title: α-Carbonic anhydrases are sulfatases with cyclic diol monosulfate esters.
abstract: Carbonic anhydrases (CA) catalyze activated ester hydrolysis in addition to the hydration of CO(2) to bicarbonate. They also show phosphatase activity with 4-nitrophenyl phosphate as substrate but not sulfatase with the corresponding sulfate. Here we prove that the enzyme is catalyzing the synthesis of cyclic diols from sulfate esters. 5-, 6- and 8-membered ring cyclic sulfates incorporating a neighboring secondary alcohol moiety were treated with CA II and yielded the corresponding cyclic diols. Inhibitory properties of obtained cyclic and original sulfate esters were then investigated on human carbonic anhydrase I (hCA I), hCA II, hCA IV and hCA VI (h = human isoform). K(I)-s of these compounds ranged between 32.7-423 μM against hCA I, 2.13-32.4 μM against hCA II, 13.7-234 μM against hCA IV and 76-278 μM against CA VI, respectively. The sulfatase activity of CA with such esters is amazing considering the fact that 4-nitrophenyl-sulfate is not a substrate of these enzymes.
authors: Department of Elementary Education, Dumlupınar University, Kütahya, Turkey.
authors: Hüseyin
authors: H
authors: Cavdar
authors: Deniz
authors: D
authors: Ekinci
authors: Oktay
authors: O
authors: Talaz
authors: Nurullah
authors: N
authors: Saraçoğlu
authors: Murat
authors: M
authors: Sentürk
authors: Claudiu T
authors: CT
authors: Supuran
mesh_terms: D000438:Alcohols / Q000737:chemistry / Q000378:metabolism*; D055162:Biocatalysis; D002256:Carbonic Anhydrases / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D004952:Esters / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D006801:Humans; D006868:Hydrolysis; D013329:Structure-Activity Relationship
chemical_list: D000438:Alcohols; D004791:Enzyme Inhibitors; D004952:Esters; D002256:Carbonic Anhydrases