Frex and FrexH

Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, School of Pharmacy, East China University of Science and Technology, Shanghai, China.
Bioengineered bugs 05/2012; 3(3):181-8. DOI: 10.4161/bbug.19769
Source: PubMed


Reduced nicotinamide adenine dinucleotide (NADH) and its oxidized form play central roles in energy and redox metabolisms. For many years, researchers have relied on the weak NADH endogenous fluorescence signal to determine the NADH level in living cells. We recently reported a series of genetically encoded fluorescent sensors highly specific for NADH. These sensors allow real-time, quantitative measurement of this significant molecule in different subcellular compartments. In this study, we provide a more detailed discussion of the benefits and limitations of these genetically encoded fluorescent sensors. These sensors are utilized in most laboratories without the need for sophisticated instruments because of their superior sensitivity and specificity. They are also viable alternatives to existing techniques for measuring the endogenous fluorescence of intracellular NAD(P)H.

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Available from: Yuzheng Zhao, May 10, 2014
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    • ", 2000 ) . of the total mitochondrial NADH in resting cells . According to these calcu - lations , Frex sensors are unlikely to have a major impact on the total NADH concentration and the metabolic status of the cells in which they are expressed ( Zhao & Yang , 2012 ) . "
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