6 publications

6 publications

Covalent Anchoring of a Racemization Catalyst to CALB-Beads: Towards Dual Immobilization of DKR Catalysts

Klein Gebbink, R.J.M.; van Koten, G.

Tetrahedron Lett. 2011, 52, 1601-1604, 10.1016/j.tetlet.2011.01.106

The preparation of a heterogeneous bifunctional catalytic system, combining the catalytic properties of an organometallic catalyst (racemization) with those of an enzyme (enantioselective acylation) is described. A novel ruthenium phosphonate inhibitor was synthesized and covalently anchored to a lipase immobilized on a solid support (CALB, Novozym® 435). The immobilized bifunctional catalytic system showed activity in both racemization of (S)-1-phenylethanol and selective acylation of 1-phenylethanol.


Metal: Ru
Anchoring strategy: Covalent
Optimization: Chemical
Reaction: Acylation
Max TON: ---
ee: >99%
PDB: ---
Notes: Lipase CALB is immobilized on a solid support (Novozym®435). Dynamic kinetic resolution (DKR) of 1-phenylethanol to the acylated product.

Design and Evolution of New Catalytic Activity with an Existing Protein Scaffold

Kim, H.S.

Science 2006, 311, 535-538, 10.1126/science.1118953

The design of enzymes with new functions and properties has long been a goal in protein engineering. Here, we report a strategy to change the catalytic activity of an existing protein scaffold. This was achieved by simultaneous incorporation and adjustment of functional elements through insertion, deletion, and substitution of several active site loops, followed by point mutations to fine-tune the activity. Using this approach, we were able to introduce β-lactamase activity into the αβ/βα metallohydrolase scaffold of glyoxalase II. The resulting enzyme, evMBL8 (evolved metallo β-lactamase 8), completely lost its original activity and, instead, catalyzed the hydrolysis of cefotaxime with a (kcat /Km)app of 1.8 × 102 (mole/liter)–1 second–1, thus increasing resistance to Escherichia coli growth on cefotaxime by a factor of about 100.


Metal: Zn
Ligand type: Amino acid
Host protein: Glyoxalase II (Human)
Anchoring strategy: Dative
Optimization: Genetic
Max TON: ---
ee: ---
PDB: 2F50
Notes: kcat/KM ≈ 184 M-1*s-1

Metal-Mediated Protein Assembly Using a Genetically Incorporated Metal-Chelating Amino Acid

Kim, H.M.; Lee, H.S.

Biomacromolecules 2020, 21, 5021-5028, 10.1021/acs.biomac.0c01194

Many natural proteins function in oligomeric forms, which are critical for their sophisticated functions. The construction of protein assemblies has great potential for biosensors, enzyme catalysis, and biomedical applications. In designing protein assemblies, a critical process is to create protein–protein interaction (PPI) networks at defined sites of a target protein. Although a few methods are available for this purpose, most of them are dependent on existing PPIs of natural proteins to some extent. In this report, a metal-chelating amino acid, 2,2′-bipyridylalanine (BPA), was genetically introduced into defined sites of a monomeric protein and used to form protein oligomers. Depending on the number of BPAs introduced into the protein and the species of metal ions (Ni2+ and Cu2+), dimers or oligomers with different oligomerization patterns were formed by complexation with a metal ion. Oligomer sizes could also be controlled by incorporating two BPAs at different locations with varied angles to the center of the protein. When three BPAs were introduced, the monomeric protein formed a large complex with Ni2+. In addition, when Cu2+ was used for complex formation with the protein containing two BPAs, a linear complex was formed. The method proposed in this report is technically simple and generally applicable to various proteins with interesting functions. Therefore, this method would be useful for the design and construction of functional protein assemblies.


Metal: Cu; Ni
Ligand type: Bipyridine
Anchoring strategy: Dative
Optimization: ---
Reaction: ---
Max TON: ---
ee: ---
PDB: ---
Notes: ---

Rare Earth Metal Ions as Probes of Calcium Binding Sites in Proteins: Neodynium Acceleration of the Activation of Trypsinogen

Birnbaum, E.R.; Darnall, D.W.

J. Biol. Chem. 1970, n/a

The rate of activation of the conversion of trypsinogen to trypsin has been found to be greatly accelerated by the neodymium(III) ion. The similarity of this process to the calcium(II) ion activation suggests that both metal ions bind at identical sites in trypsinogen. The rate of activation in the presence of the neodymium ion is much greater than that of the calcium ion, probably reflecting the increased stability constant of the neodymium-protein complex. In contrast to the calcium ion, however, neodymium(III) can be scrutinized by a variety of spectral and magnetic techniques which should reveal information concerning the calcium ion binding sites in proteins. Since the chemistry and the range of sires of the rare earth metal ions are so similar to that of the calcium ion, it is suggested that generally these ions should make good replacement ions for probing the calcium ion binding sites of proteins and enzymes.


Metal: Nd
Ligand type: Amino acid
Host protein: Trypsin
Anchoring strategy: Metal substitution
Optimization: ---
Max TON: <1
ee: ---
PDB: ---
Notes: PMID 5484822

Semisynthesis of Bipyridyl-Alanine Cytochrome c Mutants: Novel Proteins with Enhanced Electron-Transfer Properties

Gray, H.B.; Imperiali, B.

J. Am. Chem. Soc. 1993, 115, 8455-8456, 10.1021/ja00071a068

n/a


Metal: Fe; Ru
Ligand type: Bipyridine; Porphyrin
Host protein: Horse heart cytochrome c
Anchoring strategy: Covalent
Optimization: ---
Reaction: Electron transfer
Max TON: ---
ee: ---
PDB: ---
Notes: No catalysis

The Bovine Serum Albumin-2-Phenylpropane-1,2-diolatodioxoosmium(VI) Complex as an Enantioselective Catalyst for cis-Hydroxylation of Alkenes

Kokubo, T.; Okano, M.

J. Chem. Soc., Chem. Commun. 1983, 0, 769-770, 10.1039/C39830000769

The 1:1 complex between an osmate ester and bovine serum albumin was found to be effective as an enantioselective catalyst in the cis-hydroxylation of alkenes, affording diols in up to 68% e.e. and turnover of the catalyst with t-butyl hydroperoxide.


Metal: Os
Ligand type: Undefined
Anchoring strategy: Undefined
Optimization: ---
Reaction: Dihydroxylation
Max TON: 40
ee: 68
PDB: ---
Notes: ---