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The application of beneficial microorganisms for corals (BMC) decreases the bleaching susceptibility and mortality rate of corals. BMC selection is typically performed via molecular and biochemical assays, followed by genomic screening for BMC traits. Herein, we present a comprehensive in silico framework to explore a set of six putative BMC strains. We extracted high-quality DNA from coral samples collected from the Red Sea and performed PacBio sequencing. We identified BMC traits and mechanisms associated with each strain as well as proposed new traits and mechanisms, such as chemotaxis and the presence of phages and bioactive secondary metabolites. The presence of prophages in two of the six studied BMC strains suggests their possible distribution within beneficial bacteria. We also detected various secondary metabolites, such as terpenes, ectoines, lanthipeptides, and lasso peptides. These metabolites possess antimicrobial, antifungal, antiviral, anti-inflammatory, and antioxidant activities and play key roles in coral health by reducing the effects of heat stress, high salinity, reactive oxygen species, and radiation. Corals are currently facing unprecedented challenges, and our revised framework can help select more efficient BMC for use in studies on coral microbiome rehabilitation, coral resilience, and coral restoration.
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Antozoos , Probióticos , Antozoos/genética , Antozoos/microbiología , Antozoos/metabolismo , Animales , Océano Índico , Genómica/métodos , Bacterias/genética , MicrobiotaRESUMEN
Beneficial microorganisms for corals (BMCs), or probiotics, can enhance coral resilience against stressors in laboratory trials. However, the ability of probiotics to restructure the coral microbiome in situ is yet to be determined. As a first step to elucidate this, we inoculated putative probiotic bacteria (pBMCs) on healthy colonies of Pocillopora verrucosa in situ in the Red Sea, three times per week, during 3 months. pBMCs significantly influenced the coral microbiome, while bacteria of the surrounding seawater and sediment remained unchanged. The inoculated genera Halomonas, Pseudoalteromonas, and Bacillus were significantly enriched in probiotic-treated corals. Furthermore, the probiotic treatment also correlated with an increase in other beneficial groups (e.g., Ruegeria and Limosilactobacillus), and a decrease in potential coral pathogens, such as Vibrio. As all corals (treated and non-treated) remained healthy throughout the experiment, we could not track health improvements or protection against stress. Our data indicate that healthy, and therefore stable, coral microbiomes can be restructured in situ, although repeated and continuous inoculations may be required in these cases. Further, our study provides supporting evidence that, at the studied scale, pBMCs have no detectable off-target effects on the surrounding microbiomes of seawater and sediment near inoculated corals.
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Antozoos , Bacillus , Microbiota , Probióticos , Vibrio , Animales , Antozoos/microbiologíaRESUMEN
The Red Sea is a suitable model for studying coral reefs under climate change due to its strong environmental gradient that provides a window into future global warming scenarios. For instance, corals in the southern Red Sea thrive at temperatures predicted to occur at the end of the century in other biogeographic regions. Corals in the Red Sea thrive under contrasting thermal and environmental regimes along their latitudinal gradient. Because microbial communities associated with corals contribute to host physiology, we conducted a systematic review of the known diversity of Red Sea coral-associated bacteria, considering geographic location and host species. Our assessment comprises 54 studies of 67 coral host species employing cultivation-dependent and cultivation-independent techniques. Most studies have been conducted in the central and northern Red Sea, while the southern and western regions remain largely unexplored. Our data also show that, despite the high diversity of corals in the Red Sea, the most studied corals were Pocillopora verrucosa, Dipsastraea spp., Pleuractis granulosa, and Stylophora pistillata. Microbial diversity was dominated by bacteria from the class Gammaproteobacteria, while the most frequently occurring bacterial families included Rhodobacteraceae and Vibrionaceae. We also identified bacterial families exclusively associated with each of the studied coral orders: Scleractinia (n = 125), Alcyonacea (n = 7), and Capitata (n = 2). This review encompasses 20 years of research in the Red Sea, providing a baseline compendium for coral-associated bacterial diversity.
