AIM: Most studies on the immune effect of gp96 were focused on its enhancement of CTLs. It is interesting to know whether gp96 could influence the humoral immune response, and whether the recombinant N-terminal fragme...AIM: Most studies on the immune effect of gp96 were focused on its enhancement of CTLs. It is interesting to know whether gp96 could influence the humoral immune response, and whether the recombinant N-terminal fragment of gp96 could substitute native gp96 to stimulate the immune system.METHODS: gp96 isolated from livers of normal mice and its N-terminal fragment (amino acid 22-355) expressed in E coli were used for immunization of BALb/c mice. Eight groups of mice received one of the following regiments subcutaneously in 100 μL phosphate buffered saline (PBS)at an interval of 3 wk. Group 1: PBS only; group 2:gp96 only; group 3: N-terminal fragment only; group 4: HBsAg only; group 5: HBsAg+gp96; group 6: HBsAg+N-terminalfragment; group 7: HBsAg+incomplete Freud's adjuvant; group 8: HBsAg+N-terminal fragment (95 ℃ heated for 30 min). Serum anti-HBsAg antibody levels were assayed by ELISA. CTL responses in splenocytes were analyzed by ELISPOT after the last vaccination.RESULTS: The average titer of serum anti-HBsAg antibodyin the mice immunized with HBsAg together with gp96 or its N-terminal fragment were much higher than those immunized with HBsAg alone detected by ELISA. The cellular immune response of the mice immunized with HBsAg together with gp96 or its N-terminal fragment was not different with those immunized with HBsAg alone measured by ELISPOT assay.CONCLUSION: gp96 or its N-terminal fragment greatly improved humoral immune response induced by HBsAg, but failed to enhance the CTL response, which demonstrated the potential of using gp96 or its N-terminal fragment as a possible adjuvant to augment humoral immune response against HBV infection.展开更多
The amyloid beta precursor protein (APP) and its pathogenic byproduct β-amyloid peptide (Aβ) play central roles in the pathogenesis of Alzheimer’s disease (AD). Reduction in
Objective Biochemical indicators such as N-terminal pro-brain type natriuretic peptide(NT pro-BNP)and high-sensitivity Creactive protein(hsCRP)predict mortality in acute coronary syndrome(ACS).However,little is ...Objective Biochemical indicators such as N-terminal pro-brain type natriuretic peptide(NT pro-BNP)and high-sensitivity Creactive protein(hsCRP)predict mortality in acute coronary syndrome(ACS).However,little is known about the relationship of these factors with severity of coronary artery stenosis in patients with.Methods Three hundred and thirty-one subjects including 246 unstable angina pectoris patients and 85 myocardial infarction patients were recruited and classified into two groups:single-vessel disease group(1-vessel disease,n=93)and multiple-vessel disease group(≥2-vessels disease,n=238)according to selective coronary angiography.Plasma levels of NT pro-BNP and hsCRP were measured and severity of coronary stenosis was determined by Gensini score.Results NT pro-BNP but not hsCRP level was higher in patients with myocardial infarction than in patients with unstable angina pectoris.The patients with multiple-vessel disease had significantly higher NT pro-BNP level but not hsCRP compared with those with single-vessel disease.NT pro-BNP levels increased significantly as left ventricle(LV)function decreased,and only NT proBNP but not hsCRP level was related to Gensini score of severity of coronary stenosis in ACS.Conclusion NT proBNP but not hsCRP level is related to severity of coronary artery stenosis in patients in ACS.展开更多
Heavy metal ions in shellfish products are harmful to human health,and their removal with low nutrient loss remains challenging.Herein,a new type of mesoporous silica(SBA15),modified internally with ammonium pyrrolidi...Heavy metal ions in shellfish products are harmful to human health,and their removal with low nutrient loss remains challenging.Herein,a new type of mesoporous silica(SBA15),modified internally with ammonium pyrrolidine dithiocarbamate(APDC)and externally with alkyl-diol groups,which was named as Diol-APDC-SBA15,was successfully developed and characterized by powder X-ray diffraction patterns,nitrogen adsorption,and Fourier transform infrared spectroscopy.The solutions with lead,chromium,cadmium,and copper were used to investigate the adsorption capacity of Diol-APDC-SBA15.Diol-APDC-SBA15 was adopted to remove heavy metals from cooking liquids of clams(Ruditapes philippinarum),hydrolysate liquids of oysters(Ostrea gigas Thunberg),and polysaccharide solution from the cooking liquid of R.philippinarum.The efficiencies of removing heavy metal ions and the loss rates of proteins and polysaccharides were examined.The results showed that the adsorption capacities of Diol-APDCSBA15 for Pb,Cr,Cd,and Cu in standard heavy-metal solutions were 161.4,166.1,29.6,and 60.2mgg^(−1),respectively.The removal efficiency of Diol-APDC-SBA15 for Pb in the three shellfish processing liquids ranged from 60.5%to 99.6%.The Cr removal efficiency was above 99.9%in the oyster hydrolysate liquid.Meanwhile,the percentages of polysaccharide loss were 5.5%and 3.7%in the cooking liquid of clam and polysaccharide solution,respectively,and the protein loss was 1.2%in the oyster hydrolysate liquid.Therefore,the Diol-APDC-SBA15 material exhibits a great potential application in the removal of heavy metals from shellfish processing liquids with low losses of proteins and polysaccharides.展开更多
With the increasing per capita demand for animal protein,there is a growing interest in the abundant abalone protein resources.Abalone proteins are known for their nutritional and functional properties that contribute...With the increasing per capita demand for animal protein,there is a growing interest in the abundant abalone protein resources.Abalone proteins are known for their nutritional and functional properties that contribute to flavor and texture.We systematically constructed the relationship between abalone protein,processing,and proteomics.This paper reviews the nutritional properties of abalone proteins and evaluates the effects of different thermal processing techniques,non-thermal processing,and freezing on abalone proteins.In addition,we synthesize published abalone proteomics studies and the use of proteomics technology to better elucidate the quality changes of abalone and its products,and as a technical basis for the study of blue food marker proteins.It is important direction to clearly explain the protein composition and meat quality mechanism of abalone in the processing and storage by proteomic.During various types of thermal processing,non-thermal processing,and freezing of abalone,the various chemical forces between protein molecules are disrupted,which in turn leads to different degrees of denaturation,aggregation,and gelation,which may have an impact on the organoleptic properties,bioavailability,and digestibility of abalone muscle.Proteomics is used in abalone biology studies to understand developmental biology,physiology,disease,stress,and species identification and can also be a powerful tool to characterize processing methods on abalone quality properties.展开更多
