Reply To Roglin Et Al.: Synchrotron Radiation-Induced Covalent Modification Of 14-3-3 Zeta By Diazene Compounds Containing Pyridoxal Phosphate

In the letter by Röglin et al. (1), the authors show that pyridoxal phosphate (PLP) derivatives form reversible covalent imine adducts with lysine(s) of 14-3-3σ through coupling between the N6-amine group of lysine and the aldehyde group of the compound. Their X-ray diffraction experiments are performed by using Cu-Kα radiation with a wavelength of 1.5418 Å and the crystals obtained under crystallization conditions with pH 7.4. In our original study (2), we discussed the imine adduct model for 14-3-3ζ protein interactions with FOBISIN101, a small molecule containing an -N=N- diazene bond that links the pyridoxal phosphate and benzoate moieties. However, under our experimental conditions (pH 8.5 and synchrotron …