Fungal secondary metabolites have a long history as antibiotic agents. One prominent example is penicillin. Novel antibiotics are often based on cyclic depsipeptides (CDPs). However, the production of these antibiotics on an industrial scale is known to be problematic. A Berlin-based university has developed a solution for this problem. Optimization of the synthesis can be achieved by using fungal expression systems. Expression systems are genetic constructs (a gene encoded by DNA) that are designed to produce a protein, or an RNA (ribonucleic acid), either inside or outside a cell.