A Pickering emulsion based on sodium starch octenyl succinate(SSOS)was prepared and its effects on the physicochemical properties of hairtail myofibrillar protein gels(MPGs)subjected to multiple freeze-thaw(F-T)cycles...A Pickering emulsion based on sodium starch octenyl succinate(SSOS)was prepared and its effects on the physicochemical properties of hairtail myofibrillar protein gels(MPGs)subjected to multiple freeze-thaw(F-T)cycles were investigated.The whiteness,water-holding capacity,storage modulus(G')and texture properties of the MPGs were significantly improved by adding 1%-2%Pickering emulsion(P<0.05).Meanwhile,Raman spectral analysis demonstrated that Pickering emulsion promoted the transformation of secondary structure,enhanced hydrogen bonds and hydrophobic interactions,and promoted the transition of disulfide bond conformation from g-g-g to g-g-t and t-g-t.At an emulsion concentration of 2%,theα-helix content decreased by 10.37%,while theβ-sheet content increased by 7.94%,compared to the control.After F-T cycles,the structure of the MPGs was destroyed,with an increase in hardness and a decrease in whiteness and water-holding capacity,however,the quality degradation of MPGs was reduced with 1%-2%Pickering emulsion.These findings demonstrated that SSOS-Pickering emulsions,as potential fat substitutes,can enhance the gel properties and the F-T stability of MPGs.展开更多
Investigation that protein oxidation to the formation of advanced glycation end products(AGEs)after chicken myofibrillar protein glycation is limited.Models of protein oxidation induced by different concentrations of ...Investigation that protein oxidation to the formation of advanced glycation end products(AGEs)after chicken myofibrillar protein glycation is limited.Models of protein oxidation induced by different concentrations of hydroxyl radicals(·OH)were developed after the chicken myofibrillar protein mild glycation(MPG).Results exhibited that levels of AGEs and surface hydrophobicity(H_(0))steadily increased with the a ddition of h ydrogen peroxide(H_(2)O_(2))concentration.However,levels of s ulfhydryl group,free amino group,and particle size gradually decreased with the H_(2)O_(2)concentration.The protein carbonyl value increased in H_(2)O_(2)concentration until 10 mmol/L.Pearson's correlation indicated that MPG structure modification(unfolding and degradation)induced by protein oxidation were significantly positively correlated with AGEs concentration(P<0.05).Finally,a mechanism was proposed to hypothesize t he effect of protein oxidation on the formation of AGEs under MPG conditions.展开更多
This study aimed to examine changes in phosphorylation of sarcoplasmic and myofibrillar proteins from longissimus lumborum,semitendinosus,and psoas major muscles during postmortem ageing for 5 d.These sarcoplasmic and...This study aimed to examine changes in phosphorylation of sarcoplasmic and myofibrillar proteins from longissimus lumborum,semitendinosus,and psoas major muscles during postmortem ageing for 5 d.These sarcoplasmic and myofibrillar proteins were separated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and stained with phosphorous and protein specific stains.Myofibril fragmentation index,pH,the content of lactic acid and the relative activity of μ-calpain in three ovine muscles were measured.These results showed that the relative phosphorylation level of sarcoplasmic and myofibrillar proteins of psoas major muscle were lower compared with longissimus lumborum and semitendinosus muscles(P<0.05).The pH of psoas major muscle was the lowest at 0.5 h postmortem,and the highest after 12 h postmortem(P<0.05).In addition,the relative activity of μ-calpain was higher within 5 d postmortem and myofibril fragmentation index was higher after 1 d postmortem in psoas major muscle than those of longissimus lumborum and semitendinosus muscles(P<0.05).The sarcoplasmic protein phosphorylation may regulate the rate of pH decline to influence the μ-calpain activity and then proteolysis of proteins consequently.This study gives a new perspective of the mechanism of postmortem meat tenderization.展开更多
Phosphorylation post-translational modification plays an important role in postmortem muscle quality traits. Adenosine triphosphate(ATP) is an energy source and a key substrate of phosphorylation which provides the ph...Phosphorylation post-translational modification plays an important role in postmortem muscle quality traits. Adenosine triphosphate(ATP) is an energy source and a key substrate of phosphorylation which provides the phosphatase groups to proteins in the presence of protein kinases. However, in postmortem muscle, the effects of ATP content on phosphorylation are poorly studied. The study investigated the effect of ATP on protein phosphorylation and degradation in postmortem ovine muscle. The ground muscle with/without additional ATP were treated/control groups and stored at 25 and 4℃, respectively. The ATP content led to different changes of p H value between the ATP-treated and control groups. The phosphorylation level of myofibrillar proteins was higher(P<0.05) in ATP-treated group compared to the control group at both temperatures, which suggested that ATP played a vital role in postmortem protein phosphorylation. A slower degradation rate of μ-calpain, desmin and troponin T was observed in the ATP-treated group which showed that there was a negative relationship between ATP level and the degradation of proteins. These observations clearly highlighted the role of ATP on the development of meat quality by regulating the phosphorylation and degradation of myofibrillar proteins in postmortem ovine muscle.展开更多
Background: Improving the unsaturated fatty acid content of ruminant meat is essential due to the generally saturated nature of fatty acids in ruminant meat and the negative effects this can have on human health. None...Background: Improving the unsaturated fatty acid content of ruminant meat is essential due to the generally saturated nature of fatty acids in ruminant meat and the negative effects this can have on human health. Nonetheless, enhancing the unsaturated fatty acid content of ruminant meat can have adverse effects on the shelf life and quality attributes of the meat. This study assessed the effects of dietary 80 % canola oil and 20 % palm oil blend(CPOB) on fatty acid composition, antioxidants, oxidative spoilage, cholesterol and physicochemical properties of semimembranosus(SM)muscle from goats. Twenty four Boer bucks were randomly assigned to diets containing on dry matter basis 0, 4 and8 % CPOB, fed for 100 d and slaughtered. The carcasses were subjected to a 7 d postmortem refrigerated storage. Al analyses were conducted on the SM muscle.Results: Diet had no effect(P > 0.05) on the concentration of free thiol and carbonyl and the band intensity of myosin heavy chain, actin and troponin T. The muscle glycogen, p H, water holding capacity, tenderness, glutathione peroxidase(GPX) activity, total carotenoid, δ-tocopherol, cholesterol and proximate composition did not differ(P > 0.05) between diets. The SM muscle from goats fed 4 and 8 % CPOB had lower(P < 0.05) concentration of C14:0 and C16:0 and higher(P < 0.05) concentration of C18:1 trans-11, C18:1ω-9, C18:3ω-3, C20:5ω-3 and C22:5ω-3 than the SM muscle from the control goats. Dietary CPOB increased(P < 0.05) the concentration of α and γ tocopherol and meat redness(a*) on d1 and 4 postmortem. Regardless of diet, antioxidant vitamins, and shear force decreased(P < 0.05) while drip loss, lipid and protein oxidation increased(P < 0.05) as postmortem storage progressed.Conclusion: Results evince that dietary CPOB can be used as a management tool to enhance the beneficial fatty acids and antioxidant contents of chevon without deleterious effects on its physicochemical properties and shelf life.展开更多
