Simple methanesulfonates are hydrolyzed by the sulfatase carbonic anhydrase activity

The possible sulfatase activity of several carbonic anhydrase (CA, EC 4.2.1.1) isoforms have been investigated with a series of synthesized methanesulfonate derivatives of phenols. Four alpha-CA isozymes, i.e. hCA I, hCA II, hCA IV and hCA VI (h = human isoform), were included in the study. We evidenced that the original sulfonate esters are being hydrolyzed effectively to the corresponding phenols which there after act as CA inhibitors. The K-I-s of these compounds ranged from 10.24 to 4012 mu M against hCA I, 0.10 to 35.42 mu M against hCA II, 0.49 to 45.06 mu M against hCA IV and 3.27 to 608 mu M against CA VI, respectively. The relevant sulfatase activity of CA with these esters is amazing considering the fact that 4-nitrophenyl-sulfate, an activated ester, is not a substrate of these enzymes.