You are trying to determine whether it is better to purify an enzyme from its natural source or to express the gene in bacteria and then purify it. You purify it from both sources and show that each preparation gives a single band by denaturing gel electrophoresis, a common measure of purity. When you compare the kinetic parameters, you find that both enzymes have the same Km but the enzyme from the bacteria has a 10-fold lower Vmax. Propose possible explanations for this result.