The Ehrlich ascites carcinoma (EAC) contains 300-500 Da inhibitor(s) suppressing DNA synthesis in cultured EAC cells and EAC cell division in tumor-bearing mice.

A protein preparation obtained from the Ehrlich ascites carcinoma (EAC) by acetone precipitation, water extraction and subsequent two-step alcohol fractionation reduced significantly EAC cell proliferation in vivo and in vitro. The preparation was found to contain a low molecular-weight growth-inhibitory activity, suppressing both DNA synthesis in cultured EAC cells and EAC cell division in tumor-bearing mice. The approximate molecular weight of this inhibitory component(s) is about 300-500 Da, corresponding to oligopeptide molecule(s).

Isoelectric focusing of bacterial DNA methylases.

The multiplicity of bacterial DNA methylases has been shown for new microorganisms, Mycobacteria and Shigella, by a double-step procedure including column chromatography followed by isoelectric focusing of the total methylase fraction. The profiles of the DNA methylating activity of Sh. sonnei 47 and M.