40 research outputs found

    A Complex of Methylthioadenosine/<i>S</i>-Adenosylhomocysteine Nucleosidase, Transition State Analogue, and Nucleophilic Water Identified by Mass Spectrometry

    No full text
    An enzyme-stabilized nucleophilic water molecule has been implicated at the transition state of Escherichia coli methylthioadenosine nucleosidase (<i>Ec</i>MTAN) by transition state analysis and crystallography. We analyzed the <i>Ec</i>MTAN mass in complex with a femtomolar transition state analogue to determine whether the inhibitor and nucleophilic water could be detected in the gas phase. <i>Ec</i>MTAN–inhibitor and <i>Ec</i>MTAN–inhibitor–nucleophilic water complexes were identified by high-resolution mass spectrometry under nondenaturing conditions. The enzyme–inhibitor–water complex is sufficiently stable to exist in the gas phase
    corecore