The respiratory acceptor control ratio (RCR) is defined as State 3/State 4 . If State 3 is measured at saturating [ADP], RCR is the inverse of the OXPHOS control ratio, L/P (when State 3 is equivalent to the OXPHOS state, P). RCR is directly but non-linearly related to the OXPHOS coupling efficiency, j≈P = 1-L/P. Whereas the normalized flux ratio j≈P has boundaries from 0.0 to 1.0, RCR ranges from 1.0 to infinity, which needs to be considered when performing statistical analyses. In intact cells, the term RCR has been used for the ratio State 3u/State 4o, i.e. for the inverse L/E ratio [2,3]. Then for conceptual and statistical reasons, RCR should be replaced by the ET-coupling efficiency, j≈E= 1-L/E .
MitoPedia concepts: Respiratory control ratio
MitoPedia methods: Respirometry
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