The inhibitor of κB kinase β (IKKβ) phosphorylates IκBα twice in a single binding event through a sequential mechanism
AA Stephenson, DJ Taggart, G Xu, JD Fowler… - Journal of Biological …, 2023 - ASBMB
Phosphorylation of Inhibitor of κB (IκB) proteins by IκB Kinase β (IKKβ) leads to IκB
degradation and subsequent activation of nuclear factor κB transcription factors. Of particular
interest is the IKKβ-catalyzed phosphorylation of IκBα residues Ser 32 and Ser 36 within a
conserved destruction box motif. To investigate the catalytic mechanism of IKKβ, we
performed pre–steady-state kinetic analysis of the phosphorylation of IκBα protein substrates
catalyzed by constitutively active, human IKKβ. Phosphorylation of full-length IκBα catalyzed …
degradation and subsequent activation of nuclear factor κB transcription factors. Of particular
interest is the IKKβ-catalyzed phosphorylation of IκBα residues Ser 32 and Ser 36 within a
conserved destruction box motif. To investigate the catalytic mechanism of IKKβ, we
performed pre–steady-state kinetic analysis of the phosphorylation of IκBα protein substrates
catalyzed by constitutively active, human IKKβ. Phosphorylation of full-length IκBα catalyzed …