are not the main drivers shaping the distribution of H. mammata. The species has a patchy distribution, and its habitat preferences depend on environmental stability, the presence of shelter and habitat complexity, which is more important for smaller, more vulnerable, individuals, while bigger size classes tend to venture more into less stable environments in an opportunistic fashion. The knowledge of these population traits is determinant to develop stock management measures, which are now urgent to prevent the depletion of commercial sea cucumber populations in the NE-Atlantic. Sustainable fisheries policies should be developed and start by considering to delimit fishing areas and periods, considering the species spatial and temporal distribution patterns.Publisher PDFPeer reviewe
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