Penicillium cellulase

The second source of biochemicals is molecules excreted from cells such as extracellular enzymes and other organic matter. A typical example is cellulase, which is excreted by fungi such as Penicillium in order to break down wood and woody material into sugars that can be used by the organisms. Other common extracellular enzymes found in soil are ureases and amylases. Often enzymes are associated with clay particles, and in such associations, their activity may be increased, decreased, unchanged, or completely destroyed [15],... 

Similar results were obtained with crude cellulase preparations from Penicillium pinophilum (12). The general applicability of this biospecific chromatography is illustrated by the isolation of the EGD from C. t., cloned in E. c. (Fig. 6). 

Enz5mies Proteases Amylases Cellulases Various Bacilli, e.g. Bacillus licheniformis Bacillus subtilis, Aspergillus oryzae Trichoderma viride, Penicillium pinophilum... 

The proteolysis of cellulases has been previously investigated. Nakayama et al. (14) found that mild proteolysis of endoglucanase from T. reesei by a protease prepared from the same fungus resulted in cellulase enzymes which still possessed cellulolytic activity. Earlier, Eriksson and Petterson (24) investigated the effect of various proteolytic enzymes on the cellulase activities on Penicillium notatum. They found that different proteases affected enzyme activities to different degrees. 

Several microorganisms have been studied with respect to the production of a cellulolytic enzyme system for the saccharification of cellu-losic materials, the most thoroughly investigated organism and best producer of cellulase being Trichoderma viride (I). Recently, good saccharification data have been reported using a strain of Penicillium (2). 

Oxidation of two out of 13 tryptophan residues in a cellulase from Penicillium notatum resulted in a complete loss of enzymic activity (59). There was an interaction between cellobiose and tryptophan residues in the enzyme. Participation of histidine residues is also suspected in the catalytic mechanism since diazonium-l-H-tetrazole inactivated the enzyme. A xylanase from Trametes hirsuta was inactivated by N-bromosuc-cinimide and partially inactivated by N-acetylimidazole (60), indicating the possible involvement of tryptophan and tyrosine residues in the active site. As with many chemical modification experiments, it is not possible to state definitively that certain residues are involved in the active site since inactivation might be caused by conformational changes in the enzyme molecule produced by the change in properties of residues distant from the active site. However, from a summary of the available evidence it appears that, for many / -(l- 4) glycoside hydrolases, acidic and aromatic amino acid residues are involved in the catalytic site, probably at the active and binding sites, respectively. 

Many fungi are capable of producing extracellular enzymes that can degrade cellulose. They are Trichoderma (T) reesei, T. viride, T. koningii, T. lignorum, Penicillium funiculosum, Fusarium solani, Sclerotium rolfsii, and so on. Bacterial species such as Cellulomonas along with Clostridium thermocellum can also produce cellulases (Marsden and Gray, 1986). 

The main metabolites of this group of fungi (Fusarium, Aspergillus, Penicillium, and Alternaria) are not only mycotoxins but also hormonally active compounds as well as enzymes, for instance amylase, chitinase, cellulase, glucanase, xylanase, or protease (Pawelzik et al. 1998). 

Despite of their lack in hydrolytic activity, the CBDs of the cellulases CenA and Cex from C. fimi have been found to be capable of disrupting cotton fibers and releasing small particles from the substrate (Kilburn et al., 1993 Din et al., 1994a). This disruptive effect does not seem to be a general characteristic of CBM, since it was only found with CBD from cellulose from a Penicillium sp. (Gao et al., 2001). Anyhow, a synergism with the catalytic module and enhanced degradation capacity were reported (Din et al., 1994a). 

Claeyssens, M., van Tilbeurgh, H., Tomme, R, Wood, T.M., and McCrae, S. I., Fungal cellulase systems Comparison of the specificities of the cellobiohydrolases isolated from Penicillium pinophilum and Trichoderma reesei. Biochem. J. 1989,261, 819-826. 

This appHcation is carried out with the crude cellulases of Trichoderma, Aspergillus, and Penicillium. The digestive process and action of cellulase in the... 

Figure 7. Proteolytic degradation of a cellulase from the fungus Penicillium notatum at pH 7.7 and 30°C. by the endopeptidases, trypsin (O), subtilisin (A), and pronase (%) (9)...

Figure 8. Gel filtration on Sephadex G-75 of a subtilisin-digested cellulose from the fungus Penicillium notatum. Void volume, 150 ml. absorbancy at 280 n.m. (O) absorbancy at 570 n.m., ninhydrin reaction (A) cellulase activity...

Figure 4. Change of the degree of polymerization by enzyme action. Penicillium variable cellulase—wood pulp system (2)...

Penicillium pusillum (Table I), but cellobiose is a good inhibitor of cellulases of many origins. Glucose inhibition is generally weak. For T. viride cellulases acting on heat treated cellulose, a concentration of 30% glucose gives only 40% inhibition (3, 4). 

Table I. Inhibition of Penicillium pusillum Cellulase by Sugars (20)...

Keywords Penicillium decumbens Wheat bran Biomass Cellulase - Xylanase... 

It had shown that the regulation of eellulase formation was significantly different between Penicillium and Trichoderma [16], In T. reesei and P. purpurogenum, the inducers are sophorose and gentiobiose, respectively. In P. purpurogenum, eonstitutive cellulase... 

Vazquez-Flota et al. (336) studied the effect of chitinase, macerozyme, and cellulase on hairy root cultures of C. roseus. No major change in catharanthine levels was observed more ajmalicine was excreted to the medium compared with the control, and the total alkaloid levels were similar. With fungal elicitors no significant changes could be observed in the alkaloid production or excretion of the hairy roots. Only Aspergillus preparations caused some increase of the ajmalicine production. However, methyl jasmonate did effect the production (see later discussion). On the other hand, it was reported that elicitation with Penicillium species enhanced both production and secretion of alkaloids in hairy root cultures of C. roseus (338). Particularly in combination with in situ adsorption on the Amberlite resin XAD-7, a considerable increase of production and release of ajmalicine and catharanthine by the hairy roots was observed, compared with controls. The vindoline pathway is not affected by elicitation (242,244). 

Penicillium funiculosum [26] Xyianse, glucoamylase, pectinase, cellulase, cellobiase. 

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