Rhamnogalacturonan exolyase

Rhamnogalacturonan exolyase (EC 4.2.2.24, YesX) is an enzyme with systematic name alpha-L-rhamnopyranosyl-(1->4)-alpha-D-galactopyranosyluronate exolyase. This enzyme catalyses the following chemical reaction

Exotype eliminative cleavage of alpha-L-rhamnopyranosyl-(1->4)-alpha-D-galactopyranosyluronic acid bonds of rhamnogalacturonan I oligosacharides containing alpha-L-rhamnopyranose at the reducing end and 4-deoxy-4,5-unsaturated D-galactopyranosyluronic acid at the non-reducing end.

The enzyme is part of the degradation system for rhamnogalacturonan I in Bacillus subtilis strain 168.