A Twisted Chromophore that Powers a Fluorescent Protein Chloride Sensor

24 July 2024, Version 1
This content is a preprint and has not undergone peer review at the time of posting.

Abstract

Chromophore nonplanarity and flexibility have long been argued to govern the fluorescence efficiency of fluorescent proteins (FPs), yet their relative importance has been elusive. Herein, we tackle this question by investigating two FP-based chloride (Cl–) sensors, ChlorON1 and 3, using ultrafast spectroscopy and theoretical calculations. We find that fluorescence enhancement of the chloride-bound ChlorON3 stems from a more twisted chromophore than ChlorON1. This counterintuitive finding indicates that chromophore planarity is not, but conformational rigidity is, the decisive factor for high fluorescence efficiency.

Keywords

fluorescent protein based biosensors
excited state processes
fluorescence turn-on properties
ultrafast spectroscopy
femtosecond stimulated Raman
chloride sensing mechanism
chromophore nonplanarity and flexibility

Supplementary materials

Title
Description
Actions
Title
Supporting Information
Description
Supporting Information (SI) in a single PDF file with TOC pages, text (Experimental and Methods, Supplementary Discussions), 23 high-resolution figures, four tables, and references.
Actions

Comments

Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.
Comment number 1, This comment has been removed by the moderator.: Jul 25, 2024, 23:45
This comment has been removed by the moderator.