Characterisation of oxidative phosphorylation in skeletal muscle mitochondria subpopulations in pig: a study using top‐down elasticity analysis

FEBS Letters

Herpin, Patrick²  Vincent, Annie²  Goglia, Fernando¹  Damon, Marie²  Lombardi, Assunta³ 

[1] Facoltà di Scienze, Università degli Studi del Sannio, Via Port’ Arsa, 82100 Benevento, Italy;INRA, Unité Mixte de Recherches sur le Veau et le Porc, 35590 Saint-Gilles, France;Dipartimento di Fisiologia Generale ed Ambientale, Università degli Studi di Napoli ‘Federico II’, Via Mezzocannone 8, 80134 Naples, Italy

关键词: Skeletal muscle mitochondrion;    Top-down elasticity analysis;    Oxidative phosphorylation;    Respiratory chain;    SS;    subsarcolemmal mitochondria;    IMF;    intermyofibrillar mitochondria;    RCR;    respiratory control ratio;    COX;    cytochrome oxidase;    ΔΨ;    membrane potential;    Ph3MeP+;    triphenylmethylphosphonium;   

DOI  :  10.1016/S0014-5793(00)01633-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

In skeletal muscle, two mitochondrial populations are present which, on the basis of their localisation, are termed intermyofibrillar and subsarcolemmal mitochondria (IMF and SS, respectively). These two populations have different biochemical characteristics and show different responses to physiological stimuli. In this paper, we characterise the oxidative phosphorylation of SS and IMF using ‘top-down’ elasticity analysis. We excluded the possibility that their different characteristics can be attributed to a different degree of breakage of the two types of mitochondria due to the different isolation procedures used in their preparation. The higher respiration rate and higher respiratory control ratio shown by IMF compared with those shown by SS are principally due to the higher activities of the reactions involved in substrate oxidation as confirmed by the measurement of cytochrome oxidase activity. There is no difference in the leak of protons across the inner mitochondrial membrane between IMF and SS; a faster rate of ATP synthesis and turnover is driven by the lower membrane potential in SS compared with in IMF.

【 授权许可】

Unknown