7QE1

Crystal structure of apo SN243

Summary for 7QE1

• Entry DOI: 10.2210/pdb7qe1/pdb
• Descriptor: SN243, ZINC ION (3 entities in total)
• Functional Keywords: enzyme discovery, carbohydrate-active enzymes (cazy), protein engineering, functional metagenomics), hydrolase
• Biological source: unidentified
• Total number of polymer chains: 2
• Total formula weight: 165599.75

Authors

Neun, S.,Brear, P.,Campbell, E.,Omari, K.,Wagner, O.,Hyvonen, M.,Hollfelder, F. (deposition date: 2021-12-01, release date: 2022-10-12, Last modification date: 2024-11-06)

Primary citation

Neun, S.,Brear, P.,Campbell, E.,Tryfona, T.,El Omari, K.,Wagner, A.,Dupree, P.,Hyvonen, M.,Hollfelder, F.
Functional metagenomic screening identifies an unexpected beta-glucuronidase.
Nat.Chem.Biol., 18:1096-1103, 2022

PubMed Abstract: The abundance of recorded protein sequence data stands in contrast to the small number of experimentally verified functional annotation. Here we screened a million-membered metagenomic library at ultrahigh throughput in microfluidic droplets for β-glucuronidase activity. We identified SN243, a genuine β-glucuronidase with little homology to previously studied enzymes of this type, as a glycoside hydrolase 3 family member. This glycoside hydrolase family contains only one recently added β-glucuronidase, showing that a functional metagenomic approach can shed light on assignments that are currently 'unpredictable' by bioinformatics. Kinetic analyses of SN243 characterized it as a promiscuous catalyst and structural analysis suggests regions of divergence from homologous glycoside hydrolase 3 members creating a wide-open active site. With a screening throughput of >10 library members per day, picolitre-volume microfluidic droplets enable functional assignments that complement current enzyme database dictionaries and provide bridgeheads for the annotation of unexplored sequence space.

PubMed: 35799064
DOI: 10.1038/s41589-022-01071-x

Experimental method

X-RAY DIFFRACTION (1.95 Å)