TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Composition: In the composition, the variant Cel5a endoglucanase has a T50 above 70 degrees C. The variant Cel5a endoglucanase has a T50 of about 1 degrees C to about 17 degrees C. above the T50 of the wild type Cel5a. The increase in enzymatic activity is a net activity increase in amount of digested cellulose relative to the wild type. The enzymatic activity is measured using a cellobiose activity assay. The variant Cel5a endoglucanase comprises a single point mutation in the Cel5a amino acid sequence selected from Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn153Asp, Asn155Glu, Thr156Glu, Gly189Ser, Phe191Val, Thr233Val, Gly239Glu, Val265Thr, Asp271Tyr, Gly293Ala, Ser309Trp/Leu, and Ser318Pro/Gln/Glu. It comprises a combination of point mutations in the Cel5a amino acid sequence, the combination of point mutations being selected from Gly189Ala, Phe191Val, Gly239Asp, Ser242Ala, Val265Thr, Asp271Tyr, Ser318Pro/Glu, and Ser322Ala; Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Gly239Glu, Asp271Tyr, Gly293Ala, Ser309Leu, and Ser318Pro; Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Gly239Glu, Asp271Tyr, Gly293Ala, Ser309Trp, and Ser318Pro; Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Gly239Glu, Asp271Tyr, Gly293Ala, Ser309Leu, and Ser318Glu; Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Gly239Glu, Asp271Tyr, Gly293Ala, Ser309Trp, and Ser318Glu; and Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Phe191Val, Thr233Val, Gly239Glu, Val265Thr, Asp271Tyr, Gly293Ala, Ser309Trp, and Ser318Pro. The point mutation comprises a combination of mutations selected from sn76Pro and Ser139Pro; Thr57Asn, Asn76Pro, Ser139Pro, and Asn155Glu; Thr57Asn, Asn76Pro, Ser139Pro, Asn155Glu, and Gly189Ser; Thr57Asn, Asn76Pro, Ser139Pro, Asn155Glu, and Lys219Gln; Thr57Asn, Asn76Pro, Ser139Pro, Asn155Glu, and Gly239Asn; Thr57Asn, Asn76Pro, Ser139Pro, Asn155Glu, and Asp271Phe; Thr57Asn, Asn76Pro, Ser139Pro, Asn155Glu, Asp271Phe, and Tyr278Phe; Thr57Asn, Asn76Pro, Ser139Pro, Asn155Glu, Gly189Ser, and Lys219Gln; Thr57Asn, Asn76Pro, Ser139Pro, Asn155Glu, Gly189Ser, and Gly239Asn; Thr57Asn, Asn76Pro, Ser139Pro, Asn155Glu, Gly189Ser, Lys219Gln, and Gly239Asn; Thr57Asn, Asn76Pro, Ser139Pro, Asn155Glu, Gly189Ser, Asp271Phe, and Tyr278Phe; Thr57Asn, Asn76Pro, Ser139Pro, Asn155Glu, Gly189Ser, Asp271Phe, Tyr278Phe, and Gly293Ala; Thr57Asn, Asn76Pro, Thr80Glu; Ser139Pro, Asn155Glu, Gly189Ser, Asp271Phe, Tyr278Phe, and Gly293Ala; Thr57Asn, Asn76Pro, Ser139Pro, Asn155Glu, Gly189Ser, Lys219Gln, Gly239Asn, Asp271Phe, Tyr278Phe, and Gly293Ala; Thr57Asn, Asn76Pro, Thr80Glu, Ser139Pro, Asn155Glu, Gly189Ser, Lys219Gln, Gly239Asn, Asp271Phe, Tyr278Phe, and Gly293Ala; Thr57Asn, Asn76Pro, Thr80Glu, Ser139Pro, Asn155Glu, Gln189Ser, Lys219Gln, Gly239Asn, Asp271Phe, Tyr278Phe, Gly293Ala, and Ser318Pro; Thr57Asn, Asn76Pro, Thr80Glu, Ser139Pro, Asn155Glu, Gln189Ser, Lys219Gln, Gly239Asn, Asp271Phe, Tyr278Phe, Gly293Ala, S309F, and Ser318Pro; Thr80Glu, Ser133Arg, Asn155Glu, Gly239Glu, Tyr278Phe, and S318Q; Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Gly239Glu, Asp271Tyr, Gly293Ala, Ser309Leu, and Ser318Pro; Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Gly239Glu, Asp271Tyr, Gly293Ala, Ser309Trp, and Ser318Pro; Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Gly239Glu, Asp271Tyr, Gly293Ala, Ser309Leu, and Ser318Glu; Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Gly239Glu, Asp271Tyr, Gly293Ala, Ser309Trp, and Ser318Glu; Gly189Ala, Phe191Val, Gly239Asp, Ser242Ala, Val265Thr, Asp271Tyr, Ser318Pro/Glu, and Ser322Ala; and Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Phe191Val, Thr233Val, Gly239Glu, Val265Thr, Asp271Tyr, Gly293Ala, Ser309Trp, and Ser318Pro. The point mutation comprises a combination of mutations selected from Thr80Glu, Ser133Arg, Asn155Glu, Gly239Glu, Tyr278Phe, and S318Q; Gly189Ala, Phe191Val, Gly239Asp, Ser242Ala, Val265Thr, Asp271Tyr, Ser318Pro/Glu, and Ser322Ala; Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Gly239Glu, Asp271Tyr, Gly293Ala, Ser309Leu, and Ser318Pro; Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Gly239Glu, Asp271Tyr, Gly293Ala, Ser309Trp, and Ser318Pro; Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Gly239Glu, Asp271Tyr, Gly293Ala, Ser309Leu, and Ser318Glu; Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Gly239Glu, Asp271Tyr, Gly293Ala, Ser309Trp, and Ser318Glu; and Glu53Asp, Thr57Asn, Ser79Pro, Thr80Glu, Val101Ile, Ser133Arg, Asn155Glu, Gly189Ser, Phe191Val, Thr233Val, Gly239Glu, Val265Thr, Asp271Tyr, Gly293Ala, Ser309Trp, and Ser318Pro. Preferred Method: Hydrolyzing occurs at a temperature of about 60 degrees C. to about 70 degrees C. In expressing variant Cel5a endoglucanase protein, the host organism belongs to a genus selected from Saccharomyces, Pichia, Trichoderma, and Aspergillus. EXAMPLE - No suitable example given.