The first structure-function study of GH151 α-l-fucosidase uncovers new oligomerization pattern, active site...

Area of Science:

• Biochemistry
• Structural Biology
• Enzymology

Background:

• Fucosylated compounds are vital in biological processes, with potential applications in medicine and biotechnology.
• Glycosyl hydrolases, like alpha-L-fucosidase, show promise for modifying these compounds.
• The GH151 family of glycoside hydrolases remains largely uncharacterized, lacking structural and functional data.

Purpose of the Study:

• To present the first structure-function study of a GH151 family member.
• To elucidate the oligomerization, active site properties, and substrate selectivity of this enzyme.
• To provide insights into the unique features of GH151 alpha-L-fucosidases.

Main Methods:

• X-ray crystallography to determine the 3D structure.
• Small-angle X-ray scattering (SAXS) to analyze oligomerization.
• Site-directed mutagenesis and catalytic activity assays to investigate function.

Main Results:

• The enzyme functions as a novel tetramer, a previously unreported oligomerization state for this family.
• Active site complementation was observed, with histidine 503 playing a critical role, confirmed by mutagenesis.
• Unique features including substrate selectivity and active site accessibility were identified.

Conclusions:

• This study provides the first structural and functional insights into the GH151 alpha-L-fucosidase family.
• The enzyme's tetrameric structure and active site complementation mechanism are key to its function.
• Findings pave the way for targeted engineering of GH151 enzymes for biotechnological applications.