Two polyester polyurethane (PU)-degrading enzymes from Pseudomonas chlorora
phis, a bacterium that utilizes polyester PU as the sole carbon and energy
source, were purified to electrophoretic homogeneity as indicated by sodium
dodecyl-polyacrylamide gel electrophoresis (SDS-PAGE). Both enzymes are ex
tracellular soluble proteins with molecular weight of 63,000 Da and 31,000
Da. The 63,000 Da protein exhibits both esterase and protease activities to
ward rho-nitrophenylacetate and hide powder azure respectively. The enzyme
has an optimum pH of 8.5 for esterase activity and an optimum pH of 7.0 for
protease activity. The 31,000 Da protein exhibits esterase activity toward
rho-nitrophenylacetate, butyrate and propionate, and has an optimum pH of
8.5. In addition, the enzyme activities of both proteins are heat stable af
ter 10min at 100 degrees C and are inhibited 50% by the addition of 1 mM ph
enylmethylsulfonylfluoride indicating both are serine-hydrolases, (C) 1999
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