Functional and structural characterization of AtAbf43C: an exo-1,5-α-L-arabinofuranosidase from Acetivibrio thermocellus DSM1313.

ABSTRACT: Acetivibrio thermocellus degrades diverse polysaccharides found in plant biomass using an array of glycoside hydrolase (GH) enzymes. Here, we describe the structure and function of AtAbf43C, an uncharacterized GH family 43 subfamily 26 (GH43_26) α-L-arabinofuranosidase (EC 3.2.1.55) from A. thermocellus. AtAbf43C is optimally active on para-nitrophenol-α-L-arabinofuranoside at pH 5.5 and 65 °C, making it the most thermophilic bacterial GH43_26 enzyme characterized to date. We solved high-resolution crystal structures of full-length AtAbf43C and its individual carbohydrate binding module family 42 (CBM42) and GH43 domains, including a structure with L-arabinofuranose molecules bound to the CBM42. The CBM42 domain adopts a typical β-trefoil fold, and the GH43 domain forms a canonical 5-blade

SUBMITTER: Galindo JL 

PROVIDER: S-EPMC12493170 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature