And proline raysimase basically catalyzes the transformation, the isomerization reaction of Lproline into Dproline. Now, the difference between Lproline and Dproline lies in the stereochemistry of this carbon. On this particular molecule, the H atom points into the board. But in this particular case, the H atom is coming out of the board. And so that's the difference between Lproline and Dproline. And proline raysimase basically catalyzes the transformation of these two molecules back and forth.