K. Sode et al., STABILIZATION OF PYRROLOQUINOLINE QUINONE GLUCOSE-DEHYDROGENASE BY CROSS-LINKING CHEMICAL MODIFICATION, Biotechnology letters, 18(9), 1996, pp. 997-1002
Cross-linking chemical modification of pyrroloquinoline quinone (PQQ)
glucose dehydrogenase (GDH) by glutaraldehyde was carried out and its
stability was analyzed. Although native PQQGDH was inactivated within
30 min at a higher temperature than 50 degrees C cross-linked PQQGDH r
etained more than 40% of initial activity even after 30 min of incubat
ion at 54 degrees C. In addition to the increase in thermal stability,
cross-linked PQQGDH gained high EDTA tolerance. The stabilization may
be achieved by increased the rigidity of PQQGDH hole enzyme conformat
ion.