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Centralized facilities for genetic engineering, or "biofoundries", offer the potential to design organisms to address emerging needs in medicine, agriculture, industry, and defense. The field has seen rapid advances in technology, but it is difficult to gauge current capabilities or identify gaps across projects. To this end, our foundry was assessed via a timed "pressure test", in which 3 months were given to build organisms to produce 10 molecules unknown to us in advance. By applying a diversity of new approaches, we produced the desired molecule or a closely related one for six out of 10 targets during the performance period and made advances toward production of the others as well. Specifically, we increased the titers of 1-hexadecanol, pyrrolnitrin, and pacidamycin D, found novel routes to the enediyne warhead underlying powerful antimicrobials, established a cellfree system for monoterpene production, produced an intermediate toward vincristine biosynthesis, and encoded 7802 individually retrievable pathways to 540 bisindoles in a DNA pool. Pathways to tetrahydrofuran and barbamide were designed and constructed, but toxicity or analytical tools inhibited further progress. In sum, we constructed 1.2 Mb DNA, built 215 strains spanning five species (Saccharomyces cerevisiae, Escherichia coli, Streptomyces albidof lavus, Streptomyces coelicolor, and Streptomyces albovinaceus), established two cell-free systems, and performed 690 assays developed in-house for the molecules. [ABSTRACT FROM AUTHOR]

Benzylamine is a commodity chemical used in the synthesis of motion-sickness treatments and anticonvulsants, in dyeing textiles, and as a precursor to the high-energy propellant CL-20. Because chemical production generates toxic waste streams, biosynthetic alternatives have been explored, recently resulting in a functional nine-step pathway from central metabolism (phenylalanine) in E. coli . We report a novel four-step pathway for benzylamine production, which generates the product from cellular phenylpyruvate using enzymes from different sources: a mandelate synthase ( Amycolatopsis orientalis ), a mandelate oxidase ( Streptomyces coelicolor ), a benzoylformate decarboxylase ( Pseudomonas putida ), and an aminotransferase ( Salicibacter pomeroyi ). This pathway produces benzylamine at 24 mg/L in 15 h (4.5% yield) in cultures of unoptimized cells supplemented with phenylpyruvate. Because the yield is low, supplementation with pathway intermediates is used to troubleshoot the design. This identifies conversion inefficiencies in the mandelate synthase-mediated synthesis of ( S )-mandelic acid, and subsequent genome mining identifies a new mandelate synthase ( Streptomyces sp. 1114.5) with improved yield. Supplementation experiments also reveal native redirection of ambient phenylpyruvate away from the pathway to phenylalanine. Overall, this work illustrates how retrosynthetic design can dramatically reduce the number of enzymes in a pathway, potentially reducing its draw on cellular resources. However, it also shows that such benefits can be abrogated by inefficiencies of individual conversions. Addressing these barriers can provide an alternative approach to green production of benzylamine, eliminating upstream dependence on chlorination chemistry.

The ability to quickly and reliably assemble DNA constructs is one of the key enabling technologies for synthetic biology. Here we define a new Biopart Assembly Standard for Idempotent Cloning (BASIC), which exploits the principle of orthogonal linker based DNA assembly to define a new physical standard for DNA parts. Further, we demonstrate a new robust method for assembly, based on type IIs restriction enzyme cleavage and ligation of oligonucleotides with single stranded overhangs that determine the assembly order. It allows for efficient, parallel assembly with great accuracy: 4 part assemblies achieved 93% accuracy with single antibiotic selection and 99.7% accuracy with double antibiotic selection, while 7 part assemblies achieved 90% accuracy with double antibiotic selection. The linkers themselves may also be used as composable parts for RBS tuning or the creation of fusion proteins. The standard has one forbidden restriction site and provides for an idempotent, single tier organization, allowing all parts and composite constructs to be maintained in the same format. This makes the BASIC standard conceptually simple at both the design and experimental levels.

R2oDNA Designer is a web application that stochastically generates orthogonal sets of synthetic DNA sequences designed to be biologically neutral. Biologically neutral sequences may be used for directing efficient DNA assembly by overlap-directed methods, as a negative control for functional DNA, as barcodes, or potentially as spacer regions to insulate biological parts from local context. The software creates optimized sequences using a Monte Carlo simulated annealing approach followed by the elimination of sequences homologous to host genomes and commonly used biological parts. An orthogonal set is finally determined by using a network elimination algorithm. Design constraints can be defined using either a web-based graphical user interface (GUI) or uploading a file containing a set of text commands.