A fast, visible-light-sensitive azobenzene for bioorthogonal ligation

Area of Science:

• Chemical Biology
• Photochemistry
• Biomolecular Engineering

Background:

• Azobenzenes are photoresponsive molecules used to control biological processes.
• Key challenges include site-selective incorporation into biomolecules and using visible light for photoisomerization.

Purpose of the Study:

• To develop a novel push-pull azobenzene for controlled biological applications.
• To enable site-selective incorporation and visible-light-triggered photoisomerization.

Main Methods:

• Utilized Staudinger-Bertozzi ligation for azide group conjugation.
• Employed visible light (>440 nm) for photoisomerization.
• Investigated thermal relaxation in aqueous solutions.

Main Results:

• Developed a push-pull azobenzene with efficient Staudinger-Bertozzi ligation.
• Demonstrated visible-light addressability and typical push-pull system properties (solvato- and acidochromism).
• Observed low-millisecond thermal relaxation in water, suitable for biological timescales.

Conclusions:

• The novel azobenzene allows for precise, visible-light-controlled modification of biomolecules.
• Successful incorporation into a quartz surface and a functional peptide (Sp1 zinc finger) was achieved.
• This approach offers a new tool for photo-controlled biological applications.