Growth of Pseudomonas chlororaphis on a polyester-polyurethane and the purification and characterization of a polyurethanase esterase enzyme

A Pseudomonas chlororaphis was found to degrade and utilize a polyester polyurethane as a sole carbon and energy source. Polyurethane utilization by P. chlororaphis followed simple Michaelis-Menten kinetics. The K sub(s) and mu sub(max) values were 0.802 mg times ml super(-1) and 1.316 doublings times h super(-1), respectively. The enzymes from P. chlororaphis responsible for polyurethane degradation were found to be extracellular. Analysis of the polyurethane degrading proteins, using non-denaturing polyacrylamide gel electrophoresis, revealed three active protein bands with R sub(f) values of 0.25, 0.417 and 0.917. A polyurethane degrading enzyme was purified and displayed esterase activity. This enzyme was inhibited by phenylmethylsulfonyl fluoride and had a molecular weight of 27,000 daltons.