Which byproduct is released when a phosphodiester bond forms?

Which byproduct is released when a phosphodiester bond forms?

• A. Oxygen
• B. Water
• C. Ammonia
• D. Methane

Answer: (B)

Forming a phosphodiester bond is a dehydration synthesis, meaning a water molecule is released as the backbone is built. When a nucleotide is added to a growing strand, the 3' hydroxyl of the sugar reacts with the phosphate of the incoming nucleotide. The OH from the sugar and an H from the phosphate are removed to form water, linking the sugars with the phosphate to create the phosphodiester bond. In enzymatic terms, the reaction also releases pyrophosphate, which is quickly hydrolyzed, but the byproduct most directly tied to the bond formation in this context is water.

Forming a phosphodiester bond is a dehydration synthesis, meaning a water molecule is released as the backbone is built. When a nucleotide is added to a growing strand, the 3' hydroxyl of the sugar reacts with the phosphate of the incoming nucleotide. The OH from the sugar and an H from the phosphate are removed to form water, linking the sugars with the phosphate to create the phosphodiester bond. In enzymatic terms, the reaction also releases pyrophosphate, which is quickly hydrolyzed, but the byproduct most directly tied to the bond formation in this context is water.