How might they resolve the discrepancy | Homework Helpers

In a cell biology laboratory experiment, two students independentlyisolated the enzyme lactate dehydrogenase, which catalyzes thereduction of pyruvate to lactate, from chicken heart. The enzymewas obtained in the form of a concentrated solution. The studentsthen measured the activity of their own enzyme solution as afunction of substrate concentration under identical conditions andfrom the data determined the Vmax and KM of their own preparation.When they compared results, they noticed that their values of KMwere identical, but their values of Vmax were radically different.One student argued that the different Vmax values confirmed thatthey had isolated different forms of the same enzyme. The otherstudent argued that, in spite of different Vmax values, they hadisolated the same form of the enzyme.

(a) Which student was correct? Why? (be explicit – useequations)

(b) How might they resolve the discrepancy?