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Octocorals (Cnidaria, Anthozoa Octocorallia) are magnificent repositories of natural products with fascinating and unusual chemical structures and bioactivities of interest to medicine and biotechnology. However, mechanistic understanding of the contribution of microbial symbionts to the chemical diversity of octocorals is yet to be achieved. This review inventories the natural products so-far described for octocoral-derived bacteria and fungi, uncovering a true chemical arsenal of terpenes, steroids, alkaloids, and polyketides with antibacterial, antifungal, antiviral, antifouling, anticancer, anti-inflammatory, and antimalarial activities of enormous potential for blue growth. Genome mining of 15 bacterial associates (spanning 12 genera) cultivated from Eunicella spp. resulted in the identification of 440 putative and classifiable secondary metabolite biosynthetic gene clusters (BGCs), encompassing varied terpene-, polyketide-, bacteriocin-, and nonribosomal peptide-synthase BGCs. This points towards a widespread yet uncharted capacity of octocoral-associated bacteria to synthetize a broad range of natural products. However, to extend our knowledge and foster the near-future laboratory production of bioactive compounds from (cultivatable and currently uncultivatable) octocoral symbionts, optimal blending between targeted metagenomics, DNA recombinant technologies, improved symbiont cultivation, functional genomics, and analytical chemistry are required. Such a multidisciplinary undertaking is key to achieving a sustainable response to the urgent industrial demand for novel drugs and enzyme varieties.
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Antozoos/microbiología , Bacterias/metabolismo , Productos Biológicos/farmacología , Vías Biosintéticas/genética , Hongos/metabolismo , Animales , Bacterias/genética , Productos Biológicos/aislamiento & purificación , Productos Biológicos/metabolismo , Hongos/genética , Microbiología Industrial/métodos , Microbiota/fisiología , Familia de Multigenes , Simbiosis , Tecnología Farmacéutica/métodosRESUMEN
BACKGROUND: Information dealing with social and behavioural risk factors as well as their mechanisms among Mozambican migrants working in South African mines remains undocumented. This study aims to understand the various factors influencing HIV-related risk behaviours and the resulting HIV positive status of Mozambican miners employed by South African mines. This analysis was undertaken in order to inform a broader and more effective HIV preventive framework in Mozambique. METHOD: This study relied upon data sourced from the first Integrated Biological and Behavioural Survey among Mozambican miners earning their living in South African mines. It employs quantitative techniques using standard statistical tools to substantiate the laid-down objectives. The primary technique applied in this paper is the multivariable statistical method used in the formulation and application of a proximate determinants framework. RESULTS: The odds of reporting one sexual partner were roughly three times higher for miners working as perforators as opposed to other types of occupation. As well, the odds of condom use - always or sometimes - for miners in the 31-40 age group were three times higher than the odds of condom use in the 51+ age group. Miners with lower education levels were less likely to use condoms. The odds of being HIV positive when the miner reports use of alcohol or drugs (sometimes/always) is 0.32 times lower than the odds for those reporting never use of alcohol or drugs. And finally, the odds of HIV positive status for those using condoms were 2.16 times that of miners who never used condoms, controlling for biological and other proximate determinants. CONCLUSION: In Mozambique, behavioural theory emphasising personal behavioural changes is the main strategy to combat HIV among miners. Our findings suggest there is a need to change thinking processes about how to influence safer sexual behaviour. This is viewed to be the result of a person's individual decision, due to of the complexity of social and contextual factors that may also influence sexual behaviours. This only stresses the need for HIV prevention strategies to exclusively transcend individual factors while considering the broader social and contextual phenomena influencing HIV risk among Mozambican miners.
