B-Galactosidase was immobilized on nylon/poly(glycidyl methacrylate) membranes through spacers of different length hexamethylenediamine, ethylenediamine or hydrazine. The effect of the spacer length on the catalytic behavior of the three membranes was studied in isothermal bioreactors. The behavior of the soluble and insoluble enzymes was compared to know the effects of the immobilization process and of the spacer length. The enzyme derivatives in comparison with the soluble enzyme exhibited shifts of the optimum pH values towards more acidic solutions. These shifts were found decreasing with the spacer length; while an opposite trend was observed when the optimumtemperature valueswere considered.Also the values of the apparentKm were found to decreasewith the spacer length All these results indicated that a soluble enzyme could be considered as an enzyme immobilized on a solid support through a spacer of infinite length.
Influence of the spacer length on the activity of enzyme immobilized on nylon/ poly GMA membranes. PART 1.ISOTHERMAL CONDITIONS / DE MAIO, Anna; M. M. El Masry M., Portaccio; N., Diano; S., Di Martino; A., Mattei; U., Bencivenga; D. G., Mita. - In: JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC. - ISSN 1381-1177. - ELETTRONICO. - 21:(2003), pp. 239-252.
Influence of the spacer length on the activity of enzyme immobilized on nylon/ poly GMA membranes. PART 1.ISOTHERMAL CONDITIONS.
DE MAIO, ANNA;
2003
Abstract
B-Galactosidase was immobilized on nylon/poly(glycidyl methacrylate) membranes through spacers of different length hexamethylenediamine, ethylenediamine or hydrazine. The effect of the spacer length on the catalytic behavior of the three membranes was studied in isothermal bioreactors. The behavior of the soluble and insoluble enzymes was compared to know the effects of the immobilization process and of the spacer length. The enzyme derivatives in comparison with the soluble enzyme exhibited shifts of the optimum pH values towards more acidic solutions. These shifts were found decreasing with the spacer length; while an opposite trend was observed when the optimumtemperature valueswere considered.Also the values of the apparentKm were found to decreasewith the spacer length All these results indicated that a soluble enzyme could be considered as an enzyme immobilized on a solid support through a spacer of infinite length.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
