TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preparation (Disclosed): The genetically modified microorganism is produced by standard recombinant methods. Preferred Microorganism: The one or more heterologous polynucleotides encode one or more low temperature-adapted enzymes of psychrophile microorganism. The genetically modified microorganism produces more first fermentation end-products after incubation with biomass at first temperature and has more specific cellulase activity/cellular mass than microorganism of the same strain and species that is not genetically modified to express one or more low temperature-adapted enzymes. The heterologous polynucleotides encode cellulase or xylanase. The genetically modified microorganism does not express pyruvate decarboxylase. Preferred Enzyme: The low temperature-adapted enzymes are chosen from cellulase, xylanase, hemicellulase, endoglucanase, exoglucanase, cellobiohydrolase (CBH), beta -glucosidase, glycoside hydrolase, glycosyltransferases, lyase, esterase, chitinase, pectinase and their combinations. The one or more low temperature-adapted enzyme is catalytic domain in endoglucanase G (CelG). The CelG is isolated from Pseudoalteromonas haloplanktis. Preferred System: The biomass is pre-conditioned with acid treatment, alkali treatment or steam explosion. The biomass comprises one or more of xylan, cellulose, hemicellulose, lignocellulose, pectin, or xylose, and corn steep solids, corn steep liquor, malt syrup, corn stover, bagasse, algae, fruit peels, oat hulls, modified crop plants, poplar, wood, switch grass, distiller's grains, paper and paper pulp sludge, municipal waste, plant material, plant material extract, natural or synthetic polymer and their combinations. The process of producing fermentation end-product is carried out at 10-35 degrees C. SPECIFIC MICROORGANISMS - Only one genetically modified microorganism is specifically claimed, i.e. mesophilic or thermophilic Clostridium phytofermentans strain C.Q.D or its variant.    EXAMPLE - No suitable example given.