The effect of temperature on the activity of μ- and m-calpain and calpastatin during post-mortem storage of porcine longissimus muscle.
The experiment was conducted to determine the effect of temperature during post-mortem muscle storage on the activity of the calpain system, the myofibril fragmentation and the free calcium concentration. Porcine longissimus muscle were incubated from 2h post-mortem at temperatures of 2, 15, 25 and 30 °C and sampling times were at 2, 6, 24, 48 and 120 h post-mortem. After 120 h at 30 °C the free calcium concentration increased to 530 μM from 440 μM at 2 °C. Incubation at temperatures higher than 2 °C resulted in the appearance of autolyzed m-calpain activity and a decrease of native m-calpain activity. Native m-calpain decreased more slowly than native μ-calpain, and the autolysis process started later. Myofibril fragmentation increased with storage time and incubation temperature, while calpastatin activity decreased. The study showed that high temperature incubation not only rapidly activated μ-calpain but at higher temperatures and later time points also m-calpain.
Department of Food Science, Faculty of Life Sciences, University of Copenhagen, Rolighedsvej 30, DK-1958 Frederiksberg C, Denmark.
Luigi
L
Pomponio
Per
P
Ertbjerg
D000818:Animals; D001329:Autolysis / Q000517:prevention & control; D002118:Calcium / Q000032:analysis; D002135:Calcium-Binding Proteins / Q000302:isolation & purification / Q000494:pharmacology*; D002154:Calpain / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D015853:Cysteine Proteinase Inhibitors / Q000302:isolation & purification / Q000494:pharmacology*; D005511:Food Handling; D008460:Meat / Q000032:analysis*; D018482:Muscle, Skeletal / Q000737:chemistry / Q000187:drug effects / Q000201:enzymology*; D009210:Myofibrils / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D010316:Particle Size; D059748:Proteolysis / Q000187:drug effects; D012518:Sarcomeres / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D034421:Sus scrofa; D013696:Temperature; D013997:Time Factors
D002135:Calcium-Binding Proteins; D015853:Cysteine Proteinase Inhibitors; C033668:calpastatin; D002154:Calpain; C449000:m-calpain; C449002:mu-calpain; D002118:Calcium