NOVELTY - A polypeptide having cellobiohydrolase II activity is new.    USE - In the production of biofuels and for the synthesis of platform chemicals and/or biopolymers from renewable sources (claimed).    ADVANTAGE - The polypeptide have at least one improved property as compared to the polypeptide of (SEQ ID NO: 1), where the improved property is selected from increased specific activity; decreased sensitivity to at least one proteases; increased thermal activity; increased thermal stability, increased stability in an acidic pH, enhanced stability in a basic pH, where the improved property is an increased specific activity as compared to the polypeptide of (SEQ. ID NO: 1). The improved property is an increased specific activity in avicellulose hydrolysis, wheat straw hydrolysis and/or glucan hydrolysis.    DETAILED DESCRIPTION - A polypeptide (P1) having cellobiohydrolase II activity is new. The polypeptide (P1) containing an amino acid sequence that varies from the amino acid sequence of the wild type CBHII from Trichoderma reesei having 471 amino acid sequence (SEQ ID NO: 1) as given in the specification, where the amino acid sequence of the polypeptide comprises at least one variation as compared with (SEQ ID NO: 1), and at least one variation occurs at a position selected from positions 37, 38, 53, 54, 65, 66 and/or 438 of (SEQ ID NO: 1), where each of at least one variations can be the same or different and can comprise a substitution, deletion or insertion; and the polypeptide (P1) containing a conserved 34 amino acid sequence motif of GlnCys1GlyGlyX1X2X3X4GlyX5X6X7Cys2X8X9GlyX10X11Cys3X12X13X14AsnX15X16TyrX17GlnCys4X18ProX19X20X21, and a conserved 15 amino acid sequence motif of AspGlyX'1X'2X'3X'4X'5X'6X'7ArgX'8AspX'9X'10Cys, as part of a cellulose binding domain.    X=an amino acid and at least a deletion or substitution is in the position X1, X2, X12, X13, X20 or X21 compared to the corresponding isolated CBHII wild type sequences;    X'1-X'9=any amino acid;    X'10=amino acid except of His, Phe or Thr.    INDEPENDENT CLAIMS are included for the following:    (1) a nucleic acid encoding the polypeptide (P1);    (2) a nucleic acid construct comprising the nucleic acid operably linked to at least one control sequences that direct the production of the polypeptide (P1) in a suitable host;    (3) a vector comprising the nucleic acid or the nucleic acid construct;    (4) a host cell comprising the nucleic acid or the nucleic acid construct;    (5) an enzyme composition comprising at least one polypeptide (P1);    (6) a method of producing a polypeptide having cellobiohydrolase II activity involving culturing the host cell in a suitable culture medium under suitable conditions to produce polypeptides having cellobiohydrolase II activity; and obtaining the produced polypeptides;    (7) a feed additive comprising at least one polypeptide (P1);    (8) a method of treating wood pulp involving contacting the wood pulp with at least one polypeptide (P1);    (9) a method of converting biomass to sugars involving contacting the biomass with at least one polypeptide (P1);    (10) a method of alcohol fermentation involving the use of at least one polypeptide (P1); and    (11) a method for increasing the property of a CBHII involving a) providing a CBHII protein having a conserved amino acid sequence motif as part of the cellulose binding domain; and b) either substitution or deletion of at least one of the amino acid X1, X2, X12, X13, X20, and/or X21; or substitution or deletion of the amino acid X10.    X1-X21=amino acids specific for the provided CBHII.