Details

Autor(en) / Beteiligte

• Le Costaouëc, Tinaïg
• Pakarinen, Annukka
• Várnai, Anikó
• Puranen, Terhi
• Viikari, Liisa

Titel

The role of carbohydrate binding module (CBM) at high substrate consistency: Comparison of Trichoderma reesei and Thermoascus aurantiacus Cel7A (CBHI) and Cel5A (EGII)

Ist Teil von

• Bioresource technology, 2013-09, Vol.143, p.196-203

Ort / Verlag

Kidlington: Elsevier Ltd

Erscheinungsjahr

2013

Quelle

Elsevier ScienceDirect Journals

Beschreibungen/Notizen

• •The hydrolytic efficiency of CBM-less cellulases was improved at high consistency.•The CBM-less cellulases of T. aurantiacus outperformed those of T. reesei.•The CBM-less cellulases were even more efficient on lignocellulosic substrates.•Higher amount of CBM-less cellulases remained free after hydrolysis. The role of CBM in two fungal model cellulase systems, consisting of Cel7A and Cel5A, from Trichoderma reesei and Thermoascus aurantiacus, were compared in the hydrolysis of various substrates. For comparison, family-1 CBM’s were introduced to the T. aurantiacus and removed from the T. reesei enzymes. Especially at high dry matter consistencies of lignocellulosic substrates, pretreated wheat straw and spruce, the T. aurantiacus enzymes lacking CBM outperformed the enzymes carrying the CBM. In these conditions, the CBM-less enzymes from both organisms obviously recognized and bound to the substrate at higher probability than in dilute systems. Avoiding the unproductive binding to lignin caused by the CBMs obviously enhanced the hydrolytic performance. The lignin binding effect was, however, not entirely caused by the CBM, but also by the different structures and affinities of the core enzymes to lignin. Due to decreased binding, the CBM-less enzymes would allow reuse, potentially decreasing hydrolysis costs.