Author(s): Zare H, Moosavi-Movahedi AA, Salami M, Sheibani N, Khajeh K, Habibi-Rezaei M. Autolysis control and structural changes of purified ficin from Iranian fig latex with synthetic inhibitors. Int J Biol Macromol. 2016 Mar;84:464-71. doi: 10.1016/j.ijbiomac.2015.12.009. Epub 2015 Dec 21. PMID 26718871
Journal: International Journal Of Biological Macromolecules, Volume 84, Mar 2016
The fig’s ficin is a cysteine endoproteolytic enzyme, which plays fundamental roles in many plant physiological processes, and has many applications in different industries such as pharmaceutical and food. In this work, we report the inhibition and activation of autolysis and structural changes associated with reaction of ficin with iodoacetamide and tetrathionate using high-performance liquid chromatography (HPLC), ultra filtration membrane, and dynamic light scattering (DLS) methods. The ficin structural changes were also determined using UV-absorption, circular dichroism (CD), fluorescence spectroscopy, and differential scanning calorimetry (DSC) techniques. These techniques demonstrated that iodoacetamide completely inhibited ficin autolysis, which was irreversible. However, tetrathionate partially and reversibility inhibited its autolysis. The ficin structural changes with two synthetic inhibitors were associated with secondary structural changes related to decreased alpha-helix and increased beta sheet and random coil conformations, contributing to its aggregation.