To begin to answer that question you need to put the DNA into the proper perspective. The DNA is like the hard drive of the cell. It has all the data. However, it is not CPU or the central processing unit. The DNA needs a processor to make use of that data. During cells cycles the DNA is duplicated and then pack into chromosomes. While the DNA is taken offline, the protein grid is still working. The protein gird of live cells appears to be the processor. You cannot put DNA in water, along with small organic chemicals, and expect to make a cell. It is just the hard drive. When two daughter cells form, each has all the material for another protein gird, allow the duplicated DNA hard drive, to also have a duplicate processor. In multicellular differentiation, all cells have the same DNA, but each has a different protein gird processor derived from parts of the DNA
In an active cell, The DNA hard drive, with the help of the protein grid processor, supplies mRNA, which then become templates for raw protein. In this raw state, the proteins are not bioactive. It is the water that folds and packs the protein into their bioactive shapes. If you were to change the solvent, the raw protein would not fold/pack or be processed by that solvent, the same way and no life or bioactivity would appear. Water at the most base level is the CPU, since it folds, packs and combines all the biomaterials needed for both the hard drive and the processor.
Although not commonly presented in textbooks, DNA has a double helix of water intertwined in the major and minor grooves of the double helix. The base pairs have more hydrogen bonding sites earmarked for water, than for the bases pairs. DNA without that water does not work. It is an extra water processing step the DNA needs.
The living state is all about secondary bonding forces. These are weaker bonds that can break and reform. The primary bonds are stronger and stay steady. While all the activities of life happen at the more pliable secondary bonding level. Water forms hydrogen bonds, with each water molecule able to form up to four hydrogen bonds. This, the small size of water molecules, and their abundance in life, makes water the king of secondary bonds. This is how water can pack and fold protein; water rules the secondary bonding roost.
The fluid water matrix needs to stay optimized to itself, and to do so it will reconfigure the secondary bonding of the protein, so they form a shape more favorable to the water. This optimize shape lowers the protein entropy; less complex, and it becomes bioactive. The entire protein grid is optimized to the water, which makes water the base CPU, which through the muscle of the protein gird middlemen, processes the DNA hard drive.
Water is like a stable bookend, in that water formed from a very energetic reaction between oxygen and hydrogen. Water is stable and has not change from H2O, since ever. The organic material are more opposite in that there is endless variety. The stable bookend of the H2O processor has been around since before life, and through the same hydrogen bonding matrix of old, it still processes new organics the same way. The goal of water is also the goal of evolution. Variety of organics does not matter to water. The king water has spoken.
As life evolves and more and more organic collect the water is being pushed against, which sort of impacts the water matrix. But this never change sits status as the king of secondary bonding. It simply shifts the set point with each step upward.
One of the most critical changes in evolution was ion pumping and exchange. That single chance increased the speed of evolution. The reason is these two main cations, sodium and potassium, each have the opposite impact on the hydrogen bonding matrix of water. Sodium is kosmotropic while potassium is chaotropic. Sodium creates more order in water while potassium creates more disorder in water. Cells tend to accumulate potassium which by increasing the disorder of water, increases the entropy of the aqueous matrix; greater pushes toward more complexity. The sodium on the outside makes that water matrix behave different. It makes more order, which makes it easier to lock and key material to the transport proteins. Water and potassium have a lot to do with new writing to the DNA, via the protein grid.
One last interesting observation is if cell membrane are removed from cells, so there are no ion pumping. potassium ions will still preferentially accumulate inside the naked cell. This tells me, the ion pumping created an equilibrium Water-Potassium-protein balance that reflected the chaotropic nature of potassium in water. The processor evolved all together as a type of compensatory balance.