Cysteine: an overlooked energy and carbon source
Luise Göbbels1, Anja Poehlein2, Albert Dumnitch1
1Microbiology and Biotechnology, Institute of Plant Sciences and Microbiology, University of Hamburg, 22609, Hamburg, Germany.
Scientific Reports
|January 26, 2021
Summary
Microorganism-nanoparticle biohybrids show promise for bioenergy. This study reveals how Moorella thermoacetica metabolizes cysteine in biohybrids, independent of nanoparticles or light, yielding acetate.
Area of Science:
- Microbiology
- Nanotechnology
- Biochemistry
Background:
- Microorganism-nanoparticle biohybrids are explored for bioenergy and chemical production.
- Cellular and metabolic processes in these systems remain poorly understood.
Purpose of the Study:
- To elucidate the physiological and metabolic roles of Moorella thermoacetica in a biohybrid with cadmium sulfide nanoparticles.
- To investigate the impact of cadmium sulfide nanoparticles and light on bacterial metabolism.
Main Methods:
- Physiological analysis
- Metabolic profiling
- Enzymatic assays
- Transcriptomic analysis
Main Results:
- Moorella thermoacetica metabolizes L-cysteine to acetate in the biohybrid, independent of cadmium sulfide (CdS) or light.
- CdS-containing cells exhibit enhanced metabolic activity due to an intracellular storage compound linked to arginine metabolism, despite Cd2+ inhibition.
- Specific metabolic pathways for cysteine and its oxidized forms were identified, along with triggered intracellular mechanisms.
Conclusions:
- The study clarifies cysteine metabolism in Moorella thermoacetica within a biohybrid system.
- Intracellular storage and arginine metabolism play key roles in enhancing metabolic activity in CdS-containing cells.
- Understanding these mechanisms is crucial for optimizing biohybrid systems for bioenergy and compound production.
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