ANALYSIS OF SISOMICIN BINDING-SITES IN MICROMONOSPORA-INYOENSIS CELL-WALL

Sisomicin binding sites are located in the cell wall. They are the car boxyl groups of peptidoglycans, which are major components of the cell wall. The carboxyl groups have negative charges which can bind the po sitively charged amino groups of sisomicin. When the negative charges of the carboxyl groups of the peptidoglycans are changed to neutral or positive charges, sisomicin does not bind to the cell wall. Magnesium ions bind to the cell wall in competition with sisomicin, and have a weak affinity for the cell wall binding sites compared with sisomicin. The binding molar ratio of sisomicin to magnesium ions was approximat ely 1 to 10. (C) 1998 Federation of European Microbiological Societies . Published by Elsevier Science B.V. All rights reserved.