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New Red-Emitting Chloride-Sensitive Fluorescent Protein with Biological Uses.

ABSTRACT: A new chloride-sensitive red fluorescent protein derived from Entacmaea quadricolor is described. We found that mBeRFP exhibited moderate sensitivity to chloride and, via site-directed mutagenesis (S94V and R205Y), we increased the chloride affinity by more than an order of magnitude (k_d = 106 ± 6 mM) at physiological pH. In addition, cis-trans isomerization of the chromophore produces a dual emission band with different chloride sensitivities, which allowed us to develop a ratiometric methodology to measure intracellular chloride concentrations.

SUBMITTER: Salto R

PROVIDER: S-EPMC8478333 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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New Red-Emitting Chloride-Sensitive Fluorescent Protein with Biological Uses.

Salto Rafael R Giron Maria D MD Puente-Muñoz Virginia V Vilchez Jose D JD Espinar-Barranco Laura L Valverde-Pozo Javier J Arosio Daniele D Paredes Jose M JM

ACS sensors 20210620 7

A new chloride-sensitive red fluorescent protein derived from Entacmaea quadricolor is described. We found that mBeRFP exhibited moderate sensitivity to chloride and, via site-directed mutagenesis (S94V and R205Y), we increased the chloride affinity by more than an order of magnitude (kd = 106 ± 6 mM) at physiological pH. In addition, cis-trans isomerization of the chromophore produces a dual emission band with different chloride sensitivities, which allowed us to ...[more]

PMID: 34148347

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