HALOGEN · HALOgenase-driven high-throughput experimentation and GENome mining

Halogenation is a key transformation in organic chemistry, widely used to enhance molecular properties and reactivity. Organohalides play critical roles in pharmaceuticals, agrochemicals, and materials, serving both as bioactive compounds and versatile intermediates in synthetic chemistry. Traditional halogenation methods rely on hazardous reagents and harsh conditions, raising sustainability and selectivity concerns. In contrast, halogenases enable site-selective halogenation under mild, aqueous conditions, evidenced by over 8,000 known halogenated natural products. Despite enormous potential, their application in chemoenzymatic synthesis remains limited due to narrow substrate scopes, a lack of diverse, well-characterized enzymes, and the absence of approachable platforms.The HALOGEN project (HALOgenase-driven high-throughput experimentation and GENome mining) aims to unlock the potential of halogenases for sustainable synthesis through the development of a high-throughput, microfluidic experimentation platform for compound diversification. RO1 focuses on building a chemoenzymatic workflow that integrates biocatalytic halogenation (RO1a) with downstream abiotic catalysis (RO1b) to diversify small-molecule libraries, including natural products. Using flow-based microfluidic chips coupled with mass spectrometry, we will enable multiplexed screening of enzyme–substrate combinations under precise, scalable conditions. RO2 focuses on expanding the enzymatic toolbox by genome mining marine cyanobacteria to uncover novel halogenases (RO2a) and structurally unique halogenated natural products (RO2b), including those derived from cryptic halogenation pathways.Together, this work will expand the enzymatic halogenation toolbox, provide fundamental insight into halogenase reactivity, and establish a broadly applicable platform for eco-friendly late-stage functionalization of small molecule libraries for medicinal chemistry.