Preliminary study of the mechanism of gentamicin bound by peptidoglycan of the cell wall of Micromonospora echinospore var.

Cell wall (CW) and peptidoglycan (PG) were isolated from Micromonospora echinospora. PG, the major part of cell wall, can bind about 95 % of the total GM adsorbed on the cell wall. The optimum pH appeared to be 4-9 for the binding of GM by peptidoglycan. The maximum content of bound GM was ca. 88000u/g of dry weight of peptidoglycan and no any free GM was detected in the solution. Metal ions and amine compete with GM for the binding site. Mg²⁺ and Na⁺ desorbed the binding of GM intensively at GM concentration less than 1000u/ml and more than 2000u/ml, respectively. Tris can also release GM from peptidoglycan to a certain degree.