Reaction mechanisms of thiamin diphosphate enzymes: defining states of ionization and tautomerization of the cofactor at individual steps

TitleReaction mechanisms of thiamin diphosphate enzymes: defining states of ionization and tautomerization of the cofactor at individual steps
Publication TypeJournal Article
Year of Publication2009
AuthorsNemeria, NS, Chakraborty S, Balakrishnan A, Jordan F
JournalFebs Journal
Volume276
Pagination2432-2446
Date PublishedMay
ISBN Number1742-464X
Accession Numberhttp://apps.isiknowledge.com/InboundService.do?Func=Frame&product=WOS&action=retrieve&SrcApp=EndNote&Init=Yes&SrcAuth=ResearchSoft&mode=FullRecord&UT=000264882700002
Abstract

We summarize the currently available information regarding the state of ionization and tautomerization of the 4'-aminopyrimidine ring of the thiamine diphosphate on enzymes requiring this coenzyme. This coenzyme forms a series of covalent intermediates with its substrates as an electrophilic catalyst, and the coenzyme itself also carries out intramolecular proton transfers, which is virtually unprecedented in coenzyme chemistry. An understanding of the state of ionization and tautomerization of the 4'-aminopyrimidine ring in each of these intermediates provides important details about proton movements during catalysis. CD spectroscopy, both steady-state and time-resolved, has proved crucial for obtaining this information because no other experimental method has provided such atomic detail so far.

URLhttp://apps.isiknowledge.com/InboundService.do?Func=Frame&product=WOS&action=retrieve&SrcApp=EndNote&Init=Yes&SrcAuth=ResearchSoft&mode=FullRecord&UT=000264882700002