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Enzymatic surface hydrolysis of poly(ethylene terephthalate) and bis(benzoyloxy...
Eberl, A.; Heumann, Sonja; Brückner, T.; Araújo, Rita; Paulo, Artur Cavaco; Kaufmann, F.; Kroutil, W.; Gübitz, Georg M.A lipase from Thermomyces lanuginosus and cutinases from Thermobifida fusca and Fusarium solani hydrolysed poly(ethylene terephthalate) (PET) fabrics and films and bis(benzoyloxyethyl) terephthalate (3PET) endo-wise as shown by MALDI-Tof-MS, LC–UVD/MS, cationic dyeing and XPS analysis. Due to interfacial activation of the lipase in the presence of Triton X-100, a seven-fold increase of hydrolysis products relea...
A novel aryl acylamidase from Nocardia farcinica hydrolyses polyamide
Heumann, Sonja; Eberl, A.; Fischer-Colbrie, Gudrun; Pobeheim, Herbert; Kaufmann, F.; Ribitsch, D.; Paulo, Artur Cavaco; Gübitz, Georg M.An alkali stable polyamidase was isolated from a new strain of Nocardia farcinica. The enzyme consists of four subunits with a total molecular weight of 190 kDa. The polyamidase cleaved amide and ester bonds of water insoluble model substrates like adipic acid bishexylamide and bis(benzoyloxyethyl)terephthalate and hydrolyzed different soluble amides to the corresponding acid. Treatment of polyamide 6 with this...
Enzymatic hydrolysis of PTT polymers and oligomers
Eberl, A.; Heumann, Sonja; Kotek, R.; Kaufmann, F.; Mitscher, S.; Paulo, Artur Cavaco; Gübitz, Georg M.Article in Press ; Oligomers and polymers (film, fabrics) of the linear aromatic polyester poly(trimethylene terephthalate) (PTT) were treated with polyesterases from Thermomyces lanuginosus, Penicillium citrinum, Thermobifida fusca and Fusarium solani pisi. The cutinase from T. fusca was found to release the highest amounts of hydrolysis products from PTT materials and was able to open and hydrolyse a cyclic ...
Surface hydrolysis of polyamide with a new polyamidase from Beauveria brongniartii
Almansa, Eva; Heumann, Sonja; Eberl, A.; Kaufmann, F.; Paulo, Artur Cavaco; Gübitz, Georg M.Twelve fungi were screened for the potential of their extracellular enzymes to increase the hydrophilicity of polyamide (PA) materials. The most pronounced increase in hydrophilicity was found for enzymes from Beauveria brongniartii and B. bassiana. The 55 kDa polyamidase from B. brongniartii was purified using ultrafiltration, anion exchange chromatography and size exclusion chromatography. This polyamidase wa...
Surface hidrolysis of polyacrylonitrile with nitrile hydrolysing enzymes from ...
Fischer-Colbrie, Gudrun; Matamá, Maria Teresa; Heumann, Sonja; Martinkova, Ludmila; Paulo, Artur Cavaco; Gübitz, Georg M.A new Micrococcus luteus strain BST20 was isolated with ability to metabolize PAN polymers as sole carbon source. Out of seven synthetized PAN copolymers containing different moieties of acrylic acid and/or vinyl acetate the polymer with lowest crystallinity (PAN with 5% vinyl acetate) was most easily metabolized. 13C labelled PAN was completely converted to the acrylic acid by this strain. M. luteus BST20 prod...
New model substrates for enzymes hydrolysing polyethyleneterephthalate and poly...
Heumann, Sonja; Eberel, Anita; Pobeheim, Herbert; Liebminger, Stefan; Fischer-Colbrie, Gudrun; Almansa, Eva; Paulo, Artur Cavaco; Gübitz, Georg M.Recently the potential of enzymes for surface hydrophilisation and/or functionalisation of polyethyleneterephthalate (PET) and polyamide (PA) has been discovered. However, there was no correlation between enzyme class/activity (e.g. esterase, lipase, cutinase) and surface hydrolysis of these polymers and consequently no simple assay to estimate this capability. Enzymes active on the model substrates bis (benzoy...
Specificities of a chemically modified laccase from trametes
Schroeder, M.; Heumann, Sonja; Silva, Carla J. S. M.; Paulo, Artur Cavaco; Gübitz, Georg M.Laccases could prevent fabrics and garments from re-deposition of dyes during washing and finishing processes by degrading the solubilized dye. However, laccase action must be restricted to solubilized dye molecules thereby avoiding decolorization of fabrics. Chemical modification of enzymes can provide a powerful tool to change the adsorption behaviour of enzymes on water insoluble polymers. Polyethylene glyco...
New enzymes with potential for PET surface modification
Fischer-Colbrie, Gudrun; Heumann, Sonja; Liebminger, Stefan; Almansa, Eva; Paulo, Artur CavacoThis work describes newly isolated organisms and their potential to modify the surface of polyethylene terephthalate (PET). Out of the different screening processes, four bacterial and five fungal strains were isolated. A PET model substrate was synthesized (bis (benzoyloxyethyl) terephthalate) and used in the screening process, mimicking the polymer in its crucial properties and having the advantage of defined...
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