Structural Requirements for Catalysis by Chorismate Mutase

Article abstract of DOI:10.1021/ja00191a040

The structural requirements for mutase-catalyzed Claisen rearrangement by chorismate mutase-prephenate dehydrogenase from Escherichia coli have been established.The chorismate analogue lacking the carboxyl group at C1 (5) was not a substrate for chorismate mutase.The methyl ether of chorismate <(+/-)-6> was a good substrate for chorismate mutase (k_cat/k_uncat = 2.0*1E4).The half-lives for Claisen rearrangement and aromatization of 4-deshydroxychorismate (19) in D2O at 30 deg C, pD 7.2, were 3.5 and 8 min, respectively.In the presence of large amounts of enzyme,it was demonstrated that the Claisen rearrangement of enantiomerically pure 19 was accelerated at least 100-fold by chorismate mutase.Data available from other studies have demonstrated that ester 3 is not a substrate for chorismate mutase, and the k_cat/k_uncat for dihydrochorismate analogue 4 is similar to that for chorismate.These results establish that the only functional groups required on the allyl vinyl ether moiety of chorismate for mutase-catalyzed rearrangement are the two carboxylate groups.