20 research outputs found
Dark States in Ionic Oligothiophene Bioprobes—Evidence from Fluorescence Correlation Spectroscopy and Dynamic Light Scattering
Filamentous fungi in microtiter plates—an easy way to optimize itaconic acid production with Aspergillus terreus
A closer look at Aspergillus: online monitoring via scattered light enables reproducible phenotyping
Production of itaconate by whole-cell bioconversion of citrate mediated by expression of multiple cis-aconitate decarboxylase (cadA) genes in Escherichia coli
Carbohydrate to Itaconic Acid Conversion by Aspergillus terreus and the Evaluation of Process Monitoring Based on the Measurement of CO2
Forster Resonance Energy Transfer beyond 10 nm : Exploiting the Triplet State Kinetics of Organic Fluorophores
Inter- or intramolecular distances of biomolecules can be studied by Forster resonance energy transfer (FRET). For most FRET methods, the observable range of distances is limited to 1-10 nm, and the labeling efficiency has to be controlled carefully to obtain accurate distance determinations, especially for intensity-based methods. In this study, we exploit the triplet state of the acceptor fluorophore as a FRET readout using fluorescence correlation spectroscopy and transient state monitoring. The influence of donor fluorescence leaking into the acceptor channel is minimized by a novel suppression algorithm for spectral bleed-through, thereby tolerating a high excess (up to 100-fold) of donor-only labeled samples. The suppression algorithm and the high sensitivity of the triplet state to small changes in the fluorophore excitation rate make it possible to extend the observable range of FRET efficiencies by up to 50% in the presence of large donor-only populations. Given this increased range of FRET efficiencies, its compatibility with organic fluorophores, and the low requirements on the labeling efficiency and instrumentation, we foresee that this approach will be attractive for in vitro and in vivo FRET-based spectroscopy and imaging.QC 20150624</p