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Lane, K. R.

Publications and source records attributed to Lane, K. R..

3 recordsLinked to original sources

Deep-sea siliceous sponges harbor distinct and functionally diverse microbiomes

Sponges, phylum Porifera, are long-lived and basal-branching metazoans that play important roles in ocean biogeochemistry and host diverse microbial communities. Siliceous sponges form a major clade of the Porifera, yet their microbiome is not well-characterized, particularly in the deep ocean. Here, we used shotgun metagenomics to investigate the composition of the microbial communities of 13 siliceous sponges collected from four sites near Puerto Rico from depths ranging from 400-1900 meters. Nine of the sponges in this study are from five sponge family taxa that have not previously been sequenced using shotgun metagenomics. We assembled a total of 176 metagenome-assembled-genomes from 20 bacterial and 1 archaeal phyla. Ammonia-oxidizing archaea (AOA) Nitrosopumilaceae dominated most siliceous sponge microbial communities and was strikingly the sole symbiont associated with one sponge (Farrea). Overall, microbiome diversity was relatively low across siliceous sponges, except for a Phloeodictyidae, which was likely a high microbial abundance (HMA) sponge. Our results suggest that host sponge phylogeny may shape microbial community structure, with limited evidence for environmental influence. The sponge-associated microbial communities contained genetic capabilities for diverse metabolic functions, particularly contributing to the carbon, nitrogen, and sulfur cycles. In addition to the AOA, evidence of potential for microbial autotrophy was found through the presence of genes for RuBisCO, methanotrophy, and ATP citrate lyase. These results reveal both conserved relationships and metabolic flexibility across siliceous sponge lineages, suggesting unique evolutionary dynamics and demonstrating the importance of microbial metabolism to sponge host health and nutrient cycling in the oligotrophic deep ocean. ImportanceMarine sponges, emerging [~]600 million years ago, have close relationships with microorganisms, but the microbiome of deep-sea siliceous sponges is not well understood. Siliceous sponges play essential roles in deep-sea ecosystems by providing habitats for other metazoans and mediating carbon, nitrogen, and sulfur cycling, yet they remain some of the least studied sponges. By shotgun sequencing DNA from 13 siliceous sponges collected near Puerto Rico, this study found that host sponge phylogeny influences microbial community composition and structure. Ammonia-oxidizing archaea dominated the microbial communities associated with marine sponges, likely playing key roles in utilizing metabolic byproducts and supporting host health. Other microbes also contributed to nutrient cycling and contained the potential to fix carbon, suggesting metabolic flexibility which may benefit sponge hosts in low-resource environments. These findings emphasize the ecological importance of siliceous sponge-microbe symbioses and contribute to our understanding of the drivers shaping their structure and function.

microbiology↗

Lipid analysis of CO2-rich subsurface aquifers suggests an autotrophy-based deep biosphere with lysolipids enriched in CPR bacteria

Sediment-hosted CO2-rich aquifers deep below the Colorado Plateau (USA) contain a remarkable diversity of uncultivated microorganisms, including Candidate Phyla Radiation (CPR) bacteria that are putative symbionts unable to synthesize membrane lipids. The origin of organic carbon in these ecosystems is unknown and the source of CPR membrane lipids remains elusive. We collected cells from deep groundwater brought to the surface by eruptions of Crystal Geyser, sequenced the community, and analyzed the whole community lipidome over time. Characteristic stable carbon isotopic compositions of microbial lipids suggest that bacterial and archaeal CO2 fixation ongoing in the deep subsurface provides organic carbon for the complex communities that reside there. Coupled lipidomic-metagenomic analysis indicates that CPR bacteria lack complete lipid biosynthesis pathways but still possess regular lipid membranes. These lipids may therefore originate from other community members, which also adapt to high in situ pressure by increasing fatty acid unsaturation. An unusually high abundance of lysolipids attributed to CPR bacteria may represent an adaptation to membrane curvature stress induced by their small cell sizes. Our findings provide new insights into the carbon cycle in the deep subsurface and suggest the redistribution of lipids into putative symbionts within this community.

microbiology↗

Processing of grassland soil C-N compounds into soluble and volatile molecules is depth stratified and mediated by genomically novel bacteria and archaea

Soil microbial activity drives the carbon and nitrogen cycles and is an important determinant of atmospheric trace gas turnover, yet most soils are dominated by organisms with unknown metabolic capacities. Even Acidobacteria, among the most abundant bacteria in soil, remain poorly characterized, and functions across groups such as Verrucomicrobia, Gemmatimonadetes, Chloroflexi, Rokubacteria are understudied. Here, we resolved sixty metagenomic, and twenty proteomic datasets from a grassland soil ecosystem and recovered 793 near-complete microbial genomes from 18 phyla, representing around one third of all organisms detected. Importantly, this enabled extensive genomics-based metabolic predictions for these understudied communities. Acidobacteria from multiple previously unstudied classes have genomes that encode large enzyme complements for complex carbohydrate degradation. Alternatively, most organisms we detected encode carbohydrate esterases that strip readily accessible methyl and acetyl groups from polymers like pectin and xylan, forming methanol and acetate, the availability of which could explain high prevalences of C1 metabolism and acetate utilization in genomes. Organism abundances among samples collected at three soil depths and under natural and amended rainfall regimes indicate statistically higher associations of inorganic nitrogen metabolism and carbon degradation in deep and shallow soils, respectively. This partitioning decreased in samples under extended spring rainfall indicating long term climate alteration can affect both carbon and nitrogen cycling. Overall, by leveraging natural and experimental gradients with genome-resolved metabolic profiles, we link organisms lacking prior genomic characterization to specific roles in complex carbon, C1, nitrate, and ammonia transformations and constrain factors that impact their distributions in soil.

microbiology↗