NOVELTY - A hybrid enzyme (I) comprising a catalytic module and a carbohydrate-binding module, is new.    USE - (I) or (II) is useful for liquefying starch, where a gelatinized or granular starch substrate is treated in aqueous medium with (I) or (II). The method involves contacting the treated starch with a yeast to produce fuel or potable ethanol. The method involves fermenting the treated starch into a fermentation product, such as citric acid, monosodium glutamate, gluconic acid, sodium gluconate, calcium gluconate, potassium gluconate, glucono delta lactone, sodium erythorbate, itaconic acid, lactic acid, gluconic acid, ketones, amino acids, glutamic acid (sodium monoglutaminate), penicillin, tetracycline, enzymes, vitamins, such as riboflavin, B12, beta-carotene or hormones. The starch slurry is contacted with a polypeptide comprising a carbohydrate-binding module, but not catalytic module. (I) or (II) is useful for preparing a dough-based product, which involves adding (I) or (II) to a dough (all claimed).    DETAILED DESCRIPTION - A hybrid enzyme (I) comprising a catalytic module and a carbohydrate-binding module, is new. The enzyme comprises:    (a) (Ia) a catalytic module having an amino acid sequence at least 70% homologous to SEQ ID NO:8 (511 amino acids) or SEQ ID NO:30 (498 amino acids) and the carbohydrate binding module has a sequence at least 50% homologous to a sequence selected from SEQ ID NOs: 9-25 of 102, 99, 102, 112, 95, 107, 115, 115, 139, 126, 116, 133, 116, 114, 111, 108 or 97 amino acids respectively; or    (b) (Ib) (a sequence having at least 50% homology to) the catalytic domain sequence of the Aspergillus oryzae alpha-amylase comprising amino acids 21-498 of SEQ ID NO:40, and a carbohydrate binding domain.    INDEPENDENT CLAIMS are also included for the following:    (1) a catalytically active variant alpha-amylase (II) having at least 80% homology SEQ ID NO:41 (640 amino acids), where (II) comprises an alteration at one or more of the positions chosen from 13, 15, 18, 31, 32, 33, 34, 35, 36, 61, 63, 64, 68, 69, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 89, 117, 118, 119, 120, 121, 122, 123, 124, 125, 152, 153, 154, 155, 156, 157, 158, 161, 162, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 204, 205, 206, 207, 208, 209, 210, 211, 216, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 242, 245, 250, 252, 253, 255, 256, 257, 259, 260, 275, 292, 295, 296, 297, 298, 299, 304, 328, 339, 344, 348, 378, 383, 386, 387, 405, 448 and 480, where the alteration(s) are independently:    (a) an insertion of an amino acid downstream of the amino acid which occupies the position;    (b) a deletion of the amino acid which occupies the position; or    (c) a substitution of the amino acid which occupies the position with a different amino acid;    (2) an isolated DNA sequence (III) encoding (Ia) or (II)    (3) a DNA construct comprising (III);    (4) an expression vector (IV) comprising (III);    (5) a host cell (V) transformed with (IV), where (V) is capable of expressing (III);    (6) liquefying starch by treating a gelatinized or granular starch substrate with (Ia) or (II); and    (7) preparing a dough-based product by adding the (Ia) or (II) to a dough.