Biology subjects

Mendes, L. W.

Publications and source records attributed to Mendes, L. W..

3 recordsLinked to original sources

bioRxiv2026

Leaf and root microbiome signatures of gray mangrove trees in the Red Sea

Mangroves persist under strong environmental constraints with support from microbes. Although microbial communities differ among mangrove compartments, their assembly mechanisms and compartment-specific functional signatures remain poorly resolved. Here, we combine peptide nucleic acid-clamping coupled with 16S rRNA gene amplicon sequencing and genome-resolved metagenomics to investigate the microbial communities associated with the leaves and roots of gray mangrove trees in the Red Sea. Our results suggest homogeneous selection and homogenizing dispersal as key processes of microbial community assembly in leaves. This phyllosphere hosts novel prokaryotic lineages, with some of its members probably synthesizing rhodopsins, plant polysaccharide-degrading enzymes, and gamma-aminobutyric acid, a metabolite that increase tolerance to salinity stress. Genomes affiliated with Desulfobacterales and Sedimenticolaceae taxa are abundant belowground, suggesting complementary sulfur- and nitrogen-cycling capacities similar as occur in other blue-carbon ecosystems. Comparison with root-derived genomes from cordgrass revealed a host-driven selection of Sedimenticolaceae species with convergent metabolic profiles. Overall, this study provides an integrative view about the microbial biology of gray mangrove trees, offering foundational insights into the diversity, ecology, and predictive functionality of their aboveground-belowground microbiomes.

microbiology↗

bioRxiv2025

Identifying associations between maize leaf transcriptome and bacteriome during different diurnal periods

O_LIBacterial communities play important roles in the plant phyllosphere. Both microbial communities and their hosts have circadian rhythms and are subject to diurnal environmental changes. However, the interaction between the host and microbiome is still poorly understood. Here, we exploit paired sequencing data of host transcriptome and microbiome derived maize genotypes in field conditions and under two contrasting diurnal periods. C_LIO_LIGene expression patterns of circadian cycle genes confirmed expected diurnal dynamics. Groups of co-expressed genes that responded to diurnal periods were associated with nucleic acid-binding, heat stress responses, and photosynthesis. C_LIO_LIMicrobiome analysis revealed only modest differences in alpha diversity between midday and midnight samples. However, beta diversity indicated a significant shift in community composition. Co-occurrence network analysis identified keystone taxa specific to each time point, suggesting time-dependent ecological roles within the phyllosphere microbiome. C_LIO_LICross-correlation analyses between host gene expression and bacterial taxon abundance revealed a greater number of host-microbe associations during the night. Several maize genes involved in circadian regulation significantly correlated with microbial taxa. Our findings provide initial evidence for diurnal-associated relationships between host gene expression and leaf-associated bacteriome, suggesting that maize circadian regulation may play a role in shaping the composition and functional potential of the phyllosphere microbiome. C_LI

bioinformatics↗

bioRxiv2021

Maintaining grass coverage increases methane uptake in Amazonian pasture soils

Cattle ranching is the largest driver of deforestation in the Brazilian Amazon. The rainforest- to-pasture conversion affects the methane cycle in upland soils, changing it from sink to source of atmospheric methane. However, it remains unknown if management practices could reduce the impact of land-use on methane cycling. In this work, we evaluated how pasture management can regulate the soil methane cycle either by maintaining continuous grass coverage on pasture soils, or by liming the soil to amend acidity. Methane fluxes from forest and pasture soils were evaluated in moisture-controlled greenhouse experiments with and without grass cover (Urochloa brizantha cv. Marandu) or liming. In parallel, we assessed changes in the soil microbial community structure of both bare pasture soil as well as rhizosphere soil through high throughput sequencing of the 16S rRNA gene, and quantified the methane cycling microbiota by their respective marker genes related to methane generation (mcrA) or oxidation (pmoA). The experiments used soils from eastern and western Amazonia, and concurrent field studies allowed us to confirm greenhouse data. The presence of a grass cover not only increased methane uptake by up to 35% in pasture soils, but also reduced the abundance of the methane-producing community. In the grass rhizosphere this reduction was up to 10-fold. Methane-producing archaea belonged to the genera Methanosarcina sp., Methanocella sp., Methanobacterium sp., and Rice Cluster I. Further, we showed that liming compromised the capacity of forest and pasture soils to be a sink for methane, and instead converted formerly methane-consuming forest soils to become methane sources in only 40-80 days. Our results demonstrate that pasture management that maintains grass coverage can mitigate soil methane emissions, if compared to a bare pasture soil.

microbiology↗