Substrate recognition mode of a glycoside hydrolase family 42 β-galactosidase from Bifidobacterium longum subspecies infantis (BiBga42A) revealed by crystallographic and mutational analyses.

ABSTRACT: Aim: Bifidobacterium longum subsp. infantis uses a glycoside hydrolase (GH) family 42 β-galactosidase (BiBga42A) for hydrolyzing lacto-N-tetraose (LNT), which is the most abundant core structure of human milk oligosaccharides (HMOs). As such, BiBga42A represents one of the pivotal enzymes underpinning the symbiosis between bifidobacteria and breastfed infants. Despite its importance, the structural basis underlying LNT hydrolysis by BiBga42A is not understood. Moreover, no substrate-complexed structures are available to date for GH42 family members. Methods: X-ray crystallography was used to determine the structures of BiBga42A in the apo- and liganded forms. The roles of the amino acid residues that were presumed to be involve

SUBMITTER: Gotoh A 

PROVIDER: S-EPMC10688820 | biostudies-literature | 2023

REPOSITORIES: biostudies-literature