6k1g

Publication Abstract from PubMed

Background: l-Fucose is a rare sugar with potential uses in the pharmaceutical, cosmetic, and food industries. The enzymatic approach using l-fucose isomerase, which interconverts l-fucose and l-fuculose, can be an efficient way of producing l-fucose for industrial applications. Here, we performed biochemical and structural analyses of l-fucose isomerase identified from a novel species of Raoultella (RdFucI). Results: RdFucI exhibited higher enzymatic activity for l-fuculose than for l-fucose, and the rate for the reverse reaction of converting l-fuculose to l-fucose was higher than that for the forward reaction of converting l-fucose to l-fuculose. In the equilibrium mixture, a much higher proportion of l-fucose (~ ninefold) was achieved at 30 degrees C and pH 7, indicating that the enzyme-catalyzed reaction favors the formation of l-fucose from l-fuculose. When biochemical analysis was conducted using l-fuculose as the substrate, the optimal conditions for RdFucI activity were determined to be 40 degrees C and pH 10. However, the equilibrium composition was not affected by reaction temperature in the range of 30 to 50 degrees C. Furthermore, RdFucI was found to be a metalloenzyme requiring Mn(2+) as a cofactor. The comparative crystal structural analysis of RdFucI revealed the distinct conformation of alpha7-alpha8 loop of RdFucI. The loop is present at the entry of the substrate binding pocket and may affect the catalytic activity. Conclusions: RdFucI-catalyzed isomerization favored the reaction from l-fuculose to l-fucose. The biochemical and structural data of RdFucI will be helpful for the better understanding of the molecular mechanism of l-FucIs and the industrial production of l-fucose.

Enzymatic synthesis of l-fucose from l-fuculose using a fucose isomerase from Raoultella sp. and the biochemical and structural analyses of the enzyme.,Kim IJ, Kim DH, Nam KH, Kim KH Biotechnol Biofuels. 2019 Dec 5;12:282. doi: 10.1186/s13068-019-1619-0., eCollection 2019. PMID:31827610^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.