Properties of cold-adapted subtilisine-like proteinase of endemic yeast Leucosporidium antarcticum.

An extracellular serine proteinase from psychrophilic marine Antarctic yeast L. antarcticum has been purified to homogeneity and characterized. The enzyme specificity, which resembles both chymotrypsin and subtilisin, as well as kinetic (topt of 25 degrees C, activity up to -20 degrees C, pHoptBzTyrOEt of 8.0-8.5), and thermodynamic properties conferring cold-adaptation of the proteinase, were determined The comparison of N-terminal sequence of 35 amino acid residues with known sequences of serine proteinases indicates that the enzyme can be preliminarly classified as a subtilisin-like proteinase, belonging to the proteinase K subfamily (clan SB, family S8, subfamily C).