Nucleotides interaction strength

The differences between the two studies may be due to different solution conditions. The same stoichiometry (4 nucleotides per g5p) was used, but there were significant differences in ionic strength and pH (7.7 versus 7.0), as well as the presence or absence of EDTA. The binding of SSBP, like other protein-DNA interactions, is known to be highly sensitive to ionic strength. 

Strength of interactions Nucleotides have the potential for far stronger interactions than amino acids. An additional bp to a secondary structural helix coutributes -4.18 to -2.55kJ/mol. Isolated protein secondary structures are usually unstable in the absence of the rest of the protein. A folded protein has only a modest stability in the order of 1.84kJ/mol. 

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