Project description:Xiangjiang River (Hunan, China) has been contaminated with heavy metal for several decades by surrounding factories. However, little is known about the influence of a gradient of heavy metal contamination on the diversity, structure of microbial functional gene in sediment. To deeply understand the impact of heavy metal contamination on microbial community, a comprehensive functional gene array (GeoChip 5.0) has been used to study the functional genes structure, composition, diversity and metabolic potential of microbial community from three heavy metal polluted sites of Xiangjiang River.
Project description:Marine sediments harbor highly diverse microbial communities that contribute to global biodiversity and play essential roles in the ecosystem functioning. However, the metaproteome of marine sediments remains poorly understood. Extracting proteins from environmental samples can be challenging, especially in marine sediments due to their complex matrix. Few studies have been conducted on improving protein extraction methods from marine sediments. To establish an effective protein extraction workflow for clay-rich sediments, we compared, combined and improved several protein extraction methods. The presented workflow includes blocking of protein binding sites on sediment particles with high concentrations of amino acids, effective cell lysis via ultra-sonication, and the electro-elution and simultaneous fractionation of proteins. Using this workflow, we were able to recover 100% of the previously added Escherichia coli proteins from the sediment.
Project description:Xiangjiang River (Hunan, China) has been contaminated with heavy metal for several decades by surrounding factories. However, little is known about the influence of a gradient of heavy metal contamination on the diversity, structure of microbial functional gene in sediment. To deeply understand the impact of heavy metal contamination on microbial community, a comprehensive functional gene array (GeoChip 5.0) has been used to study the functional genes structure, composition, diversity and metabolic potential of microbial community from three heavy metal polluted sites of Xiangjiang River. Three groups of samples, A, B and C. Every group has 3 replicates.
Project description:Identifying the taxonomy of bone fragments in resin-embedded archaeological sediment blocks can provide information about our past at a microstratigraphic resolution. Here, we first explore the effects of resin impregnation on modern bones, and find minimal effects on taxonomic identifications, but an increase in oxidation-related PTMs. We thereafter apply the method on Pleistocene resin-embedded sediment blocks from the archaeological sites of Bacho Kiro, La Ferrassie, and Quinçay. For two out of three sites, the taxonomic identifications are highly successful, reflecting a faunal composition previously identified at the site. For the last site, Quinçay, we find poor protein preservation in the sediment block that was sampled and a lower success rate of taxonomic identifications. Our results show that palaeoproteomic information can be derived from sediment blocks, allowing study of the past at a much higher resolution.