Numerous strategies for linking desired chemical probes with target peptides and proteins have been developed and applied in the field of biological chemistry.Approaches for site-specific modification of native amino ...Numerous strategies for linking desired chemical probes with target peptides and proteins have been developed and applied in the field of biological chemistry.Approaches for site-specific modification of native amino acid residues in test tubes and biological contexts represent novel biological tools for understanding the role of peptides and proteins.Selective N-terminal modification strategies have been broadly studied especially in the last 10 years,as N-terminal positions are typically solvent exposed and provide chemically distinct sites for many peptide and protein targets,making N terminus distinct from other functional groups.A growing number of chemical and enzymatic techniques have been developed to modify N-terminal amino acids,and those techniques have the potential in the fields of medicine,basic research and applied materials science.This review focuses on appraising modification methodologies with the potential for biological applications from the past 10 years.展开更多
High molecular weight glutenin subunits(HMW-GS),major components of seed storage proteins in wheat,have large effects on processing quality.GLU-1 genes encode HMW-GS and their expression is mainly controlled at the tr...High molecular weight glutenin subunits(HMW-GS),major components of seed storage proteins in wheat,have large effects on processing quality.GLU-1 genes encode HMW-GS and their expression is mainly controlled at the transcriptional level by interactions between cis-regulatory elements and transcription factors.We previously identified an Aux/IAA transcription factor TaIAA10-6D that bound to a conserved cis-regulatory module CCRM1-1,the most essential conserved cis-regulatory module in GLU-1.Here,we confirmed the binding of TaIAA10-6D to CCRM1-1 using yeast one hybrid and dualluciferase reporter assays.The enhanced expression of TaIAA10-6D suppressed glutenin accumulation and increased gliadin content.Dynamic transcriptome analyses revealed that TaIAA10-6D overexpression down-regulated glutenin and gliadin genes during an early stage of grain filling,but up-regulated gliadin genes during a late stage probably by endoplasmic reticulum stress,accounting for its effect on the tradeoff between glutenin and gliadin.Rheological property and processing quality assays showed that TaIAA10-6D overproduction reduced stabilization time and bread quality,but enhanced cookie quality.Overexpression of TaIAA10-6D also reduced plant height,leaf size,kernel number and grain yield.We identified two major haplotypes of TaIAA10-6D,Hap I and Hap II,and developed a breeding-friendly diagnostic marker.Hap I conferred higher expression of TaIAA10-6D and concomitantly reduced plant height and kernel number,but had little effect on grain yield,contributing to lodging resistance without yield penalty.Hap I was subjected to positive selection in breeding.The findings provide a useful gene for wheat improvement and broaden insights into the regulatory machinery underpinning auxin-mediated quality formation,plant morphogenesis and yield gain.展开更多
In order to establish the sequence dependence of RimJ-mediated protein N-terminal acetylation in E. coli, the Z-domain variants differing by the second or third amino acid residue were expressed and analyzed by mass s...In order to establish the sequence dependence of RimJ-mediated protein N-terminal acetylation in E. coli, the Z-domain variants differing by the second or third amino acid residue were expressed and analyzed by mass spectrometry. Only subsequent to the initiating methionine residue cleavage, the RimJ-catalyzed N-terminal acetylation mainly occurred at the N-terminal serine and threonine residues and was significantly enhanced by hydrophobic or negatively charged residues in the penultimate position.展开更多
The profile of polypeptides separated by SDS-PAGE from seed of major crop species such as pea (Pisum sativum) is complex, resulting from cleavage (processing) of precursors expressed from multiple copies of genes enco...The profile of polypeptides separated by SDS-PAGE from seed of major crop species such as pea (Pisum sativum) is complex, resulting from cleavage (processing) of precursors expressed from multiple copies of genes encoding vicilin and legumin, the major storage globulins. Translation in vitro of mRNAs hybrid-selected from mid-maturation pea seed RNAs by denned vicilin and legumin cDNA clones provided precursor molecules that were cleaved in vitro by a cell-free protease extract obtained from similar stage seed; the derived polypep tides were of comparable sizes to those observed in vivo. The feasibility of transcribing mENA in vitro from a cDNA clone and cleavage in vitro of the derived translation products was established for a legumin clone, providing a method for determining polypeptide products of an expressed sequence. This approach will also be useful for characterising cleavage site requirements since modifications an readily be introduced at the DNA level.展开更多
Food allergens are mainly naturally-occurring proteins with immunoglobulin E(IgE)-binding epitopes.Understanding the structural and immunogenic characteristics of allergenic proteins is essential in assessing whether ...Food allergens are mainly naturally-occurring proteins with immunoglobulin E(IgE)-binding epitopes.Understanding the structural and immunogenic characteristics of allergenic proteins is essential in assessing whether and how food processing techniques reduce allergenicity.We here discuss the impacts of food processing technologies on the modification of physicochemical,structural,and immunogenic properties of allergenic proteins.Detection techniques for characterizing changes in these properties of food allergens are summarized.Food processing helps to reduce allergenicity by aggregating or denaturing proteins,which masks,modifies,or destroys antigenic epitopes,whereas,it cannot eliminate allergenicity completely,and sometimes even improves allergenicity by exposing new epitopes.Moreover,most food processing techniques have been tested on purified food allergens rather than food products due to potential interference of other food components.We provide guidance for further development of processing operations that can decrease the allergenicity of allergenic food proteins without negatively impacting the nutritional profile.展开更多
Proteolytic processing of the transmembrane amyloid precursor protein (APP) to aggregation-prone amyloid-β (Aβ) peptide underlies the development of Alzheimer’s disease.
Objective:To investigate the value of N-terminal pro B-type natriuretic peptide(NT-proBNP),high-sensitivity C-reactive protein(hs-CRP),and homocysteine(Hcy)levels in predicting cardiovascular events(CV)in patients wit...Objective:To investigate the value of N-terminal pro B-type natriuretic peptide(NT-proBNP),high-sensitivity C-reactive protein(hs-CRP),and homocysteine(Hcy)levels in predicting cardiovascular events(CV)in patients with chronic heart failure(CHF).Methods:A total of 63 patients with CHF admitted to our hospital between June 2019 and July 2021 were selected.Their NT-proBNP,hs-CRP,and Hcy levels were detected at discharge,and a 12-month follow-up was done after their discharge to collect clinical data.The collected data were inclusive of data from 21 CHF patients with cardiovascular disease and 42 CHF patients without cardiovascular disease.The effect of NT-proBNP,hs-CRP,and Hcy levels on the occurrence of CV was analyzed.Results:The levels of NT-proBNP,hs-CRP,and Hcy in the group with cardiovascular disease were significantly higher than those in the group without cardiovascular disease(P<0.05);the levels of serum NT-proBNP,hs-CRP,and Hcy at discharge had certain value in predicting short-term CV in CHF patients(P<0.05).Conclusion:NT-proBNP,hs-CRP,and Hcy levels can be used to predict CV in CHF patients,thus having clinical application value.展开更多
The methylotrophic yeast Pichia pastoris is a highly successful system for production of a variety of heterologous proteins due to its unique features/abilities for effective protein expression, and tremendous efforts...The methylotrophic yeast Pichia pastoris is a highly successful system for production of a variety of heterologous proteins due to its unique features/abilities for effective protein expression, and tremendous efforts have been made to increase heterologous protein productivity by P. pastoris in recent years. When new engineered yeast strains are constructed and are ready to use tot industrial protein production, process control and optimization techniques should be applied to improve the fermentation performance in the following aspects: (1) increase recombinant cell concentrations in fermentor to high density during growth phase; (2) effectively induce heterologous proteins by enhancing/stabilizing titers or concentrations of the proteins during induction phase; (3) decrease operation costs by relieving the working loads of heat-exchange and oxygen supply. This article reviews and discusses the key and commonly used techniques in heterologous protein production by P. pastoris, with the focus on optimizations of fermentation media and basic operation conditions, development of optimal glycerol feeding strategies for achieving high density cultivation of P. pastoris and effective heterologous protein induction methods by regulating specific growth rate, methanol concentration, temperatures, mixture ratio of multi-carbon substrates, etc. Metabolic analysis for recombinant protein production by P. pastoris is also introduced to interpret the mechanism of sub-optimal heterologous protein production and to explore further optimal expression methods.展开更多
MicroRNAs (miRNAs) post-transcriptionally regulate gene expression by binding to target mRNAs with perfect or imperfect complementarity, recruiting an Argonaute (AGO) protein complex that usually results in degrad...MicroRNAs (miRNAs) post-transcriptionally regulate gene expression by binding to target mRNAs with perfect or imperfect complementarity, recruiting an Argonaute (AGO) protein complex that usually results in degradation or translational repression of the target mRNA. AGO proteins function as the Slicer enzyme in miRNA and small interfering RNA (siRNA) pathways involved in human physiological and pathophysiological processes, such as antiviral responses and disease formation. Although the past decade has witnessed rapid advancement in studies of AGO protein functions, to further elucidate the molecular mechanism of AGO proteins in cellular function and biochemical process is really a challenging area for researchers. In order to understand the molecular causes underlying the pathological processes, we mainly focus on five fundamental problems of AGO proteins, including evolution, functional domain, subcellular location, post-translational modification and protein-protein interactions. Our discussion highlight their roles in early diagnosis, disease prevention, drug target identification, drug response, etc.展开更多
Lentil is a highly nutritious legume with an ample quantity of carbohydrates and good amount of proteins, minerals, vitamins, phytochemicals and fibres. Although it has been used as staple food since ancient times, it...Lentil is a highly nutritious legume with an ample quantity of carbohydrates and good amount of proteins, minerals, vitamins, phytochemicals and fibres. Although it has been used as staple food since ancient times, its usage has been limited in developed countries, especially due to the lower protein digestibility, presence of anti-nutritional factors, flatulence and poor cooking qualities. Processing of lentils including dehulling and splitting and isolation of major fractions, e.g., proteins and starches are some of the strategies that can be adopted to add value and increase consumption of these legumes. This review paper intends to provide detailed overview of lentil's global production, nutritional composition and processing methods of lentil. Methods of isolation/characterization of lentil protein and starch and their subsequent application in foods are also presented.展开更多
Protein powders from Eisenia foetida were prepared using different drying processes and fractionation. Differential scanning calorimetry was used to show that heat denaturation occurred during the drying process above...Protein powders from Eisenia foetida were prepared using different drying processes and fractionation. Differential scanning calorimetry was used to show that heat denaturation occurred during the drying process above 42°C. Protein solubility was also studied. The addition of dissociating reagents allowed concluding that solubility was decreased during oven drying due to thermo denaturation including hydrogen bonds. The volatile compounds of the different powders were extracted by solid phase micro-extraction and identified by mass spectrometry. Volatile compounds were related to lipid oxidation and Maillard reactions occurring during the preparation of the powders. High drying temperatures led to more volatile compounds resulting from Maillard reactions. In the protein powder preparation process, a fractionation step led to a “pulp fraction” and a “juice fraction” of earthworms. The “pulp fraction” contained less odorant volatile compounds resulting from Maillard reactions than the “juice fraction” did.展开更多
Background: During processing in a desolventizer/toaster(DT), rapeseed meal(RSM) is heated to evaporate the hexane and to reduce the level of heat-labile anti-nutritional factors such as glucosinolates(GSL). Ho...Background: During processing in a desolventizer/toaster(DT), rapeseed meal(RSM) is heated to evaporate the hexane and to reduce the level of heat-labile anti-nutritional factors such as glucosinolates(GSL). However, excessive heat treatment may reduce amino acid(AA) content in addition to lower AA digestibility and availability in RSM. The objective of the present study was to produce from one batch of a 00-rapeseed variety(17 μmol GSL/g dry matter(DM), seed grade quality) five differently processed RSM under standardized and defined conditions in a pilot plant,and to determine the impact of these different treatments on protein solubility and chemical composition, in particular with regard to contents of AA including reactive Lys(rL ys) and levels of total and individual GSL.Methods: Four RSM were exposed to wet toasting conditions(WetT C) with increasing residence time in the DT of 48,64, 76, and 93 min. A blend of these four RSM was further processed, starting with saturated steam processing(〈 100 °C)and followed by exposure to dry toasting conditions(DryT C) to further reduce the GSL content in this RSM.Results: The contents of neutral detergent fiber and neutral detergent fiber bound crude protein(CP) increased linearly(P 〈 0.05), as residence time of RSM in the DT increased from 48 to 93 min, whereas contents of total and most individual GSL and those of Lys, rL ys, Cys, and the calculated ratio of Lys:CP and r Lys:CP decreased linearly(P ≤ 0.05).The combination of wet heating and DryT C resulted in the lowest GSL content compared to RSM produced under WetT C, but was associated with lowest protein solubility.Conclusions: It can be concluded that by increasing residence time in the DT or using alternative processing conditions such as wet heating combined with DryT C, contents of total and individual GSL in RSM can be substantially reduced.Further in vivo studies are warranted to elucidate if and to which extent the observed differences in protein quality and GSL content between RSM may affect digestibility and bioavailability of AA in monogastric animals.展开更多
AIM:To investigate the role of c-Jun N-terminal kinase(JNK) in thermotherapy-induced apoptosis in human gastric cancer SGC-7901 cells.METHODS:Human gastric cancer SGC-7901 cells were cultured in vitro.Following thermo...AIM:To investigate the role of c-Jun N-terminal kinase(JNK) in thermotherapy-induced apoptosis in human gastric cancer SGC-7901 cells.METHODS:Human gastric cancer SGC-7901 cells were cultured in vitro.Following thermotherapy at 43 ℃ for 0,0.5,1,2 or 3 h,the cells were cultured for a further 24 h with or without the JNK specific inhibitor,SP600125 for 2 h.Apoptosis was evaluated by immunohistochemistry [terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL)] and flow cytometry(Annexin vs propidium iodide).Cell proliferation was determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide.The production of p-JNK,Bcl-2,Bax and caspase-3 proteins was evaluated by Western blotting.The expression of JNK at mRNA level was determined by reverse transcription polymerase chain reaction.RESULTS:The proliferation of gastric carcinoma SGC-7901 cells was significantly inhibited following thermotherapy,and was 32.7%,30.6%,43.8% and 52.9% at 0.5,1,2 and 3 h post-thermotherapy,respectively.Flow cytometry analysis revealed an increased population of SGC790l cells in G0/G1 phase,but a reduced population in S phase following thermotherapy for 1 or 2 h,compared to untreated cells(P < 0.05).The increased number of SGC-790l cells in G0/G1 phase was consistent with induced apoptosis(flow cytometry) following thermotherapy for 0.5,1,2 or 3 h,compared to the untreated group(46.5% ± 0.23%,39.9% ± 0.53%,56.6% ± 0.35% and 50.4% ± 0.29% vs 7.3% ± 0.10%,P < 0.01),respectively.This was supported by the TUNEL assay(48.2% ± 0.4%,40.1% ± 0.2%,61.2% ± 0.29% and 52.0% ± 0.42% vs 12.2% ± 0.22%,P < 0.01) respectively.More importantly,the expression of p-JNK protein and JNK mRNA levels were significantly higher at 0.5 h than at 0 h post-treatment(P < 0.01),and peaked at 2 h.A similar pattern was detected for Bax and caspase-3 proteins.Bcl-2 increased at 0.5 h,peaked at 1 h,and then decreased.Furthermore,the JNK specific inhibitor,SP600125,suppressed p-JNK,Bax and caspase-3 at the protein level in SGC790l cells following thermotherapy,compared to mock-inhibitor treatment,which was in line with the decreased rate of apoptosis.The expression of Bcl-2 was consistent with thermotherapy alone.CONCLUSION:Thermotherapy induced apoptosis in gastric cancer cells by promoting p-JNK at the mRNA and protein levels,and up-regulated the expression of Bax and caspase-3 proteins.Bcl-2 may play a protective role during thermotherapy.Activation of JNK via the Bax-caspase-3 pathway may be important in thermotherapy-induced apoptosis in gastric cancer cells.展开更多
Cronobacter sakazakii is an emerging pathogen that can cause diseases for several infant groups. These bacteria were contaminated in foods, clinical utensils, and environments. In Indonesia, C. sakazakii has been isol...Cronobacter sakazakii is an emerging pathogen that can cause diseases for several infant groups. These bacteria were contaminated in foods, clinical utensils, and environments. In Indonesia, C. sakazakii has been isolated from powdered infant formulas, weaning foods, and other dried foods such as cornstarch. The objective of this research is to trace survival of C. sakazakii during cornstarch production step using its mutant. Mutant was constructed by inserting Green Fluorescent Protein plasmid inside to the bacterial cell that appeared green fluorescent colonies under UV observation. The presence of C. sakazakii during processing was conducted by artificial contamination. This research consists of three steps, i.e. determination of the suitable enumeration method of C. sakazakii’s mutant, cornstarch production from yellow corn, and survival analysis of C. sakazakii during endosperm soaking and cornstarch drying. The suitable enumeration method was surface plating method on TSA-ampicillin medium combining with UV light application because of ineffectiveness of ampicillin inhibition for growth of yeasts and molds. The cornstarch produced in laboratory has the same properties with commercial cornstarch in parameters of moisture content, density, and starch granule structure. The yield of cornstarch final product was 48.90% (dry whole kernel-based). C. sakazakii cannot survive in 48 hours soaking process at 52?C and 24 hours drying process at 50?C that is applied during cornstarch production.展开更多
基金Supported by the Major State Basic Research Development Program of China, Program 973, Grant No. 2001CB510001
文摘AIM: Most studies on the immune effect of gp96 were focused on its enhancement of CTLs. It is interesting to know whether gp96 could influence the humoral immune response, and whether the recombinant N-terminal fragment of gp96 could substitute native gp96 to stimulate the immune system.METHODS: gp96 isolated from livers of normal mice and its N-terminal fragment (amino acid 22-355) expressed in E coli were used for immunization of BALb/c mice. Eight groups of mice received one of the following regiments subcutaneously in 100 μL phosphate buffered saline (PBS)at an interval of 3 wk. Group 1: PBS only; group 2:gp96 only; group 3: N-terminal fragment only; group 4: HBsAg only; group 5: HBsAg+gp96; group 6: HBsAg+N-terminalfragment; group 7: HBsAg+incomplete Freud's adjuvant; group 8: HBsAg+N-terminal fragment (95 ℃ heated for 30 min). Serum anti-HBsAg antibody levels were assayed by ELISA. CTL responses in splenocytes were analyzed by ELISPOT after the last vaccination.RESULTS: The average titer of serum anti-HBsAg antibodyin the mice immunized with HBsAg together with gp96 or its N-terminal fragment were much higher than those immunized with HBsAg alone detected by ELISA. The cellular immune response of the mice immunized with HBsAg together with gp96 or its N-terminal fragment was not different with those immunized with HBsAg alone measured by ELISPOT assay.CONCLUSION: gp96 or its N-terminal fragment greatly improved humoral immune response induced by HBsAg, but failed to enhance the CTL response, which demonstrated the potential of using gp96 or its N-terminal fragment as a possible adjuvant to augment humoral immune response against HBV infection.
文摘The amyloid beta precursor protein (APP) and its pathogenic byproduct β-amyloid peptide (Aβ) play central roles in the pathogenesis of Alzheimer’s disease (AD). Reduction in
文摘Objective Biochemical indicators such as N-terminal pro-brain type natriuretic peptide(NT pro-BNP)and high-sensitivity Creactive protein(hsCRP)predict mortality in acute coronary syndrome(ACS).However,little is known about the relationship of these factors with severity of coronary artery stenosis in patients with.Methods Three hundred and thirty-one subjects including 246 unstable angina pectoris patients and 85 myocardial infarction patients were recruited and classified into two groups:single-vessel disease group(1-vessel disease,n=93)and multiple-vessel disease group(≥2-vessels disease,n=238)according to selective coronary angiography.Plasma levels of NT pro-BNP and hsCRP were measured and severity of coronary stenosis was determined by Gensini score.Results NT pro-BNP but not hsCRP level was higher in patients with myocardial infarction than in patients with unstable angina pectoris.The patients with multiple-vessel disease had significantly higher NT pro-BNP level but not hsCRP compared with those with single-vessel disease.NT pro-BNP levels increased significantly as left ventricle(LV)function decreased,and only NT proBNP but not hsCRP level was related to Gensini score of severity of coronary stenosis in ACS.Conclusion NT proBNP but not hsCRP level is related to severity of coronary artery stenosis in patients in ACS.
基金supported by the National Key R&D Program of China(No.2018YFD0901004)the National Natural Science Foundation of China(No.31601538)+2 种基金the Key Science and Technology Program of Liaoning Province(No.2020JH1/10200001)the Fundamental Research Foundation of Education Department of Liaoning Province(No.JL202008)the Science&Technology Innovation Foundation of Dalian(No.2019J12SN61).
文摘Heavy metal ions in shellfish products are harmful to human health,and their removal with low nutrient loss remains challenging.Herein,a new type of mesoporous silica(SBA15),modified internally with ammonium pyrrolidine dithiocarbamate(APDC)and externally with alkyl-diol groups,which was named as Diol-APDC-SBA15,was successfully developed and characterized by powder X-ray diffraction patterns,nitrogen adsorption,and Fourier transform infrared spectroscopy.The solutions with lead,chromium,cadmium,and copper were used to investigate the adsorption capacity of Diol-APDC-SBA15.Diol-APDC-SBA15 was adopted to remove heavy metals from cooking liquids of clams(Ruditapes philippinarum),hydrolysate liquids of oysters(Ostrea gigas Thunberg),and polysaccharide solution from the cooking liquid of R.philippinarum.The efficiencies of removing heavy metal ions and the loss rates of proteins and polysaccharides were examined.The results showed that the adsorption capacities of Diol-APDCSBA15 for Pb,Cr,Cd,and Cu in standard heavy-metal solutions were 161.4,166.1,29.6,and 60.2mgg^(−1),respectively.The removal efficiency of Diol-APDC-SBA15 for Pb in the three shellfish processing liquids ranged from 60.5%to 99.6%.The Cr removal efficiency was above 99.9%in the oyster hydrolysate liquid.Meanwhile,the percentages of polysaccharide loss were 5.5%and 3.7%in the cooking liquid of clam and polysaccharide solution,respectively,and the protein loss was 1.2%in the oyster hydrolysate liquid.Therefore,the Diol-APDC-SBA15 material exhibits a great potential application in the removal of heavy metals from shellfish processing liquids with low losses of proteins and polysaccharides.
基金supported by the Cross-disciplinary Integration Project of Fujian Agriculture and Forestry University(71202103C)Science and Technology Projects of Fuzhou Ocean Research Institute(2022F16).
文摘With the increasing per capita demand for animal protein,there is a growing interest in the abundant abalone protein resources.Abalone proteins are known for their nutritional and functional properties that contribute to flavor and texture.We systematically constructed the relationship between abalone protein,processing,and proteomics.This paper reviews the nutritional properties of abalone proteins and evaluates the effects of different thermal processing techniques,non-thermal processing,and freezing on abalone proteins.In addition,we synthesize published abalone proteomics studies and the use of proteomics technology to better elucidate the quality changes of abalone and its products,and as a technical basis for the study of blue food marker proteins.It is important direction to clearly explain the protein composition and meat quality mechanism of abalone in the processing and storage by proteomic.During various types of thermal processing,non-thermal processing,and freezing of abalone,the various chemical forces between protein molecules are disrupted,which in turn leads to different degrees of denaturation,aggregation,and gelation,which may have an impact on the organoleptic properties,bioavailability,and digestibility of abalone muscle.Proteomics is used in abalone biology studies to understand developmental biology,physiology,disease,stress,and species identification and can also be a powerful tool to characterize processing methods on abalone quality properties.
基金supported by Shandong Provincial Natural Science Foundation,China(No.ZR2020QC081,H.Jiang)Youth Innovation Team Talent Introduction Program of Shandong Province(No.20190164,R.Zhang and H.Jiang)。
文摘Numerous strategies for linking desired chemical probes with target peptides and proteins have been developed and applied in the field of biological chemistry.Approaches for site-specific modification of native amino acid residues in test tubes and biological contexts represent novel biological tools for understanding the role of peptides and proteins.Selective N-terminal modification strategies have been broadly studied especially in the last 10 years,as N-terminal positions are typically solvent exposed and provide chemically distinct sites for many peptide and protein targets,making N terminus distinct from other functional groups.A growing number of chemical and enzymatic techniques have been developed to modify N-terminal amino acids,and those techniques have the potential in the fields of medicine,basic research and applied materials science.This review focuses on appraising modification methodologies with the potential for biological applications from the past 10 years.
基金supported by the STI 2030-Major Projects(2023ZD0406903)the National Natural and Science Foundation of China(32272182)+1 种基金the Postdoctoral Fellowship Program of CPSF(GZC20241955)the Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(CAAS).
文摘High molecular weight glutenin subunits(HMW-GS),major components of seed storage proteins in wheat,have large effects on processing quality.GLU-1 genes encode HMW-GS and their expression is mainly controlled at the transcriptional level by interactions between cis-regulatory elements and transcription factors.We previously identified an Aux/IAA transcription factor TaIAA10-6D that bound to a conserved cis-regulatory module CCRM1-1,the most essential conserved cis-regulatory module in GLU-1.Here,we confirmed the binding of TaIAA10-6D to CCRM1-1 using yeast one hybrid and dualluciferase reporter assays.The enhanced expression of TaIAA10-6D suppressed glutenin accumulation and increased gliadin content.Dynamic transcriptome analyses revealed that TaIAA10-6D overexpression down-regulated glutenin and gliadin genes during an early stage of grain filling,but up-regulated gliadin genes during a late stage probably by endoplasmic reticulum stress,accounting for its effect on the tradeoff between glutenin and gliadin.Rheological property and processing quality assays showed that TaIAA10-6D overproduction reduced stabilization time and bread quality,but enhanced cookie quality.Overexpression of TaIAA10-6D also reduced plant height,leaf size,kernel number and grain yield.We identified two major haplotypes of TaIAA10-6D,Hap I and Hap II,and developed a breeding-friendly diagnostic marker.Hap I conferred higher expression of TaIAA10-6D and concomitantly reduced plant height and kernel number,but had little effect on grain yield,contributing to lodging resistance without yield penalty.Hap I was subjected to positive selection in breeding.The findings provide a useful gene for wheat improvement and broaden insights into the regulatory machinery underpinning auxin-mediated quality formation,plant morphogenesis and yield gain.
文摘In order to establish the sequence dependence of RimJ-mediated protein N-terminal acetylation in E. coli, the Z-domain variants differing by the second or third amino acid residue were expressed and analyzed by mass spectrometry. Only subsequent to the initiating methionine residue cleavage, the RimJ-catalyzed N-terminal acetylation mainly occurred at the N-terminal serine and threonine residues and was significantly enhanced by hydrophobic or negatively charged residues in the penultimate position.
文摘The profile of polypeptides separated by SDS-PAGE from seed of major crop species such as pea (Pisum sativum) is complex, resulting from cleavage (processing) of precursors expressed from multiple copies of genes encoding vicilin and legumin, the major storage globulins. Translation in vitro of mRNAs hybrid-selected from mid-maturation pea seed RNAs by denned vicilin and legumin cDNA clones provided precursor molecules that were cleaved in vitro by a cell-free protease extract obtained from similar stage seed; the derived polypep tides were of comparable sizes to those observed in vivo. The feasibility of transcribing mENA in vitro from a cDNA clone and cleavage in vitro of the derived translation products was established for a legumin clone, providing a method for determining polypeptide products of an expressed sequence. This approach will also be useful for characterising cleavage site requirements since modifications an readily be introduced at the DNA level.
基金supported by the National Natural Science Foundation of China (32102605)the Agricultural Science and Technology Innovation Program under Grant (CAAS-ASTIP-2020IAR)the Earmarked Fund for CARS (CARS-44)。
文摘Food allergens are mainly naturally-occurring proteins with immunoglobulin E(IgE)-binding epitopes.Understanding the structural and immunogenic characteristics of allergenic proteins is essential in assessing whether and how food processing techniques reduce allergenicity.We here discuss the impacts of food processing technologies on the modification of physicochemical,structural,and immunogenic properties of allergenic proteins.Detection techniques for characterizing changes in these properties of food allergens are summarized.Food processing helps to reduce allergenicity by aggregating or denaturing proteins,which masks,modifies,or destroys antigenic epitopes,whereas,it cannot eliminate allergenicity completely,and sometimes even improves allergenicity by exposing new epitopes.Moreover,most food processing techniques have been tested on purified food allergens rather than food products due to potential interference of other food components.We provide guidance for further development of processing operations that can decrease the allergenicity of allergenic food proteins without negatively impacting the nutritional profile.
文摘Proteolytic processing of the transmembrane amyloid precursor protein (APP) to aggregation-prone amyloid-β (Aβ) peptide underlies the development of Alzheimer’s disease.
基金supported by the Project of Baoding Science and Technology Bureau(Project number:2241ZF343).
文摘Objective:To investigate the value of N-terminal pro B-type natriuretic peptide(NT-proBNP),high-sensitivity C-reactive protein(hs-CRP),and homocysteine(Hcy)levels in predicting cardiovascular events(CV)in patients with chronic heart failure(CHF).Methods:A total of 63 patients with CHF admitted to our hospital between June 2019 and July 2021 were selected.Their NT-proBNP,hs-CRP,and Hcy levels were detected at discharge,and a 12-month follow-up was done after their discharge to collect clinical data.The collected data were inclusive of data from 21 CHF patients with cardiovascular disease and 42 CHF patients without cardiovascular disease.The effect of NT-proBNP,hs-CRP,and Hcy levels on the occurrence of CV was analyzed.Results:The levels of NT-proBNP,hs-CRP,and Hcy in the group with cardiovascular disease were significantly higher than those in the group without cardiovascular disease(P<0.05);the levels of serum NT-proBNP,hs-CRP,and Hcy at discharge had certain value in predicting short-term CV in CHF patients(P<0.05).Conclusion:NT-proBNP,hs-CRP,and Hcy levels can be used to predict CV in CHF patients,thus having clinical application value.
基金Supported by the Key Agricultral Technology Program of Shanghai Science & Technology Committee(073919108)MajorState Basic Research Development Program of China(2007CB714303)
文摘The methylotrophic yeast Pichia pastoris is a highly successful system for production of a variety of heterologous proteins due to its unique features/abilities for effective protein expression, and tremendous efforts have been made to increase heterologous protein productivity by P. pastoris in recent years. When new engineered yeast strains are constructed and are ready to use tot industrial protein production, process control and optimization techniques should be applied to improve the fermentation performance in the following aspects: (1) increase recombinant cell concentrations in fermentor to high density during growth phase; (2) effectively induce heterologous proteins by enhancing/stabilizing titers or concentrations of the proteins during induction phase; (3) decrease operation costs by relieving the working loads of heat-exchange and oxygen supply. This article reviews and discusses the key and commonly used techniques in heterologous protein production by P. pastoris, with the focus on optimizations of fermentation media and basic operation conditions, development of optimal glycerol feeding strategies for achieving high density cultivation of P. pastoris and effective heterologous protein induction methods by regulating specific growth rate, methanol concentration, temperatures, mixture ratio of multi-carbon substrates, etc. Metabolic analysis for recombinant protein production by P. pastoris is also introduced to interpret the mechanism of sub-optimal heterologous protein production and to explore further optimal expression methods.
文摘MicroRNAs (miRNAs) post-transcriptionally regulate gene expression by binding to target mRNAs with perfect or imperfect complementarity, recruiting an Argonaute (AGO) protein complex that usually results in degradation or translational repression of the target mRNA. AGO proteins function as the Slicer enzyme in miRNA and small interfering RNA (siRNA) pathways involved in human physiological and pathophysiological processes, such as antiviral responses and disease formation. Although the past decade has witnessed rapid advancement in studies of AGO protein functions, to further elucidate the molecular mechanism of AGO proteins in cellular function and biochemical process is really a challenging area for researchers. In order to understand the molecular causes underlying the pathological processes, we mainly focus on five fundamental problems of AGO proteins, including evolution, functional domain, subcellular location, post-translational modification and protein-protein interactions. Our discussion highlight their roles in early diagnosis, disease prevention, drug target identification, drug response, etc.
文摘Lentil is a highly nutritious legume with an ample quantity of carbohydrates and good amount of proteins, minerals, vitamins, phytochemicals and fibres. Although it has been used as staple food since ancient times, its usage has been limited in developed countries, especially due to the lower protein digestibility, presence of anti-nutritional factors, flatulence and poor cooking qualities. Processing of lentils including dehulling and splitting and isolation of major fractions, e.g., proteins and starches are some of the strategies that can be adopted to add value and increase consumption of these legumes. This review paper intends to provide detailed overview of lentil's global production, nutritional composition and processing methods of lentil. Methods of isolation/characterization of lentil protein and starch and their subsequent application in foods are also presented.
文摘Protein powders from Eisenia foetida were prepared using different drying processes and fractionation. Differential scanning calorimetry was used to show that heat denaturation occurred during the drying process above 42°C. Protein solubility was also studied. The addition of dissociating reagents allowed concluding that solubility was decreased during oven drying due to thermo denaturation including hydrogen bonds. The volatile compounds of the different powders were extracted by solid phase micro-extraction and identified by mass spectrometry. Volatile compounds were related to lipid oxidation and Maillard reactions occurring during the preparation of the powders. High drying temperatures led to more volatile compounds resulting from Maillard reactions. In the protein powder preparation process, a fractionation step led to a “pulp fraction” and a “juice fraction” of earthworms. The “pulp fraction” contained less odorant volatile compounds resulting from Maillard reactions than the “juice fraction” did.
文摘Background: During processing in a desolventizer/toaster(DT), rapeseed meal(RSM) is heated to evaporate the hexane and to reduce the level of heat-labile anti-nutritional factors such as glucosinolates(GSL). However, excessive heat treatment may reduce amino acid(AA) content in addition to lower AA digestibility and availability in RSM. The objective of the present study was to produce from one batch of a 00-rapeseed variety(17 μmol GSL/g dry matter(DM), seed grade quality) five differently processed RSM under standardized and defined conditions in a pilot plant,and to determine the impact of these different treatments on protein solubility and chemical composition, in particular with regard to contents of AA including reactive Lys(rL ys) and levels of total and individual GSL.Methods: Four RSM were exposed to wet toasting conditions(WetT C) with increasing residence time in the DT of 48,64, 76, and 93 min. A blend of these four RSM was further processed, starting with saturated steam processing(〈 100 °C)and followed by exposure to dry toasting conditions(DryT C) to further reduce the GSL content in this RSM.Results: The contents of neutral detergent fiber and neutral detergent fiber bound crude protein(CP) increased linearly(P 〈 0.05), as residence time of RSM in the DT increased from 48 to 93 min, whereas contents of total and most individual GSL and those of Lys, rL ys, Cys, and the calculated ratio of Lys:CP and r Lys:CP decreased linearly(P ≤ 0.05).The combination of wet heating and DryT C resulted in the lowest GSL content compared to RSM produced under WetT C, but was associated with lowest protein solubility.Conclusions: It can be concluded that by increasing residence time in the DT or using alternative processing conditions such as wet heating combined with DryT C, contents of total and individual GSL in RSM can be substantially reduced.Further in vivo studies are warranted to elucidate if and to which extent the observed differences in protein quality and GSL content between RSM may affect digestibility and bioavailability of AA in monogastric animals.
基金Supported by A grant from the National Eleventh Five-Year Technology Support Project of China,No. 2008 BAI68B01
文摘AIM:To investigate the role of c-Jun N-terminal kinase(JNK) in thermotherapy-induced apoptosis in human gastric cancer SGC-7901 cells.METHODS:Human gastric cancer SGC-7901 cells were cultured in vitro.Following thermotherapy at 43 ℃ for 0,0.5,1,2 or 3 h,the cells were cultured for a further 24 h with or without the JNK specific inhibitor,SP600125 for 2 h.Apoptosis was evaluated by immunohistochemistry [terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL)] and flow cytometry(Annexin vs propidium iodide).Cell proliferation was determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide.The production of p-JNK,Bcl-2,Bax and caspase-3 proteins was evaluated by Western blotting.The expression of JNK at mRNA level was determined by reverse transcription polymerase chain reaction.RESULTS:The proliferation of gastric carcinoma SGC-7901 cells was significantly inhibited following thermotherapy,and was 32.7%,30.6%,43.8% and 52.9% at 0.5,1,2 and 3 h post-thermotherapy,respectively.Flow cytometry analysis revealed an increased population of SGC790l cells in G0/G1 phase,but a reduced population in S phase following thermotherapy for 1 or 2 h,compared to untreated cells(P < 0.05).The increased number of SGC-790l cells in G0/G1 phase was consistent with induced apoptosis(flow cytometry) following thermotherapy for 0.5,1,2 or 3 h,compared to the untreated group(46.5% ± 0.23%,39.9% ± 0.53%,56.6% ± 0.35% and 50.4% ± 0.29% vs 7.3% ± 0.10%,P < 0.01),respectively.This was supported by the TUNEL assay(48.2% ± 0.4%,40.1% ± 0.2%,61.2% ± 0.29% and 52.0% ± 0.42% vs 12.2% ± 0.22%,P < 0.01) respectively.More importantly,the expression of p-JNK protein and JNK mRNA levels were significantly higher at 0.5 h than at 0 h post-treatment(P < 0.01),and peaked at 2 h.A similar pattern was detected for Bax and caspase-3 proteins.Bcl-2 increased at 0.5 h,peaked at 1 h,and then decreased.Furthermore,the JNK specific inhibitor,SP600125,suppressed p-JNK,Bax and caspase-3 at the protein level in SGC790l cells following thermotherapy,compared to mock-inhibitor treatment,which was in line with the decreased rate of apoptosis.The expression of Bcl-2 was consistent with thermotherapy alone.CONCLUSION:Thermotherapy induced apoptosis in gastric cancer cells by promoting p-JNK at the mRNA and protein levels,and up-regulated the expression of Bax and caspase-3 proteins.Bcl-2 may play a protective role during thermotherapy.Activation of JNK via the Bax-caspase-3 pathway may be important in thermotherapy-induced apoptosis in gastric cancer cells.
文摘Cronobacter sakazakii is an emerging pathogen that can cause diseases for several infant groups. These bacteria were contaminated in foods, clinical utensils, and environments. In Indonesia, C. sakazakii has been isolated from powdered infant formulas, weaning foods, and other dried foods such as cornstarch. The objective of this research is to trace survival of C. sakazakii during cornstarch production step using its mutant. Mutant was constructed by inserting Green Fluorescent Protein plasmid inside to the bacterial cell that appeared green fluorescent colonies under UV observation. The presence of C. sakazakii during processing was conducted by artificial contamination. This research consists of three steps, i.e. determination of the suitable enumeration method of C. sakazakii’s mutant, cornstarch production from yellow corn, and survival analysis of C. sakazakii during endosperm soaking and cornstarch drying. The suitable enumeration method was surface plating method on TSA-ampicillin medium combining with UV light application because of ineffectiveness of ampicillin inhibition for growth of yeasts and molds. The cornstarch produced in laboratory has the same properties with commercial cornstarch in parameters of moisture content, density, and starch granule structure. The yield of cornstarch final product was 48.90% (dry whole kernel-based). C. sakazakii cannot survive in 48 hours soaking process at 52?C and 24 hours drying process at 50?C that is applied during cornstarch production.