This study aimed to investigate the effects of phosphorylated-ovalbumin(P-OVA)at different concentrations(0.5%and 1.0%)on the gel properties of pork myofibrillar protein(MP).The results showed that the textural proper...This study aimed to investigate the effects of phosphorylated-ovalbumin(P-OVA)at different concentrations(0.5%and 1.0%)on the gel properties of pork myofibrillar protein(MP).The results showed that the textural properties such as gel hardness,cohesiveness,springiness and chewiness were improved with P-OVA addition at 0.5%.The water holding capacity(up to 75.89%)and gel strength(up to 168.56 g·mm)of MP gel were markedly increased after P-OVA addition.The absolute value of zeta potential reached 13.85 mV and maximum hydrophobicity(15.2μg)resulted from the addition of 0.5%P-OVA.The storage modulus(G’)and loss modulus(G’’)of MP gel were significantly increased from 50°C,and the G’and G’’significantly increased after 1.0%P-OVA addition,evidencing that the cross-linking effect of MP protein gel was enhanced.In addition,the P-OVA addition improved the structure of MP gel protein by reducing theα-helix,while increasing theβ-sheet and the r-value(the ratio between two ultraviolet second-derivative peak-to-trough distances),which further promoted the uniform and compact gel network structure.This work demonstrated that P-OVA is a highly effective modifier that significantly improves the quality of MP gel.From a view of practice,0.5%P-OVA is the optimal addition amount.展开更多
Changes in protein quality during ice storage affects the muscle structure,the textural quality,functional properties and the eating quality.Dynamic viscoelastic behaviour and gelling properties ofmeat proteinsin rela...Changes in protein quality during ice storage affects the muscle structure,the textural quality,functional properties and the eating quality.Dynamic viscoelastic behaviour and gelling properties ofmeat proteinsin relation to histological changes in white leg shrimp muscles were assessed for 14 days in ice storage.Reduction in Ca2+ATPase activity of fresh myofibrillar protein(MFP),fading of myosin banding pattern and increased gapping in myofibrils were clearly observed with progress of storage.The quality indices of the shrimp muscle were well correlated with histological and functional properties as a function of ice storage.Solubility of fresh MFP was 86.76%which decreased to 77.06%on the 14th day of storage period.Emulsion capacity found to increase during storage period.Gel strength of white leg shrimp meat was low(81±14 g cm)and further,reduced nearly 60%compared to fresh sample at the end of storage.The considerable reductions(from 535.77 kPa to 246.56 kPa)in storage modulus values were evident of diminishing elasticity and gelling ability of the meat due to ice storage.Therefore,this study usherd that the histological deterioration in myofibrils may be used as an indication of diminishing biochemical quality and gelling behaviour of the proteins.展开更多
The effects of the microwave combined with air convection thawing(MAT)on the gelling properties of pork myofibrillar proteins(MPs)were further studied and compared with those of fresh meat(FM),and single thawing metho...The effects of the microwave combined with air convection thawing(MAT)on the gelling properties of pork myofibrillar proteins(MPs)were further studied and compared with those of fresh meat(FM),and single thawing methods(microwave thawing(MT)and air convection thawing(AT)).Results revealed that the thawing methods,excluding MAT,induced deterioration in the gelling properties of MPs.There was no significant difference(p>0.05)in the water holding capacity(WHC),cooking loss,whiteness,and strength of gel samples subjected to MAT and those of FM samples,demonstrating that the gelling properties were retained after MAT.As well,protein aggregation was limited,since MAT reduced the change in zeta potential and turbidity compared to that observed with MT or AT.The dynamic rheology and scanning electron microscopic results were relatively consistent,revealing that among the different thawing techniques,MAT had the least negative impact on the microstructure of MPs gel,leading to the generation of a more elastic and uniform gel structure than that of the MT or AT gels.Moreover,MAT resulted in higher water retention in the gels than that achieved with MT or AT.These findings indicated that MAT improved the gelling properties of MPs,thereby confirming the suitability of this treatment for use in the meat processing industry.展开更多
Objectives:The nutrient rich sea bass is prone to oxidation of lipid and protein during refrigeration.Materials and Methods:The research was to investigate the effect of different concentrations of Melissa officinalis...Objectives:The nutrient rich sea bass is prone to oxidation of lipid and protein during refrigeration.Materials and Methods:The research was to investigate the effect of different concentrations of Melissa officinalis L.essential oil(MOEO)nanoemulsions on myofibrillar protein(MP)and lipid oxidation in sea bass(Lateolabrax japonicus)during refrigeration at 4°C.Results:The results of thiobarbituric acid reactive substances and mitochondrial membrane potential showed that carboxymethyl chitosan/locust bean gum active coating solutions incorporating 2%MOEO nanoemulsions(C/L-2M)was the most effective in inhibiting lipid oxidation that occurred in sea bass under attack by reactive oxygen species.Low-field nuclear magnetic resonance results showed that C/L-2M maximally slowed the conversion of bound water to free water during storage.The oxidation of lipids and MP disrupted the secondary and tertiary conformations of MP and accelerated protein aggregation and degradation.Conclusions:C/L-2M slowed the oxidation of lipids and proteins by inhibiting the oxidation of reactive oxygen species.C/L-2M is a very promising preservative emulsion for the preservation of sea bass.展开更多
Essential proteins are inseparable in cell growth and survival. The study of essential proteins is important for understanding cellular functions and biological mechanisms. Therefore, various computable methods have b...Essential proteins are inseparable in cell growth and survival. The study of essential proteins is important for understanding cellular functions and biological mechanisms. Therefore, various computable methods have been proposed to identify essential proteins. Unfortunately, most methods based on network topology only consider the interactions between a protein and its neighboring proteins, and not the interactions with its higher-order distance proteins. In this paper, we propose the DSEP algorithm in which we integrated network topology properties and subcellular localization information in protein–protein interaction(PPI) networks based on four-order distances, and then used random walks to identify the essential proteins. We also propose a method to calculate the finite-order distance of the network, which can greatly reduce the time complexity of our algorithm. We conducted a comprehensive comparison of the DSEP algorithm with 11 existing classical algorithms to identify essential proteins with multiple evaluation methods. The results show that DSEP is superior to these 11 methods.展开更多
