Entry M0284 188.8.131.52 thiocyanate hydrolase
Tyr108 activates a water molecule towards nucleophilic attack on the Co(III) coordinated thiocyanate substrate.
Comment: It is unknown whether the post translational hydroxylation of Cys133 results in a protonated hydroxyl or anionic hydroxide functionality .
Crystallographic data suggests Co(III) forms a pentavalent coordination environment. The distal position is seen not to coordination to water, as is the case for the related enzyme Nitrile hydrolase, but instead binds the thiocyanate substrate via its nitrogen. The metal centre acts as a Lewis acid, increasing the electrophilic character of the bound thiocyanate .
Both Tyr108 and Cys133 have been identified as hydrolysis activating residues, although their precise roles are only partially characterised .
Amino acids involved in the reaction step.
Metal Cofactors involved in Step 01
||Bonds Changed in Order
||Atom Types Involved
The C-S bond changes from a double to single bond
View similar reactions in MACiE.