title: A native-chemical-ligation-mechanism-based ratiometric fluorescent probe for aminothiols.
abstract: Thiol-containing amino acids (aminothiols) such as cysteine (Cys) and homocysteine (Hcy) play a key role in various biological processes including maintaining the homeostasis of biological thiols. However, abnormal levels of aminothiols are associated with a variety of diseases. The native chemical ligation (NCL) reaction has attracted great attention in the fields of chemistry and biology. NCL of peptide segments involves cascade reactions between a peptide-α-thioester and an N-terminal cysteine peptide. In this work, we employed the NCL reaction mechanism to formulate a Förster resonance energy transfer (FRET) strategy for the design of ratiometric fluorescent probes that were selective toward aminothiols. On the basis of this new strategy, the ratiometric fluorescent probe 1 for aminothiols was judiciously designed. The new probe is highly selective toward aminothiols over other thiols and exhibits a very large variation (up to 160-fold) in its fluorescence ratio (I(458)/I(603)). The new fluorescent probe is capable of ratiometric detection of aminothiols in newborn calf and human serum samples and is also suitable for ratiometric fluorescent imaging of aminothiols in living cells.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan 410082, PR China.
authors.forename: Lin
authors.initials: L
authors.lastname: Yuan
authors.forename: Weiying
authors.initials: W
authors.lastname: Lin
authors.forename: Yinan
authors.initials: Y
authors.lastname: Xie
authors.forename: Sasa
authors.initials: S
authors.lastname: Zhu
authors.forename: Sheng
authors.initials: S
authors.lastname: Zhao
mesh_terms: D000818:Animals; D002417:Cattle; D003545:Cysteine / Q000032:analysis* / Q000097:blood; D031541:Fluorescence Resonance Energy Transfer; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry*; D056945:Hep G2 Cells; D006710:Homocysteine / Q000032:analysis* / Q000097:blood; D006801:Humans; D018613:Microscopy, Confocal
chemical_list: D005456:Fluorescent Dyes; D006710:Homocysteine; D003545:Cysteine