Ultrastructural changes in rhizobium leguminosarum due to exposure to the antimicrobial agent Irgasan
Cobb, Douglas B.
MetadataShow full item record
Rhizobium leguminosarum, a gram-negative nitrogenfixing organism that is commonly associated with plants of the pea group,was found to be susceptible to 1-2ppm of irgasan. It was also found that while strains of E. coli required the addition of divalent cations such as Mg or Ca to become resistant to irgasan and other halogenated bisphenols, the resistant strains of R. leguminosarum that were tested did not require the addition of these ions. The electron microscope did,however, reveal changes in the ultrastructure of organisms subjected to irgasan stress, lending credence to the view that the cell envelope of gra.m-negative organisms acts as an "adsorbing barrier," screening out many substances which may be toxic to the cell.