Globally,the prevalence of anxiety and depression has reached epidemic proportions.Food-derived protein hydrolysates and peptides delivered through dietary supplementation can avoid the negative risks associated with ...Globally,the prevalence of anxiety and depression has reached epidemic proportions.Food-derived protein hydrolysates and peptides delivered through dietary supplementation can avoid the negative risks associated with traditional pharmaceuticals while delivering superior anxiolytic and antidepressant effects.This review summarizes current research on food-derived anxiolytic and antidepressant protein hydrolysates and peptides,and subsequently analyses their physicochemical characteristics and elaborates on their mechanisms.The aim of this work is to contribute to the in-depth study and provide a theoretical foundation for the development of related products to better serve patients with anxiety and depression.展开更多
Cowpea (Vigna unguiculata L. Walp) is a multi-purpose legume with high quality protein for human consumption and livestock. The objective of this work was to develop near-infrared spectroscopy (NIRS) prediction models...Cowpea (Vigna unguiculata L. Walp) is a multi-purpose legume with high quality protein for human consumption and livestock. The objective of this work was to develop near-infrared spectroscopy (NIRS) prediction models to estimate protein content in cowpea. A total of 116 cowpea breeding lines with a wide range of protein contents (19.28 % to 32.04%) were selected to build the model using whole seed and ground seed samples. Partial least-squares discriminant analysis (PLS-DA) regression technique with different pre-treatments (derivatives, standard normal variate, and multiplicative scatter correction) were carried out to develop the protein prediction model. Results showed: 1) spectral plots of both the whole seed and ground seed showed higher spectral scatter at higher wavelengths (>1450 nm), 2) data pre-processing affects prediction accuracy for bot whole seed and ground seed samples, 3) prediction using ground seed samples (0.64 R<sup>2</sup> 0.85) is better than the whole seed (0.33 R<sup>2</sup> 0.78), and 4) the data pre-processing second derivative with standard normal variate has the best prediction (R<sup>2</sup>_whole seed = 0.78, R<sup>2</sup>_ground seed = 0.85). The results will be of interest in cowpea breeding programs aimed at improving total seed protein content.展开更多
The unfolded protein response(UPR)is a cellular stress response pathway activated when the endoplasmic reticulum,a crucial organelle for protein folding and modification,encounters an accumulation of unfolded or misfo...The unfolded protein response(UPR)is a cellular stress response pathway activated when the endoplasmic reticulum,a crucial organelle for protein folding and modification,encounters an accumulation of unfolded or misfolded proteins.The UPR aims to restore endoplasmic reticulum homeostasis by enhancing protein folding capacity,reducing protein biosynthesis,and promoting protein degradation.It also plays a pivotal role in coordinating signaling cascades to determine cell fate and function in response to endoplasmic reticulum stress.Recent research has highlighted the significance of the UPR not only in maintaining endoplasmic reticulum homeostasis but also in influencing various physiological processes in the nervous system.Here,we provide an overview of recent findings that underscore the UPR’s involvement in preserving the function and viability of neuronal and myelinating cells under physiological conditions,and highlight the critical role of the UPR in brain development,memory storage,retinal cone development,myelination,and maintenance of myelin thickness.展开更多
Changes in protein abundance and reversible protein phosphorylation(RPP)play important roles in regulating hypometabolism but have never been documented in overwintering frogs at high altitudes.To test the hypothesis ...Changes in protein abundance and reversible protein phosphorylation(RPP)play important roles in regulating hypometabolism but have never been documented in overwintering frogs at high altitudes.To test the hypothesis that protein abundance and phosphorylation change in response to winter hibernation,we conducted a comprehensive and quantitative proteomic and phosphoproteomic analysis of the liver of the Xizang plateau frog,Nanorana parkeri,living on the Qinghai-Xizang Plateau.In total,5170 proteins and 5695 phosphorylation sites in 1938 proteins were quantified.Based on proteomic analysis,674 differentially expressed proteins(438 up-regulated,236 down-regulated)were screened in hibernating N.parkeri versus summer individuals.Functional enrichment analysis revealed that higher expressed proteins in winter were significantly enriched in immune-related signaling pathways,whereas lower expressed proteins were mainly involved in metabolic processes.A total of 4251 modified sites(4147 up-regulated,104 down-regulated)belonging to 1638 phosphoproteins(1555 up-regulated,83 down-regulated)were significantly changed in the liver.During hibernation,RPP regulated a diverse array of proteins involved in multiple functions,including metabolic enzymatic activity,ion transport,protein turnover,signal transduction,and alternative splicing.These changes contribute to enhancing protection,suppressing energy-consuming processes,and inducing metabolic depression.Moreover,the activities of phosphofructokinase,glutamate dehydrogenase,and ATPase were all significantly lower in winter compared to summer.In conclusion,our results support the hypothesis and demonstrate the importance of RPP as a regulatory mechanism when animals transition into a hypometabolic state.展开更多
In this study,we investigated the effects of major royal jelly proteins(MRJPs)on the estrogen,gut microbiota,and immunological responses in mice.Mice given 250 or 500 mg/kg,not 125 mg/kg of MRJPs,enhanced the prolifer...In this study,we investigated the effects of major royal jelly proteins(MRJPs)on the estrogen,gut microbiota,and immunological responses in mice.Mice given 250 or 500 mg/kg,not 125 mg/kg of MRJPs,enhanced the proliferation of splenocytes in response to mitogens.The splenocytes and mesenteric lymphocytes activated by T-cell mitogens(Con A and anti-CD3/CD28 antibodies)released high levels of IL-2 but low levels of IFN-γand IL-17A.The release of IL-4 was unaffected by MRJPs.Additionally,splenocytes and mesenteric lymphocytes activated by LPS were prevented by MRJPs at the same dose as that required for producing IL-1βand IL-6,two pro-inflammatory cytokines.The production of IL-1β,IL-6,and IFN-γwas negatively associated with estrogen levels,which were higher in the MRJP-treated animals than in the control group.Analysis of the gut microbiota revealed that feeding mice 250 mg/kg of MRJPs maintained the stability of the natural intestinal microflora of mice.Additionally,the LEf Se analysis identified biomarkers in the MRJP-treated mice,including Prevotella,Bacillales,Enterobacteriales,Gammaproteobacteria,Candidatus_Arthromitus,and Shigella.Our results showed that MRJPs are important components of royal jelly that modulate host immunity and hormone levels and help maintain gut microbiota stability.展开更多
