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Biology subjects

Rasmussen, J. A.

Publications and source records attributed to Rasmussen, J. A..

6 recordsLinked to original sources

Optimizing seagrass planting arrangements for animal benefits in a multi-habitat restoration seascape

Restoring lost and degraded ecosystems to enhance biodiversity and ecosystem services is a global priority, and animal responses to the restoration of habitats are a critical but undervalued component. Identifying the key drivers of animal colonization in restored habitats provides critical insights for restoration practitioners seeking to maximize ecological outcomes. When integrated into predictive frameworks and spatial decision- support tools, this knowledge becomes especially valuable for strategic planning, particularly in complex multi-habitat restoration projects where spatial configuration remains a crucial yet understudied dimension influencing ecosystem recovery trajectories. We collect and analyze animal data from one of the worlds largest multi- habitat coastal restoration systems in Denmark, comprising restored seagrass (Zostera marina), boulder reefs and mussel reefs. Using fine-scale spatial patterns in population abundances, we develop spatially explicit predictions across the seascape for various seagrass restoration scenarios and produce a series of optimizations, showing that it is practical to configure restoration to optimize biodiversity objectives, including those linked with fished species. Species-specific responses translated to variable outcomes across restoration scenarios and optimizations. While the optimal number and arrangement of restored patches varied depending on the target species or species group (e.g., fisheries species or seagrass specialists), one near-ubiquitous arrangement was patchy seagrass planting. This aligns with current practice, maximizes restoration efficiency, and highlights the importance of not homogenizing seascapes for biodiversity. Our approach provides a practical framework for incorporating animal monitoring data into restoration planning, helping practitioners design and optimize spatial planting configurations to achieve specific ecological objectives. Open Research StatementAll data and code/scripts (R language), including a README file, are freely available at: https://github.com/msievers100/DenmarkSpatial

ecology↗

Possible origins of kombucha in spontaneous fermentation

Although the microbial composition and functional attributes of kombucha have been extensively studied, the origins and mechanisms of the formation of their biofilm (Symbiotic Culture of Bacteria and Yeasts, or SCOBY) remain speculative. Based on historical reports and the concept of community coalescence, this study establishes a proof-of-concept, demonstrating how a kombucha-like biofilm can form spontaneously from microbes associated with plants, insects, and humans in a sweetened tea medium. Metagenomic analyses revealed microbial dynamics during fermentation, uncovering shifts in community composition driven by acetic acid bacteria, lactic acid bacteria, and yeasts. Comparative analyses with existing fermented beverages demonstrated microbial similarities to kombucha metagenomes. Pangenomic analyses focused on Fructobacillus evanidus, a species present in both the bee microbiome and our spontaneous fermentation. The MAGs of F. evanidus from the fermented beverage showed evidence of genetic streamlining, characterized by the loss of genes essential for survival in shifting and highly competitive environments, such as the bee gut, and adaptation to the more stable conditions of fermentation. This study offers insights into the origins of kombucha, integrating historical, microbiological, ecological and evolutionary perspectives to answer the question Is this a kombucha?, and gesturing toward further physical, chemical and sensory dimensions that could be explored.

microbiology↗

The Salmon Microbial Genome Atlas enables novel insights into bacteria-host interactions via functional mapping

The essential role of the gut microbiota for host health and nutrition is well established for many terrestrial animals, while its importance for fish and particularly Atlantic salmon is unclear. Here, we present the Salmon Microbial Genome Atlas (SMGA) originating from wild and farmed fish both in freshwater and seawater, and consisting of 211 high-quality bacterial genomes, recovered by cultivation (n=131) and gut metagenomics (n=80). Bacterial genomes were taxonomically assigned into 14 different orders, including 28 distinctive genera and 31 potentially novel species. Benchmarking the SMGA, we functionally characterized key populations in the salmon gut that were detected in vivo. This included the ability to degrade diet-derived fibers and release vitamins and other exo-metabolites with known beneficial effects, which were validated by in vitro cultivation and untargeted metabolomics. Together, the SMGA enables high resolution functional insight into salmon gut microbiota with relevance for salmon nutrition and health.

microbiology↗

Host-gut microbiota interactions shape parasite infections in farmed Atlantic salmon

