scholarly journals Quantum Effects on H2 Diffusion in Zeolite RHO: Inverse Kinetic Isotope Effect for Sieving

2019 ◽  
Vol 141 (34) ◽  
pp. 13635-13642 ◽  
Author(s):  
Lu Gem Gao ◽  
Rui Ming Zhang ◽  
Xuefei Xu ◽  
Donald G. Truhlar
Keyword(s):  
Isotope Effect ◽  
Kinetic Isotope Effect ◽  
Quantum Effects ◽  
Kinetic Isotope ◽  
Zeolite Rho

Nuclear quantum effects in enzymatic reactions: simulation of the kinetic isotope effect of phenylethylamine oxidation catalyzed by monoamine oxidase A

2020 ◽  
Vol 22 (13) ◽  
pp. 6838-6847 ◽  
Author(s):  
Alja Prah ◽  
Peter Ogrin ◽  
Janez Mavri ◽  
Jernej Stare
Keyword(s):  
Monoamine Oxidase ◽  
Isotope Effect ◽  
Kinetic Isotope Effect ◽  
Quantum Effects ◽  
Monoamine Oxidase A ◽  
Computational Techniques ◽  
Nuclear Motion ◽  
Enzymatic Reactions ◽  
Kinetic Isotope ◽  
Nuclear Quantum Effects

By using computational techniques for quantizing nuclear motion one can accurately reproduce kinetic isotope effect of enzymatic reactions, as demonstrated for phenylethylamine oxidation catalyzed by the monoamine oxidase A enzyme.

Quantum electrocatalysts: theoretical picture, electrochemical kinetic isotope effect analysis, and conjecture to understand microscopic mechanisms

2020 ◽  
Vol 22 (20) ◽  
pp. 11219-11243 ◽  
Author(s):  
Ken Sakaushi
Keyword(s):  
Isotope Effect ◽  
Kinetic Isotope Effect ◽  
Effect Analysis ◽  
Kinetic Isotope

The fundamental aspects of quantum electrocatalysts are discussed together with the newly developed electrochemical kinetic isotope effect (EC-KIE) approach.

scholarly journals l-mandelate dehydrogenase from Rhodotorula graminis: comparisons with the l-lactate dehydrogenase (flavocytochrome b2) from Saccharomyces cerevisiae

1993 ◽  
Vol 290 (1) ◽  
pp. 103-107 ◽  
Author(s):  
O Smékal ◽  
M Yasin ◽  
C A Fewson ◽  
G A Reid ◽  
S K Chapman
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Lactate Dehydrogenase ◽  
Isotope Effect ◽  
Kinetic Isotope Effect ◽  
Dimensional Structure ◽  
Striking Difference ◽  
Kinetic Properties ◽  
Proton Abstraction ◽  
Rate Determining Step ◽  
Kinetic Isotope

L-Lactate dehydrogenase (L-LDH) from Saccharomyces cerevisiae and L-mandelate dehydrogenase (L-MDH) from Rhodotorula graminis are both flavocytochromes b2. The kinetic properties of these enzymes have been compared using steady-state kinetic methods. The most striking difference between the two enzymes is found by comparing their substrate specificities. L-LDH and L-MDH have mutually exclusive primary substrates, i.e. the substrate for one enzyme is a potent competitive inhibitor for the other. Molecular-modelling studies on the known three-dimensional structure of S. cerevisiae L-LDH suggest that this enzyme is unable to catalyse the oxidation of L-mandelate because productive binding is impeded by steric interference, particularly between the side chain of Leu-230 and the phenyl ring of mandelate. Another major difference between L-LDH and L-MDH lies in the rate-determining step. For S. cerevisiae L-LDH, the major rate-determining step is proton abstraction at C-2 of lactate, as previously shown by the 2H kinetic-isotope effect. However, in R. graminis L-MDH the kinetic-isotope effect seen with DL-[2-2H]mandelate is only 1.1 +/- 0.1, clearly showing that proton abstraction at C-2 of mandelate is not rate-limiting. The fact that the rate-determining step is different indicates that the transition states in each of these enzymes must also be different.

Isotope effect profiles in the N-demethylation of N,N-dimethylanilines: a key to determine the pKa of nonheme Fe(iii)–OH complexes

2015 ◽  
Vol 51 (24) ◽  
pp. 5032-5035 ◽  
Author(s):  
Alessia Barbieri ◽  
Martina De Gennaro ◽  
Stefano Di Stefano ◽  
Osvaldo Lanzalunga ◽  
Andrea Lapi ◽  
...  
Keyword(s):  
Isotope Effect ◽  
Kinetic Isotope Effect ◽  
Kinetic Isotope

pKa of [(N4Py)FeIII–OH]2+ is obtained from the kinetic isotope effect profiles in the N-demethylation of N,N-dimethylanilines promoted by [(N4Py)FeIVO]2+.

Sign in / Sign up

Export Citation Format

Share Document