Degrades hyaluronic acid into unsaturated disaccharides as the end products (PubMed:33561520). Exhibits very low activity against various types of chondroitin sulfate variants (PubMed:33561520). [hyaluronan](n) = n 3-(4-deoxy-beta-D-gluc-4-enuronosyl)-N-acetyl-D-glucosamine + H2O Is salt-dependent and is active over a wide range of NaCl concentrations. Activity is slightly promoted by Ni(2+), and inhibited by most of the tested metal ions, including Li(+), K(+), Ba(2+), Mg(2+), Zn(2+), Ca(2+), Mn(2+) and Al(3+). Optimum pH is 6.6. Activity is completely abolished above pH 8.6. Optimum temperature is 70 degrees Celsius. Is very stable at temperatures from 0 to 60 degrees Celsius. Predicted to be exported by the Tat system. The position of the signal peptide cleavage has not been experimentally proven. Due to its high optimal temperature and stability under a broad pH range and high temperature, TcHly8B could serve as a promising tool for the industrial production of hyaluronate oligosaccharides and promote the further exploitation of hyaluronate lyases with novel properties. Belongs to the polysaccharide lyase 8 family.