Critical analysis of peptidoglycan structure of Lactobacillus acidophilus for phthalate removal

Our previous studies have shown that lactic acid bacteria (LABs) can bind and remove di-n-butyl phthalate (DBP), diethyl phthalate, dioctyl phthalate; three ubiquitous environmental contaminants. In this study, Lactobacillus acidophilus NCFM was chosen to study the DBP binding mechanism. We found three-dimensional structure of bacterial cell wall, including carbohydrates proteins, essential for adsorption. Peptidoglycan main component in wall (80.71%), sites exposed were C–N, N–H, O–H, C–O bonds. Molecular dynamic (MD) demonstrated hydrophobic interaction plays an important role adsorption, chemical influenced peptidoglycan model O2, O3>N1, N2, N3>O1, O4, form adsorption force included hydrogen bonding force, electrostatic van der Waals forces. These theoretical data from MD simulation consistent with experimental results terms ability bacterium DBP, so proposed a new way investigate mechanisms LABs.