Pro-Xylane is highly valued in cosmetic and dermocosmetic applications owing to its notable biological activities, including anti-inflammatory and anti-aging effects. Conventional production, however, relies on environmentally unfriendly chemical synthesis or limited natural extraction with low yield and high cost.

To address these challenges, we developed a biosynthetic system in engineered Komagataella pastoris. By co-expressing high-performance xylanase and Pro-Xylane synthase, our chassis enables direct, value-added conversion of xylan into Pro-Xylane. The system features a smart xylose-inducible module that dynamically regulates a modular enzymatic cascade through tailored metabolic pathways. Integrating synthetic genetic circuits with native pentose metabolism and applying modular control strategies, we established an efficient, sustainable, and tunable production system. This approach highlights the power of synthetic biology–driven cell machines for high-value biotransformations and provides a proof-of-concept platform for the programmable biosynthesis of Pro-Xylane.