Abstract Unpredictable variation in quality, including fresh pork water-holding capacity, remains challenging to pork processors and customers. Defining the diverse factors that influence fresh pork water-holding capacity is necessary to make progress in refining pork quality prediction methods. The objective was to utilize liquid chromatography and mass spectrometry coupled with tandem mass tag (TMT) multiplexing to evaluate the sarcoplasmic proteome of aged pork loins classified by purge loss. Fresh commercial pork loins were collected, aged 12 or 14 d postmortem, and pork quality and sensory attributes were evaluated. Chops were classified into Low (N = 27, average purge = 0.33%), Intermediate (N = 27, average purge = 0.72%), or High (N = 27, average purge = 1.19%) chop purge groups. Proteins soluble in a low-ionic strength buffer were extracted, digested with trypsin, labeled with 11-plex isobaric TMT reagents, and detected using a Q-Exactive Mass Spectrometer. Between the Low and High purge groups, 40 proteins were differentially (P < 0.05) abundant. The Low purge group had a greater abundance of proteins classified as structural and contractile, sarcoplasmic reticulum and calcium regulating, chaperone, and citric acid cycle enzymes than the High purge group. The presence of myofibrillar proteins in the aged sarcoplasmic proteome is likely due to postmortem degradation. These observations support our hypothesis that pork chops with low purge have a greater abundance of structural proteins in the soluble protein fraction. Together, these and other proteins in the aged sarcoplasmic proteome may be biomarkers of pork water-holding capacity. Additional research should establish the utility of these proteins as biomarkers early postmortem and over subsequent aging periods.
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Distinct myofibrillar sub-proteomic profiles are associated with the instrumental texture of aged pork loin
Fresh pork tenderness contributes to consumer satisfaction with the eating experience. Postmortem proteolysis of proteins within and between myofibrils has been closely linked with pork tenderness development. A clear understanding of the molecular features associated with pork tenderness development will provide additional targets and open the door to new solutions to improve and make pork tenderness development more consistent. Therefore, the objective was to utilize liquid chromatography and mass spectrometry with tandem mass tag (TMT) multiplexing to evaluate myofibrillar sub-proteome differences between pork chops of different instrumental star probe values. Pork loins (N = 120) were collected from a commercial harvest facility at 24 h postmortem. Quality and sensory attributes were evaluated at 24 h postmortem and after ~2 weeks of postmortem aging. Pork chops were grouped into 4 groups based on instrumental star probe value (group A,x¯ = 4.23 kg, 3.43 to 4.55 kg; group B,x¯ = 4.79 kg, 4.66 to 5.00 kg; group C,x¯ = 5.43 kg, 5.20 to 5.64 kg; group D,x¯ = 6.21 kg, 5.70 to 7.41 kg; n = 25 per group). Myofibrillar proteins from the samples aged ~2 wk were fractionated, washed, and solubilized in 8.3 M urea, 2 M thiourea, and 1% dithiothreitol. Proteins were digested with trypsin, labeled with 11-plex isobaric TMT reagents, and identified and quantified using a Q-Exactive Mass Spectrometer. Between groups A and D, 54 protein groups were differentially abundant (adjusted P < 0.05). Group A had a greater abundance of proteins related to the thick and thin filament and a lesser abundance of Z-line-associated proteins and metabolic enzymes than group D chops. These data highlight that distinct myofibrillar sub-proteomes are associated with pork chops of different tenderness values. Future research should evaluate changes immediately and earlier postmortem to further elucidate myofibrillar sub-proteome differences over the postmortem aging period.
more » « less- Award ID(s):
- 1828942
- NSF-PAR ID:
- 10536306
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Animal Science
- Volume:
- 101
- ISSN:
- 0021-8812
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract The incidence of type 1 diabetes (T1D) and its associated risks of chronic kidney disease or end‐stage renal disease development are on the rise. T1D is an autoimmune disease in which insulin‐producing beta cells are destroyed. Increased incidence of T1D has been suggested to be a result of environmental factors such as exposure to polycyclic aromatic hydrocarbons (PAHs). 2‐aminoanthracene (2AA) is a PAH that has been associated with the onset of early diabetic symptoms. This study was conducted to assess if 2AA dietary ingestion would induce T1D renal injuries. To accomplish study goals, Sprague‐Dawley rats were assigned into three 2AA dietary (0, 50, and 100 mg/kg‐2AA) ingestion groups for 12 weeks. Animals were evaluated for various morphometric indices, clinical markers, and gene expression. The rats in the 100 mg/kg group lost 5% less weight than the other treatment groups and converted roughly 3% more of their food intake into body mass. Renal histopathology indicated no significant difference between groups. The kidney weight per bodyweight of the 100 mg/kg treatment group was 30.1% greater than the control group. Creatinine concentration of the 100 mg/kg group was 46.2% greater than the control group. Serum glucose levels were significantly elevated in rats exposed to 2AA. On the contrary, serum albumin concentration was significantly reduced in 2AA‐treated rats. T1D and genetic markers of renal injury such as FABP1, SPP1, IL‐1B, and IL‐7 were elevated in treated groups. These results suggest that 2AA may induce the early diabetic renal injuries.
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Background Mechanisms of smell loss in chronic rhinosinusitis (CRS) are still unclear and likely multifactorial. Little attention has been given to olfactory cleft (OC) mucus proteins involved in odorant binding and metabolizing enzymes and their potential role in smell loss.
Methods Mucus from the OC was sampled from patients with CRS (n = 20) and controls (n = 10). Liquid chromatography and mass spectrometry were performed, followed by data processing so that protein groups could be identified, quantified, and compared. Hierarchical clustering and bioinformatic analysis were performed on significantly different proteins to explore for enrichment in known biologic pathways.
Results A total of 2514 proteins were found in OC mucus from all 30 subjects. Significant differences in protein abundance were found between CRS and controls, including both CRSsNP (n = 351 proteins; log2fold change range: –3.88 to 6.71) and CRSwNP (n = 298 proteins; log2fold change range: –4.00 to –6.13). Significant differences were found between patients with normosmia and those with dysosmia (n = 183; log2fold change range: –3.62 to –2.16) and across groups of interest for a number of odorant binding proteins and metabolizing enzymes.
Conclusion OC mucous in CRS displays a rich and abundant array of proteins, many of which have been implicated in odorant transport and metabolization in animal studies. Significant differences in the olfactory mucus proteome were seen between CRS subtypes and controls, as well as between those with normal and abnormal olfaction. Further study should confirm these findings and explore the role individual proteins play in odorant transport and metabolization. ©2020 ARSAAOA, LLC.
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/jas/skad327
