Li, X.; Li, Z.; Zhao, M. Illuminating Histidine-Deficient Intracellular Environments: A Novel Whole-Cell Microbial Fluorescence Sensor. Chemosensors2023, 11, 515.
Li, X.; Li, Z.; Zhao, M. Illuminating Histidine-Deficient Intracellular Environments: A Novel Whole-Cell Microbial Fluorescence Sensor. Chemosensors 2023, 11, 515.
Li, X.; Li, Z.; Zhao, M. Illuminating Histidine-Deficient Intracellular Environments: A Novel Whole-Cell Microbial Fluorescence Sensor. Chemosensors2023, 11, 515.
Li, X.; Li, Z.; Zhao, M. Illuminating Histidine-Deficient Intracellular Environments: A Novel Whole-Cell Microbial Fluorescence Sensor. Chemosensors 2023, 11, 515.
Abstract
Histidine is an essential amino acid with significant implications in human growth and neuromodulation. Its concentration within cells, when either elevated or reduced, can indicate different diseases. While various methods exist to measure increased histidine levels, there remains a significant lack of sensors capable of actively responding to histidine deficiency within cells and releasing strong signals. In this study, we exploited the high induction levels of the his operon in S. Typhimurium SL1344, a histidine auxotroph, within a histidine-deficient environment, to develop a specific bacterial sensor with sensitivity towards low histidine concentrations. The SL1344-pGEX sensor, with a high copy number, exhibited remarkable sensitivity and selectivity to histidine in the range of 0 to 50 μM. Notably, even a minute addition of histidine (approximately 2.5 μM) to the M9 medium led to observable fluorescence reduction, rendering it highly suitable for monitoring histidine-deficient cellular environments. This bacterial fluorescence sensor holds great potential for detecting changes in intracellular histidine concentrations during pathogenic bacterial infections and for assessing the impact of drugs on cellular metabolism.
Keywords
histidine; microbial fluorescence sensor; S. Typhimurium SL1344; live cell imaging; histidine deficiency
Subject
Chemistry and Materials Science, Analytical Chemistry
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
