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Enzyme Activity by Design: an Artificial Rhodium

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Enzyme Activity by Design: an Artificial Rhodium Edinburgh Research Explorer Enzyme Activity by Design: An Artificial Rhodium Hydroformylase for Linear Aldehydes Citation for published version: Jarvis, AG, Obrecht, L, Deuss, PJ, Laan, W, Gibson, EK, Wells, PP & Kamer, PCJ 2017, 'Enzyme Activity by Design: An Artificial Rhodium Hydroformylase for Linear Aldehydes', Angewandte Chemie International Edition, vol. 56, no. 44, pp. 13596-13600. https://doi.org/10.1002/anie.201705753 Digital Object Identifier (DOI): 10.1002/anie.201705753 Link: Link to publication record in Edinburgh Research Explorer Document Version: Publisher's PDF, also known as Version of record Published In: Angewandte Chemie International Edition General rights Copyright for the publications made accessible via the Edinburgh Research Explorer is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. Take down policy The University of Edinburgh has made every reasonable effort to ensure that Edinburgh Research Explorer content complies with UK legislation. If you believe that the public display of this file breaches copyright please contact [email protected] providing details, and we will remove access to the work immediately and investigate your claim. Download date: 10. Oct. 2021 Angewandte Communications Chemie International Edition:DOI:10.1002/anie.201705753 Catalyst Design Very Important Paper German Edition:DOI:10.1002/ange.201705753 Enzyme Activity by Design:AnArtificial Rhodium Hydroformylase for Linear Aldehydes Amanda G. Jarvis,* Lorenz Obrecht, Peter J. Deuss,Wouter Laan, Emma K. Gibson, Peter P. Wells,and Paul C. J. Kamer* Abstract: Artificial metalloenzymes (ArMs) are hybrid cata- rates and performances achieved by natural enzymes.[3] In lysts that offer aunique opportunity to combine the superior addition, the molecular recognition and shape selectivity of performance of natural protein structures with the unnatural proteins have typically not been exploited. Themost success- reactivity of transition-metal catalytic centers.Therefore,they ful approach to create ArMs has been the use of non-covalent providethe prospect of highly selective and active catalytic anchoring strategies utilizing protein scaffolds with strong chemical conversions for whichnatural enzymes are unavail- supramolecular recognition motifs such as avidin.[4] In these able.Herein, we show how by rationally combining robust site- ArMs,the binding site is used to carry the active metal center specific phosphine bioconjugation methods and alipid-bind- or bind metal-containing cofactors,restricting the possible ing protein (SCP-2L), an artificial rhodium hydroformylase applications of the binding properties of the protein. An was developed that displays remarkable activities and selectiv- alternative approach utilizes site-selective protein modifica- ities for the biphasic production of long-chain linear aldehydes tion methods[5] to incorporate transition metals into awide under benign aqueous conditions.Overall, this study demon- range of protein scaffolds whilst leaving the proteinsinnate strates that judiciously chosen protein-binding scaffolds can be binding capabilities largely intact. Any protein scaffold can be adapted to obtain metalloenzymes that provide the reactivity of used, allowing the exploitation of the almost unlimited range the introduced metal center combined with specifically of highly specific substrate-binding capabilities of proteins. intended product selectivity. Therefore,virtually any organometallic non-natural catalytic reaction can be merged with the sophisticated biological The development of substrate- and product-specific catalytic performance of enzymes,and this approach offers significant processes that operate efficiently at mild reaction temper- opportunities for the design of ArMs aiming at high atures is amajor challenge for the synthetic chemistry selectivity by shape-selective product formation. Herein, we community.[1] Enzymes are naturesmain catalysts and demonstrate the potential of such ArMs through the develop- catalyze numerous chemical transformations,typically under ment of artificial rhodium enzymes derived from aprotein benign conditions.However,many desired chemical reactions scaffold that was selected for its apolar substrate-binding are not performed by nature,and therefore,there are no properties.These ArMs enable selective aldehyde formation suitable natural enzymes.Artificial metalloenzymes (ArMs) in the biphasic hydroformylation of long-chain linear alkenes, provide away to bridge that gap between natural and areaction for which no natural enzymes are known, and chemical synthesis,providing enzymes for unnatural reac- which is challenged in current industrial applications by the tions.