AIM:To explore the therapeutic effect and main molecular mechanisms of acteoside in a glaucoma model in DBA/2J mice.METHODS:Proteomics was used to compare the differentially expressed proteins of C57 and DBA/2J mice.A...AIM:To explore the therapeutic effect and main molecular mechanisms of acteoside in a glaucoma model in DBA/2J mice.METHODS:Proteomics was used to compare the differentially expressed proteins of C57 and DBA/2J mice.After acteoside administration in DBA/2J mice,anterior segment observation,intraocular pressure(IOP)monitoring,electrophysiology examination,and hematoxylin and eosin staining were used to analyze any potential effects.Immunohistochemistry(IHC)assays were used to verify the proteomics results.Furthermore,retinal ganglion cell 5(RGC5)cell proliferation was assessed with cell counting kit-8(CCK-8)assays.Serta domain-containing protein 4(Sertad4)mRNA and protein expression levels were measured by qRT-PCR and Western blot analysis,respectively.RESULTS:Proteomics analysis suggested that Sertad4 was the most significantly differentially expressed protein.Compared with the saline group,the acteoside treatment group showed decreased IOP,improved N1-P1 wave amplitudes,thicker retina,and larger numbers of cells in the ganglion cell layer(GCL).The IHC results showed that Sertad4 expression levels in DBA/2J mice treated with acteoside were significantly lower than in the saline group.Acteoside treatment could improve RGC5 cell survival and reduce the Sertad4 mRNA and protein expression levels after glutamate injury.CONCLUSION:Sertad4 is differentially expressed in DBA/2J mice.Acteoside can protect RGCs from damage,possibly through the downregulation of Sertad4,and has a potential use in glaucoma treatment.展开更多
Light plays an important role in the photosynthesis and metabolic process of microalgae.However,how different light conditions regulate the biomass production and protein accumulation of microalgae is mostly unknown.I...Light plays an important role in the photosynthesis and metabolic process of microalgae.However,how different light conditions regulate the biomass production and protein accumulation of microalgae is mostly unknown.In this study,the influence of different light conditions,including light colors,densities,and light:dark cycles on the cell growth and biochemical composition of Spirulina platensis was symmetrically characterized.Under different colored lights,S.platensis all shows an increase trend within the increased light intensity ranges;however,each showing different optimal light intensities.At the same light intensity,different colored lights show different growth rate of S.platensis following the sequence of red>white>green>yellow>blue.The maximum growth rate and protein accumulation were determined as 21.88 and 5.10 mg/(L·d)when illuminated under red LED.The energy efficiency of different light sources was calculated and ranked as red>white>blue≈green>yellow.Transcriptomic analysis suggests that red light can promote cell growth and protein accumulation by upregulating genes related to photosynthesis,carbon fixation,and C-N metabolism pathways.This study provides a conducive and efficient way to promote biomass production and protein accumulation of S.platensis by regulating light conditions.展开更多
The rapid advancement and broad application of machine learning(ML)have driven a groundbreaking revolution in computational biology.One of the most cutting-edge and important applications of ML is its integration with...The rapid advancement and broad application of machine learning(ML)have driven a groundbreaking revolution in computational biology.One of the most cutting-edge and important applications of ML is its integration with molecular simulations to improve the sampling efficiency of the vast conformational space of large biomolecules.This review focuses on recent studies that utilize ML-based techniques in the exploration of protein conformational landscape.We first highlight the recent development of ML-aided enhanced sampling methods,including heuristic algorithms and neural networks that are designed to refine the selection of reaction coordinates for the construction of bias potential,or facilitate the exploration of the unsampled region of the energy landscape.Further,we review the development of autoencoder based methods that combine molecular simulations and deep learning to expand the search for protein conformations.Lastly,we discuss the cutting-edge methodologies for the one-shot generation of protein conformations with precise Boltzmann weights.Collectively,this review demonstrates the promising potential of machine learning in revolutionizing our insight into the complex conformational ensembles of proteins.展开更多
The onset of amyotrophic lateral sclerosis is usually characterized by focal death of both upper and/or lower motor neurons occurring in the motor cortex,basal ganglia,brainstem,and spinal cord,and commonly involves t...The onset of amyotrophic lateral sclerosis is usually characterized by focal death of both upper and/or lower motor neurons occurring in the motor cortex,basal ganglia,brainstem,and spinal cord,and commonly involves the muscles of the upper and/or lower extremities,and the muscles of the bulbar and/or respiratory regions.However,as the disease progresses,it affects the adjacent body regions,leading to generalized muscle weakness,occasionally along with memory,cognitive,behavioral,and language impairments;respiratory dysfunction occurs at the final stage of the disease.The disease has a complicated pathophysiology and currently,only riluzole,edaravone,and phenylbutyrate/taurursodiol are licensed to treat amyotrophic lateral sclerosis in many industrialized countries.The TAR DNA-binding protein 43 inclusions are observed in 97%of those diagnosed with amyotrophic lateral sclerosis.This review provides a preliminary overview of the potential effects of TAR DNAbinding protein 43 in the pathogenesis of amyotrophic lateral sclerosis,including the abnormalities in nucleoplasmic transport,RNA function,post-translational modification,liquid-liquid phase separation,stress granules,mitochondrial dysfunction,oxidative stress,axonal transport,protein quality control system,and non-cellular autonomous functions(e.g.,glial cell functions and prion-like propagation).展开更多
基金supported by the National Natural Science Foundation of China(U20A2067,32272360)。
文摘A Pickering emulsion based on sodium starch octenyl succinate(SSOS)was prepared and its effects on the physicochemical properties of hairtail myofibrillar protein gels(MPGs)subjected to multiple freeze-thaw(F-T)cycles were investigated.The whiteness,water-holding capacity,storage modulus(G')and texture properties of the MPGs were significantly improved by adding 1%-2%Pickering emulsion(P<0.05).Meanwhile,Raman spectral analysis demonstrated that Pickering emulsion promoted the transformation of secondary structure,enhanced hydrogen bonds and hydrophobic interactions,and promoted the transition of disulfide bond conformation from g-g-g to g-g-t and t-g-t.At an emulsion concentration of 2%,theα-helix content decreased by 10.37%,while theβ-sheet content increased by 7.94%,compared to the control.After F-T cycles,the structure of the MPGs was destroyed,with an increase in hardness and a decrease in whiteness and water-holding capacity,however,the quality degradation of MPGs was reduced with 1%-2%Pickering emulsion.These findings demonstrated that SSOS-Pickering emulsions,as potential fat substitutes,can enhance the gel properties and the F-T stability of MPGs.
