Cellulase profile

Figure 14. Change (solid line) in apparent molecular weight distribution of water-soluble extract from a cellulase-treated ezomatsu wood residue (dotted line) at pH 4.0 brought about by the laccase HI preparation from C. versicolor, Sephadex GIO/H2O elution profiles adapted and redrawn from reference 85.

It has been proposed that the production of xylanases and cellulases is under separate regulatory control in some filamentous fungi (1). Hrmova et al. (42) reached a similar conclusion after monitoring the daily production of these enzymes in Trichoderma reesei QM 9414. Xylanase and cellulase activities followed independent production profiles during fungal growth. The same effect has been observed in batch cultures of T. harzianum. We have observed peak xylanase activity on the third day of growth whereas the cellulase activity peaked after day five or six (unpublished). 

Figure 6. pH-activity profile of cellulolytic enzyme activities from Thermoactinomyces sp. under assay conditions. (Q) CM-cellulase, incubation time 10 min (A) Avicelase, incubation time 20 min (O) /3-glu-cosidase, incubation time 30 min. 

Figure 1. Elution profiles of cellulase activity from Sephadex G-100 gel chromatographs of crude extracts of auxin-treated pea apices. BS cellulose activity has an elution volume corresponding to a molecular weight of 20,000. BI cellulase activity dissolves in 1M NaCl and elutes with a molecular weight of 70,000. These values correspond to those observed for purified cellulases (3), indicating that the enzymes were not altered in molecular weight during purification, and could be effectively separated by differential extraction.

Index Entries Cellulase production Trichoderma reesei RUT C30 pH profiling p-glucosidase shake flask fermentor. 

Figure 5 illustrates the performance of immobilized cellulase in comparison with that of soluble cellulase. The small difference between the "crude" and "used" Spezyme CP profiles illustrates the very low uptake of soluble cellulase onto the support. Furthermore, soluble cellulase is much more active the dose of soluble enzyme is approx one-twentieth that of immobilized cellulase, once enzyme uptake is taken into account. Nonetheless, it is important to note that the immobilized enzyme is able to hydrolyze this insoluble substrate, albeit at a much lower rate. 

Immobilization of Aspergillus niger cellulase on a polyacrylonitrile derivative raised the pH optimum of the enzyme by 0.4 units and lowered the temperature optimum by The pH-activity profile of the enzyme also narrowed on... 

In order to establish the relations between the cellulase activities in various strains of Pyricularia oryzae and the optimum pH and between the intra- and extra-cellulases, the gel-filtration profiles of the enzymes have been compared. It appears that some of the molecular properties of one of the cellulase components change on excretion into the culture medium. A number of cellulases from P. oryzae are active at pH > 7. 

Cariola MG, Forni C, Albertano P (1987) Characterization of the algal flora growing on ancient Roman frescoes. Phycologia 26 387-397 Chahal PS, Chahal DS, Andre G (1992) Cellulase production profile of Trichoderma reesei on different cellulosic substrates at various pH levels. J Ferment Bioeng 74 126-128... 

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