Polymeric enzyme mimics: catalytic activity of ribose-containing polymers for a phosphate substrate.
The polymers containing ribose rings: poly(5'-acrylamido-5'-deoxy-1',2'-O-isopropylidene-alpha-D-ribose) (11), poly(5'-acrylamido-5'-deoxy-alpha-D-ribose) (12) and poly(5'-acrylamido-5'-deoxy-1'-O-methyl-D-ribose) (13) were prepared as enzyme mimics. Polymers 12 and 13 with free vic-cis-diol groups catalyzed the hydrolysis of phosphodiester (ethyl p-nitrophenyl phosphate and N-methylpyridinium 4-tert-butylcatechol cyclic phosphate) and phosphomonoester substrates with a rate acceleration of 10 approximately equal to 10(3) compared with the uncatalyzed reaction. They also catalyzed the reverse reactions, i.e., the esterification of phosphomonoester to phosphodiester and the phosphorylation of alcohols with phosphate ions. The catalytic activity was attributable to the vic-cis-diols of riboses on polymer chains, which formed hydrogen bonds with two phosphoryl oxygen atoms of phosphates so as to activate the phosphorus atoms to be attacked by nucleophiles. The catalytic activity was negligible for polymer 11 where vic-cis-diol groups were blocked with isopropylidene groups. The catalytic activity was attributable to the vic-cis-diols of riboses on polymer chains, which formed hydrogen bonds with two phosphoryl oxygen atoms of phosphates so as to activate the phosphorus atoms to be attacked by nucleophiles.
Han
Man Jung
MJ
Department of Molecular Science and Technology, Ajou University, Suwon 442-749, Korea. mjhan@ajou.ac.kr
Yoo
Kyung Soo
KS
Kim
Young Heui
YH
Chang
Ji Young
JY
D002384:Catalysis / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006868:Hydrolysis / Q000187:drug effects; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D015394:Molecular Structure; D010755:Organophosphates / Q000737:chemistry / Q000378:metabolism*; D009943:Organophosphorus Compounds / Q000737:chemistry / Q000378:metabolism; D010710:Phosphates / Q000494:pharmacology; D010766:Phosphorylation / Q000187:drug effects; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism*; D017680:Potassium Compounds / Q000494:pharmacology; D012266:Ribose / Q000138:chemical synthesis / Q000737:chemistry*; D019346:Sodium Acetate / Q000494:pharmacology; D013379:Substrate Specificity; D013997:Time Factors
D004791:Enzyme Inhibitors; D010755:Organophosphates; D009943:Organophosphorus Compounds; D010710:Phosphates; D011108:Polymers; D017680:Potassium Compounds; C042896:ethyl 4-nitrophenyl methylphosphonate; D019346:Sodium Acetate; D012266:Ribose; C013216:potassium phosphate