Recombinant collagen in the era of cellular agriculture.

Collagen is a foundational protein in both native tissues and engineered biomaterials. As cellular agriculture redefines protein production, recombinant collagen (RCOL) is emerging as a viable alternative to animal-derived collagen. RCOL offers molecular control, species-independent scalability, and integration into engineered cell systems. In this context, RCOL supports a closed-loop system: it is both a product of and an enabler for cellular agriculture, powering applications from cultivated meat to regenerative medicine. However, its performance is constrained by post-translational modifications (PTMs), including hydroxylation, glycosylation, and crosslinking, which govern triple-helix stability, fibrillogenesis, and bioactivity. This review discusses emerging strategies (enzyme coexpression, cotranslational incorporation, genetic modification, genetic code expansion, and photo-crosslinking) to bridge the PTM gap and advance RCOL platforms for cellular agriculture.