Trichoderma enzyme

In the treatment of cellulose pulps one essential criterion for a suitable enzyme preparation is that its cellulase activity should be as low as possible, or preferably absent completely. As even extremely low cellulase activities may ruin pulp quality, Trichoderma enzyme preparations are unlikely to be suitable for these applications. Many bacterial and fungal enzymes with low cellulase activity have been shown to be suitable for treatment of pulps 14, 15, 16,17), Regulation of the often synchronous production of cellulolytic and hemicellulolytic enzymes in micro-organisms is not well understood, and is further complicated by substrate cross-specificity of these enzymes. Enzymes with both endoglucanase and xylanase activity have been reported for bacteria 18, 19) and fungi 20, 21, 22), In addition to selection of strain and... 

Galante, Y., Conti, A., and Monteverdi, R. 1998a. Applications of Trichoderma enzymes in the food and feed industries. In Harman, G., and Kubicek, C. (Eds.), Trichoderma and Gliocladium, 2 (pp. 327-342). London Taylor and Francis Ltd. 

Figure 1. Hydrolysis of cotton by organisms and by cell-free enzymes (17). Growth tests—Consumption of cellulose by active cellulolytic fungi. Trichoderma enzyme— - weight loss of cellulose). Other enzymes—Cell-free celluloses from organisms other than Trichoderma...

Biely P (1990) Artificial substrate for cellulolytic glycanases and their use for the differentiation of Trichoderma enzymes. In Kubicek CP, Eveleigh DE, Esterbauer H, Sten W, Kubicek-Pranz EM (eds) Trichoderma Cellulases. Biochemistry, Genetics, Physiology and Applications. Royal Chem Soc Cambridge p 30... 

Cellulase-gold was made and applied according to (Berg et al., 1988) with sections from material embedded in Quetol 651. Chromatographically purified cellulase complex from Trichoderma reesei was obtained from Worthington Enzymes (Cat. it CEL). 

This enzyme was shown to be specific for xylan oligomers and small acetylated synthetic substrates. Many characteristics have been published recently about this type of enzyme, purified from Trichoderma reesei, and A. oryzae [6], and a different A. n/ger preparation[7]... 

Sivan, A. and Chet, I. (1989). Degradation of fungal cell walls by Litic enzymes of Trichoderma harzianum , Journal of Genetic Microbiology, 135, 675-682. 

L-Pipecolic acid, a key component of many antibiotic and anticancer biomolecules, serves as an important chiral pharmaceutical intermediate. We have developed an enzyme-coupled system consisting of zl -piperidine-2-carboxylate reductase (Pip2C) from Pseudomonas putida, glucose dehydrogenase (GDH) from Bacillus subtilis, and L-lysine a-oxidase from Trichoderma viride, affording L-pipecolic acid from L-lysine in high yield with an excellent enantioselectivity (Figure 10.2). ... 

Matsumura and Bousch (1966) isolated carboxy lest erase (s) enzymes from the soil fungus Trichoderma viride und a bacterium Pseudomonas sp., obtained from Ohio soil samples, that were capable of degrading malathion. Compounds identified included diethyl maleate, desmethyl malathion, carboxylesterase products, other hydrolysis products, and unidentified metabolites. The authors found that these microbial populations did not have the capability to oxidize malathion due to the absence of malaoxon. However, the major degradative pathway appeared to be desmethylation and the formation of carboxylic acid derivatives. 

There have been a number of reports of the use of enzymes in the extraction of oils from sources such as fish, rape seed, yeast, palms, and soya beans. Celluloses and pectinases are used in pdm oil extraction. In soya bean and fish, much oil has been found to be associated with protein, so that addition of proteases increases the yield of oil and protein. Use of thermostable proteases is preferred, but m general the use of enzymes is limited by the minimal water contents of the various process streams. Trichoderma uride and A niger celluloses, hemicellulases and proteases have been used to extract hydrocarbons from Euphorbia plants 39 40) and similar enzymes used to extract sapogenins from Helleborus 41). 

Wheat straw. Wheat straw ground to 20 mesh was treated with 2% NaOH solution (wt/vol) in 1 2 (solidiliquid) ratio at 121 C for 0.5 h (i.e., 4 g NaOH/100 g wheat straw). Trichoderma reesei QMY-1 was grown on pretreated wheat straw in SSF as well as in LSF under otherwise identical culture conditions. The SSF was carried out with full nutrient concentrations in one set and with one-half nutrient concentrations in the other set to evaluate the possible deleterious effects of elevated osmotic pressure. T reesei QMY-1 produced FP cellulase of 8.6 lU/ml (430 lU/g cellulose or 172 lU/g substrate) in 22 days. This showed that the organism was able to tolerate the high salt concentrations required in the SSF. In contrast, when the nutrients were supplied in one-half concentration, FP cellulase activity dropped to 6.7 lU/ml (335 lU/g cellulose or 134 lU/g substrate). However, the maximum enzyme activity was obtained one week earlier (14 days) than that obtained with full salt concentrations (Table I). 

Teeri, T. The cellulolytic enzyme system of Trichoderma reesei Doctoral Thesis VTT Publications 38 Technical Research Center, Espoo, FL, 1987... 

The core-enzymes, prepared in our laboratory, and containing the active centers, were successfully crystallized (Dr. Jones, Uppsala, communicated) and tertiary structures will be described in the near future. Chemical modification studies on these enzymes are currently being undertaken in our laboratory identification of important catalytic residues and location of the active centers will lead to more functional information on these enzymes. Other cellulases such as some endoglucanases from Clostridium thermocel-lum (EG A, EG B, EG D) (10) and EngA and Exg from Cellulomonas fimi (19) also contain sequences of conserved, terminally located and sometimes reiterated, amino acids. Some of these sequences are preceded by proline-serine rich domains. Thus, a bistructural-bifunctional organization seems to be a rather common feature among cellulases, at least for EngA and Exg from C. fimi and the enzymes from Trichoderma reesei. 

Chromophoric substrates were also used as tools in the study of the binding of several cellulase components to their natural substrates (such as Avicel). This is illustrated here in the investigation of the synergy in binding of CBH I and CBH II from Trichoderma reesei onto Avicel. The enzymes were differentiated with CNPL (see above), which was a substrate only for CBH I (core I). Thus, the amount of CBH II adsorbed when a mixture of both enzymes was added, either simultaneously or sequentionally, to Avicel was calculated from the amount of CBH I bound (activity measurements with CNPL) subtracted from the values for total protein binding (280 nm absorbance reading). The results obtained from these experiments are summarized as follows ... 

Environmental Potential of the Trichoderma Exocellular Enzyme System... 

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