The existence of a purine nucleotide binding site on brown fat mitochondria

The existence of a purine nucleotide binding site on brown fat mitochondria 

Since it was shown by Cannon et al. [23] that ADP acted from the outside of the mitochondria to induce respiratory control, a specific site of interaction could be envisaged. Such a site was characterized by Nicholls [33] by binding of [ H]GDP. Further, by labelling brown fat mitochondria with [ P]azido-ATP, Heaton et al. [34] demonstrated that — besides the ATP/ADP-translocase at 30 kDa — a specific band with a molecular weight of 32000 was labelled, and this was identical with the GDP-binding site. This protein (i.e., thermogenin) had already been observed by Ricquier and Kader as the only protein the concentration of which was markedly altered in brown fat mitochondria isolated from cold-acclimated animals [35] (Fig. 10.8). 

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