The present invention refers to the new 
Escherichia coli strains denominated JU15, JU15A, LL26 and MS04 and their derivatives that produce metabolites, particularly D-lactate, L-lactate or 
ethanol, with high yield and selectivity from a wide variety of carbon sources, such as culture media with a high 
xylose content (as the main 
carbon source) and, in particular, media formulated with hydrolyzed vegetables, such as sugarcane 
bagasse, 
agave bagasse and fast-growing grasses, and a wide variety of agricultural and industrial wastes, such as whey or 
forestry wastes, celluloses, grasses, 
agave bagasse, paper wastes, shavings and 
sawdust, shrubs and generally any material derived from lignocellulose. These strains use the production of the 
metabolite of interest (especially D-lactate, L-lactate or 
ethanol) as the only way of regenerating the reducing power. The invention also refers to 
fermentation methods to produce these metabolites from media with a diversity of carbon sources, including glucose, 
lactose or 
xylose.