RT Journal Article
T1 Coating of Soluble and Immobilized Enzymes with Ionic Polymers: Full Stabilization of the Quaternary Structure of Multimeric Enzymes
A1 Bolívar Bolívar, Juan Manuel
A1 Rocha Martín, Javier
A1 Mateo, Cesar
A1 Cava, Felipe
A1 Berenguer, Jose
A1 Fernandez-Lafuente, Roberto
A1 Guisan, Jose
AB This paper shows a simple and effective way to avoid the dissociation of multimeric enzymes by coating their surface with a large cationic polymer (e.g., polyethylenimine (PEI)) by ionic exchange. As model enzymes, glutamate dehydrogenase (GDH) from Thermus thermophilus and formate dehydrogenase (FDH) from Pseudomonas sp. were used. Both enzymes are very unstable at acidic pH values due to the rapid dissociation of their subunits (half-life of diluted preparations is few minutes at pH 4 and 25 °C). GDH and FDH were incubated in the presence of PEI yielding an enzyme−PEI composite with full activity. To stabilize the enzyme−polymer composite, a treatment with glutaraldehyde was required. These enzyme−PEI composites can be crosslinked with glutaraldehyde by immobilizing previously the composite onto a weak cationic exchanger. The soluble GDH-PEI composite was much more stable than unmodified GDH at pH 4 and 30 °C (retaining over 90% activity after 24 h incubation) with no effect of the GDH concentration in the inactivation course. The composite could be very strongly, but reversibly, adsorbed on cationic exchangers. Similarly, FDH could be treated with PEI and glutaraldehyde after adsorption on cationic exchangers, This permitted a stabilized FDH preparation. In this way, the coating of the enzymes surfaces with PEI is used as a simple and efficient strategy to prevent enzyme dissociation of multimeric enzymes. These composites can be used as a soluble catalyst or reversibly immobilized onto a cationic exchanger (e.g., CM-agarose).
PB American Chemical Society
SN 1525-7797
YR 2009
FD 2009
LK https://hdl.handle.net/20.500.14352/93094
UL https://hdl.handle.net/20.500.14352/93094
LA eng
NO Bolivar, J. M., Rocha-Martin, J., Mateo, C., Cava, F., Berenguer, J., Fernandez-Lafuente, R., & Guisan, J. M. (2009). Coating of soluble and immobilized enzymes with ionic polymers: Full stabilization of the quaternary structure of multimeric enzymes. Biomacromolecules, 10(4), 742-747. https://doi.org/10.1021/BM801162E
NO Comunidad de Madrid
NO Ministerio de Ciencia y Educación (España)
NO Fundacion Ramon Areces
DS Docta Complutense
RD 22 abr 2025