Conversion of cellulose to sugars and cellobionic acid by the extracellular enzyme system of Chaetomium cellulolyticum

1982 ◽  
Vol 4 (12) ◽  
pp. 775-780 ◽  
Author(s):  
P. F�hnrich ◽  
K. Irrgang
Keyword(s):  
Enzyme System ◽  
Extracellular Enzyme ◽  
Cellobionic Acid

scholarly journals Characterization of a cellobiose dehydrogenase in the cellulolytic fungus Sporotrichum (Chrysosporium) thermophile

1982 ◽  
Vol 203 (1) ◽  
pp. 277-284 ◽  
Author(s):  
M R Coudray ◽  
G Canevascini ◽  
H Meier
Keyword(s):  
Methylene Blue ◽  
Extracellular Enzyme ◽  
Electron Acceptors ◽  
Cellobiose Dehydrogenase ◽  
Ph Optimum ◽  
Phenazine Methosulphate ◽  
Reduced Activity ◽  
Cellobionic Acid

An extracellular enzyme from culture filtrates of Sporotrichum (Chrysosporium) thermophile (A.T.C.C. 42 464) after growth on cellulose or cellobiose was shown to oxidize cellobiose to cellobionic acid in vitro. Lactose and cellodextrins were also efficiently oxidized, but the enzyme was not active against most mono- and di-saccharides. Several redox substances could act as electron acceptors, but molecular oxygen, tetrazolium salts and NAD(P) were not reduced. Activity was stimulated up to 2-fold in the presence of 0.05 M-Mg2+. The pH optimum of the enzymic reaction was acidic when the activity was tested with dichlorophenol-indophenol or Methylene Blue, but was neutral to alkaline for 3,5-di-t-butyl-1,2-benzoquinone or phenazine methosulphate as electron acceptors. As the enzyme was formed inductively in parallel with the endocellulase, its possible function in relation to cellulolysis is discussed.

DEGRADATION OF RUTIN BY ASPERGILLUS FLAVUS. FACTORS AFFECTING PRODUCTION OF THE ENZYME SYSTEM

1961 ◽  
Vol 7 (1) ◽  
pp. 33-44 ◽  
Author(s):  
D. W. S. Westlake ◽  
F. J. Simpson
Keyword(s):  
Calcium Carbonate ◽  
Aspergillus Flavus ◽  
Extracellular Enzymes ◽  
Enzyme System ◽  
Synthetic Medium ◽  
Extracellular Enzyme ◽  
Factors Affecting ◽  
Higher Temperature

A synthetic medium containing 0.4% rutin, 0.3% (NH4)2HPO4, 0.1% KH2PO4, 0.1% MgCl2∙6H2O, and 0.8% (NH4)2SO4was developed for the production of the extracellular enzyme system that degrades rutin. The total amount of the enzyme system produced is approximately the same between 25 and 35 °C but the rate is more rapid at the higher temperature. Aeration is necessary both for synthesis and for excretion into the medium, excretion apparently being more sensitive than synthesis. Magnesium is required for growth and sulphate for release of the enzyme system into the medium. Calcium carbonate depresses both growth and production. The medium has been successfully employed for production in 5-gallon fermentors of the extracellular enzymes that degrade rutin.

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