Useful halophilic, thermostable and ionic liquids tolerant cellulases
The present invention provides for an isolated or recombinant polypeptide comprising an amino acid sequence having at least 70% identity with the amino acid sequence of a Halorhabdus utahensis cellulase, such as Hu-CBH1, wherein said amino acid sequence has a halophilic thermostable and/or thermophilic cellobiohydrolase (CBH) activity. In some embodiments, the polypeptide has a CBH activity that is resistant to up to about 20% of ionic liquids. The present invention also provides for compositions comprising and methods using the isolated or recombinant polypeptide.
1. A composition comprising an isolated or recombinant polypeptide comprising an amino acid sequence having at least 90% identity with the amino acid sequence of SEQ ID NO:1 or SEQ ID NO:5, wherein said isolated or recombinant polypeptide comprises a catalytic domain, a fibronectin domain 3 (FN-3) and an Ig-like domain, and has a halophilic thermostable or thermophilic cellobiohydrolase (CBH) activity and 2-5 M of NaCl, 20-30% of an ionic liquid (IL), or a pH of 7.5 to 12.5.
2. The polypeptide of claim 1 , wherein the amino acid sequence has at least 95% identity with the amino acid sequence of SEQ ID NO:1 or SEQ ID NO:5.
3. The polypeptide of claim 2 , wherein the amino acid sequence has at least 99% identity with the amino acid sequence of SEQ ID NO:1 or SEQ ID NO:5.
4. The polypeptide of claim 3 , wherein the amino acid sequence of the polypeptide comprises the amino acid sequence of SEQ ID NO:1 or SEQ ID NO:5.
5. The composition of claim 1 , comprising 2-5 M of NaCl.
6. The composition of claim 1 , comprising 20-30% of an IL.
7. The composition of claim 1 , comprising a pH of 7.5 to 12.5.