The 16th Femtochemistry Conference (FEMTO16)

Session

Session 8 - Biosystems II

8

Jun 24, 2025, 4:25 PM

Savoia Hotel, Trieste, Italy

42. Mechanism in Reversibly Switchable Fluorescent Proteins

Steve Meech (University of East Anglia)

6/24/25, 4:25 PM

Invited talk

Reversibly switchable fluorescent proteins (FPs) are critical to superesolution bioimaging. The widely used negative switching FPs are well characterized. The under-used positive and decoupled switching FPs much less so. Here we report complementary ultrafast transient optical and infra-red absorption measurements of photoswitching in Padron, Kohinoor (+FPs) and Dreiklag (dcFP). The two...

176. Multi-step 11-cis to all-trans retinal photoisomerization in bestrhodopsin, an unusual microbial rhodopsin

John T.M. Kennis (Vrije Universiteit Amsterdam)

6/24/25, 4:55 PM

Contributed talk

Rhodopsins constitute a broad class of sensory photoreceptors with retinal chromophores bound to the protein via a retinal Schiff base (RSB). Microbial rhodopsins are mostly activated through an all-trans to 13-cis photoisomerization reaction, whereas animal rhodopsins are invariably activated through an 11-cis to all-trans isomerization reaction. The recently discovered bestrhodopsins...

177. Novel femtosecond photoreactions in flavo-enzymes

Marten Vos (Ecole Polytechnique)

6/24/25, 5:15 PM

Contributed talk

In exceptional cases, flavo-enzymes perform functional light-driven catalysis, such as in fatty acid photodecarboxylase (FAP) [1]. Yet most display light-independent functions, although in these photophysical processes also occur. Such processes can have photoprotective functions, and may also be exploited for photocatalysis or photoswitching applications [2]. This contribution highlights...

171. Optical coherent control of biological electron transfer

Dongping Zhong (Shanghai Jiao Tong University)

6/24/25, 5:35 PM

Contributed talk

Optical control of dynamic processes has been challenging yet has been demonstrated in several chemical and biological systems. The control of a reaction passing the widely present conical intersection has not been realized. Here, we can modulate the phase of the excitation pulse to achieve control of an important chemical process, the dynamics of β-carotene to access the conical intersection...

242. Excitation dynamics in DNA-templated silver nanoclusters

Donatas Zigmantas (Chemical Physics, Lund University)

6/24/25, 5:55 PM

Contributed talk

DNA-templated silver nanoclusters have fascinating properties, including high absorption cross section and high fluorescence quantum yield. Importantly, these and other features can be readily tuned by changing the DNA sequence of strands, which stabilize the silver cluster inside. The combination of desirable properties and tunability makes them potentially suitable for a wide range of...