Antibiotics (Gold Biotechnology) were used at the following working concentrations: carbenicillin 50 μg/mL, spectinomycin 50 μg/mL, chloramphenicol 25 μg/mL, kanamycin 50 μg/mL, tetracycline 10 μg/mL, streptomycin 50 μg/mL. HyClone water (GE Healthcare Life Sciences) was used for PCR reactions and cloning. For all other experiments, water was purified using a MilliQ purification system (Millipore). Phusion U Hot Start DNA polymerase (Thermo Fisher Scientific) was used for all PCRs. Plasmids and SPs were cloned by USER assembly21 (link). Genes were obtained as synthesized gBlock gene fragments from Integrated DNA Technologies or PCR amplified directly from E. coli genomic DNA. Plasmids were cloned and amplified using either Mach1 (Thermo Fisher Scientific) or Turbo (New England BioLabs) cells. Unless otherwise noted, plasmid or SP DNA was amplified using the Illustra Templiphi 100 Amplification Kit (GE Healthcare Life Sciences) prior to Sanger sequencing. A full list of plasmids used in this work is given in Supplementary Table 5. A full list of reagents and equipment used in this work is given in Supplementary Table 6.