Zur Wechselwirkung zwischen einer Penicillium-Cellulase und wasserlöslichen cellulosederivaten

Abstract

Employing anionic and non-ionic cellulose ethers, differing in type of substituent and degree of substitution, as substrates, the pH-profile of enzyme activity and the parameter Km and Vmax of the MICHAELIS-MENTEN kinetics have been determined with Penicillium citrioviride cellulase in an homogeneous system. Within rather wide limits, a linear correlation was found between the DS of the substrate and Km or Vmax, respectively. Also the pH-profile was found to depend on DS mainly, being bimodal at higher DS. On the other hand, no significant difference was observed between anionic and non-ionic cellulose ethers of about the same DS with regard to the parameters determined. It is assumed, that substrate-enzyme interaction is governed mainly by the length of non-derivatized chain sequences mainly and not by Coulomb interactions.