The Absence of Histone in the Bacterium Escherichia coli : II. X-ray Diffraction of Nucleoprotein Extract

X-ray diffraction photographs of a nucleoprotein preparation from Escherichia coli show the A-type pattern of crystalline deoxyribonucleic acid (DNA). This suggests that a large part of the DNA is free from protein. In higher organisms DNA does not exist in this form but is closely bound to protein.