Effects Of L-lysine And L-histidine On Phosphorylation Of Post-mortem Chicken Proteins

Protein phosphorylation changed the structure of the protein,which in turn caused changes in protein function.In order to investigate the effects of NaCl,L-lysine(L-Lys),and L-histidine(L-His)on the changes of protein phosphorylation during the post-salinization of chicken meat,three-month-old yellow feather Broilers were used as experimental materials.Different post-mortem time and storage temperature conditions were selected to study the optimal storage temperature conditions and post-mortem time for protein phosphorylation to occur;chicken leg meat and chicken breasts that were matured for 90 minutes after mortem were selected at 4?.After adding L-Lys and L-His under high salt(3%NaCl)and low salt(1%NaCl)conditions,myofibrillar proteins were extracted,followed by SDS-PAGE electrophoresis,and then identified by fluorescence staining and liquid chromatography-tandem mass spectrometry.Identification of differentially phosphorylated proteins;labeling and enrichment of peptides of sample proteins using isotope TMT-labeled phosphorylated peptide enrichment technology,and systematic biological analysis revealed that L-Lys,L-His mechanisms of post-chicken proteins phosphorylation.1.The effect of post-mortem time and temperature on energy metabolism and pH during chicken rigidity.After the yellow feather broiler was slaughtered,the chicken breast(typical white muscle)and chicken leg(typical red muscle)were peeled and tested.The energy substance was stored at 25? and 4? for 0min,30min,60min,90min,120min,and 240min.With the determination of pH.The results showed that the changes in energy content and pH of different types of breast meat and leg meat were more stable at 4? than at 25?.The changes were greater in the first 90 minutes after slaughter,and then the trend tended to be gentle,indicating that the physiology of meat during this time The biochemical reaction is fierce,and the acid removal process is completed.4? and 25? can ensure that there is an energy substance for the phosphorylation experiment in the pickling process.Therefore,it was chosen to use breast and leg at 4? after slaughtering for 90 minutes acid discharge to carry out subsequent protein phosphorylation experiments.2.Effects of L-lysine and L-histidine on protein phosphorylation of post-mortem chicken breast and leg.Chicken breast and legs were marinated with NaCl and L-Lys,L-His for 16h,and then myofibrillar protein and sarcoplasmic protein were extracted and subjected to SDS-PAGE electrophoresis and identified by fluorescence staining and liquid chromatography-tandem mass spectrometry.There were significant differences in the level of protein phosphorylation between treatment groups(P<0.05).Most of the phosphorylated differential proteins identified in this experiment were related to sarcomere function,sugar metabolism,and ATPase activity,and the phosphorylation level was identified to be high The main proteins include ?-actinin-2,myosin heavy chain,?-enolase,sarcoplasmic/endoplasmic reticulum ATPase 1,etc.,and studies have shown that the addition of L-His and L-Lys has It may promote the degradation of protein by calpain through positive effects on protein phosphorylation level,and affect muscle contraction and post-mortem rigidity and maturation process.L-Lys and L-His under low salt conditions can affect post-mortem meat quality by adjusting protein phosphorylation levels.3.Mechanism of L-lysine and L-histidine influencing the phosphorylation of post-mortem chicken protein.In this part of the experiment,after marinating chicken breasts and drumsticks with NaCl and L-Lys and L-His for 16h,using the isobaric multi-tag relative quantitative proteomics(TMT)technology,3558 phosphorylation sites identified on 1261 proteins.Bioinformatics results show that the addition of L-Lys mainly reduces the phosphorylation level of related proteins involved in the actin cytoskeleton,sugar metabolism pathways,etc.The addition of L-His mainly reduces myofibers,contractility and supramolecular fibers,Molecular polymers and complexes,parts of contractile fibers,actin cytoskeleton,myosin complexes and phosphorylation levels of ribose phosphate,nucleoside and nucleoside phosphate related metabolic processes.Studies have shown that L-Lys and L-His mediated phosphorylation pathways of chicken thigh and chicken breast proteins are similar,and the resulting differential phosphorylated proteins are mainly involved in cellular processes,single life processes,biological regulation,and metabolic processes,and play a role of connection and catalysis.