Project description:Members of the bacterial phylum Spirochaetes are primarily studied for their commensal and pathogenic roles in animal hosts. However, Spirochaetes are also frequently detected in anoxic hydrocarbon-contaminated environments but their ecological role in such ecosystems has so far remained unclear. Here we provide a functional trait to these frequently detected organisms with an example of a sulfate-reducing, naphthalene-degrading enrichment culture consisting of a sulfate-reducing deltaproteobacterium Desulfobacterium naphthalenivorans and a novel spirochete Rectinema cohabitans. Using a combination of genomic, proteomic, and physiological studies we show that R. cohabitans grows by fermentation of organic compounds derived from biomass from dead cells (necromass). It recycles the derived electrons in the form of H2 to the sulfate-reducing D. naphthalenivorans, thereby supporting naphthalene degradation and forming a simple microbial loop. We provide metagenomic evidence that equivalent associations between Spirochaetes and hydrocarbon-degrading microorganisms are of general importance in hydrocarbon- and organohalide-contaminated ecosystems. We propose that environmental Spirochaetes form a critical component of a microbial loop central to nutrient cycling in subsurface environments. This emphasizes the importance of necromass and H2-cycling in highly toxic contaminated subsurface habitats such as hydrocarbon-polluted aquifers.
Project description:Expression data for Desulfovibrio alaskensis strain G20 and mutants in regulator proteins grown on lactate sulfate media and then pelleted and transferred to another media when they reached stationary phase. The Choline mutant was transferred to lacte/sulfate minimal media and choline/sulfate minimal media. The LysX mutant was transferred to minimal media with lysine and rich media. G20 was transferred to minimal media, choline/sulfate minimal media, lactate/choline/sulfate minimal media, minimal media with lysine, and rich media. We aimed to confirm or expand the regulons of each of the transposon interupted regulator mutants and compare gene expression responses of the regulators in different growth conditions. 10 samples were collected: 2 regulator mutants (2 conditions each), Desulfovibrio alaskensis G20 (5 conditions), 2 replicates for G20 minimal media condition. Control sample -G20 rich media.
Project description:Expression data for Desulfovibrio alaskensis strain G20 and mutants in regulator proteins grown on lactate sulfate media and then pelleted and transferred to another media when they reached stationary phase. The Choline mutant was transferred to lacte/sulfate minimal media and choline/sulfate minimal media. The LysX mutant was transferred to minimal media with lysine and rich media. G20 was transferred to minimal media, choline/sulfate minimal media, lactate/choline/sulfate minimal media, minimal media with lysine, and rich media. We aimed to confirm or expand the regulons of each of the transposon interupted regulator mutants and compare gene expression responses of the regulators in different growth conditions.
Project description:We sampled lake-type and riverine sockeye in the pristine natural habitats of Aniakchak National Monument and Preserve, Alaska USA.
Project description:The chorio-decidual interface (CDi) is formed by chorion trophoblasts (CTCs) and immune cell-rich decidua (DECs) cells. The roles of human leukocyte antigen (HLA)-G and progesterone receptor membrane component 2 (PGRMC2) in mediating innate immune homeostasis at this maternal-fetal interface interface were investigated.
