The filamentous fungus Trichoderma reesei produces and secretes profuse quantities of enzymes that act synergistically to degrade cellulase and related biomass components. We partially sequenced over 5100 random T. reesei cDNA clones. Among the sequences whose predicted gene products had significant similarity to known proteins, 12 were identified that encode previously unknown enzymes that likely function in biomass degradation. Microarrays were used to query the expression levels of each of the sequences under different conditions known to induce cellulolytic enzyme synthesis. Most of the genes encoding known and putative biomass-degrading enzymes were transcriptionally coregulated. Moreover, despite the fact that several of these enzymes are not thought to degrade cellulase directly, they were coordinately overexpressed in a cellulase overproducing strain. A variety of additional sequences whose function could not be ascribed using the limited sequence available displayed analogous behavior and may also play a role in biomass degradation or in the synthesis of biomass-degrading enzymes. Sequences exhibiting additional regulatory patterns were observed that might reflect roles in regulation of cellulase biosynthesis. However, genes whose products are involved in protein processing and secretion were not highly regulated during cellulase induction.

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and the University of California at Riverside, leading pretreatment technologies based on ammonia fiber expansion, aqueous ammonia recycle, dilute sulfuric acid, lime, neutral pH, and sulfur dioxide were applied to a single source of poplar wood, and the remaining solids from each technology were hydrolyzed to sugars using the same enzymes. Identical analytical methods and a consistent material balance methodology were employed to develop comparative performance data for each combination of pretreatment and enzymes. Overall, compared to data with corn stover employed previously, the results showed that poplar was more recalcitrant to conversion to sugars and that sugar yields from the combined operations of pretreatment and enzymatic hydrolysis varied more among pretreatments. However, application of more severe pretreatment conditions gave good yields from sulfur dioxide and lime, and a recombinant yeast strain fermented the mixed stream of glucose and xylose sugars released by enzymatic hydrolysis of water washed solids from all pretreatments to ethanol with similarly high yields. An Agricultural and Industrial Advisory Board followed progress and helped steer the research to meet scientific and commercial needs.

Incorporation of 4.5 nmol fluorescein isothiocyanate/mg rabbit sarcoplasmic reticulum, or of 7.4 nmol/ mg purified ATPase, was sufficient to inhibit the activity completely. These results are not consistent with the suggestion (Pick, U. and Karlish, S.J.D. (1980) Biochim. Biophys. Acta 626, 255-261) that 2 mol ATPase were inhibited by each mole of reagent incorporated. A single labelled peptide was purified from the inhibited ATPase and it was shown that Lys 3/190, 10 residues from the N-terminus of tryptic fragment B, was the reactive lysine residue. This site is close to a potential nucleotide-binding fold in the ATPase sequence. A similar peptide showing only 2 conservative replacements was isolated from the sarcoplasmic reticulum of the lobster. (Ca 2 + + Mg 2 + )A TPase inhibition Reactive lysine residue Fluorescein isothiocyanateIntegral membrane protein Nucleotide-binding fold (Sarcoplasmic reticulum)

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