Applications of Time-Resolved RET

Kgure 14.3S. Sdiematic (fia un of d(Kdde.stnuide(i DMA with ler bium telaie (dcmw) at one S end and TMR (acceptor) at odier S -end. The len of DNA was a lO-ma. Revised ftiin Ref. fiOL 

Tbe use of lanthanide donors has a nun o- of advantages, one of which is their symmetrical structure. Die emission from landianides is unpolarized, and, as a result, the orientation factor can only be important for the acceptor. Diis limits the range of possible values to  

In this ch ter we have attempted to show die potential of time-resolved measurements for determination of the solution conformations of macromolecules. The determination of Conformational distributions appears to be a rather unique property of the time-resolved measurements. Most physical methods reveal only an average conformation. Additionally, the data contain information on the timescale of conformational changes. With the introduction of long-lived probes, conformational dynamics will be measurable on timescales from nanoseconds to tens of microseconds. 

As a final comment, we want to emphasize that all the results described in this chapter were for covalently linl donor-acceptor pairs, with a single acceptor per donor. I frerent and somewhat mtxe complex theory is needed to describe systems with multiple acceptors and unlmked K obes. Such syst ns occur commonly in menforanes and nucleic acids and are described in (he following chapt.  

Wilchek, M., Katriialsid-Katzir, E., and Sfeinberg, I. Z., 1975, Distribution of eod-io-eod distances of oligopeptides in solu- 

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