Item Type: | Article |
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Title: | Microinjected glutathione reductase crystals as indicators of the redox status in living cells |
Creators Name: | Keese, M.A., Saffrich, R., Dandekar, T., Becker, K. and Schirmer, R.H. |
Abstract: | The flavoenzyme glutathione reductase catalyses electron transfer reactions between two major intracellular redox buffers, namely the NADPH/NADP+ couple and the 2 glutathione/glutathione disulfide couple. On this account, microcrystals of the enzyme were tested as redox probes of intracellular compartments. For introducing protein crystals into human fibroblasts, different methods (microinjection, particle bombardment and optical tweezers) were explored and compared. When glutathione reductase crystals are present in a cytosolic environment, the transition of the yellow E(ox) form to the orange-red 2-electron reduced charge transfer form, EH(2), is observed. Taking into account the midpoint potential of the E(ox)/EH(2) couple, the redox potential of the cytosol was found to be <−270 mV at pH 7.4 and 37°C. As a general conclusion, competent proteins in crystalline – that is signal-amplifying – form are promising probes for studying intracellular events. |
Keywords: | Protein Crystal, Glutathione Reductase, Cytosol, Bilostic Crystal Transfer, Microinjection, Redox Potential |
Source: | FEBS Letters |
ISSN: | 0014-5793 |
Publisher: | Elsevier |
Volume: | 447 |
Number: | 2-3 |
Page Range: | 135-138 |
Date: | 26 March 1999 |
Official Publication: | https://doi.org/10.1016/S0014-5793(99)00296-3 |
PubMed: | View item in PubMed |
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