NOVELTY - Isolated polynucleotide encoding a recombinant scaffolding polypeptide comprising at least a signal peptide, a cellulose binding domain, two cohesin domains and a S-layer homology (SLH) domain, is new, where the recombinant scaffolding polypeptide comprises 2-8 cohesin domains.    USE - The isolated polynucleotide is useful in recombinant bacterium for degrading crystalline cellulose (all claimed), which is useful as a substrate for biorefinery strategies that produce high-value products (including chemicals, fuels, bioplastics and enzymes) through fermentation processes.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for:    (1) a vector comprising a polynucleotide;    (2) a polypeptide comprising at least a signal peptide, a cellulose binding domain, two cohesin domains and a S-layer Homology domain;    (3) a recombinant bacterium transformed with or containing a polynucleotide or a vector;    (4) a recombinant bacterium, where the bacterium expresses the recombinant scaffolding polypeptide, and preferably further expresses at least a recombinant endoglucanase that binds to the recombinant scaffolding protein through a cohesin domain, at least a recombinant exoglucanase that binds to the recombinant scaffolding protein through another cohesin domain, and/or a recombinant beta -glycosidase;    (5) degrading a cellulosic bio mass using a recombinant lactic acid bacterium;    (6) producing lactic acid from a cellulosic biomass using a recombinant lactic acid bacterium, comprising (a) contacting the cellulosic biomass with the recombinant lactic acid bacterium in conditions suitable for culturing and/or growing the recombinant lactic acid bacterium and (b) culturing the recombinant lactic acid bacterium for producing lactic acid, and optionally (c) collecting the resulting lactic acid;    (7) a co-culture of at least two recombinant bacteria, at least one recombinant lactic acid bacterium expressing a scaffolding polypeptide, and at least one recombinant bacterium expressing cellulosomal enzyme, preferably an endoglucanase and/or an exoglucanase and/or a beta -glycosidase; and    (8) a fermentation tank, such as a bioreactor or a chemostat, comprising a cellulosic biomass and a recombinant lactic acid bacterium.