In nature, the plant-based organic carbon contained within plant cell walls is mainly recycled by the action of cellulolytic microorganisms, such as bacteria and fungi, which produce complex arrays of cell wall-degrading enzymes. Many of the enzymes that degrade plant cell wall polysaccharides are modular proteins, which contain single or multiple copies of both catalytic domain(s) and CBM(s). Thus, substrate is attacked by different enzymes acting together at different regions, and much more than sum of individual different enzymatic activities, synergism drives the efficiency of such system. Furthermore, in the case of the cellulosome, a large multi-component cell-bound structures, enzymes are localized at close distance to each-other. The benefits of this spatial proximity on the efficiency of the enzymatic reaction are still poorly understood. We investigate this question by using an in-house developed system, Jo-In, where enzymes are immobilized with controlled densities - therefore distances - that can be controlled precisely. The enzyme used is a xylanase that participates to the hydrolysis of plant cell wall polymers, the Xyn11A from Neocallimastix patriciarum. Our approach preserved the intrinsic activity of the enzyme, making the density of grafting the only parameters that is tuned1.