基金supported by National Key R&D Program of China(2021YFD2100104)griculture Research System of China(CARS-41-Z)+2 种基金Science and Technology Project of Nanjing City(202002040)Jiangsu Province Policy Guidance Program(BX2020008)Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX21_0579),China。
文摘Investigation that protein oxidation to the formation of advanced glycation end products(AGEs)after chicken myofibrillar protein glycation is limited.Models of protein oxidation induced by different concentrations of hydroxyl radicals(·OH)were developed after the chicken myofibrillar protein mild glycation(MPG).Results exhibited that levels of AGEs and surface hydrophobicity(H_(0))steadily increased with the a ddition of h ydrogen peroxide(H_(2)O_(2))concentration.However,levels of s ulfhydryl group,free amino group,and particle size gradually decreased with the H_(2)O_(2)concentration.The protein carbonyl value increased in H_(2)O_(2)concentration until 10 mmol/L.Pearson's correlation indicated that MPG structure modification(unfolding and degradation)induced by protein oxidation were significantly positively correlated with AGEs concentration(P<0.05).Finally,a mechanism was proposed to hypothesize t he effect of protein oxidation on the formation of AGEs under MPG conditions.
基金funded by the National Agricultural Science and Technology Innovation Program in China
文摘This study aimed to examine changes in phosphorylation of sarcoplasmic and myofibrillar proteins from longissimus lumborum,semitendinosus,and psoas major muscles during postmortem ageing for 5 d.These sarcoplasmic and myofibrillar proteins were separated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and stained with phosphorous and protein specific stains.Myofibril fragmentation index,pH,the content of lactic acid and the relative activity of μ-calpain in three ovine muscles were measured.These results showed that the relative phosphorylation level of sarcoplasmic and myofibrillar proteins of psoas major muscle were lower compared with longissimus lumborum and semitendinosus muscles(P<0.05).The pH of psoas major muscle was the lowest at 0.5 h postmortem,and the highest after 12 h postmortem(P<0.05).In addition,the relative activity of μ-calpain was higher within 5 d postmortem and myofibril fragmentation index was higher after 1 d postmortem in psoas major muscle than those of longissimus lumborum and semitendinosus muscles(P<0.05).The sarcoplasmic protein phosphorylation may regulate the rate of pH decline to influence the μ-calpain activity and then proteolysis of proteins consequently.This study gives a new perspective of the mechanism of postmortem meat tenderization.
基金financial support from the National Natural Science Foundation of China (31771995)the earmarked fund for China Agriculture Research System (CARS-38)the Agricultural Science and Technology Innovation Program, Chinese Academy of Agricultural Sciences (CAAS-ASTIP-IFST)。
文摘Phosphorylation post-translational modification plays an important role in postmortem muscle quality traits. Adenosine triphosphate(ATP) is an energy source and a key substrate of phosphorylation which provides the phosphatase groups to proteins in the presence of protein kinases. However, in postmortem muscle, the effects of ATP content on phosphorylation are poorly studied. The study investigated the effect of ATP on protein phosphorylation and degradation in postmortem ovine muscle. The ground muscle with/without additional ATP were treated/control groups and stored at 25 and 4℃, respectively. The ATP content led to different changes of p H value between the ATP-treated and control groups. The phosphorylation level of myofibrillar proteins was higher(P<0.05) in ATP-treated group compared to the control group at both temperatures, which suggested that ATP played a vital role in postmortem protein phosphorylation. A slower degradation rate of μ-calpain, desmin and troponin T was observed in the ATP-treated group which showed that there was a negative relationship between ATP level and the degradation of proteins. These observations clearly highlighted the role of ATP on the development of meat quality by regulating the phosphorylation and degradation of myofibrillar proteins in postmortem ovine muscle.
文摘Background: Improving the unsaturated fatty acid content of ruminant meat is essential due to the generally saturated nature of fatty acids in ruminant meat and the negative effects this can have on human health. Nonetheless, enhancing the unsaturated fatty acid content of ruminant meat can have adverse effects on the shelf life and quality attributes of the meat. This study assessed the effects of dietary 80 % canola oil and 20 % palm oil blend(CPOB) on fatty acid composition, antioxidants, oxidative spoilage, cholesterol and physicochemical properties of semimembranosus(SM)muscle from goats. Twenty four Boer bucks were randomly assigned to diets containing on dry matter basis 0, 4 and8 % CPOB, fed for 100 d and slaughtered. The carcasses were subjected to a 7 d postmortem refrigerated storage. Al analyses were conducted on the SM muscle.Results: Diet had no effect(P > 0.05) on the concentration of free thiol and carbonyl and the band intensity of myosin heavy chain, actin and troponin T. The muscle glycogen, p H, water holding capacity, tenderness, glutathione peroxidase(GPX) activity, total carotenoid, δ-tocopherol, cholesterol and proximate composition did not differ(P > 0.05) between diets. The SM muscle from goats fed 4 and 8 % CPOB had lower(P < 0.05) concentration of C14:0 and C16:0 and higher(P < 0.05) concentration of C18:1 trans-11, C18:1ω-9, C18:3ω-3, C20:5ω-3 and C22:5ω-3 than the SM muscle from the control goats. Dietary CPOB increased(P < 0.05) the concentration of α and γ tocopherol and meat redness(a*) on d1 and 4 postmortem. Regardless of diet, antioxidant vitamins, and shear force decreased(P < 0.05) while drip loss, lipid and protein oxidation increased(P < 0.05) as postmortem storage progressed.Conclusion: Results evince that dietary CPOB can be used as a management tool to enhance the beneficial fatty acids and antioxidant contents of chevon without deleterious effects on its physicochemical properties and shelf life.
