title: Partial autolysis of μ/m-calpain during post mortem aging of chicken muscle.
abstract: The objective of this study was to investigate changes occurring in μ/m-calpain in post mortem chicken muscles and to determine the origin of the unknown bands found in calpain casein zymography. The unknown bands were reported with slightly greater mobility compared to conventional μ/m-calpain bands in casein zymography. Identification of these bands was accomplished using native polyacrylamide gel electrophoresis, liquid chromatography tandem mass spectrometry and with protein phosphatase treatment. Results showed that the unknown bands were corresponding to μ/m-calpain, and dephosphorylation by protein phosphatase did not change their appearance. The calpain samples were then incubated with various concentrations of Ca2+to determine the relationship between changes in μ/m-calpain and the appearance of the unknown bands. The products of μ/m-calpain partial autolysis were found to be consistent with the appearance of the unknown bands. Therefore, the appearance of these bands did not result from phosphorylation of μ/m-calpain as previously hypothesized, but from partial autolysis of μ/m-calpain. Also their presence suggests that μ/m-calpain undergoes partial autolysis during aging which may play certain roles in meat quality improvement.
authors.affiliation: Nanjing Innovation Center of Meat Products Processing, Synergetic Innovation Center of Food Safety and Nutrition, Nanjing Agricultural University, Nanjing, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Nanjing Innovation Center of Meat Products Processing, Synergetic Innovation Center of Food Safety and Nutrition, Nanjing Agricultural University, Nanjing, China.
authors.forename: Nanqi
authors.initials: N
authors.lastname: Jiang
authors.affiliation: Nanjing Innovation Center of Meat Products Processing, Synergetic Innovation Center of Food Safety and Nutrition, Nanjing Agricultural University, Nanjing, China.
authors.forename: Miaozhen
authors.initials: M
authors.lastname: Li
authors.affiliation: Nanjing Innovation Center of Meat Products Processing, Synergetic Innovation Center of Food Safety and Nutrition, Nanjing Agricultural University, Nanjing, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Huang
authors.affiliation: Nanjing Innovation Center of Meat Products Processing, Synergetic Innovation Center of Food Safety and Nutrition, Nanjing Agricultural University, Nanjing, China.
authors.forename: Guanghong
authors.initials: G
authors.lastname: Zhou
mesh_terms: D000818:Animals; D001329:Autolysis; D002118:Calcium; D002154:Calpain / Q000302:isolation & purification / Q000378:metabolism*; D002364:Caseins; D002645:Chickens; D002853:Chromatography, Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D063427:Food Quality; D061353:Food Storage; D008460:Meat / Q000032:analysis; D010749:Phosphoprotein Phosphatases; D011180:Postmortem Changes; D053719:Tandem Mass Spectrometry
chemical_list: D002364:Caseins; D010749:Phosphoprotein Phosphatases; D002154:Calpain; C449002:mu-calpain; D002118:Calcium
keywords: aging; autolysis; chicken; phosphorylation; μ/m-calpain