AUTHOR=Kim Heji , Mi Huynh Thi Ngoc , Ahn Joong-Hoon , Lee Jong Suk , Eser Bekir Engin , Choi Jongkeun , Han Jaehong 

TITLE=Glycoside-metabolizing oxidoreductase D3dgpA from human gut bacterium

JOURNAL=Frontiers in Bioengineering and Biotechnology

VOLUME=12

YEAR=2024

URL=https://www.frontiersin.org/journals/bioengineering-and-biotechnology/articles/10.3389/fbioe.2024.1413854

DOI=10.3389/fbioe.2024.1413854

ISSN=2296-4185

ABSTRACT=<p>The Gfo/Idh/MocA family enzyme DgpA was known to catalyze the regiospecific oxidation of puerarin to 3”-oxo-puerarin in the presence of 3-oxo-glucose. Here, we discovered that D3dgpA, <italic>dgpA</italic> cloned from the human gut bacterium <italic>Dorea</italic> sp. MRG-IFC3, catalyzed the regiospecific oxidation of various <italic>C</italic>-/<italic>O</italic>-glycosides, including puerarin, in the presence of methyl β-D-3-oxo-glucopyranoside. While <italic>C</italic>-glycosides were converted to 3”- and 2”-oxo-products by D3dgpA, <italic>O</italic>-glycosides resulted in the formation of aglycones and hexose enediolone from the 3”-oxo-products. From DFT calculations, it was found that isomerization of 3”-oxo-puerarin to 2”-oxo-puerarin required a small activation energy of 9.86 kcal/mol, and the <italic>O</italic>-glycosidic bond cleavage of 3”-oxo-products was also thermodynamically favored with a small activation energy of 3.49 kcal/mol. In addition, the reaction mechanism of D3dgpA was discussed in comparison to those of Gfo/Idh/MocA and GMC family enzymes. The robust reactivity of D3dgpA was proposed as a new general route for derivatization of glycosides.</p>