NOVELTY - An isolated variant of a parent cellobiohydrolase (CBH) enzyme, is new. The variant has cellulase activity, at least 80% sequence homology to 497 amino acid sequence (SEQ ID NO: 3) fully defined in the specification, and significantly improved performance in phosphoric acid swollen cellulose (PASC) assay.    USE - The isolated variant is useful for preparing detergent composition and feed additive. The method (M2) is useful for hydrolyzing a cellulosic substrate, preferably lignocellulosic biomass chosen from grass, switch grass, cord grass, rye grass, reed canary grass, Miscanthus, sugar-processing residues, sugarcane bagasse, agricultural wastes, rice straw, rice hulls, barley straw, corn cobs, cereal straw, wheat straw, canola straw, oat straw, oat hulls, corn fiber, stover, soybean stover, corn stover, forestry wastes, wood pulp, recycled wood pulp fiber, paper sludge, sawdust, hardwood, softwood, and their combinations. The method (M3) is useful for producing a cell culture supernatant (all claimed).    ADVANTAGE - The isolated variant has significantly improved performance in PASC assay, cellulase activity and improved properties for converting cellulosic materials to monosaccharides, disaccharides, and polysaccharides, altered temperature-dependent activity profiles, thermostability, pH activity and stability, substrate specificity, product specificity, and chemical stability.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) an isolated polynucleotide comprising a polynucleotide sequence encoding a variant of a parent CBH polypeptide;    (2) a vector comprising the isolated polynucleotide;    (3) host cell comprising the isolated polynucleotide and vector;    (4) method (M1) of producing the variant CBH polypeptide;    (5) detergent composition comprising a surfactant and the variant CBH polypeptide;    (6) feed additive comprising the variant CBH polypeptide;    (7) method (M2) for hydrolyzing a cellulosic substrate involves contacting the substrate with the isolated variant CBH polypeptide, host cell or their combination;    (8) cell culture supernatant comprising the CBH variant; and    (9) method (M3) of producing a cell culture supernatant comprising a CBH variant involves culturing the host cell under suitable conditions to express the CBH variant and collecting the cell culture supernatant of the culture.