The quantitative protein composition of calf thymus chromatin

The proteins of calf thymus chromatin were analysed quantitatively using a combination of polyacrylamide and cellogel electrophoreses. Quantification was achieved by determining the staining values of each purified histone with amido-black. The results indicate that, on average, 700 molecules histone F1, 850 of F2al, 1440 of F2a2, 1 890 of F2b, 2380 of F3 and 500-1000 non-histone molecules are bound per 10(5) base pairs of DNA. This suggests a moderately dense protein covering of the DNA.