pH Titration Studies of the Acid Denaturation of Calf Thymus Deoxyribosenucleic Acid

Year: 1961

DOI: 10.7907/MME6-8038

The acid denaturation of calf thymus deoxyribosenucleic acid (DNA) has been studied both by PH and
spectrophotometric titration in the temperature range
10 - 30°C and at ionic strengths 0.1 F and 0.5 F. The
number of hydrogen ions bound by the DNA at any given
pH increased with increasing temperature and decreased
with increasing ionic strength. The number bound at
any given pH was greater after denaturation. A model
for acid denaturation is proposed. The site of protonation of cytosine is discussed.