Magnesium Green

high-resolution terminology - matching measurements at high-resolution

Magnesium Green

Description

Magnesium Green belongs to the extrinsic fluorophores applied for measurement of mitochondrial ATP production with mitochondrial preparations. This fluorescent dye fluoresces when bound to Mg²⁺, and the technique to measure mitochondrial ATP production is based on the fact that Mg²⁺ present different dissociation constants for ADP and ATP, and ADP/ATP are exchanged by the adenine nucleotide translocase (ANT). » MiPNet article

Abbreviation: MgG

Reference: Chinopoulos 2014 Methods Enzymol

MitoPedia methods: Fluorometry 

Magnesium Green^TM is a registered trademark and available from Thermo Fisher Scientific (former: Invitrogen) in several formulations. For measuring mitochondrial ATP production a membrane impermeant formulation must be chosen (e.g. #M3733). Note that while its K_D for magnesium is 1.0 mM, its K_D for calcium is 6 µM: Magnesium Green binds stronger to calcium than to magnesium and cannot be used in the presence of significant concentrations of free calcium. Possible contaminations with transition metals should be complexed by a small (µM range) concentration of EDTA or DTPA.

• Instrument

» O2k-FluoRespirometer with Fluorescence-Sensor Blue/Filter Set MgG / CaG

• O2k-Manual

» A kinetic assay of mitochondrial ADP-ATP exchange rate mediated by the adenine nucleotide translocase by [Chinopoulos C]

» Manual Fluorescent Magnesium Indicators.

• Magnesium Green and Calcium Green share the same fluorophore moiety in their molecular structure. Therefore, the optical properties are very similar and the same fluorescence sensor and filter set can be used.

Signal and output

1. Signal: The O2k-Fluo LED2-Module is operated through the amperometric (Amp)-Channel of the O2k, with electric current (ampere [A]) as the primary signal.
2. Output: The focus of the output with Magnesium Green is on Type B: Flow, flux, rate.

K_d determination of ADP or ATP to Mg²⁺ using MgG

To assess the exchange of ADP/ATP by ANT using MgG, the K_d of ADP and ATP to Mg²⁺ should be previously calculated for the pertaining experimental conditions.