基金the Innovation-Driven Development Capacity Enhancement Fund of Shanxi Province(SXYBKY2019041)National Key Research and Development Program(2021YFD1600604-03)+1 种基金Shanxi Scholarship Council of China(2021-068)Shanxi Agricultural University High-Level Talent Project(2021XG013).
文摘This study aimed to investigate the effects of phosphorylated-ovalbumin(P-OVA)at different concentrations(0.5%and 1.0%)on the gel properties of pork myofibrillar protein(MP).The results showed that the textural properties such as gel hardness,cohesiveness,springiness and chewiness were improved with P-OVA addition at 0.5%.The water holding capacity(up to 75.89%)and gel strength(up to 168.56 g·mm)of MP gel were markedly increased after P-OVA addition.The absolute value of zeta potential reached 13.85 mV and maximum hydrophobicity(15.2μg)resulted from the addition of 0.5%P-OVA.The storage modulus(G’)and loss modulus(G’’)of MP gel were significantly increased from 50°C,and the G’and G’’significantly increased after 1.0%P-OVA addition,evidencing that the cross-linking effect of MP protein gel was enhanced.In addition,the P-OVA addition improved the structure of MP gel protein by reducing theα-helix,while increasing theβ-sheet and the r-value(the ratio between two ultraviolet second-derivative peak-to-trough distances),which further promoted the uniform and compact gel network structure.This work demonstrated that P-OVA is a highly effective modifier that significantly improves the quality of MP gel.From a view of practice,0.5%P-OVA is the optimal addition amount.
文摘Changes in protein quality during ice storage affects the muscle structure,the textural quality,functional properties and the eating quality.Dynamic viscoelastic behaviour and gelling properties ofmeat proteinsin relation to histological changes in white leg shrimp muscles were assessed for 14 days in ice storage.Reduction in Ca2+ATPase activity of fresh myofibrillar protein(MFP),fading of myosin banding pattern and increased gapping in myofibrils were clearly observed with progress of storage.The quality indices of the shrimp muscle were well correlated with histological and functional properties as a function of ice storage.Solubility of fresh MFP was 86.76%which decreased to 77.06%on the 14th day of storage period.Emulsion capacity found to increase during storage period.Gel strength of white leg shrimp meat was low(81±14 g cm)and further,reduced nearly 60%compared to fresh sample at the end of storage.The considerable reductions(from 535.77 kPa to 246.56 kPa)in storage modulus values were evident of diminishing elasticity and gelling ability of the meat due to ice storage.Therefore,this study usherd that the histological deterioration in myofibrils may be used as an indication of diminishing biochemical quality and gelling behaviour of the proteins.
基金This study was supported by the Henan Province University Innovation Talents Support Program(No.22HASTIT043)the Young Scientists Sponsorship Program of Henan(No.2022 HYTP008)+1 种基金the Major Science and Technology Project of Henan Province(No.221100110500)the Science and Technology Research Project of Henan Province(No.232102110075).
文摘The effects of the microwave combined with air convection thawing(MAT)on the gelling properties of pork myofibrillar proteins(MPs)were further studied and compared with those of fresh meat(FM),and single thawing methods(microwave thawing(MT)and air convection thawing(AT)).Results revealed that the thawing methods,excluding MAT,induced deterioration in the gelling properties of MPs.There was no significant difference(p>0.05)in the water holding capacity(WHC),cooking loss,whiteness,and strength of gel samples subjected to MAT and those of FM samples,demonstrating that the gelling properties were retained after MAT.As well,protein aggregation was limited,since MAT reduced the change in zeta potential and turbidity compared to that observed with MT or AT.The dynamic rheology and scanning electron microscopic results were relatively consistent,revealing that among the different thawing techniques,MAT had the least negative impact on the microstructure of MPs gel,leading to the generation of a more elastic and uniform gel structure than that of the MT or AT gels.Moreover,MAT resulted in higher water retention in the gels than that achieved with MT or AT.These findings indicated that MAT improved the gelling properties of MPs,thereby confirming the suitability of this treatment for use in the meat processing industry.
基金supported by the China Agriculture Research System of MOF and MARA(CARS-47)the Shanghai Municipal Science and Technology Project to Enhance the Capabilities of the Platform(Nos.20DZ2292200 and 19DZ2284000),China.
文摘Objectives:The nutrient rich sea bass is prone to oxidation of lipid and protein during refrigeration.Materials and Methods:The research was to investigate the effect of different concentrations of Melissa officinalis L.essential oil(MOEO)nanoemulsions on myofibrillar protein(MP)and lipid oxidation in sea bass(Lateolabrax japonicus)during refrigeration at 4°C.Results:The results of thiobarbituric acid reactive substances and mitochondrial membrane potential showed that carboxymethyl chitosan/locust bean gum active coating solutions incorporating 2%MOEO nanoemulsions(C/L-2M)was the most effective in inhibiting lipid oxidation that occurred in sea bass under attack by reactive oxygen species.Low-field nuclear magnetic resonance results showed that C/L-2M maximally slowed the conversion of bound water to free water during storage.The oxidation of lipids and MP disrupted the secondary and tertiary conformations of MP and accelerated protein aggregation and degradation.Conclusions:C/L-2M slowed the oxidation of lipids and proteins by inhibiting the oxidation of reactive oxygen species.C/L-2M is a very promising preservative emulsion for the preservation of sea bass.
