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Additional file 5: Figure S4. Hydrolysis of un/pretreated wheat straw. The wild-type PC9 and the two transformants were used as a biological pretreatment of wheat straw for 19 and 35Â days. The pretreated and untreated straw samples were hydrolyzed by the commercial cellulase cocktail CellicÂŽ CTec2 (Novozymes), and the concentration of released soluble sugars was measured by the DNS method [84].

Additional file 1: Figure S1. Purification profile of the different cellulosomes by Gel filtration chromatography. C. thermocellum growth media were centrifuged (10,900Â g, 7Â min), and the supernatant fluids were carefully removed from the pellet and concentrated 40 times using a Pellicon XL biomax 300 cassette (Millipore, Cat. No. PXB300C50). Concentrated samples were fractionated by size exclusion chromatography using a SuperdexS-200 prep grade 16/60 gel filtration column (GE Healthcare). (A) Chromatogram of glucose-derived cellulosomes (B) Chromatogram of CB-derived cellulosomes (C) Chromatogram of MCC-derived cellulosomes (D) Chromatogram of alSG-derived cellulosomes (E) Chromatogram of alCS-derived cellulosomes (F) Chromatogram of acCS-derived cellulosomes. Fractions containing the cellulosomes (according to SDS-PAGE analysis) are marked by black arrows. All cellulosomes-containing fractions were eluted immediately after void value due to the separation range of the column.

Additional file 1. Non-denaturing PAGE analysis of wild-type and mutant forms of Cel48S complexed with the monovalent scaffoldin Scaf¡T. Complexes were produced at different molar ratios and applied to non-denaturing polyacrylamide gels. For each gel, lanes 1 to 7 correspond to the respective enzyme/scaffoldin complexes at the following ratios: 0.4, 0.6, 0.8, 1.0, 1.2, 1.4 and 1.6. (Lane 4 signifies the calculated 1:1 ratio). Lane 8 corresponds to the specified enzyme alone at the presumed molar ratio. Red rectangle indicated the determined exact equimolar ratio.

Additional file 2. Comparative thermostability of wild-type β-glucosidase and BglA*. The enzymes were incubated at 66-72 °C for 1 h at pH 6.1. Residual activity was determined at a protein concentration of 1.05 µg/mL following incubation with 1 mM pNPG (Sigma-Aldrich, Israel) for 10 min at 60°C. Reactions were terminated by 1 M sodium carbonate and optical densities of the samples were measured at 405 nm (pNP released). Residual activities were calculated by dividing the activity of non-heated samples by that of the heated samples. The assay was performed at least twice in triplicate, error bars are indicated. Thermostable BglA* was generated by error-prone PCR as described by Anbar [24] using Gene-Morph II Random Mutagenesis Kit (Stratagene, La Jolla, CA). The thermostable BglA* was selected as it maintained the highest enzymatic activity after heat shock at 70 °C for 50 min (conditions in which the wild-type enzyme was no longer active). BglA* exhibited 127 % activity compared to the wild-type enzyme following heat shock at 66 °C for 75 min, and incubation with 1 mM pNPG for 45 min at 60 °C at 13 nM. Sequencing of the clone revealed 2 mutations: A17S and K268N.