The role of streptavidin and its variants in catalysis by biotinylated secondary amines

DOI: 10.1039/D1OB01947C

Authors: Alexander R. Nödling (Cardiff University) , Nicolò Santi (Cardiff University) , Raquel Castillo (Universitat Jaume I) , Magdalena Lipka-Lloyd (Cardiff University) , Yi Jin (Cardiff University) , Louis C. Morrill (Cardiff University) , Katarzyna Świderek (Universitat Jaume I) , Vicent Moliner (Universitat Jaume I) , Louis Y. P. Luk (Cardiff University)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Organic & Biomolecular Chemistry , VOL 19 , PAGES 10424 - 10431

State: Published (Approved)
Published: November 2021
Diamond Proposal Number(s): 14843 , 18812

Abstract: Here, we combine the use of host screening, protein crystallography and QM/MM molecular dynamics simulations to investigate how the protein structure affects iminium catalysis by biotinylated secondary amines in a model 1,4 conjugate addition reaction. Monomeric streptavidin (M-Sav) lacks a quaternary structure and the solvent-exposed reaction site resulted in poor product conversion in the model reaction with low enantio- and regioselectivities. These parameters were much improved when the tetrameric host T-Sav was used; indeed, residues at the symmetrical subunit interface were proven to be critical for catalysis through a mutagenesis study. The use of QM/MM simulations and the asymmetric dimeric variant D-Sav revealed that both Lys121 residues which are located in the hosting and neighboring subunits play a critical role in controlling the stereoselectivity and reactivity. Lastly, the D-Sav template, though providing a lower conversion than that of the symmetric tetrameric counterpart, is likely a better starting point for future protein engineering because each surrounding residue within the asymmetric scaffold can be refined for secondary amine catalysis.

Diamond Keywords: Enzymes

Subject Areas: Biology and Bio-materials, Chemistry


Instruments: I03-Macromolecular Crystallography , I04-Macromolecular Crystallography

Added On: 14/03/2022 08:42

Documents:
d1ob01947c.pdf

Discipline Tags:

Biochemistry Catalysis Chemistry Structural biology Life Sciences & Biotech

Technical Tags:

Diffraction Macromolecular Crystallography (MX)