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Infecciones por VIH/prevención & control , Minería , Asunción de Riesgos , Conducta Sexual/psicología , Migrantes/psicología , Adolescente , Adulto , Condones/estadística & datos numéricos , Infecciones por VIH/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Mozambique/epidemiología , Factores de Riesgo , Parejas Sexuales/psicología , Factores Socioeconómicos , Encuestas y Cuestionarios , Migrantes/estadística & datos numéricos , Adulto JovenRESUMEN
Background: Information dealing with social and behavioural risk factors as well as their mechanisms among Mozambican migrants working in South African mines remains undocumented. This study aims to understand the various factors influencing HIV-related risk behaviours and the resulting HIV positive status of Mozambican miners employed by South African mines. This analysis was undertaken in order to inform a broader and more effective HIV preventive framework in Mozambique. Method: This study relied upon data sourced from the first Integrated Biological and Behavioural Survey among Mozambican miners earning their living in South African mines. It employs quantitative techniques using standard statistical tools to substantiate the laid-down objectives. The primary technique applied in this paper is the multivariable statistical method used in the formulation and application of a proximate determinants framework. Results: The odds of reporting one sexual partner were roughly three times higher for miners working as perforators as opposed to other types of occupation. As well, the odds of condom use always or sometimes for miners in the 31-40 age group were three times higher than the odds of condom use in the 51+ age group. Miners with lower education levels were less likely to use condoms. The odds of being HIV positive when the miner reports use of alcohol or drugs (sometimes/always) is 0.32 times lower than the odds for those reporting never use of alcohol or drugs. And finally, the odds of HIV positive status for those using condoms were 2.16 times that of miners who never used condoms, controlling for biological and other proximate determinants. Conclusion: In Mozambique, behavioural theory emphasising personal behavioural changes is the main strategy to combat HIV among miners. Our findings suggest there is a need to change thinking processes about how to influence safer sexual behaviour. This is viewed to be the result of a person's individual decision, due to of the complexity of social and contextual factors that may also influence sexual behaviours. This only stresses the need for HIV prevention strategies to exclusively transcend individual factors while considering the broader social and contextual phenomena influencing HIV risk among Mozambican miners.
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Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Conducta Sexual/psicología , Migrantes/psicología , Infecciones por VIH/prevención & control , Factores Socioeconómicos , Migrantes/estadística & datos numéricos , Parejas Sexuales/psicología , Infecciones por VIH/epidemiología , Encuestas y Cuestionarios , Condones/estadística & datos numéricos , MozambiqueRESUMEN
BACKGROUND: Research has demonstrated a link between alcohol use and risky sexual behaviour among different types of migrant populations. Therefore, research investigating risk factors associated with alcohol consumption among them is a public health priority. This review aimed to explore the intersection between migration, alcohol consumption and risky sexual behaviour. METHODS: This article is a synthetic review of empirical studies on the association of alcohol and high-risk sexual behaviour among different types of the migrant populations, focusing on measurable outcomes generated from quantitative data. A descriptive analysis generated from global and situational studies was used to interpret the reviewed research and to discuss critically the factors that drive migrants to engage in alcohol consumption and high-risk behaviour. RESULTS: This review found out that there is a significant and positive association between global and situational alcohol use and several outcomes of risky sexual behaviour among different types of migrant populations. This association was however mainly observed at high quantities and frequencies of alcohol use, mainly among male migrants, and was often tied to a specific situation or context, for instance the type of sexual partner, the level of mobility and to environmental factors such as living arrangements and entertainment venues. CONCLUSIONS: The study supports previous research that alcohol use is associated with risky sexual behaviour among different types of migrant populations. Therefore, future interventions should target mobile, male migrant heavy drinkers. Additional research is needed using more event-level and longitudinal methodologies that overcome prior methodological limitations.
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This article examines the association between risky sexual behavior and HIV risk perception among miners. A cross-sectional survey (n = 293) was conducted with miners who worked in South African mines and lived in the Chokwe district of Gaza Province in southern Mozambique. The study used ordinary logistic and cumulative logistic models to understand what drives miners to HIV susceptibility. The study revealed that most miners were at risk of HIV infection as a result of risky sexual behavior. However, there was a strong negative association between risky sexual behavior and HIV risk perception. Seventy percent of the miners practicing risky sexual behavior reported low HIV risk perception. This demonstrates that miners tend to underestimate their HIV risk, which makes them more susceptible to contracting HIV. Risk perception among miners is related to a range of factors, both individual and environmental. Informed risk awareness is essential for these men to adopt preventive measures against HIV/AIDS. Therefore, it is important to consider cultural beliefs, as they influence the understanding of HIV risk perception.