Elucidation of spore-photoproduct formation by isotope labeling.
- Geng-min Lin, Lei Li
- ChemistryAngewandte Chemie
- 17 December 2010
Although SP was discovered nearly half a century ago, and despite the strong interest of the scientific community in how it is formed, little is known about the mechanism of spore-DNA photochemistry.
Chemical synthesis, crystal structure and enzymatic evaluation of a dinucleotide spore photoproduct analogue containing a formacetal linker.
- Geng-min Lin, Chun-Hsing Chen, M. Pink, J. Pu, Lei Li
- Chemistry, BiologyChemistry
- 22 August 2011
ROESY spectroscopic, DFT computational, and enzymatic studies of this 5R-CH(2) SP compound prove that it possesses similar properties with the5R-SP species, suggesting that the revealed structure truly reflects that of SP generated in Nature.
Structure, mechanism, and conformational dynamics of O-acetylserine sulfhydrylase from Salmonella typhimurium: comparison of A and B isozymes.
- A. Chattopadhyay, M. Meier, P. Cook
- Chemistry, BiologyBiochemistry
- 21 June 2007
Two isozymes found in Salmonella typhimurium show a different equilibrium distribution of the enolimine and ketoenamine tautomers, likely as a result of a more polar active site for O-acetylserine sulfhydrylase B and the preference for the neutral species at high pH compared to the A-isozyme.
Altered thermodynamics from remote mutations altering human toward bovine purine nucleoside phosphorylase.
- Mahmoud Ghanem, Lei Li, C. Wing, V. Schramm
- Chemistry, BiologyBiochemistry
- 19 February 2008
Thermodynamic parameters obtained from the temperature dependence studies of the chemical step establish E:R-PNP to be catalytically more efficient than the parent enzyme and reveal differences in the entropic component of catalysis.
Probing the reaction mechanism of spore photoproduct lyase (SPL) via diastereoselectively labeled dinucleotide SP TpT substrates.
- Linlin Yang, Geng-min Lin, Degang Liu, K. Dria, J. Telser, Lei Li
- Biology, ChemistryJournal of the American Chemical Society
- 14 June 2011
A modified reaction mechanism for this intriguing DNA repair enzyme is proposed, suggesting that some protein residue(s), which is capable of exchanging a proton with the aqueous buffer, is involved in the enzyme catalysis.
Amide N-glycosylation by Asm25, an N-glycosyltransferase of ansamitocins.
- Peiji Zhao, Linquan Bai, H. Floss
- Biology, ChemistryChemistry and Biology
- 25 August 2008
Mechanism of benzylsuccinate synthase probed by substrate and isotope exchange.
Using deuterium-labeled benzylsuccinate, the first direct evidence that the migrating hydrogen is transferred to a labile site on the protein during catalysis is provided, consistent with the participation of the proposed active-site cysteine residue in the mechanism of BSS.
Structural and Functional Analysis of Validoxylamine A 7′-phosphate Synthase ValL Involved in Validamycin A Biosynthesis
- Lina Zheng, Xiaoping Zhou, Houjin Zhang
- Biology, ChemistryPLoS ONE
- 27 February 2012
The structural data indicates that ValL adopts the typical fold of GT-B protein family, featuring two Rossmann-fold domains and an active site at domain junction, and the modeling of V7P in the active site of ValL suggests thatValL might have a similar SNi-like mechanism as OtsA.
Intracellular rebinding of transition-state analogues provides extended in vivo inhibition lifetimes on human purine nucleoside phosphorylase
- Sara T Gebre, S. Cameron, Lei Li, Y. Babu, V. Schramm
- Biology, ChemistryJournal of Biological Chemistry
- 9 August 2017
It is concluded that transition-state analogues with picomolar dissociation constants exhibit long lifetimes on their targets in vivo because the probability of the target enzyme recapturing inhibitor molecules is greater than diffusional loss to the extracellular space.
Unusually Large Deuterium Discrimination during Spore Photoproduct Formation
- D. Ames, Geng-min Lin, Yajun Jian, J. Cadet, Lei Li
- Biology, ChemistryJournal of Organic Chemistry
- 12 May 2014
Although commercially available deuterated reagents are generally satisfactory as mechanistic probes, the results argue that attention is still needed to the possible interference from the trace protiated impurity, especially when the reaction yield is low and large isotopic discrimination is involved.
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