Synthesis of azobenzenealkylmaleimide probes to photocontrol the enzyme activity of a bacterial histone deacetylase-like amidohydrolase

[Display omitted] •A series of new azobenzenealkylmaleimides (AMDs) was synthesized.•AMDs were conjugated to HDAH M30C in a 1:1M ratio.•The activities of AMD/enzyme bioconjugates can be controlled by photoswitching the attached azobenzene moiety.•Free AMDs show no inhibitory effect on HDAH C51S activity. A series of azobenzenealkylmaleimides (AMDs) with different spacer length was synthesized and coupled via Michael-Addition to a specific mutant of a bacterial histone deacetylase-like amidohydrolase (HDAH). Michaelis–Menten parameters (Vmax and Km) were employed to characterize the effect of both, the spacer length and the configuration (cis vs. trans) of the attached azobenzene moiety, on the HDAH enzyme activity. The photoswitch behavior of the AMD/enzyme conjugate activity was clearly influenced by the AMD spacer length. This study highlights the importance of steric rearrangement of the photoswitch with respect to the active site and describes a strategy to optimize the photocontrol of HDAH.