Updated project metadata. The bacterial secondary metabolite prodigiosin has been shown to exert anticancer, antimalarial, antibacterial and immunomodulatory properties. With regard to cancer, it has been reported that it affects tumor cells but not non-malignant cells, making it a promising lead compound for anticancer drug discovery. However, a direct protein target has not yet been experimentally identified. Here, we identify the Golgi stacking protein GRASP55 as effector target protein of prodigiosin and found evidence that GRASP55 knockout cells show an altered pattern on secreted proteins upon prodigionsin treatment.