Animals and their associated microbiota share long evolutionary histories. Both host genotype and associated microbiota influence phenotypes such as growth and disease resilience. We applied a hologenomic approach to explore the relationship between host and microbiota in shaping lifetime growth and parasitic cestode infection in farmed Atlantic salmon. Genomes, transcriptomes, metabolomes and metagenomes were generated from the guts of 460 harvest-aged salmon, 82% of which were naturally infected with an intestinal cestode. One salmonid-specific Mycoplasma dominated the gut microbiota of uninfected salmon. However, the microbiota was perturbed in smaller, parasitised fish, with increased abundance of Vibrionaceae and other Mycoplasma species previously linked to the cestode microbiota. The cestode-associated Mycoplasma carry more virulence-associated genes than the salmonid Mycoplasma. Colonisation by one cestode-associated Mycoplasma was associated with a region of the salmon genome encoding several long noncoding RNA genes previously associated with host control of intestinal microbiota. Integrating the multiple omic datasets revealed coordinated changes in the salmon gut transcriptome and metabolome that correlated with shifts in the microbiota of smaller, parasitised fish. Our results suggest that cestode infections introduce new microbes and trigger host responses, altering the gut microbiota with increases in potentially pathogenic microbes. Establishment of these microbes is partially shaped by the genetic background of the host. Our study highlights the value of a hologenomic approach for gaining an in-depth understanding of trilateral interactions among host, microbiota and parasite.

systems biology↗

The Rhizosphere Bacterial Communities Differ Among Domesticated Maize Landraces - An Experimental Confirmation

O_LIThe plant-associated microbiome has been shown to vary considerably between species and across environmental gradients. The effects of genomic variation on the microbiome within single species are less clearly understood, with results often confounded by the larger effects of climatic and edaphic variation. C_LIO_LIIn this study, the effect of genomic variation on the rhizosphere bacterial communities of maize was investigated by comparing different genotypes grown within controlled environments. Rhizosphere bacterial communities were profiled by metabarcoding the universal bacterial 16S rRNA v3-v4 region. Initially, plants from the inbred B73 line and the Ancho - More 10 landrace were grown for 12- weeks and compared. The experiment was then repeated with an additional four Mexican landraces (Apachito - Chih 172, Tehua - Chis 204, Serrano - Pueb 180 and Hairnoso de Ocho) that were grown alongside additional B73 and Ancho - More 10 genotypes. C_LIO_LIIn both experiments there were significant genotypic differences in the rhizosphere bacteria. Additionally, the bacterial communities were significantly correlated with genomic distance between genotypes, with the more closely related landraces being more similar in rhizosphere bacterial communities. C_LIO_LIDespite limited sampling numbers, here we confirm that genomic variation in maize landraces is associated with differences in the rhizosphere bacterial communities. Further studies that go beyond correlations to identify the mechanisms that determine the genotypic variation of the rhizosphere microbiome are required. C_LI

microbiology↗

Desert Dingo (Canis lupus dingo) genome provides insights into their role in the Australian ecosystem.

The dingo is Australias iconic top-order predator and arrived on the continent between 5,000-8,000 years ago. To provide an unbiased insight into its evolutionary affiliations and biological interactions, we coupled long-read DNA sequencing with a multiplatform scaffolding approach to produce an ab initio genome assembly of the desert dingo (85X coverage) we call CanLup_DDS. We compared this genome to the Boxer (CanFam3.1) and German Shepherd dog (CanFam_GSD) assemblies and characterized lineage-specific and shared genetic variation ranging from single- to megabase pair-sized variants. We identified 21,483 dingo-specific and 16,595 domestic dog-specific homozygous structural variants mediating genic and putative regulatory changes. Comparisons between the dingo and domestic dog builds detected unique inversions on Chromosome 16, structural variations in genes linked with starch metabolism, and seven differentially methylated genes. To experimentally assess genomic differences 17 dingoes and 15 German Shepherd dogs were fed parallel diets for 14 days. In dingoes, low AMY2B copy number and serum amylase levels are linked with high cholesterol and LDL levels. Gut microbiome analyses revealed enrichment of the family Clostridiaceae, which can utilize complex resistant starch, while scat metabolome studies identified high phenylethyl alcohol concentrations that we posit are linked with territory marking. Our study provides compelling genomic, microbiome, and metabolomic links showing the dingo has distinct physiology from domestic breed dogs with a unique role in the ecosystem.

genomics↗