基金Project supported by the Gansu Province Industrial Support Plan (Grant No.2023CYZC-25)the Natural Science Foundation of Gansu Province (Grant No.23JRRA770)the National Natural Science Foundation of China (Grant No.62162040)。
文摘Essential proteins are inseparable in cell growth and survival. The study of essential proteins is important for understanding cellular functions and biological mechanisms. Therefore, various computable methods have been proposed to identify essential proteins. Unfortunately, most methods based on network topology only consider the interactions between a protein and its neighboring proteins, and not the interactions with its higher-order distance proteins. In this paper, we propose the DSEP algorithm in which we integrated network topology properties and subcellular localization information in protein–protein interaction(PPI) networks based on four-order distances, and then used random walks to identify the essential proteins. We also propose a method to calculate the finite-order distance of the network, which can greatly reduce the time complexity of our algorithm. We conducted a comprehensive comparison of the DSEP algorithm with 11 existing classical algorithms to identify essential proteins with multiple evaluation methods. The results show that DSEP is superior to these 11 methods.
基金supported by the National Key Research and Development Program of China (2021YFD2100402)the National Natural Science Foundation of China (81903275)the Fund of the Cultivation Project of Double First-Class Disciplines of Food Science and Engineering,Beijing Technology&Business University (BTBUYXTD202203)。
文摘Globally,the prevalence of anxiety and depression has reached epidemic proportions.Food-derived protein hydrolysates and peptides delivered through dietary supplementation can avoid the negative risks associated with traditional pharmaceuticals while delivering superior anxiolytic and antidepressant effects.This review summarizes current research on food-derived anxiolytic and antidepressant protein hydrolysates and peptides,and subsequently analyses their physicochemical characteristics and elaborates on their mechanisms.The aim of this work is to contribute to the in-depth study and provide a theoretical foundation for the development of related products to better serve patients with anxiety and depression.
文摘Cowpea (Vigna unguiculata L. Walp) is a multi-purpose legume with high quality protein for human consumption and livestock. The objective of this work was to develop near-infrared spectroscopy (NIRS) prediction models to estimate protein content in cowpea. A total of 116 cowpea breeding lines with a wide range of protein contents (19.28 % to 32.04%) were selected to build the model using whole seed and ground seed samples. Partial least-squares discriminant analysis (PLS-DA) regression technique with different pre-treatments (derivatives, standard normal variate, and multiplicative scatter correction) were carried out to develop the protein prediction model. Results showed: 1) spectral plots of both the whole seed and ground seed showed higher spectral scatter at higher wavelengths (>1450 nm), 2) data pre-processing affects prediction accuracy for bot whole seed and ground seed samples, 3) prediction using ground seed samples (0.64 R<sup>2</sup> 0.85) is better than the whole seed (0.33 R<sup>2</sup> 0.78), and 4) the data pre-processing second derivative with standard normal variate has the best prediction (R<sup>2</sup>_whole seed = 0.78, R<sup>2</sup>_ground seed = 0.85). The results will be of interest in cowpea breeding programs aimed at improving total seed protein content.
基金supported by grants from the National Institutes of Health,No.NS105689(to WL)the Department of Defense through the Multiple Sclerosis Research Program,No.W81XWH-22-1-0757(to WL).
文摘The unfolded protein response(UPR)is a cellular stress response pathway activated when the endoplasmic reticulum,a crucial organelle for protein folding and modification,encounters an accumulation of unfolded or misfolded proteins.The UPR aims to restore endoplasmic reticulum homeostasis by enhancing protein folding capacity,reducing protein biosynthesis,and promoting protein degradation.It also plays a pivotal role in coordinating signaling cascades to determine cell fate and function in response to endoplasmic reticulum stress.Recent research has highlighted the significance of the UPR not only in maintaining endoplasmic reticulum homeostasis but also in influencing various physiological processes in the nervous system.Here,we provide an overview of recent findings that underscore the UPR’s involvement in preserving the function and viability of neuronal and myelinating cells under physiological conditions,and highlight the critical role of the UPR in brain development,memory storage,retinal cone development,myelination,and maintenance of myelin thickness.
基金supported by the National Natural Science Foundation of China(32001110)Training Program for Cultivating Highlevel Talents by the China Scholarship Council(2021lxjjw01)Open Project of State Key Laboratory of Plateau Ecology and Agriculture,Qinghai University(2021-KF-004)。
文摘Changes in protein abundance and reversible protein phosphorylation(RPP)play important roles in regulating hypometabolism but have never been documented in overwintering frogs at high altitudes.To test the hypothesis that protein abundance and phosphorylation change in response to winter hibernation,we conducted a comprehensive and quantitative proteomic and phosphoproteomic analysis of the liver of the Xizang plateau frog,Nanorana parkeri,living on the Qinghai-Xizang Plateau.In total,5170 proteins and 5695 phosphorylation sites in 1938 proteins were quantified.Based on proteomic analysis,674 differentially expressed proteins(438 up-regulated,236 down-regulated)were screened in hibernating N.parkeri versus summer individuals.Functional enrichment analysis revealed that higher expressed proteins in winter were significantly enriched in immune-related signaling pathways,whereas lower expressed proteins were mainly involved in metabolic processes.A total of 4251 modified sites(4147 up-regulated,104 down-regulated)belonging to 1638 phosphoproteins(1555 up-regulated,83 down-regulated)were significantly changed in the liver.During hibernation,RPP regulated a diverse array of proteins involved in multiple functions,including metabolic enzymatic activity,ion transport,protein turnover,signal transduction,and alternative splicing.These changes contribute to enhancing protection,suppressing energy-consuming processes,and inducing metabolic depression.Moreover,the activities of phosphofructokinase,glutamate dehydrogenase,and ATPase were all significantly lower in winter compared to summer.In conclusion,our results support the hypothesis and demonstrate the importance of RPP as a regulatory mechanism when animals transition into a hypometabolic state.
基金financially supported by the National Natural Science Foundation of China(U2004104)the Natural Science Foundation of Henan Province(202300410080)+2 种基金the Key Project of Henan Education Committee(21A310005)the Internal Fund of Hebei University of Economics and Business(2020ZD10)the Postgraduate“Talent Program”of Henan University(SYL20060187 and SYL20060189)。
文摘In this study,we investigated the effects of major royal jelly proteins(MRJPs)on the estrogen,gut microbiota,and immunological responses in mice.Mice given 250 or 500 mg/kg,not 125 mg/kg of MRJPs,enhanced the proliferation of splenocytes in response to mitogens.The splenocytes and mesenteric lymphocytes activated by T-cell mitogens(Con A and anti-CD3/CD28 antibodies)released high levels of IL-2 but low levels of IFN-γand IL-17A.The release of IL-4 was unaffected by MRJPs.Additionally,splenocytes and mesenteric lymphocytes activated by LPS were prevented by MRJPs at the same dose as that required for producing IL-1βand IL-6,two pro-inflammatory cytokines.The production of IL-1β,IL-6,and IFN-γwas negatively associated with estrogen levels,which were higher in the MRJP-treated animals than in the control group.Analysis of the gut microbiota revealed that feeding mice 250 mg/kg of MRJPs maintained the stability of the natural intestinal microflora of mice.Additionally,the LEf Se analysis identified biomarkers in the MRJP-treated mice,including Prevotella,Bacillales,Enterobacteriales,Gammaproteobacteria,Candidatus_Arthromitus,and Shigella.Our results showed that MRJPs are important components of royal jelly that modulate host immunity and hormone levels and help maintain gut microbiota stability.
