Discontinuity of charge on cell wall poles of Bacillus subtilis

When cell wall poles of Bacillus subtilis were treated with dilute cationized ferritin, label was found only at discrete patches. Since cationized ferritin binds to negatively charged groups, the pole regions that retain label most likely represent localized surface sites of high electronegativity, indicating that the cell wall of B. subtilis is, at least, partially differentiated.