Accessing a Long‐Fluorescence‐Lifetime BODIPY Dye via Efficient Förster Resonance Energy Transfer Induced by Host‐Guest Doping

Posted on by
Accessing a Long-Fluorescence-Lifetime BODIPY Dye via Efficient Förster Resonance Energy Transfer Induced by Host-Guest Doping

Long-fluorescence lifetime: A novel pure organic RTP system with a long fluorescence lifetime has been achieved through an efficient FRET process via host-guest doping, offering great potential for information encryption, fingerprint identification, and bio-imaging applications.


Abstract

The development of pure organic room temperature phosphorescence (RTP) luminophores with high quantum yield and long emission lifetime has attracted considerable attention due to their extensive optoelectronic and biomedical applications. The commonly used BODIPY dyes have strong UV-Vis absorption, a relatively sharp emission peak, high quantum yield, and a short emission lifetime. By expending the molecular doping approach, we herein successfully achieved a long-fluorescence-lifetime BODIPY dye via efficient Förster resonance energy transfer (FRET) from RTP molecule o-AI-Cz to the short-lived fluorescence emitter Bodipy-2I. This host-guest material possessed an ultralong lifetime of up to 595 ms and a long emission wavelength under ambient conditions, which has great potential in data encryption and anti-counterfeiting applications. Moreover, this easily prepared FRET system exhibited an efficient response to two-photon excitation in living cell fluorescence imaging.

Nucleoside‐driven specificity of DNA Methyltransferase

Posted on by

We have studied adenosine binding specificities of two bacterial DNA methyltransferases Taq methyltransferase (M.TaqI), and HhaI methyltransferase (M.HhaI). While these DNA methyltransferases have similar cofactor binding pocket interactions, experimental data showed different specificity for novel cofactors ((SNM) (S-guanosyl-L-methionine (SGM), S-cytidyl-L-methionine (SCM), S-uridyl-L-methionine (SUM)).Protein dynamics corroborate the experimental data on the cofactor specificities. For M.TaqI the specificity for S-adenosyl-L-methionine (SAM) is governed by the tight binding on the nucleoside part of the cofactor, while for M.HhaI the degree of freedom of the nucleoside chain allows the acceptance of other bases. The experimental data proves a catalytically productive methylation by M.HhaI binding pocket for all the SNM (S-nucleobase-L-methionine). Our results suggest a new route for successful design of unnatural SNM analogues for methyltransferases as a tool for cofactor engineering.