Bacterial Production of Custom Sequence and Length ssDNA

Methods and compositions for bacterial production of pure single-stranded DNA (ssDNA) composed of custom sequence and size have been developed. The methods enable scalability and bio-orthogonality in applications of scaffolded DNA origami, offering one-step purification of large quantities of pure ssDNA amendable for immediate folding of DNA nanoparticles. The methods produce pure ssDNA directly from bacteria. In some embodiments the E. coli helper strain M13cp combined with a phagemid carrying only an f1-origin allows for, without the need for additional purification from contaminating dsDNA. This system is useful for generalized circular ssDNA synthesis, and here is applied to the assembly of DNA nanoparticles folded both in vitro and direct from phage.