8S4E

Dimeric Alpha-beta barrel protein from Brassica rapa subsp.pekinensis

Summary for 8S4E

• Entry DOI: 10.2210/pdb8s4e/pdb
• Descriptor: Genome assembly, chromosome: A10 (2 entities in total)
• Functional Keywords: hydrolase, dimeric alpha-beta barrel protein
• Biological source: Brassica rapa (field mustard)
• Total number of polymer chains: 2
• Total formula weight: 27667.40

Authors

Pick, L.M.,Tang, Q.,Ansorge-Schumacher, M.,Grogan, G. (deposition date: 2024-02-21, release date: 2025-01-15)

Primary citation

Pick, L.M.,Oehme, V.,Hartmann, J.,Wenzlaff, J.,Tang, Q.,Grogan, G.,Ansorge-Schumacher, M.B.
SilE-R and SilE-S-DABB Proteins Catalying Enantiospecific Hydrolysis of Organosilyl Ethers.
Angew.Chem.Int.Ed.Engl., 63:e202404105-e202404105, 2024

PubMed Abstract: Silyl ethers fulfil a fundamental role in synthetic organic chemistry as protecting groups and their selective cleavage is an important factor in their application. We present here for the first time two enzymes, SilE-R and SilE-S, which are able to hydrolyse silyl ethers. They belong to the stress-response dimeric A/B barrel domain (DABB) family and are able to cleave the Si-O bond with opposite enantiopreference. Silyl ethers containing aromatic, cyclic or aliphatic alcohols and, depending on the alcohol moiety, silyl functions as large as TBDMS are accepted. The X-ray crystal structure of SilE-R, determined to a resolution of 1.98 Å, in combination with mutational studies, revealed an active site featuring two histidine residues, H8 and H79, which likely act synergistically as nucleophile and Brønsted base in the hydrolytic mechanism, which has not previously been described for enzymes. Although the natural function of SilE-R and SilE-S is unknown, we propose that these 'silyl etherases' may have significant potential for synthetic applications.

PubMed: 38630059
DOI: 10.1002/anie.202404105

Experimental method

X-RAY DIFFRACTION (1.98 Å)