基金Supported by Tianjin Key Medical Discipline(Specialty)Construction Project(No.TJYXZDXK-037A).
文摘AIM:To explore the therapeutic effect and main molecular mechanisms of acteoside in a glaucoma model in DBA/2J mice.METHODS:Proteomics was used to compare the differentially expressed proteins of C57 and DBA/2J mice.After acteoside administration in DBA/2J mice,anterior segment observation,intraocular pressure(IOP)monitoring,electrophysiology examination,and hematoxylin and eosin staining were used to analyze any potential effects.Immunohistochemistry(IHC)assays were used to verify the proteomics results.Furthermore,retinal ganglion cell 5(RGC5)cell proliferation was assessed with cell counting kit-8(CCK-8)assays.Serta domain-containing protein 4(Sertad4)mRNA and protein expression levels were measured by qRT-PCR and Western blot analysis,respectively.RESULTS:Proteomics analysis suggested that Sertad4 was the most significantly differentially expressed protein.Compared with the saline group,the acteoside treatment group showed decreased IOP,improved N1-P1 wave amplitudes,thicker retina,and larger numbers of cells in the ganglion cell layer(GCL).The IHC results showed that Sertad4 expression levels in DBA/2J mice treated with acteoside were significantly lower than in the saline group.Acteoside treatment could improve RGC5 cell survival and reduce the Sertad4 mRNA and protein expression levels after glutamate injury.CONCLUSION:Sertad4 is differentially expressed in DBA/2J mice.Acteoside can protect RGCs from damage,possibly through the downregulation of Sertad4,and has a potential use in glaucoma treatment.
基金the National Natural Science Foundation of China(Nos.42061134020,32070380)the Natural Science Foundation of Shandong Province(No.ZR2019ZD17)。
文摘Light plays an important role in the photosynthesis and metabolic process of microalgae.However,how different light conditions regulate the biomass production and protein accumulation of microalgae is mostly unknown.In this study,the influence of different light conditions,including light colors,densities,and light:dark cycles on the cell growth and biochemical composition of Spirulina platensis was symmetrically characterized.Under different colored lights,S.platensis all shows an increase trend within the increased light intensity ranges;however,each showing different optimal light intensities.At the same light intensity,different colored lights show different growth rate of S.platensis following the sequence of red>white>green>yellow>blue.The maximum growth rate and protein accumulation were determined as 21.88 and 5.10 mg/(L·d)when illuminated under red LED.The energy efficiency of different light sources was calculated and ranked as red>white>blue≈green>yellow.Transcriptomic analysis suggests that red light can promote cell growth and protein accumulation by upregulating genes related to photosynthesis,carbon fixation,and C-N metabolism pathways.This study provides a conducive and efficient way to promote biomass production and protein accumulation of S.platensis by regulating light conditions.
基金Project supported by the National Key Research and Development Program of China(Grant No.2023YFF1204402)the National Natural Science Foundation of China(Grant Nos.12074079 and 12374208)+1 种基金the Natural Science Foundation of Shanghai(Grant No.22ZR1406800)the China Postdoctoral Science Foundation(Grant No.2022M720815).
文摘The rapid advancement and broad application of machine learning(ML)have driven a groundbreaking revolution in computational biology.One of the most cutting-edge and important applications of ML is its integration with molecular simulations to improve the sampling efficiency of the vast conformational space of large biomolecules.This review focuses on recent studies that utilize ML-based techniques in the exploration of protein conformational landscape.We first highlight the recent development of ML-aided enhanced sampling methods,including heuristic algorithms and neural networks that are designed to refine the selection of reaction coordinates for the construction of bias potential,or facilitate the exploration of the unsampled region of the energy landscape.Further,we review the development of autoencoder based methods that combine molecular simulations and deep learning to expand the search for protein conformations.Lastly,we discuss the cutting-edge methodologies for the one-shot generation of protein conformations with precise Boltzmann weights.Collectively,this review demonstrates the promising potential of machine learning in revolutionizing our insight into the complex conformational ensembles of proteins.
基金in part supported by the National Natural Science Foundation of China,Nos.30560042,81160161,81360198,and 82160255Education Department of Jiangxi Province,Nos.GJJ13198 and GJJ170021+1 种基金Jiangxi Provincial Department of Science and Technology,No.20192BAB205043Health and Family Planning Commission of Jiangxi Province,Nos.20181019 and 202210002(all to RX)。
文摘The onset of amyotrophic lateral sclerosis is usually characterized by focal death of both upper and/or lower motor neurons occurring in the motor cortex,basal ganglia,brainstem,and spinal cord,and commonly involves the muscles of the upper and/or lower extremities,and the muscles of the bulbar and/or respiratory regions.However,as the disease progresses,it affects the adjacent body regions,leading to generalized muscle weakness,occasionally along with memory,cognitive,behavioral,and language impairments;respiratory dysfunction occurs at the final stage of the disease.The disease has a complicated pathophysiology and currently,only riluzole,edaravone,and phenylbutyrate/taurursodiol are licensed to treat amyotrophic lateral sclerosis in many industrialized countries.The TAR DNA-binding protein 43 inclusions are observed in 97%of those diagnosed with amyotrophic lateral sclerosis.This review provides a preliminary overview of the potential effects of TAR DNAbinding protein 43 in the pathogenesis of amyotrophic lateral sclerosis,including the abnormalities in nucleoplasmic transport,RNA function,post-translational modification,liquid-liquid phase separation,stress granules,mitochondrial dysfunction,oxidative stress,axonal transport,protein quality control system,and non-cellular autonomous functions(e.g.,glial cell functions and prion-like propagation).
