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Structure and hierarchical organization are crucial elements of biological systems and are likely required when engineering synthetic biomaterials with life-like behavior. In this context, additive manufacturing techniques like bioprinting have become increasingly popular. However, 3D bioprinting, as well as other additive manufacturing techniques, show limited resolution, making it difficult to yield structures on the sub-cellular level. To be able to form macroscopic synthetic biological objects with structuring on this level, manufacturing techniques have to be used in conjunction with biomolecular nanotechnology. Here, a short overview of both topics and a survey of recent advances to combine additive manufacturing with microfabrication techniques and bottom-up self-assembly involving DNA, are given.

Bioprinting of engineered bacteria is of great interest for applications of synthetic biology in the context of living biomaterials, but so far only few viable approaches are available for the printing of gels hosting liveEscherichia colibacteria. Here we develop a gentle bioprinting method based on an alginate/agarose bioink that enables precise printing ofE.coliinto three-dimensional hydrogel structures up to 10 mm in height. Addition of a calcium peroxide-based oxygen generation system enables maturation of fluorescent proteins deep within the printed structures. We utilize spatial patterning with the bioprinter to control different types of chemical interaction between bacteria. We first show quorum sensing-based chemical communication between engineered sender and receiver bacteria placed at different positions inside the bioprint, and then demonstrate the fabrication of barrier structures defined by non-motile bacteria that can guide the movement of chemotactic bacteria inside a gel.