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Biology subjects

Bergstrom, G.

Publications and source records attributed to Bergstrom, G..

3 recordsLinked to original sources

Gut bacteria impact host uric acid burden and its association with atherosclerosis

Humans with metabolic and inflammatory diseases, including atherosclerosis harbor dysbiotic gut communities. However, the microbes and microbial pathways that influence disease progression remain largely undefined. Here, we show that variation in atherosclerosis burden is in part driven by the gut microbiota and it is associated with circulating levels of the proinflammatory molecule uric acid both in mice and humans. We identify bacterial taxa present in the gut spanning multiple phyla, including Bacillota (Firmicutes), Fusobacteriota and Pseudomonadota (Proteobacteria), that use uric acid and adenine- a key precursor of nucleic acids in intestinal cells, as carbon and energy sources anaerobically, and uncover a gene cluster encoding key steps of purine degradation that is widely distributed among gut dwelling bacteria. Furthermore, we demonstrate that colonization of germ-free mice with purine-degrading bacteria modulates levels of uric acid and other purines in the gut and systemically. Altogether this work demonstrates that gut microbes are important drivers of host global purine homeostasis and uric acid levels, and suggests that gut bacterial catabolism of purines may represent a novel mechanism by which the gut microbiome influences host health.

microbiology↗

Human immune system variation during one year

The human immune system varies extensively between individuals, but variation within individuals over time has not been well characterized. Systems-level analyses allow for simultaneous quantification of many interacting immune system components, and the inference of global regulatory principles. Here we present a longitudinal, systems-level analysis in 99 healthy adults, 50 to 65 years of age and sampled every 3rd month during one year. We describe the structure of inter-individual variation and characterize extreme phenotypes along a principal curve. From coordinated measurement fluctuations, we infer relationships between 115 immune cell populations and 750 plasma proteins constituting the blood immune system. While most individuals have stable immune systems, the degree of longitudinal variability is an individual feature. The most variable individuals, in the absence of overt infections, exhibited markers of poor metabolic health suggestive of a functional link between metabolic and immunologic homeostatic regulation. HIGHLIGHTSLongitudinal variation in immune cell composition during one year Inter-individual variation can be described along a principal curve Immune cell and protein relationships are inferred Variability over time is an individual feature correlating with markers of poor metabolic health

immunology↗

Genome-Wide Associations with Resistance to Bipolaris Leaf Spot (Bipolaris oryzae (Breda de Haan) Shoemaker) in a Northern Switchgrass Population (Panicum virgatum)

Switchgrass (Panicum virgatum L.), a northern native perennial grass, suffers from yield reduction from Bipolaris leaf spot caused by Bipolaris oryzae (Breda de Haan) Shoe-maker. This study aimed for determining the resistant populations via multiple phenotyping approaches and identifying potential resistance genes to the disease from genome-wide association studies in the switchgrass northern association panel. The disease resistance was evaluated from both natural (field evaluations in NY and PA) and artificial inoculations (detached leaf and leaf disk assays). There are ten out of the 66 populations showed the most resistant based on a combination of detached leaf, leaf disk, and mean from two locations. The GWAS from five subgroups from the association panel to different disease evaluation combinations yielded 27 significant SNPs on 12 chromosomes: 1K, 2K, 2N, 3K, 3N, 4N, 5K, 5N, 6N, 7K, 7N, and 9N accumulatively explaining phenotypic variance of BLUPs of detached leaf percent lesion via image analysis 26.52% at most and BLUPs of leaf disk percent lesion via image analysis 3.28% at least. Within linkage disequilibrium of 20 kb, these SNP markers linked with the potential resistance genes including genes encoding for NBS-LRR, PPR, cell wall related proteins, homeostatic proteins, anti-apoptotic proteins, and ABC transporters.

bioinformatics↗