Mung bean nuclease: mode of action and specificity vs synthetic esters of 3'-nucleotides.
Mung bean nuclease hydrolyzes synthetic esters of 3'-nucleotides to nucleosides and phosphate esters; esters of 2'-nucleotides, and 2'--> 5' internucleotide linkages, are resistant. Esters of ribonucleotides are cleaved at 100-fold the rate for deoxyribonucleotides, the increased rate being due to presence of the 2'-hydroxyl and not to differences in conformation. Introduction of a 5'-substituent leads to a 3-fold increase in rate. The rates of hydrolysis vary up to 10-fold with the nature of the base, in the order adenine > hypoxanthine > uracil; and up to 6-fold with the nature of the ester radical. This form of cleavage of esters of 3'-nucleotides is also characteristic for nuclease-3'-nucleotidase activities from potato tubers and wheat, suggesting that one type of enzyme is responsible for all these activities.
Kole
R
R
Sierakowska
H
H
Szemplińska
H
H
Shugar
D
D
D004951:Esterification; D006868:Hydrolysis; D007700:Kinetics; D009711:Nucleotides / Q000737:chemistry / Q000378:metabolism*; D015719:Single-Strand Specific DNA and RNA Endonucleases / Q000378:metabolism*; D013379:Substrate Specificity
D009711:Nucleotides; D015719:Single-Strand Specific DNA and RNA Endonucleases