Biology subjects

Falcao Salles, J.

Publications and source records attributed to Falcao Salles, J..

3 recordsLinked to original sources

bioRxiv2023

Diverse rhizosphere-associated Pseudomonas genomes isolated along the marine-terrestrial transition zone of a Wadden island salt march

Soil microbes are key drivers of ecosystem processes promoting nutrient cycling, system productivity, and resilience. While much is known about the roles of microbes in established systems, their impact on soil development and the successional transformation over time remains poorly understood. Here, we provide 67 diverse, rhizosphere-associated Pseudomonas draft genomes from an undisturbed salt march primary succession spanning >100 years of soil development. Pseudomonas are cosmopolitan bacteria with a significant role in plant establishment and growth. We obtained isolates associated with Limonium vulgare and Artemisia maritima, two typical salt marsh perennial plants with roles in soil stabilization, salinity regulation, and biodiversity support. We anticipate that our data, in combination with the provided physiochemical measurements, will help identify genomic signatures associated with the different selective regimes along the successional stages, such as varying soil complexity, texture, and nutrient availability. Such findings would not only advance our understanding of Pseudomonas role in natural soil ecosystems but also provide the basis for a better understanding of the roles of microbes throughout ecosystem transformations.

genomics↗

bioRxiv2022

Gut microbiota of homing pigeons shows summer-winter variation under constant diet indicating a substantial effect of temperature

BackgroundGut microbiotas play a pivotal role in host physiology and behaviour, and may affect host life-history traits such as seasonal variation in host phenotypic state. Generally, seasonal gut microbiota variation is attributed to seasonal diet variation. However, seasonal temperature and day length variation may also drive gut microbiota variation. We investigated summer-winter differences in gut microbiota in 14 homing pigeons living outdoors under a constant diet by collecting cloacal swabs in both seasons during two years. Because temperature effects may be mediated by host metabolism, we determined basal metabolic rate (BMR) and body mass. Immune competence is influenced by day length and has a close relationship with gut microbiota, and it may thus be a link between day length and gut microbiota. Therefore, we measured seven innate immune indices. We expected gut microbiota to show summer-winter differences and gut microbiota to correlate with metabolism and immune indices. ResultsBMR, body mass, and two immune indices varied seasonally, other host factors did not. Gut microbiota showed differences between seasons and sexes, and correlated with metabolism and immune indices. The most abundant genus (Lachnoclostridium 12, 12%) and associated higher taxa, were more abundant in winter, though not significantly at the phylum level, Firmicutes. Bacteroidetes were more abundant in summer. The Firmicutes:Bacteroidetes ratio tended to be higher in winter. The KEGG ortholog functions for fatty acid biosynthesis and linoleic acid metabolism (PICRUSt2) had increased abundances in winter. ConclusionsThe gut microbiota of homing pigeons varied seasonally, even under a constant diet. The correlations between immune indices and gut microbiota did not involve consistently specific immune indices and included only one of the two immune indices that showed seasonal differences, suggesting that immune competence may be an unlikely link between day length and gut microbiota. The correlations between gut microbiota and metabolism indices, the higher Firmicutes:Bacteroidetes ratio in winter, and the resemblance of the summer-winter differences in gut microbiota with the general temperature effects on gut microbiota in the literature, suggest that temperature partly drove the summer-winter differences in gut microbiota in homing pigeons.

microbiology↗

bioRxiv2022

Insights into the microbial strain mediated impact on pest insect development

Molecular analyses of host-associated microorganisms have demonstrated the essential role that the microbiome plays in host development. Approaches targeting the sequencing of ribosomal genes have successfully identified key species of the host-associated microbiome. However, it remains unclear to what extent the strain-specific characteristics influence the outcome of the host-microbiome interactions. This is particularly important for insect pests, where microbial species might be used as targets for biocontrol purposes. Understanding strain-level variation represents thus a crucial step in determining the microbial impact on hosts. To investigate the microbial strain-level effects on an invasive insect pest, Drosophila suzukii, we compared the impact of monocultures and cocultures of different bacterial and yeast strains. We investigated whether different strains of Gluconobacter and Pichia differentially influenced the larval development of the pest. Fly trait measurements demonstrated beneficial, although variable, impact of these microbial strains on the fitness of suzukii. Using cocultures of microbial strains, we found that in some combinations, the beneficial effects were intermediate between those of the respective monocultures. In contrast, in other cases, strong inhibitory effects were observed. Hence, our study reports that strain-level effects within species are present in D. suzukii, reinforcing the importance of assessing the impact of associated microbiota on pest insects at the strain level. HighlightsO_LIMicrobial strains make up an essential part of the diversity of an insect hosts C_LIO_LICharacterizing and accounting for strain-specific impact on a pests life-history traits and different combinations of strains constitute an important step in our understanding of the pest management strategies. C_LIO_LIWe investigated whether there was any strain-specific impact of bacteria and yeasts on the larval development of a frugivorous pest. C_LIO_LIWe observed that strains varied in their impact, both as monocultures and cocultures, indicating their importance in modifying the host ecology. C_LIO_LIOur study adds to the growing literature on the importance of strains in pest insects. C_LI

ecology↗