Project description:Microbial communities in the rhizosphere make significant contributions to crop health and nutrient cycling. However, their ability to perform important biogeochemical processes remains uncharacterized. Important functional genes, which characterize the rhizosphere microbial community, were identified to understand metabolic capabilities in the maize rhizosphere using GeoChip 3.0-based functional gene array method.
Project description:This study evaluated the ammonium oxidizing communities (COA) associated with a potato crop (Solanum phureja) rhizosphere soil in the savannah of Bogotá (Colombia) by examining the presence and abundance of amoA enzyme genes and transcripts by qPCR and next-generation sequence analysis. amoA gene abundance could not be quantified by qPCR due to problems inherent in the primers; however, the melting curve analysis detected increased fluorescence for Bacterial communities but not for Archaeal communities. Transcriptome analysis by next-generation sequencing revealed that the majority of reads mapped to ammonium-oxidizing Archaea, suggesting that this activity is primarily governed by the microbial group of the Crenarchaeota phylum. In contrast,a lower number of reads mapped to ammonia-oxidizing bacteria.
Project description:• Nicotianamine (NA), a key chelator in plant heavy metal homeostasis, plays a pivotal role in managing Zn bioavailability. In the Zn/Cd hyperaccumulator Arabidopsis halleri, NA is secreted into the rhizosphere, forming stable complexes with Zn to reduce its bioavailability and prevent rapid uptake. However, the NA transporter responsible for this secretion remains unidentified. • Transcriptome analysis of A. halleri and A. thaliana roots with further characterization led to the identification of EFFLUX TRANSPORTER OF NA1 (ENA1) as a plasma membrane-localized NA efflux transporter. ENA1 expression is significantly higher in A. halleri compared to A. thaliana and is induced by excess Zn only in A. halleri. • Increased ENA1 expression promotes NA secretion from roots into the rhizosphere without altering NA accumulation or long-distance root-to-shoot NA transport. Using 67Zn uptake experiments, we found that enhanced NA secretion alleviates Zn toxicity by reducing excess Zn uptake. • Promoter and in situ expression studies showed distinct root expression patterns of ENA1 between A. halleri and A. thaliana, aligning with the species-specific Zn detoxification strategies. • This discovery advances our understanding of Zn homeostasis mechanisms and provides a foundation for developing phytoremediation technologies to manage heavy metal contamination.
2025-08-29 | GSE292775 | GEO
Project description:Metagenomic Sequencing of Soil Samples from Pb/Zn Tailings Contaminated Sites in Southwestern China
Project description:Microbial communities in the rhizosphere make significant contributions to crop health and nutrient cycling. However, their ability to perform important biogeochemical processes remains uncharacterized. Important functional genes, which characterize the rhizosphere microbial community, were identified to understand metabolic capabilities in the maize rhizosphere using GeoChip 3.0-based functional gene array method. Triplicate samples were taken for both rhizosphere and bulk soil, in which each individual sample was a pool of four plants or soil cores. To determine the abundance of functional genes in the rhizosphere and bulk soils, GeoChip 3.0 was used.
Project description:Microbial communities in the rhizosphere make significant contributions to crop health and nutrient cycling. However, their ability to perform important biogeochemical processes remains uncharacterized. Important functional genes, which characterize the rhizosphere microbial community, were identified to understand metabolic capabilities in the maize rhizosphere using GeoChip 3.0-based functional gene array method. Triplicate samples were taken for both rhizosphere and bulk soil, in which each individual sample was a pool of four plants or soil cores. To determine the abundance of functional genes in the rhizosphere and bulk soils, GeoChip 3.0 was used.
Project description:Plants and rhizosphere microbes rely closely on each other, with plants supplying carbon to bacteria in root exudates, and bacteria mobilizing soil-bound phosphate for plant nutrition. When the phosphate supply becomes limiting for plant growth, the composition of root exudation changes, affecting rhizosphere microbial communities and microbially-mediated nutrient fluxes. To evaluate how plant phosphate deprivation affects rhizosphere bacteria, Lolium perenne seedlings were root-inoculated with Pseudomonas aeruginosa 7NR, and grown in axenic microcosms under different phosphate regimes (330 uM vs 3-6 uM phosphate). The effect of biological nutrient limitation was examined by DNA microarray studies of rhizobacterial gene expression.