Broad-specificity glycosaminoglycan lyase, which acts in an exolytic fashion degrading chondroitin sulfates and dermatan sulfate to yield only disaccharide products. Has a preference for chondroitin 4-sulfate over chondroitin 6-sulfate. Has extremely low activity against hyaluronic acid. Is not active against acharan sulfate, heparin or heparan sulfate. Exolytic removal of Delta(4)-unsaturated disaccharide residues from the non-reducing ends of both polymeric chondroitin/dermatan sulfates and their oligosaccharide fragments. Divalent metal cation. Requires divalent metal cation for binding of dermatan sulfate substrate, whereas it is not necessary for the binding of chondroitin sulfate substrates. Prefers Ca(2+) or Mg(2+), binding 1 ion per subunit. Specific activity for chondroitin sulfate substrates increases moderately (2-fold) while an increase of 25-fold is observed for dermatan sulfate as substrate upon addition of Ca(2+) or Mg(2+) ions (PubMed:18227125). Increasing the concentration of Na(+), K(+) or Cs(+) chloride from 0 to 0.1 M, increases the activity against all substrates. Further increases in salt concentration reduces the activity dramatically, with 50% inhibition occurring at 0.15 M and nearly complete inhibition at 0.4 M salt. The addition of 10 mM Ca(2+) or Mg(2+) ions increases the activity against chondroitin 4- and 6-sulfates by 2-3-fold, while the activity against dermatan sulfate increases much more significantly by 50-fold (PubMed:18512954). Addition of Mn(2+) and Zn(2+) reduces activity against chondroitin sulfate substrates, but increases the activity against dermatan sulfate. Increasing the concentration of CaCl(2) with both chondroitin 4- and 6-sulfates from 0 to 0.04 M increases the activity. A further increase reduces activity, with 50% inhibition at 0.065-0.085 M and a complete inhibition of the reaction at 0.2 M. In case of dermatan sulfate, the addition of low concentration of CaCl(2) dramatically increases the activity from the basal level. The maximal activity is reached at 0.01 M CaCl(2). kcat is 15792 min(-1) with chondroitin 4-sulfate from porcine or bovine trachea as substrate. kcat is 10404 min(-1) with chondroitin 6-sulfate from shark cartilage as substrate. kcat is 2307 min(-1) with dermatan sulfate from porcine intestinal mucosa as substrate. Optimum pH is 7.6. Decreased activity at pH values below 7.0 and above 8.0. The activity against chondroitin 6-sulfate remains higher than with other substrates at low pH. At pH 6.5 the enzyme exhibits almost 60% of its maximal activity against chondroitin 6-sulfate, only 20% activity against chondroitin 4-sulfate and no measurable activity against dermatan sulfate. In contrast, at pH of 8.5 about 30% of enzyme's maximal activity against all substrates is displayed. Optimum temperature is 37 degrees Celsius. No significant reduction in activity at temperatures in the range of 25-40 degrees Celsius. At 50 degrees Celsius, activity of 45% for dermatan sulfate, 60% for chondroitin 4-sulfate and 75% for chondroitin 6-sulfate is detected. Thermal denaturation curve is bimodal with two consecutive thermal denaturation midpoints (Tm) corresponding to 44 and 50 degrees Celsius, respectively. Monomer. Belongs to the polysaccharide lyase 8 family. Cloning artifact.