SAR analysis of adenosine diphosphate (hydroxymethyl)pyrrolidinediol inhibition of poly(ADP-ribose) glycohydrolase.
Polyadenosine diphosphoribose glycohydrolase (PARG) catalyzes the intracellular hydrolysis of adenosine diphosphoribose polymers. Because structure-activity data are lacking for PARG, the specific inhibitor adenosine diphosphate (hydroxymethyl)pyrrolidinediol (ADP-HPD) was utilized to determine the effects of structure on inhibitor potency using PARG isolated from bovine thymus (bPARG) and recombinant bovine PARG catalytic fragment (rPARG-CF). Both enzymes were strongly inhibited by submicromolar levels of ADP-HPD, but ADP and the phosphorylated pyrrolidine displayed no activity. Utilizing ADP-HPD analogues containing 2-, N(6), or 8-adenosyl substituents or guanine instead of adenine, the importance of adenine ring recognition as well as a correlation between loss of PARG inhibition and the length and bulkiness of 8-adenosyl substituents was shown. Utilization of ADP-HPD analogues lacking one or both pyrrolidine cis-hydroxyls demonstrated their importance for inhibitor binding. Last, the similarity between naturally occurring bPARG and heterologously expressed rPARG-CF was demonstrated. Therefore, readily available rPARG-CF is suitable for use in future studies to determine the structural aspects of PARG.
D000244:Adenosine Diphosphate / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D000818:Animals; D001665:Binding Sites; D002417:Cattle; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D006026:Glycoside Hydrolases / Q000037:antagonists & inhibitors* / Q000235:genetics; D020128:Inhibitory Concentration 50; D010446:Peptide Fragments / Q000037:antagonists & inhibitors / Q000235:genetics; D011064:Poly Adenosine Diphosphate Ribose / Q000378:metabolism; D011759:Pyrrolidines / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D011994:Recombinant Proteins / Q000037:antagonists & inhibitors / Q000235:genetics; D013329:Structure-Activity Relationship
D004791:Enzyme Inhibitors; D010446:Peptide Fragments; D011759:Pyrrolidines; D011994:Recombinant Proteins; C096272:adenosine diphosphate (hydroxymethyl)pyrrolidinediol; D011064:Poly Adenosine Diphosphate Ribose; D000244:Adenosine Diphosphate; D006026:Glycoside Hydrolases; C022407:poly ADP-ribose glycohydrolase