Purification and characterization of a soluble polyurethane degrading enzyme from Comamonas acidovorans

A soluble esterase involved in the biodegradation of polyester polyurethane (PU) was purified to apparent electrophoretic homogeneity in high yield, similar to 83%. The enzyme displayed a single band on both non-denaturing (ND-) and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) with an apparent molecular mass of 42 kDa. Using rho -nitrophenylacetate as the substrate, the enzyme displayed steady-state kinetic parameters K sub(m) and V sub(max) of 51.5 mM and 180 U mg super(-1) respectively. Esterase activity was thermally stable and could be inhibited with phenylmethylsulfonylfluoride (PMSF) and soybean trypsin inhibitor (STI).