Purification and Properties of a Polyester Polyurethane-Degrading Enzyme from Comamonas acidovorans TB-35

Abstract

A polyester polyurethane (PUR)-degrading enzyme, PUR esterase, derived from Comamonas acidovorans TB-35, a bacterium that utilizes polyester PUR as the sole carbon source, was purified until it showed a single band in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). This enzyme was bound to the cell surface and was extracted by addition of 0.2%N,N-bis(3-d-gluconamidopropyl)deoxycholamide (deoxy-BIGCHAP). The results of gel filtration and SDS-PAGE showed that the PUR esterase was a monomer with a molecular mass of about 62,000 Da. This enzyme, which is a kind of esterase, degraded solid polyester PUR, with diethylene glycol and adipic acid released as the degradation products. The optimum pH for this enzyme was 6.5, and the optimum temperature was 45°C. PUR degradation by the PUR esterase was strongly inhibited by the addition of 0.04% deoxy-BIGCHAP. On the other hand, deoxy-BIGCHAP did not inhibit the activity whenp-nitrophenyl acetate, a water-soluble compound, was used as a substrate. These observations indicated that this enzyme degrades PUR in a two-step reaction: hydrophobic adsorption to the PUR surface and hydrolysis of the ester bond of PUR.

Properties of a bacterium which degrades solid poly(tetramethylene succinate)-co-adipate, a biodegradable plastic

“…Our studies provide the ¢rst evidence of a high-molecular-mass PBSA-degrading bacterium inhabiting a real ecosystem and producing lipase to degrade PBSA. Furthermore, this enzyme exhibited similar characteristics to the polyester^polyurethane-degrading enzyme (PUR esterase) reported previously by us [10]. As reported by us, PUR esterase possesses a hydrophobic substrate surface-binding domain besides a catalytic domain, and PUR degradation occurs in two steps, adsorption to substrate and hydrolysis.…”

UV-Surface Treatment of Fungal Resistant Polyether Polyurethane Film-Induced Growth of Entomopathogenic Fungi

“…Pristine films showed a hydrophobic surface with a WCA of 92° (see Table S1 ), which means that it is a non-favorable surface for water-soluble enzyme molecules. In previous studies, it was shown that insoluble PU substrates can be degraded by enzyme molecules which, by an unknown process, attach themselves onto the surface of the insoluble substrates [ 43 ]. After the adhesion process, the enzymatic reaction may rapidly proceed in some cases [ 1 ].…”

Biofilm formation byExiguobacteriumsp. DR11 and DR14 alter polystyrene surface properties and initiate biodegradation

“…It is a relatively slow process in which cleavage of polymer backbone by bond scission leads to generation of carbonyl groups (oxidation) which are considered to be utilized by the microorganism as a source of carbon and energy. [11][12][13] There are a few reports showing biodegradation of synthetic polymers including polyethylene, polyurethane, polyvinyl chloride [14][15][16][17][18][19][20] and their microplastic forms. [21][22][23] PS also belongs to a non-biodegradable class of synthetic polymers 12 but very limited data is available on its biodegradation.…”