Ornithine is decarboxylated to form putrescine and carbon dioxide. Draw the reaction and using bond energies, predict the enthalpy change for this reaction.

Determine the structures of the molecules described in the following problems. Also note, in the combustion of N containing compounds, N₂(g)  is made.

4. Ornithine is decarboxylated to form putrescine and carbon dioxide. Draw the reaction and using bond energies, predict the enthalpy change for this reaction.

5. Ornithine decarboxylase (the enzyme that catalyzes the reaction in problem 1) is a target for ubiquitylation. In this process, ubiquitin (a small protein) is covalent linked to the target via an “isopeptide bond” between the side chain of lysine and the c-terminus carboxyl group of glycine. Water is released in this process. Predict the enthalpy change of this reaction using bond enthalpies.

6. Often we Hess’s law to determine enthalpies of reactions we are interested in using data from reactions we know. The heat of combustion of glycyl-glycine (dipeptide) is 1972 kJ/mol. The heat of combustion of glycine is -969kJ/mol. Is this enough information to determine the enthalpy of the reaction for forming the dipeptide (and associated products) from the amino acid? If it is, what is it?