Comparison List


a.k.a. cpEYFP

cpEYFP(V68L/Q69K) is a basic (constitutively fluorescent) green/yellow fluorescent protein published in 2001.
Oligomerization Organism Molecular Weight Cofactor
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FPbase ID: 2TAPF


Ex λ Em λ EC (M-1 cm-1) QY Brightness pKa Maturation (min) Lifetime (ns)
506 520          


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cpEYFP(V68L/Q69K) Sequence

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A YFP variant, EYFP(V68L/Q69K) was subjected to circular permutation. The original N and C termini were linked through a pentapeptide linker GGSGG, rendering Y145 and N144 new N and C termini, respectively. The blue-shift in the absorbance suggests that the chromophore was protonated in cpEYFP(V68L/Q69K). The excitation spectrum has two peaks at 417 and 506 nm which is reminiscent of the bimodal excitation spectrum of WT-GFP. The protonated species of cpEYFP(V68L/Q69K) absorbs around 420 nm fluoresced, whereas protonated species of most YFPs do not.

Nagai et al. (2001)

Primary Reference

Circularly permuted green fluorescent proteins engineered to sense Ca2+

Nagai T, Sawano A, Park Es, Miyawaki A

(2001). Proceedings of the National Academy of Sciences, 98(6) , 3197-3202. doi: 10.1073/pnas.051636098. Article   Pubmed

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