Foundries & design
Engineering living things means paying for every length: yield per base, DNA's stiffness, specificity per protein contact.
This cluster is about engineering living things, and each of its limits is a price for length or size. DNA synthesis pays geometrically: step yield capitulates over hundreds of bases, so cost per base rules the whole design space. DNA origami runs into the persistence length — the molecule’s stiffness refuses free forms larger than tens of nanometres. Protein design pays for specificity: a handful of contacts cannot encode exclusivity, and membrane proteins still resist computation worse than the rest.
The second motif is standards and their fate: the fixed BioBrick scar solved assembly and created a scar problem (frames and stops in the wrong places), while cheap synthesis retired the need for a physical standard altogether. The third is foundry automation: the design–build–test conveyor does not speed up biology, it speeds up iteration — and the iteration’s limit remains measurement.
Start with metabolic engineering: the cell as a flux network is where design starts.
Articles 9
| Metabolic engineering A production strain is a redirected metabolic network: flux logic decides what is possible, intermediate chemistry decides what is stable, and the host's regulation fights every intervention. |
| DNA synthesis and gene foundries Writing DNA means adding one base at a time to a chain that only compounds losses: per-step yield, per-base errors and cost per base, not imagination, set what can be designed. |
| Cell-free biosynthesis A lysate is not an ingredient but a metabolism stripped of its envelope: open reactions trade the cell's defences for direct control, and the bill arrives as an energy problem. |
| Generative protein design Design works because folding is a physical free-energy search — write a sequence whose minimum is the shape you want — and fails where the models' learned statistics run out. |
| DNA nanotechnology and origami Base pairing turns DNA into addressable glue and its duplex into a semi-rigid rod: what folds, how big, and how cleanly, is set by persistence length, electrostatics and scaffold length. |
| CAD software for synthetic biology The triage verdict is split: assembly compilation is real engineering with checkable rules, while behavioural simulation is a data problem — parts drift with context, so the library, not the algorithm, is the bottleneck. |
| BioBricks and standard genetic parts The standard encodes two real physical constraints: composition leaves a scar the scissors cannot cut again, and a part's measured behaviour does not travel — the community story sits on top of those. |
| De novo protein design: specifying biology before finding it De novo protein design computes a sequence that folds into a structure performing a chosen function — then builds it and verifies it against the design model. The loop is now institutional, and its translation runs through the biologics and ATMP regulatory frameworks. |
| Toggle switches: memory written in repression Two repressors wired against each other give a cell two stable states; everything from counters to state-dependent therapies is downstream of that double-negative feedback. |