Studies on the permeability change produced in coliform bacteria by ethylenediaminetetraacetate.

摘要: Ethylenediaminetetraacetate added to washed cells in tris (hydroxymethyl) aminomethane buffer increases the surface permeability of all coliforms tested, including nine strains Escherichia coli, one strain Aerobacter aerogenes, and four species Salmonella. Although this treatment passive permeability, two transport systems tested were unaffected. The change is complete within 15 sec after EDTA addition at both 4° 37°. Mg++ metals greater affinity than for prevent change; Na+ K+ do not. Those ions that action cannot immediately reverse it. As treated metabolize, they repair their barrier, restoring it completely a period equivalent two-thirds doubling time. Tests conditions necessary permit suggest requires energy metabolism but does not require protein synthesis, RNA or mucopeptide synthesis. results support hypothesis causes by binding metal, probably Mg++, cell then undergoes steric chemical its reversal.