Rhizopus niveus glucoamylase from

Fig, 3,—Action of Rhizopus niveus Glucoamylase (free from oIpho-Amylase)... 

Kitahara, K., Suganuma, T., and Nagahama, T. 1996. Susceptibility of amylose-lipid complexes to hydrolysis by glucoamylase from Rhizopus niveus. Cereal Chem., 73(4), 428. 

Glucoamylase from Rhizopus niveus has been shown to have an exo action on (l-> 3)-o - and (1 6)-a-D-glucan linkages as well as on malto-oligo-saccharides. ... 

The hydrolysis of maltose by glucoamylase from Rhizopus niveus was carried out in the presence an d absence of dextran sulphate, which are the components of supports of immobilized enzymes.The interaction between dextran and the enzyme was observed by fluorescence spectrophotometry. The kinetic and fluorescence experiments indicated that dextran became bound to glucoamylase and was apparently a non-competitive inhibitor of the enzyme. The dissociation constant of the enzyme-dextran complex was estimated to be 34%. The reaction rate was hardly affected at pH 4.0 and 4.5 by addition of dextran sulphate, whereas the kinetic parameters depended considerably on the concentration of dextran sulphate at pH 3.5. These findings indicated that there might exist some interactions between the enzyme and dextran sulphate. 

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