Abstract
Using the hydrolysis of epoxides in water as a model reaction, the effect of multiple active sites on Michaelis-Menten compliant rate accelerations in a porous capsule is demonstrated. The capsule is a water-soluble Ih-symmetry Keplerate-type complex of the form, [{MoVI6O21(H2O)6}12{MoV2O4(L)}30]42-, in which 12 pentagonal "ligands," {(MoVI)MoVI5O21(H2O)6}6-, are coordinated to 30 dimolybdenum sites, {MoV2O4L}1+ (L = an endohedrally coordinated ν2-bound carboxylate anion), resulting in 20 Mo9O9 pores. When "up-regulated" by removal of ca. one-third of the blocking ligands, L, an equal number of dimolybdenum sites are activated, and the newly freed-up space allows for encapsulation of nearly twice as many substrate guests, leading to a larger effective molarity (amplification), and an increase in the rate acceleration (kcat/kuncat) from 16,000 to an enzyme-like value of 182,800.
Original language | American English |
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Pages (from-to) | 12740-12743 |
Number of pages | 4 |
Journal | Journal of the American Chemical Society |
Volume | 137 |
Issue number | 40 |
DOIs | |
State | Published - 14 Oct 2015 |
All Science Journal Classification (ASJC) codes
- General Chemistry
- Biochemistry
- Catalysis
- Colloid and Surface Chemistry