Journalartikel

Jahr der Veröffentlichung: 2019

Seiten: 3728-3736

Zeitschrift: Environmental Microbiology

Bandnummer: 21

Heftnummer: 10

ISSN: 1462-2912

eISSN: 1462-2920

DOI Link: https://doi.org/10.1111/1462-2920.14720

Verlag: Wiley

Abstract: 
Acetogenic bacteria recently attracted attention because they reduce carbon dioxide (CO2) with hydrogen (H-2) to acetate or to other products such as ethanol. Besides gases, acetogens use a broad range of substrates, but conversion of the sugar alcohol mannitol has rarely been reported. We found that the thermophilic acetogenic bacterium Thermoanaerobacter kivui grew on mannitol with a specific growth rate of 0.33 h(-1) to a final optical density (OD600) of 2.2. Acetate was the major product formed. A lag phase was observed only in cultures pre-grown on glucose, not in those pre-grown on mannitol, indicating that mannitol metabolism is regulated. Mannitol-1-phosphate dehydrogenase (MtlD) activity was observed in cell-free extracts of cells grown on mannitol only. A gene cluster (TKV_c02830-TKV_c02860) for mannitol uptake and conversion was identified in the T. kivui genome, and its involvement was confirmed by deleting the mtlD gene (TKV_c02860) encoding the key enzyme MtlD. Finally, we overexpressed mtlD, and the recombinant MtlD carried out the reduction of fructose-6-phosphate with NADH, at a high V-MAX of 1235 U mg(-1) at 65 degrees C. The enzyme was thermostable for 40 min at 75 degrees C, thereby representing the first characterized MtlD from a thermophile.

Harvard-Zitierstil: Moon, J., Henke, L., Merz, N. and Basen, M. (2019) A thermostable mannitol-1-phosphate dehydrogenase is required in mannitol metabolism of the thermophilic acetogenic bacterium Thermoanaerobacter kivui, Environmental Microbiology, 21(10), pp. 3728-3736. https://doi.org/10.1111/1462-2920.14720

APA-Zitierstil: Moon, J., Henke, L., Merz, N., & Basen, M. (2019). A thermostable mannitol-1-phosphate dehydrogenase is required in mannitol metabolism of the thermophilic acetogenic bacterium Thermoanaerobacter kivui. Environmental Microbiology. 21(10), 3728-3736. https://doi.org/10.1111/1462-2920.14720