Mechanism and kinetics modeling of the enzymatic hydrolysis of α1-32 antibacterial peptide

Several antibacterial peptides can be obtained by enzymatic hydrolysis of the α chain of bovine hemoglobin. The kinetics of α1-32 peptide hydrolysis by pepsin was studied at several temperatures (15, 23 and 37 °C). Intermediate and final peptides were identified, and their antibacterial activity was assessed against four bacterial species. Evolution of generated peptides concentration enabled to propose a reaction pathway describing the parallel and consecutive reactions taking place during the hydrolysis. A mathematical model, based on the proposed mechanism, was developed to describe the kinetics of generated peptides during α1-32 hydrolysis. The constants of the main reactions were identified based on the experimental data, and their dependence on temperature was established using Arrhenius-type equations. Validation of the proposed model was performed by predicting kinetics of α1-32 peptide hydrolysis at 30 °C (all other experimental conditions being unchanged) with a good accuracy. This mathematical model could allow defining the optimal conditions for the production of various intermediate peptides with antibacterial activity from peptic hydrolysis of α1-32 peptide.