Abstract: The present invention relates to an in vitro produced, artificial cellulosome for enzymatic breakdown of resilient substrates. In particular, the present invention provides a complex having an increased activity on resilient substrates, such as crystalline cellulose. The in vitro formed complex comprises a backbone scaffold having at least four binding sites capable of binding the enzyme components, whereby at least two of the binding sites have essentially the same binding specificity; and at least three different enzyme components being randomly bound to the at least four binding sites. Method for preparing the complex and uses of the same for enzymatic breakdown of resilient substrates are also provided.