Biomaterial Database

Transition state stabilization by six arginines clustered in the active site of creatine kinase. 2005

Michael J Jourden, and Paul R Geiss, and Michael J Thomenius, and Lindsay A Horst, and Melissa M Barty, and Melissa J Brym, and Guy B Mulligan, and Ryan M Almeida, and Betsy A Kersteen, and Nichole R Myers, and Mark J Snider, and Charles L Borders, and Paul L Edmiston

Department of Chemistry, College of Wooster, Wooster, OH 44691, USA.

Six fully conserved arginine residues (R129, R131, R235, R291, R319, and R340) closely grouped in the nucleotide binding site of rabbit muscle creatine kinase (rmCK) were mutated; four to alanine and all six to lysine. Kinetic analyses in the direction of phosphocreatine formation showed that all four alanine mutants led to substantial losses of activity with three (R129A, R131A, and R235A) having no detectable activity. All six lysine mutants retained variable degrees of reduced enzymatic activity. Static quenching of intrinsic tryptophan fluorescence was used to measure the binding constants for MgADP and MgATP. Nucleotide binding was at most only modestly affected by mutation of the arginine residues. Thus, the cluster of arginines seem to be primarily responsible for transition state stabilization which is further supported by the observation that none of the inactive mutants demonstrated the ability to form a transition analogue complex of MgADP.nitrate.creatine as determined by fluorescence quenching assays. As a whole, the results suggest that the most important role these residues play is to properly align the substrates for stabilization of the phosphoryl transfer reaction.

UI	MeSH Term	Description	Entries
D007527	Isoenzymes	Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.	Alloenzyme,Allozyme,Isoenzyme,Isozyme,Isozymes,Alloenzymes,Allozymes
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008239	Lysine	An essential amino acid. It is often added to animal feed.	Enisyl,L-Lysine,Lysine Acetate,Lysine Hydrochloride,Acetate, Lysine,L Lysine
D008958	Models, Molecular	Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.	Molecular Models,Model, Molecular,Molecular Model
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D010725	Phosphocreatine	An endogenous substance found mainly in skeletal muscle of vertebrates. It has been tried in the treatment of cardiac disorders and has been added to cardioplegic solutions. (Reynolds JEF(Ed): Martindale: The Extra Pharmacopoeia (electronic version). Micromedex, Inc, Englewood, CO, 1996)	Creatine Phosphate,Neoton,Phosphocreatine, Disodium Salt,Phosphorylcreatine,Disodium Salt Phosphocreatine,Phosphate, Creatine
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D011817	Rabbits	A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes.	Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
D003401	Creatine	An amino acid that occurs in vertebrate tissues and in urine. In muscle tissue, creatine generally occurs as phosphocreatine. Creatine is excreted as CREATININE in the urine.
D003402	Creatine Kinase	A transferase that catalyzes formation of PHOSPHOCREATINE from ATP + CREATINE. The reaction stores ATP energy as phosphocreatine. Three cytoplasmic ISOENZYMES have been identified in human tissues: the MM type from SKELETAL MUSCLE, the MB type from myocardial tissue and the BB type from nervous tissue as well as a mitochondrial isoenzyme. Macro-creatine kinase refers to creatine kinase complexed with other serum proteins.	Creatine Phosphokinase,ADP Phosphocreatine Phosphotransferase,ATP Creatine Phosphotransferase,Macro-Creatine Kinase,Creatine Phosphotransferase, ATP,Kinase, Creatine,Macro Creatine Kinase,Phosphocreatine Phosphotransferase, ADP,Phosphokinase, Creatine,Phosphotransferase, ADP Phosphocreatine,Phosphotransferase, ATP Creatine