You look at two papers studying the same RNAProtein binding

You look at two papers studying the same RNA-Protein binding interaction. The first was done in Tris buffer pH 8.0 with 100 mM NaCl added. The second paper reports binding data for Tris buffer, pH 8.0 with 300 mM NaCl added. The Kd for the interaction is different. In which paper would you expect to see tighter binding (a lower Kd value)? Why?

PLEASE EXPLAIN!

Solution

The binding between RNA and protein will depend on the ionic interactions and the electrostatic attraction present between the two. Sometimes the proteins are enzymes and they cannot function when the active site is not able to interact with the ions and aquire a negative or positive charge that is needed for the interaction.

since the salt has ions more salt concentration will lead to increased ionic interactions and electrostatic attractions therefore, the tighter binding would be observed in the paper that has tris buffer, pH 8.0 with 300 mM Na Cl added.