Warning: Undefined variable $zfal in C:\Inetpub\vhosts\kidney.de\httpdocs\mlpefetch.php on line 525
Deprecated: str_replace(): Passing null to parameter #3 ($subject) of type array|string is deprecated in C:\Inetpub\vhosts\kidney.de\httpdocs\mlpefetch.php on line 525

Warning: Undefined variable $sterm in C:\Inetpub\vhosts\kidney.de\httpdocs\mlpefetch.php on line 530
free
Warning: Undefined variable $sterm in C:\Inetpub\vhosts\kidney.de\httpdocs\mlpefetch.php on line 531
free
free
  English Wikipedia
Nephropedia Template TP (
Twit Text
DeepDyve Pubget Overpricing |   
lüll Reaction mechanisms of thiamin diphosphate enzymes: defining states of ionization and tautomerization of the cofactor at individual steps Nemeria NS; Chakraborty S; Balakrishnan A; Jordan FFEBS J 2009[May]; 276 (9): 2432-46We 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.|Aminopyridines/chemistry/metabolism[MESH]|Catalysis[MESH]|Circular Dichroism[MESH]|Coenzymes/chemistry/metabolism[MESH]|Kinetics[MESH]|Models, Molecular[MESH]|Structure-Activity Relationship[MESH]|Substrate Specificity[MESH]|Thiamine Pyrophosphate/*chemistry/metabolism[MESH] |