Changes of the aerobic and anaerobic energy metabolism during the early post-mortem meat formation in the pig with special reference to mitochondrial F0F1-ATPase and the phenomenon of cellular (mitochondrial) treason

• Applicants: Professorin Corinna Kehrenberg, Ph.D.; Privatdozent Dr. Carsten Krischek, since 11/2015
• Subject Area: Animal Breeding, Animal Nutrition, Animal Husbandry
• Term: from 2013 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 230879306

After slaughter of pigs, muscles with higher proportions of oxidative fibers (red muscles) in comparison to those with lower proportions (white muscles) have higher final pH values. However, the pH reduction curve is not different in most cases between these muscle types. This discrepancy may be due to the higher buffer capacity of white muscles and/ or the accelerated pH reduction in red fibers due to the phenomenon of cellular (mitochondrial) treason. This phenomenon is related to a functional change of the enzyme F0F1-ATPase. Under physiological conditions, the electrochemical proton gradient across the inner mitochondrial membrane is associated with the synthesis of ATP, catalyzed by the F0F1-ATPase. Oxygen deficiency (hypoxia, e.g. after slaughter) reduces the proton gradient. For maintenance of the gradient F0F1-ATPase can change to an ATP-dependent proton pump, associated with increased ATP consumption of the tissue (treason). Since at this time due to hypoxia ATP is formed by anaerobic glycolysis accompanied with lactate accumulation, it could be assumed that the pH is accelerated to the level of the white muscles. Data about cellular (mitochondrial) treason in skeletal muscles in pigs have not been published. Therefore, in the present study changes of mitochondrial respiratory capacity, of enzymes from the energy metabolism, particularly of the F0F1-ATPase, of nucleotides and of the buffer capacity during normoxia and hypoxia after slaughter of pigs should be studied biochemically and molecular biologically. At the same time muscles will be characterized in terms of different meat quality parameters (e.g., pH, drip loss) and analyzed in conjunction with the biochemical and molecular biological results. The aim of the study is to investigate the influence of mitochondria on meat formation shortly after slaughter (early post-mortem) at the transition between the normal atmospheric oxygen concentration (normoxia) and hypoxia / anoxia of the muscle tissue, with special focus on the F0F1-ATPase.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Professor Dr. Michael Wicke, until 11/2015 (†)