Pectinolytic enzyme that degrades type I rhamnogalacturonan from plant cell walls and releases oligosaccharide products (PubMed:16682770, PubMed:17449691, PubMed:19193638). Degrades rhamnogalacturonan, polygalacturonic acid, pectic acid and pectin (PubMed:16682770, PubMed:17449691). 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. Binds 10 calcium ions (PubMed:16682770, PubMed:17449691, PubMed:19193638). The calcium may have a structural role. Requires calcium or manganese for activity (PubMed:16682770, PubMed:17449691). Optimum pH is 8. Optimum temperature is 60 degrees Celsius. Monomer. Up-regulated by growth on type I rhamnogalacturonan. Rhamnose is bound near the active site, but there are also additional rhamnose-binding sites far away from the active site, which possibly function as a carbohydrate-binding region. Belongs to the polysaccharide lyase 11 family.