嫌気性炭化水素汚染環境におけるスピロヘータによるネクロマス再循環の媒介
Spirochaetes are commonly found in anoxic groundwater contaminated with hydrocarbons, yet their ecological function in such settings was previously unknown. This study examined an enrichment culture dominated by the sulfate-reducing bacterium Desulfobacterium N47 and the spirochete Rectinema cohabitans HM. Genomic sequencing and proteomic profiling revealed that R. cohabitans functions as an obligate fermenter, breaking down proteins and carbohydrates to yield acetate, ethanol, and molecular hydrogen (H2). Physiological experiments demonstrated that this H2 serves as a key electron donor for sulfate reduction carried out by Desulfobacterium N47, establishing a metabolic link between the two organisms. Differential proteomics further showed that R. cohabitans scavenges biomass released from dead Desulfobacterium N47 cells. Comparative genomic and community analyses indicated that related Rectinema phylotypes are broadly distributed across contaminated habitats and likely share this hydrogenogenic fermentative lifestyle, suggesting that environmental spirochaetes play a widespread role in necromass recycling at anoxic contaminated sites.
R. cohabitans ferments proteins and carbohydrates to produce H2, which is subsequently utilized as an electron donor by Desulfobacterium N47 for sulfate reduction, establishing interspecies hydrogen transfer as the metabolic link between the two bacteria.
This is basic research at the cellular or molecular level. For human application, inhalation is the most promising delivery route, but inhalation carries explosion risk and concentration matters (empirical LFL of 10%; high-concentration devices are not recommended).
See also:
https://h2-papers.org/en/papers/29849169