title: Stereospecificity, substrate, and inhibitory properties of nucleoside diphosphate analogs for creatine and pyruvate kinases.
abstract: Antiviral alpha-P-borano substituted NTPs are promising chain terminators targeting HIV reverse transcriptase (RT). Activation of antiviral nucleoside diphosphates (NDPs) to NTPs may be carried out by pyruvate kinase (PK) and creatine kinase (CK). Herein, are presented the effects of nucleobase, ribose, and alpha-phosphate substitutions on substrate specificities of CK and PK. Both enzymes showed two binding modes and negative cooperativity with respect to substrate binding. The stereospecificity and inhibition of ADP phosphorylation by alpha-P-borano substituted NDP (NDPalphaB) stereoisomers were also investigated. The Sp-ADPalphaB isomer was a 70-fold better substrate for CK than the Rp isomer, whereas PK preferred the Rp isomer of NDPalphaBs. For CK, the Sp-ADPalphaB isomer was a competitive inhibitor; for PK, the Rp-ADPalphaB isomer was a poor competitive inhibitor and the Sp-ADPalphaB isomer was a poor non-competitive inhibitor. Taken together, these data suggest that, although the Rp-NDPalphaB isomer would be minimally phosphorylated by CK or PK, it should not inhibit either enzyme.
authors.affiliation: Department of Chemistry, French Family Science Center, Duke University, 124 Science Drive, Durham, NC 27708-0354, USA.
authors.forename: Charlotta K
authors.initials: CK
authors.lastname: Wennefors
authors.forename: Mikhail I
authors.initials: MI
authors.lastname: Dobrikov
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Xu
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.forename: Barbara Ramsay
authors.initials: BR
authors.lastname: Shaw
mesh_terms: D017766:Acid Anhydride Hydrolases / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D003402:Creatine Kinase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D015226:Dinucleoside Phosphates / Q000737:chemistry* / Q000494:pharmacology*; D007700:Kinetics; D015394:Molecular Structure; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors / Q000737:chemistry* / Q000494:pharmacology*; D011770:Pyruvate Kinase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011817:Rabbits; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D000099170:Bis(5'-adenosyl)triphosphatase
chemical_list: D017766:Acid Anhydride Hydrolases; D003402:Creatine Kinase; D015226:Dinucleoside Phosphates; D047428:Protein Kinase Inhibitors; D011770:Pyruvate Kinase; D000099170:Bis(5'-adenosyl)triphosphatase