1,6-α-L-Fucosidases from <i>Bifidobacterium</i> <i>longum</i> subsp. <i>infantis</i> ATCC 15697 Involved in the Degradation of Core-fucosylated <i>N</i>-Glycan
Hisashi Ashida, Taku Fujimoto, Shin Kurihara, Masayuki Nakamura, Masahiro Komeno, Yibo Huang, Takane Katayama, Takashi Kinoshita, Kaoru Takegawa
Abstract
Bifidobacterium longum subsp. infantis ATCC 15697 possesses five -L-fucosidases, which have been previously characterized toward fucosylated human milk oligosaccharides containing 1,2/3/4-linked fucose [Sela et al.: Appl. Environ. Microbiol., 78, 795-803 (2012)]. In this study, two glycoside hydrolase family 29 -L-fucosidases out of five (Blon_0426 and Blon_0248) were found to be 1,6--L-fucosidases acting on core 1,6-fucose on the N-glycan of glycoproteins. These enzymes readily hydrolyzed p-nitrophenyl--L-fucoside and Fuc1-6GlcNAc, but hardly hydrolyzed Fuc1-6(GlcNAc1-4)GlcNAc, suggesting that they de-fucosylate Fuc1-6GlcNAc1-Asn-peptides/ proteins generated by the action of endo--N-acetylglucosaminidase. We demonstrated that Blon_0426 can de-fucosylate Fuc1-6GlcNAc-IgG prepared from Rituximab using Endo-CoM from Cordyceps militaris. To generate homogenous non-fucosylated N-glycan-containing IgG with high antibodydependent cellular cytotoxicity (ADCC) activity, the resulting GlcNAc-IgG has a potential to be a good acceptor substrate for the glycosynthase mutant of Endo-M from Mucor hiemalis. Collectively, our results strongly suggest that Blon_0426 and Blon_0248 are useful for glycoprotein glycan remodeling.