The protection of bovine skeletal myofibrils from proteolytic damage post mortem by small heat shock proteins.
This study aimed to determine how small heat shock proteins (sHSPs) protect myofibrillar proteins from μ-calpain degradation during ageing. Immunoprecipitation experiments with M. longissimus dorsi (LD) from Angus heifers (n = 14) examined the interaction between αβ-crystallin, desmin, titin, HSP20, HSP27 and μ-calpain. Results showed that αβ-crystallin associated with desmin, titin, HSP20, HSP27 and μ-calpain. Exogenous αβ-crystallin reduced desmin and titin degradations in myofibrillar extracts and attenuated μ-calpain activity. In a second experiment, bull LD (n = 94) were aged at -1.5°C for up to 28 days post mortem. μ-Calpain autolysed faster in high ultimate pH (pH(u)) meat (pH(u)≥6.2) and this was concomitant with the more rapid degradation of titin and filamin in this pH(u) group. Desmin stability in intermediate pH(u) meat (pH(u) 5.8 to 6.19) may be due to the protection of myofibril-bound sHSPs combined with the competitive inhibition of μ-calpain by sHSPs.
Meat Science and Technology, AgResearch Limited., Ruakura Research Centre, Private Bag 3123, Hamilton, New Zealand.
D
D
Lomiwes
Plant and Food Research, Food Industry Science Centre, Private Bag 11600, Palmerston North, New Zealand.
S M
SM
Hurst
Meat Science and Technology, AgResearch Limited., Ruakura Research Centre, Private Bag 3123, Hamilton, New Zealand.
P
P
Dobbie
Meat Science and Technology, AgResearch Limited., Ruakura Research Centre, Private Bag 3123, Hamilton, New Zealand.
D A
DA
Frost
Plant and Food Research, Food Industry Science Centre, Private Bag 11600, Palmerston North, New Zealand.
R D
RD
Hurst
School of Applied Sciences, AUT University, Private Bag 92006, Auckland, New Zealand.
O A
OA
Young
Meat Science and Technology, AgResearch Limited., Ruakura Research Centre, Private Bag 3123, Hamilton, New Zealand. Electronic address: mustafa.farouk@agresearch.co.nz.
M M
MM
Farouk
D000818:Animals; D001329:Autolysis; D001947:Breeding; D002154:Calpain / Q000378:metabolism*; D002417:Cattle; D064211:Connectin / Q000378:metabolism; D003459:Crystallins / Q000378:metabolism; D003893:Desmin / Q000378:metabolism; D005260:Female; D064448:Filamins / Q000378:metabolism; D050886:HSP20 Heat-Shock Proteins / Q000378:metabolism; D055551:HSP27 Heat-Shock Proteins / Q000378:metabolism; D050888:Heat-Shock Proteins, Small / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008297:Male; D008460:Meat / Q000032:analysis*; D009124:Muscle Proteins / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism*; D009210:Myofibrils / Q000378:metabolism*; D011180:Postmortem Changes; D059748:Proteolysis
D064211:Connectin; D003459:Crystallins; D003893:Desmin; D064448:Filamins; D050886:HSP20 Heat-Shock Proteins; D055551:HSP27 Heat-Shock Proteins; D050888:Heat-Shock Proteins, Small; D009124:Muscle Proteins; D002154:Calpain; C449002:mu-calpain
Beef; Desmin; Small heat shock proteins; Tenderness; αβ-Crystallin; μ-Calpain