[2] Despite these successes,most ArMs do not meet the low solubility of the substrates in the aqueous phase.[6] [*] Dr.A.G.Jarvis, Dr.L.Obrecht, Dr.P.J.Deuss, Dr.W.Laan, and Prof. P. C. J. Kamer Diamond Light Source, Harwell Science & Innovation Campus School of Chemistry,University of St Andrews Didcot, Oxfordshire, OX11 0DE (UK) North Haugh, St Andrews,Fife, KY16 9ST (UK) Prof. P. C. J. Kamer E-mail:[email protected] Bioinspired Homo- & HeterogeneousCatalysis Dr.P.J.Deuss Leibniz Institute for Catalysis Department of Chemical Engineering (ENTEG) Albert-Einstein-Strasse 29a, 18059 Rostock (Germany) UniversityofGroningen E-mail:[email protected] Nijenborgh 4, 9747 AG Groningen (The Netherlands) Dr.W.Laan Dr.E.K.Gibson Current address:Phoreon, Bioincubator I Department of Chemistry,University College London Gaston Geenslaan 1, 3001 Leuven (Belgium) 20 Gordon Street, London WC1H 0AJ (UK) Supportinginformation and the ORCID identification number(s) for Dr.E.K.Gibson, Dr.P.P.Wells the author(s) of this article can be found under: UK Catalysis Hub, Research Complex at Harwell https://doi.org/10.1002/anie.201705753. Research data supporting Rutherford Appleton Laboratory this publicationcan be accessed at DOI:10.17630/03fa38f2-b858- Harwell Science & Innovation Campus 4fff-a478-83e61672955c. Didcot, Oxfordshire, OX11 0FA (UK) 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. Dr.P.P.Wells KGaA. This is an open access article under the terms of the Creative School of Chemistry,University of Southampton Commons AttributionLicense, which permits use, distribution and Southampton, SO17 1BJ (UK) reproduction in any medium, provided the original work is properly cited. 13596 2017 The Authors. Published by Wiley-VCH Verlag GmbH &Co. KGaA, Weinheim Angew.Chem.Int. Ed. 2017, 56,13596 –13600 Angewandte Communications Chemie Scheme 1. A) Synthesis of the artificialmetalloproteins. B) Hydrofor- mylation of 1-octene. AA = amino acid. Figure 1. A) The use of the apolar tunnel to introduce regioselectivity We have previously reported amethod that enables such into hydroformylation. B) The apolar tunnel in SCP-2L, showing the an approach for the synthesis of ArMs containing metal- position of Triton X-100 in the tunnel in the original crystal structure binding phosphine ligands (Scheme 1A).[5a,7] Rhodium–phos- (PDB No. 1IKT),[13] the tunnel dimensions, and the positions of A100 phine complexes are known to be highly active and robust and V83. hydroformylation catalysts,and thus our strategy provides the prospect of enzymatic hydroformylation reactions.Rhodium– protein hybrids tested to date in hydroformylation have linear product (Figure 1A). To introduce the catalytic rho- utilized dative protein–rhodium interactions with limited dium–phosphine complexes,two mutants containing unique success.[8] Although this has led to unprecedented linear cysteines at either end of the tunnel were prepared (SCP-2L selectivities for the hydroformylation of styrene,[9] theexact V83C and SCP-2L A100C;Figure 1B).[5a,14] These two nature of the active species,and thus the origin of the mutants,obtained in excellent yields,showed little structural selectivity,isstill unclear.[10] Rhodium-catalyzed hydroformy- permutations and similar aliphatic substrate binding capabil- lation is used on a800000 ton scale to produce butyraldehyde ities as the wild-type (WT) protein (see the Supporting from propene under biphasic conditions,[11] allowing for the Information, Table S3). Both SCP-2L mutants were success- recovery of the expensive rhodium 3,3’,3’’-phosphanetriyl- fully modified with aldehyde phosphines P1–P3 through tris(benzenesulfonic acid) trisodium salt catalyst (Rh/ acysteine modification strategy (Scheme 1A;for character- TPPTS). Long-chain aldehydes are desired by industry as ization data for SCP-2L V83C–1–(P1–P3), see Ref.[5a];for they are important precursors for the production of deter- SCP-2L A100C–1–(P1–P3), see the Supporting Information). gents and plasticizers.[12] This process is not feasible for long- Therhodium proteins (SCP-2LV83C/A100C–1–(P1–P3)– chain alkenes (> 5Catoms) owing to their low solubility in Rh) were obtained by the addition of Rh(acac)(CO)2.Other water.[6] Rh precursors did not selectively bind to the phosphine (see Fatty acid transporter proteins contain apolar tunnels and Table S4 for MS and metal loading analysis). Their catalytic clefts to bind their hydrophobic cargo.The steroid carrier activity was investigated in the hydroformylation of 1-octene protein type 2like (SCP-2L) domain of the human multi- at 358Cand 80 bar synthesis gas (Figure 2, Scheme 1B,and functional enzyme 2(MFE-2) was identified as asuitable Table S5). To minimize
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