Faculty Opinions recommendation of Computational prediction of structure, substrate binding mode, mechanism, and rate for a malaria protease with a novel type of active site.

Author(s):  
Arieh Warshel
Biochemistry ◽  
2007 ◽  
Vol 46 (44) ◽  
pp. 12628-12638 ◽  
Author(s):  
Feng Yan ◽  
Sung-Ju Moon ◽  
Pinghua Liu ◽  
Zongbao Zhao ◽  
John D. Lipscomb ◽  
...  

2004 ◽  
Vol 380 (2) ◽  
pp. 339-346 ◽  
Author(s):  
Young Sam SEO ◽  
Ahrim YOO ◽  
Jinwon JUNG ◽  
Soon-Kee SUNG ◽  
Dae Ryook YANG ◽  
...  

The active site and substrate-binding mode of MD-ACO1 (Malus domestica Borkh. 1-aminocyclopropane-1-carboxylate oxidase) have been determined using site-directed mutagenesis and comparative modelling methods. The MD-ACO1 protein folds into a compact jelly-roll motif comprised of eight α-helices, 12 β-strands and several long loops. The active site is well defined as a wide cleft near the C-terminus. The co-substrate ascorbate is located in cofactor Fe2+-binding pocket, the so-called ‘2-His-1-carboxylate facial triad’. In addition, our results reveal that Arg244 and Ser246 are involved in generating the reaction product during enzyme catalysis. The structure agrees well with the biochemical and site-directed mutagenesis results. The three-dimensional structure together with the steady-state kinetics of both the wild-type and mutant MD-ACO1 proteins reveal how the substrate specificity of MD-ACO1 is involved in the catalytic mechanism, providing insights into understanding the fruit ripening process at atomic resolution.


1993 ◽  
Vol 212 (1) ◽  
pp. 151-156 ◽  
Author(s):  
Izumi KUMAGAI ◽  
Katsumi MAENAKA ◽  
Futoshi SUNADA ◽  
Shigeki TAKEDA ◽  
Kin-ichiro MIURA

2021 ◽  
Vol 22 (23) ◽  
pp. 12624
Author(s):  
Léa El Khoury ◽  
David L. Mobley ◽  
Dongmei Ye ◽  
Susan B. Rempe

Organophosphorus hydrolase (OPH) is a metalloenzyme that can hydrolyze organophosphorus agents resulting in products that are generally of reduced toxicity. The best OPH substrate found to date is diethyl p-nitrophenyl phosphate (paraoxon). Most structural and kinetic studies assume that the binding orientation of paraoxon is identical to that of diethyl 4-methylbenzylphosphonate, which is the only substrate analog co-crystallized with OPH. In the current work, we used a combined docking and molecular dynamics (MD) approach to predict the likely binding mode of paraoxon. Then, we used the predicted binding mode to run MD simulations on the wild type (WT) OPH complexed with paraoxon, and OPH mutants complexed with paraoxon. Additionally, we identified three hot-spot residues (D253, H254, and I255) involved in the stability of the OPH active site. We then experimentally assayed single and double mutants involving these residues for paraoxon binding affinity. The binding free energy calculations and the experimental kinetics of the reactions between each OPH mutant and paraoxon show that mutated forms D253E, D253E-H254R, and D253E-I255G exhibit enhanced substrate binding affinity over WT OPH. Interestingly, our experimental results show that the substrate binding affinity of the double mutant D253E-H254R increased by 19-fold compared to WT OPH.


2018 ◽  
Vol 46 (6) ◽  
pp. 1431-1447 ◽  
Author(s):  
Tobias Tandrup ◽  
Kristian E. H. Frandsen ◽  
Katja S. Johansen ◽  
Jean-Guy Berrin ◽  
Leila Lo Leggio

Lytic polysaccharide monooxygenases (LPMOs) are copper enzymes discovered within the last 10 years. By degrading recalcitrant substrates oxidatively, these enzymes are major contributors to the recycling of carbon in nature and are being used in the biorefinery industry. Recently, two new families of LPMOs have been defined and structurally characterized, AA14 and AA15, sharing many of previously found structural features. However, unlike most LPMOs to date, AA14 degrades xylan in the context of complex substrates, while AA15 is particularly interesting because they expand the presence of LPMOs from the predominantly microbial to the animal kingdom. The first two neutron crystallography structures have been determined, which, together with high-resolution room temperature X-ray structures, have putatively identified oxygen species at or near the active site of LPMOs. Many recent computational and experimental studies have also investigated the mechanism of action and substrate-binding mode of LPMOs. Perhaps, the most significant recent advance is the increasing structural and biochemical evidence, suggesting that LPMOs follow different mechanistic pathways with different substrates, co-substrates and reductants, by behaving as monooxygenases or peroxygenases with molecular oxygen or hydrogen peroxide as a co-substrate, respectively.


Sign in / Sign up

Export Citation Format

Share Document