Pectinolytic enzymes consist of four classes of enzymes: pectin lyase, polygalacturonase, pectin methylesterase and rhamnogalacturonase. Degrades the rhamnogalacturonan I (RG-I) backbone of pectin. Active against linseed rhamnogalacturonan. Endotype eliminative cleavage of L-alpha-rhamnopyranosyl-(1->4)-alpha-D-galactopyranosyluronic acid bonds of rhamnogalacturonan I domains in ramified hairy regions of pectin leaving L-rhamnopyranose at the reducing end and 4-deoxy-4,5-unsaturated D-galactopyranosyluronic acid at the non-reducing end. Belongs to the polysaccharide lyase 4 family.