Complex pectin metabolism by gut bacteria reveals novel catalytic functions

Abstract

Specificity of enzymes that cleave RG-II Each glycosidic linkage in RG-II, except for 2-O-methyl-D-xylosea1,3-L-fucose, is hydrolysed by a bespoke enzyme (Figs 1 and 2b). [...]although the loci encode multiple a-L-rhamnosidases and L-arabinosidases, there is no redundancy in the linkage hydrolysed by these enzymes (Supplementary Tables 2 and 3). The crystal structure of BT1020 (Extended Data Fig. 4a) reveals an N-terminal 5-bladed ß-propeller that displays 2-keto-3-deoxy-D-/yxo-heptulosaric acid (DHA)-hydrolase activity and a C-terminal (a/a)6-barrel ß-L-arabinofuranosidase.