Structural Perturbation of Superfolder GFP in the Presence of Guanidine Thiocyanate

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Abstract

The guanidine-thiocyanate-induced denaturation-renaturation of sfGFP was studied. It was shown that the disruption of sfGFP native structure occurs in the range of guanidine thiocyanate concentrations from 0.5 to 2.5 M. This process was accompanied by simultaneous changes of all recorded parameters. It was found that the small guanidine thiocyanate concentrations (less then 0.1-0.2 M) triggered local structural disturbances in protein which result in significant decrease of chromophore and tryptophan fluorescence intensity and change of protein visible absorption spectrum.

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Circular permutation and receptor insertion within green fluorescent proteins.

G S Baird, D Zacharias, R Tsien (1999)

Many areas of biology and biotechnology have been revolutionized by the ability to label proteins genetically by fusion to the Aequorea green fluorescent protein (GFP). In previous fusions, the GFP has been treated as an indivisible entity, usually appended to the amino or carboxyl terminus of the host protein, occasionally inserted within the host sequence. The tightly interwoven, three-dimensional structure and intricate posttranslational self-modification required for chromophore formation would suggest that major rearrangements or insertions within GFP would prevent fluorescence. However, we now show that several rearrangements of GFPs, in which the amino and carboxyl portions are interchanged and rejoined with a short spacer connecting the original termini, still become fluorescent. These circular permutations have altered pKa values and orientations of the chromophore with respect to a fusion partner. Furthermore, certain locations within GFP tolerate insertion of entire proteins, and conformational changes in the insert can have profound effects on the fluorescence. For example, insertions of calmodulin or a zinc finger domain in place of Tyr-145 of a yellow mutant (enhanced yellow fluorescent protein) of GFP result in indicator proteins whose fluorescence can be enhanced severalfold upon metal binding. The calmodulin graft into enhanced yellow fluorescent protein can monitor cytosolic Ca(2+) in single mammalian cells. The tolerance of GFPs for circular permutations and insertions shows the folding process is surprisingly robust and offers a new strategy for creating genetically encodable, physiological indicators.

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The fluorescent protein palette: tools for cellular imaging.

Richard Day, Michael W. Davidson (2009)

This critical review provides an overview of the continually expanding family of fluorescent proteins (FPs) that have become essential tools for studies of cell biology and physiology. Here, we describe the characteristics of the genetically encoded fluorescent markers that now span the visible spectrum from deep blue to deep red. We identify some of the novel FPs that have unusual characteristics that make them useful reporters of the dynamic behaviors of proteins inside cells, and describe how many different optical methods can be combined with the FPs to provide quantitative measurements in living systems (227 references).

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Genetically encoded biosensors based on engineered fluorescent proteins.

Wolf B. Frommer, Jane W. Davidson, Robert Campbell (2009)

Fluorescent proteins have revolutionized cell biology by allowing researchers to non-invasively peer into the inner workings of cells and organisms. While the most common applications of fluorescent proteins are to image expression, localization, and dynamics of protein chimeras, there is a growing interest in using fluorescent proteins to create biosensors for minimally invasive imaging of concentrations of ions and small molecules, the activity of enzymes, and changes in the conformation of proteins in living cells. This tutorial review provides an overview of the progress made in the development of fluorescent protein-based biosensors to date.