Real-Time Optical Detection of Isoleucine in Living Cells through a Genetically-Encoded Nanosensor.

ABSTRACT: Isoleucine is one of the branched chain amino acids that plays a major role in the energy metabolism of human beings and animals. However, detailed investigation of specific receptors for isoleucine has not been carried out because of the non-availability of a tool that can monitor the metabolic flux of this amino acid in live cells. This study presents a novel genetically-encoded nanosensor for real-time monitoring of isoleucine in living cells. This nanosensor was developed by sandwiching a periplasmic binding protein (LivJ) of E. coli between a fluorescent protein pair, ECFP (Enhanced Cyan Fluorescent Protein), and Venus. The sensor, named GEII (Genetically Encoded Isoleucine Indicator), was pH stable, isoleucine-specific, and had a binding affinity (K_d) of 63 ± 6 μM.

SUBMITTER: Singh S 

PROVIDER: S-EPMC6983066 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature