Background: Lysine is used widely in livestock production due to the shortage of feed protein resources.Llysine·H2SO4 contains L-lysine sulphate as well as fermentation co-products which contain other amino acids...Background: Lysine is used widely in livestock production due to the shortage of feed protein resources.Llysine·H2SO4 contains L-lysine sulphate as well as fermentation co-products which contain other amino acids and phosphorus.However,there are few articles about L-lysine·H2SO4 product regarding intestinal morphology and liver pathology of broiler chickens.In this article,we focus on the absorption and metabolism of L-lysine·H2SO4 revealed in the variation of intestinal morphology and liver pathology to determine the tolerance of chicks for L-lysine·H2SO4.Methods: To evaluate the tolerance of broilers for L-lysine·H2SO4,240 one day old broilers were allocated randomly to one of five dietary treatments which included corn-soybean diets containing 0,1%,4%,7% or 10% L-lysine·H2SO4(L-lysine content = 55%).Results: Supplementation of 1% L-lysine·H2SO4 in the diet had no negative effects.However,4%,7% or 10% Llysine·H2SO4 supplementation produced negative responses on broiler performance,carcass characteristics,blood biochemistry,and particularly on intestinal morphology and liver pathology compared with broilers fed the control diet.Conclusion: Our results show that supplementation with 1% L-lysine·H2SO4 had no negative effects on performance,carcass characteristics,blood biochemistry,intestinal morphology and liver pathology in broilers,but supplementation with 4%,7% or 10% L-lysine·H2SO4 produced a negative response,particularly with respect to intestinal morphology and liver pathology.展开更多
[Objectives]Protoplast fusion of two parental strains with weak L-lysine production ability was carried out to obtain new fusion strains with strong L-lysine production ability.[Methods]The effects of bacterial age,ly...[Objectives]Protoplast fusion of two parental strains with weak L-lysine production ability was carried out to obtain new fusion strains with strong L-lysine production ability.[Methods]The effects of bacterial age,lysozyme concentration,enzymolysis temperature and time on the protoplast formation rate and regeneration rate were investigated by single factor experiments.On this basis,with the protoplast formation rate as an index,the protoplast preparation process was optimized by an orthogonal experiment.[Results]Bacterial age and enzymolysis time had a greater impact on the protoplast formation rate,followed by enzymolysis temperature and lysozyme concentration.The optimal process for the preparation of L-lysine-producing Escherichia coli protoplasts was to prepare parental protoplasts from bacterial cells cultured for 15 h in the late logarithmic growth phase by enzymolysis with 0.8 mg/ml lysozyme at 37℃for 180 min and promote fusion with PEG6000.In order to facilitate the screening of fusion protoplasts,the empty plasmids p ET-28a and p ET-Duet were transformed into L-lysine-producing E.coli,respectively,and strains p ET-28a-lys01 and p ET-Duet-lys01 were obtained.Fusion strains were then obtained through protoplast fusion.Double-resistance KA1-10were screened on plates containing kanamycin and ampicillin,and a high-yielding fusion strain KA8,which produced L-lysine,was screened by fermentation experiments finally.[Conclusions]The results of this study provide a reference method for further improving the yield of L-lysine and other amino acid strains.展开更多
The aim of this study was to estimate the effect of L-lysine on nodule formation by rat bone marrow cells in vitro. In this study, L-lysine was added to medium for mesenchymal stem cell culture to promote proliferatio...The aim of this study was to estimate the effect of L-lysine on nodule formation by rat bone marrow cells in vitro. In this study, L-lysine was added to medium for mesenchymal stem cell culture to promote proliferation and differentiation of the cells, and then nodule formation was estimated in an in vitro rat bone marrow cell culture. Bone marrow cells from the bone shafts of the femora of Fischer 344 rats were cultured in minimum essential medium with 20 μl of L-lysine solution at 10﹣4, 10﹣5, 10﹣6, 10﹣7 or 10﹣8 M. Dexamethasone was also added to the medium at 10 nM for differentiation of stem cells from bone marrow into osteoblast progenitor cells. The subculture was performed for 2 weeks. The quantity of osteocalcin in rat bone marrow cell culture with dexamethasone was 392 ng/ml. In the medium with dexamethasone and 10﹣8 M L-lysine, the quantity of osteocalcin was 437 ng/ml. Nodules only formed upon addition of 20 μl of L-lysine at 10﹣8 M. It was indicated that 10﹣8 M L-lysine should be the optimal concentration for calcification. For nodule formation by rat bone marrow cells in vitro, the optimum concentration of L-lysine in culture medium might be 20 μl of 10﹣8 M. L-lysine could play an important role in matrix production for bone formation in vitro.展开更多
Green solvents for cellulose dissolution is a key topic for green chemistry,especially natural cellulose with high molecular weight,and there are scarce solvents reported.Deep eutectic solvent(DES)is a typical kind of...Green solvents for cellulose dissolution is a key topic for green chemistry,especially natural cellulose with high molecular weight,and there are scarce solvents reported.Deep eutectic solvent(DES)is a typical kind of green solvent that has been attracted much attention recently.Here,high molecular weight natural cellulose(DP>3000)was first isolated from wheat straw and then be directly dissolved in the choline/L-lysine(Ch/Lys)DES.The solution owns excellent stability,and the solubility reaches^5%.Rheological studies revealed that the natural cellulose can be well dispersed in the DES solution and showed gelation at high concentrations.The dissolved cellulose can be regenerated when the dilute acid aqueous solution was added into the solution.It provides an energy conversation and an environmentally friendly route to prepare a cellulose solution,which makes it possible to convert cellulose to valuable chemicals and materials in its homogeneous solution.展开更多
α,ε-N,N'-bis(L-cysteinyl)-L-lysine was synthesized and char- acterized for the first time.It was then employed as a bifunctional chelating agent to chelate technetium-99m and subsequently conjugated to fragment ...α,ε-N,N'-bis(L-cysteinyl)-L-lysine was synthesized and char- acterized for the first time.It was then employed as a bifunctional chelating agent to chelate technetium-99m and subsequently conjugated to fragment F(ab')_2 of anti-gastric tumor monoclonal antibody 3G9.The radiolabelled antibody was satisfactorily stable and immunoreactive.展开更多
An edge Lyman-alpha-based beam emission spectroscopy(LyBES)diagnostic,using a heating NBI(neutral beam injection)system,is currently under development on the HL-2A tokamak.The 20-channel edge LyBES,which is intended t...An edge Lyman-alpha-based beam emission spectroscopy(LyBES)diagnostic,using a heating NBI(neutral beam injection)system,is currently under development on the HL-2A tokamak.The 20-channel edge LyBES,which is intended to measure the density fluctuation in plasma edge(from R=1960 mm to R=2026 mm)with an improved spatial resolution of 3.3 mm,is a complement to the existing conventional beam emission spectroscopy(BES)diagnostic.In this article,we introduce the progress of LyBES diagnostic,including the collection optics,the monochromator,and the detector system.The reflectance of the collection mirrors is measured to be~82%at 122 nm,and the aberration geometrical radius of the collection optics is tested to be~150μm in the aimed area.The linear dispersion of the LyBES monochromator is designed to be~0.09 nm mm^(-1).The bandwidth of the detector system with the 5×10^(7)V A^(-1)preamplifier gain is measured to be~280 kHz,and the peak-to-peak noise of the detector system is tested to be~16 mV.The finalized design,components development and testing of the LyBES diagnostic have been completed at present,and an overall performance of the LyBES diagnostic is to be confirmed in the next HL-2A campaign.展开更多
Intermittent fasting can benefit breast cancer patients undergoing chemotherapy or immunotherapy.However,it is still uncertain how to select immunotherapy drugs to combine with intermittent fasting.Herein we observed ...Intermittent fasting can benefit breast cancer patients undergoing chemotherapy or immunotherapy.However,it is still uncertain how to select immunotherapy drugs to combine with intermittent fasting.Herein we observed that two cycles of fasting treatment significantly inhibited breast tumor growth and lung tissue metastasis,as well as prolonged overall survival in mice bearing 4T1 and 4T07 breast cancer.During this process,both the immunosuppressive monocytic-(M-)and granulocytic-(G-)myeloid-derived suppressor cell(MDSC)decreased,accompanied by an increase in interleukin(IL)7R^(+)and granzyme B^(+)T cells in the tumor microenvironment.Interestingly,we observed that Ly6G^(low)G-MDSC sharply decreased after fasting treatment,and the cell surface markers and protein mass spectrometry data showed potential therapeutic targets.Mechanistic investigation revealed that glucose metabolism restriction suppressed the splenic granulocytemonocyte progenitor and the generation of colony-stimulating factors and IL-6,which both contributed to the accumulation of G-MDSC.On the other hand,glucose metabolism restriction can directly induce the apoptosis of Ly6G^(low)G-MDSC,but not Ly6G^(high)subsets.In summary,these results suggest that glucose metabolism restriction induced by fasting treatment attenuates the immune-suppressive milieu and enhances the activation of CD3^(+)T cells,providing potential solutions for enhancing immune-based cancer interventions.展开更多
Objective:To investigate the effects of stilbene glycoside(TSG)on okadaic acid-induced apoptosis in human neuroblastoma cells(SH-SY5Y)via the PI3K/AKT pathway.Methods:The optimal concentration of OA was screened by CC...Objective:To investigate the effects of stilbene glycoside(TSG)on okadaic acid-induced apoptosis in human neuroblastoma cells(SH-SY5Y)via the PI3K/AKT pathway.Methods:The optimal concentration of OA was screened by CCK-8 assay,and SH-SY5Y cells were divided into control group,model group,TSG group,LY294002 group and LY294002+TSG group.The proliferation and apoptosis in each group were detected by CCK-8 and TUNEL assays;Western blotting method and real-time fluorescence quantitative polymerase chain reaction was used to detect the expression of PI3K,P-PI3K(Y607),AKT,P-AKT(Ser473),Bcl-2 and Bax proteins.The relative protein expression was represented by P-PI3K(Y607)/PI3K,P-AKT(Ser473)/AKT and Bcl-2/Bax gray ratio.Results:CCK-8 screened the optimal concentration of OA as 40 nmol/L.Compared with the control group,the model group increased relative cell viability,decreased apoptosis rate,the pathway and apoptotic proteins expression levels of P-PI3K(Y607)/PI3K,P-AKT(Ser473)/AKT and Bcl-2/Bax were decreased,and the mRNA expression levels of PI3K,AKT and Bcl-2 were decreased.Bax mRNA expression level increased(P<0.05);Compared with model group,TSG group increased relative cell viability,decreased apoptosis rate,increased protein expression levels of P-PI3K(Y607)/PI3K,P-AKT(Ser473)/AKT,Bcl-2/Bax,and increased mRNA expression levels of PI3K,AKT,and Bcl-2.Bax mRNA expression decreased(P<0.05),LY294002 group decreased relative cell viability,increased apoptosis rate,P-PI3K(Y607)/PI3K protein expression levels were significantly decreased(P<0.05),P-AKT(Ser473)/AKT and Bcl-2/Bax protein expression levels were significantly decreased,but there was no statistical significance,PI3K,AKT and Bcl-2 mRNA expression levels were decreased,and Bax mRNA expression levels were increased(all P<0.05);Compared with LY294002 group,LY294002+TSG group increased relative cell viability,decreased apoptosis rate,and the protein expression levels of P-PI3K(Y607)/PI3K,P-AKT(Ser473)/AKT and Bcl-2/Bax were increased.The mRNA expression levels of PI3K,AKT,Bcl-2 were increased,Bax was decreased(all P<0.05).Conclusion:Stilbene glycoside may alleviate okadaic acid-induced apoptosis in SH-SY5Y cells by interfering with the PI3K/AKT signaling pathway,which in turn regulates the expression of apoptotic factors such as Bcl-2 and Bax.展开更多
目的探讨Lys-C胰蛋白酶在国际临床化学组织(International Federation of Clinical Chemistry and Laboratory Medicine,IFCC)推荐的质谱法测定糖化血红蛋白的参考方法中的应用价值。方法分别用两种特异性蛋白水解酶(GLU-C胞内蛋白酶和L...目的探讨Lys-C胰蛋白酶在国际临床化学组织(International Federation of Clinical Chemistry and Laboratory Medicine,IFCC)推荐的质谱法测定糖化血红蛋白的参考方法中的应用价值。方法分别用两种特异性蛋白水解酶(GLU-C胞内蛋白酶和Lys-C胰蛋白酶)酶解血红蛋白后,进行SDS-PAGE电泳,衡量蛋白酶解的效率,再将消化后的血红蛋白进行质谱分析,测定标本中糖化血红蛋白的浓度。结果在相同的电泳条件下,Lys-C胰蛋白酶酶解血红蛋白的效率优于GLU-C;酶解后的血红蛋白标本经质谱方法分析可知,两种蛋白酶用于检测糖化血红蛋白浓度时,可以得到基本一致的结果,由两种方法绘制的标准曲线r2分别为0.929和0.998。结论在IFCC推荐的糖化血红的蛋白参考测量方法中,一直使用GLU-C胞内蛋白酶酶解血红蛋白,该研究尝试通过Lys-C胰蛋白酶的使用,降低整个实验成本。经结果分析,证实应用这两种特异性的蛋白酶检测糖化血红蛋白时,可以得到基本一致的结果,推荐使用文中所列方法将Lys-C胰蛋白酶作为酶解糖化血红蛋白的特异性蛋白酶。展开更多
基金The present study was supported by the 111 Project(B16044)of China
文摘Background: Lysine is used widely in livestock production due to the shortage of feed protein resources.Llysine·H2SO4 contains L-lysine sulphate as well as fermentation co-products which contain other amino acids and phosphorus.However,there are few articles about L-lysine·H2SO4 product regarding intestinal morphology and liver pathology of broiler chickens.In this article,we focus on the absorption and metabolism of L-lysine·H2SO4 revealed in the variation of intestinal morphology and liver pathology to determine the tolerance of chicks for L-lysine·H2SO4.Methods: To evaluate the tolerance of broilers for L-lysine·H2SO4,240 one day old broilers were allocated randomly to one of five dietary treatments which included corn-soybean diets containing 0,1%,4%,7% or 10% L-lysine·H2SO4(L-lysine content = 55%).Results: Supplementation of 1% L-lysine·H2SO4 in the diet had no negative effects.However,4%,7% or 10% Llysine·H2SO4 supplementation produced negative responses on broiler performance,carcass characteristics,blood biochemistry,and particularly on intestinal morphology and liver pathology compared with broilers fed the control diet.Conclusion: Our results show that supplementation with 1% L-lysine·H2SO4 had no negative effects on performance,carcass characteristics,blood biochemistry,intestinal morphology and liver pathology in broilers,but supplementation with 4%,7% or 10% L-lysine·H2SO4 produced a negative response,particularly with respect to intestinal morphology and liver pathology.
基金Supported by the Focus on Research and Development Plan in Shandong Province(2019JZZY011003,2020CXGC010603)National Natural Science Foundation of China(31801527)。
文摘[Objectives]Protoplast fusion of two parental strains with weak L-lysine production ability was carried out to obtain new fusion strains with strong L-lysine production ability.[Methods]The effects of bacterial age,lysozyme concentration,enzymolysis temperature and time on the protoplast formation rate and regeneration rate were investigated by single factor experiments.On this basis,with the protoplast formation rate as an index,the protoplast preparation process was optimized by an orthogonal experiment.[Results]Bacterial age and enzymolysis time had a greater impact on the protoplast formation rate,followed by enzymolysis temperature and lysozyme concentration.The optimal process for the preparation of L-lysine-producing Escherichia coli protoplasts was to prepare parental protoplasts from bacterial cells cultured for 15 h in the late logarithmic growth phase by enzymolysis with 0.8 mg/ml lysozyme at 37℃for 180 min and promote fusion with PEG6000.In order to facilitate the screening of fusion protoplasts,the empty plasmids p ET-28a and p ET-Duet were transformed into L-lysine-producing E.coli,respectively,and strains p ET-28a-lys01 and p ET-Duet-lys01 were obtained.Fusion strains were then obtained through protoplast fusion.Double-resistance KA1-10were screened on plates containing kanamycin and ampicillin,and a high-yielding fusion strain KA8,which produced L-lysine,was screened by fermentation experiments finally.[Conclusions]The results of this study provide a reference method for further improving the yield of L-lysine and other amino acid strains.
文摘The aim of this study was to estimate the effect of L-lysine on nodule formation by rat bone marrow cells in vitro. In this study, L-lysine was added to medium for mesenchymal stem cell culture to promote proliferation and differentiation of the cells, and then nodule formation was estimated in an in vitro rat bone marrow cell culture. Bone marrow cells from the bone shafts of the femora of Fischer 344 rats were cultured in minimum essential medium with 20 μl of L-lysine solution at 10﹣4, 10﹣5, 10﹣6, 10﹣7 or 10﹣8 M. Dexamethasone was also added to the medium at 10 nM for differentiation of stem cells from bone marrow into osteoblast progenitor cells. The subculture was performed for 2 weeks. The quantity of osteocalcin in rat bone marrow cell culture with dexamethasone was 392 ng/ml. In the medium with dexamethasone and 10﹣8 M L-lysine, the quantity of osteocalcin was 437 ng/ml. Nodules only formed upon addition of 20 μl of L-lysine at 10﹣8 M. It was indicated that 10﹣8 M L-lysine should be the optimal concentration for calcification. For nodule formation by rat bone marrow cells in vitro, the optimum concentration of L-lysine in culture medium might be 20 μl of 10﹣8 M. L-lysine could play an important role in matrix production for bone formation in vitro.
基金This work is supported by the National Natural Science Foundation of China(No.51673180 and 51873201).
文摘Green solvents for cellulose dissolution is a key topic for green chemistry,especially natural cellulose with high molecular weight,and there are scarce solvents reported.Deep eutectic solvent(DES)is a typical kind of green solvent that has been attracted much attention recently.Here,high molecular weight natural cellulose(DP>3000)was first isolated from wheat straw and then be directly dissolved in the choline/L-lysine(Ch/Lys)DES.The solution owns excellent stability,and the solubility reaches^5%.Rheological studies revealed that the natural cellulose can be well dispersed in the DES solution and showed gelation at high concentrations.The dissolved cellulose can be regenerated when the dilute acid aqueous solution was added into the solution.It provides an energy conversation and an environmentally friendly route to prepare a cellulose solution,which makes it possible to convert cellulose to valuable chemicals and materials in its homogeneous solution.
文摘α,ε-N,N'-bis(L-cysteinyl)-L-lysine was synthesized and char- acterized for the first time.It was then employed as a bifunctional chelating agent to chelate technetium-99m and subsequently conjugated to fragment F(ab')_2 of anti-gastric tumor monoclonal antibody 3G9.The radiolabelled antibody was satisfactorily stable and immunoreactive.
基金supported by Sichuan Science and Technology Program(No.2022JDJQ0038)the National Key R&D Program of China(Nos.2022YFE03100002 and 2018YFE0303102)National Natural Science Foundation of China(Nos.12205087 and 12075241)。
文摘An edge Lyman-alpha-based beam emission spectroscopy(LyBES)diagnostic,using a heating NBI(neutral beam injection)system,is currently under development on the HL-2A tokamak.The 20-channel edge LyBES,which is intended to measure the density fluctuation in plasma edge(from R=1960 mm to R=2026 mm)with an improved spatial resolution of 3.3 mm,is a complement to the existing conventional beam emission spectroscopy(BES)diagnostic.In this article,we introduce the progress of LyBES diagnostic,including the collection optics,the monochromator,and the detector system.The reflectance of the collection mirrors is measured to be~82%at 122 nm,and the aberration geometrical radius of the collection optics is tested to be~150μm in the aimed area.The linear dispersion of the LyBES monochromator is designed to be~0.09 nm mm^(-1).The bandwidth of the detector system with the 5×10^(7)V A^(-1)preamplifier gain is measured to be~280 kHz,and the peak-to-peak noise of the detector system is tested to be~16 mV.The finalized design,components development and testing of the LyBES diagnostic have been completed at present,and an overall performance of the LyBES diagnostic is to be confirmed in the next HL-2A campaign.
基金supported by the Postdoctoral Research Funds of Hebei Medical University(30705010016-3759)Natural Science Foundation of China(32272328)+4 种基金Natural Science Foundation of Hebei Province(B2022321001)National Key Research Project of Hebei Province(20375502D)Postdoctoral Research Project of Hebei Province(B2022003031)Science and Technology Research Program of Hebei Provincial Colleges(QN2023229)Hebei Provincial Key Laboratory of Nutrition and Health(2023YDYY-KF05)。
文摘Intermittent fasting can benefit breast cancer patients undergoing chemotherapy or immunotherapy.However,it is still uncertain how to select immunotherapy drugs to combine with intermittent fasting.Herein we observed that two cycles of fasting treatment significantly inhibited breast tumor growth and lung tissue metastasis,as well as prolonged overall survival in mice bearing 4T1 and 4T07 breast cancer.During this process,both the immunosuppressive monocytic-(M-)and granulocytic-(G-)myeloid-derived suppressor cell(MDSC)decreased,accompanied by an increase in interleukin(IL)7R^(+)and granzyme B^(+)T cells in the tumor microenvironment.Interestingly,we observed that Ly6G^(low)G-MDSC sharply decreased after fasting treatment,and the cell surface markers and protein mass spectrometry data showed potential therapeutic targets.Mechanistic investigation revealed that glucose metabolism restriction suppressed the splenic granulocytemonocyte progenitor and the generation of colony-stimulating factors and IL-6,which both contributed to the accumulation of G-MDSC.On the other hand,glucose metabolism restriction can directly induce the apoptosis of Ly6G^(low)G-MDSC,but not Ly6G^(high)subsets.In summary,these results suggest that glucose metabolism restriction induced by fasting treatment attenuates the immune-suppressive milieu and enhances the activation of CD3^(+)T cells,providing potential solutions for enhancing immune-based cancer interventions.
基金National Natural Science Foundation of China(No.81860709)Baise City Science and Technology Plan Project(No.Encyclopedia 20224139,Encyclopedia 20211807)2023 Youjiang Ethnic Medical College Graduate Innovation Program Project(No.YXCXJH2023013)。
文摘Objective:To investigate the effects of stilbene glycoside(TSG)on okadaic acid-induced apoptosis in human neuroblastoma cells(SH-SY5Y)via the PI3K/AKT pathway.Methods:The optimal concentration of OA was screened by CCK-8 assay,and SH-SY5Y cells were divided into control group,model group,TSG group,LY294002 group and LY294002+TSG group.The proliferation and apoptosis in each group were detected by CCK-8 and TUNEL assays;Western blotting method and real-time fluorescence quantitative polymerase chain reaction was used to detect the expression of PI3K,P-PI3K(Y607),AKT,P-AKT(Ser473),Bcl-2 and Bax proteins.The relative protein expression was represented by P-PI3K(Y607)/PI3K,P-AKT(Ser473)/AKT and Bcl-2/Bax gray ratio.Results:CCK-8 screened the optimal concentration of OA as 40 nmol/L.Compared with the control group,the model group increased relative cell viability,decreased apoptosis rate,the pathway and apoptotic proteins expression levels of P-PI3K(Y607)/PI3K,P-AKT(Ser473)/AKT and Bcl-2/Bax were decreased,and the mRNA expression levels of PI3K,AKT and Bcl-2 were decreased.Bax mRNA expression level increased(P<0.05);Compared with model group,TSG group increased relative cell viability,decreased apoptosis rate,increased protein expression levels of P-PI3K(Y607)/PI3K,P-AKT(Ser473)/AKT,Bcl-2/Bax,and increased mRNA expression levels of PI3K,AKT,and Bcl-2.Bax mRNA expression decreased(P<0.05),LY294002 group decreased relative cell viability,increased apoptosis rate,P-PI3K(Y607)/PI3K protein expression levels were significantly decreased(P<0.05),P-AKT(Ser473)/AKT and Bcl-2/Bax protein expression levels were significantly decreased,but there was no statistical significance,PI3K,AKT and Bcl-2 mRNA expression levels were decreased,and Bax mRNA expression levels were increased(all P<0.05);Compared with LY294002 group,LY294002+TSG group increased relative cell viability,decreased apoptosis rate,and the protein expression levels of P-PI3K(Y607)/PI3K,P-AKT(Ser473)/AKT and Bcl-2/Bax were increased.The mRNA expression levels of PI3K,AKT,Bcl-2 were increased,Bax was decreased(all P<0.05).Conclusion:Stilbene glycoside may alleviate okadaic acid-induced apoptosis in SH-SY5Y cells by interfering with the PI3K/AKT signaling pathway,which in turn regulates the expression of apoptotic factors such as Bcl-2 and Bax.
文摘目的探讨Lys-C胰蛋白酶在国际临床化学组织(International Federation of Clinical Chemistry and Laboratory Medicine,IFCC)推荐的质谱法测定糖化血红蛋白的参考方法中的应用价值。方法分别用两种特异性蛋白水解酶(GLU-C胞内蛋白酶和Lys-C胰蛋白酶)酶解血红蛋白后,进行SDS-PAGE电泳,衡量蛋白酶解的效率,再将消化后的血红蛋白进行质谱分析,测定标本中糖化血红蛋白的浓度。结果在相同的电泳条件下,Lys-C胰蛋白酶酶解血红蛋白的效率优于GLU-C;酶解后的血红蛋白标本经质谱方法分析可知,两种蛋白酶用于检测糖化血红蛋白浓度时,可以得到基本一致的结果,由两种方法绘制的标准曲线r2分别为0.929和0.998。结论在IFCC推荐的糖化血红的蛋白参考测量方法中,一直使用GLU-C胞内蛋白酶酶解血红蛋白,该研究尝试通过Lys-C胰蛋白酶的使用,降低整个实验成本。经结果分析,证实应用这两种特异性的蛋白酶检测糖化血红蛋白时,可以得到基本一致的结果,推荐使用文中所列方法将Lys-C胰蛋白酶作为酶解糖化血红蛋白的特异性蛋白酶。
