Fungal alkylresorcinols are a class of polyketides,which are commonly synthesized by the hybridization of highly reducing polyketide synthase(hrPKS)with non-reducing polyketide synthase(nrPKS).In this study,we identif...Fungal alkylresorcinols are a class of polyketides,which are commonly synthesized by the hybridization of highly reducing polyketide synthase(hrPKS)with non-reducing polyketide synthase(nrPKS).In this study,we identified and demonstrated a new assembly model for synthesizing alkylresorcinol(scirpilin A,1),which was accomplished by collaboration of a hrPKS(FscA)and a typeⅢPKS(FscB).Furthermore,three post-tailoring enzymes(FscC,FscD,and FscE)act iteratively on 1 skeleton,including successive 14e-oxidation of inert carbons,di-halogenation,and di-methylation,to form highly oxidized and multisubstituted alkylresorcinols.Our work presents an unusual synthesis manner of alkylresorcinols,sheds light on the collaborative mechanism between hrPKS and typeⅢPKS and provides three valuable enzymatic catalysts for the tailoring of alkylresorcinol family natural products in future.展开更多
建立气相色谱-质谱(gas chromatography-mass spectrometry,GC-MS)联用法和液相色谱-串联质谱(liquid chromatography-tandem mass spectrometry,LC-MS/MS)法测定麦粉中烷基间苯二酚组成。样品经乙酸乙酯超声提取,在GC-MS中,硅烷化衍生...建立气相色谱-质谱(gas chromatography-mass spectrometry,GC-MS)联用法和液相色谱-串联质谱(liquid chromatography-tandem mass spectrometry,LC-MS/MS)法测定麦粉中烷基间苯二酚组成。样品经乙酸乙酯超声提取,在GC-MS中,硅烷化衍生处理,采用选择离子监测模式进行测定,以外标法进行定量;在LC-MS/MS中,经固相萃取富集净化,以C18色谱柱分离,采用电喷雾负离子模式扫描、多反应监测模式检测,以外标法进行定量。结果表明,GC-MS和LC-MS/MS均在0.001~5μg/mL质量浓度范围内有良好的线性关系(R^(2)>0.98),GC-MS法的检出限为2.0~6.1μg/g,加标回收率在94.17%~99.15%之间,相对标准偏差(relative standard deviation,RSD)在2.94%~4.87%之间;LC-MS/MS法的检出限为2.0~8.4μg/g,加标回收率在89.05%~99.06%之间,RSD在2.21%~4.17%之间。本研究建立了2种线性关系良好、低检测限、高灵敏度的检测方法,均可适用于市售麦粉产品中烷基间苯二酚同系物定性定量分析,将为麦类全谷物产品品质控制与检测提供技术指导。展开更多
基金supported by the National Natural Science Foundation of China(No.22277100)the National Key R&D Program of China(No.2020YFA0907700)+2 种基金the Fundamental Research Funds for the Central Universities(Nos.SWU-KQ22034 and SWUXDPY22009)the Science and Technology Innovation Key R&D Program of Chongqing(No.CSTB2022TIAD-STX0015)the Chongqing Science Funds for Distinguished Young Scientists(No.cstc2020jcyj-jqX0005)。
文摘Fungal alkylresorcinols are a class of polyketides,which are commonly synthesized by the hybridization of highly reducing polyketide synthase(hrPKS)with non-reducing polyketide synthase(nrPKS).In this study,we identified and demonstrated a new assembly model for synthesizing alkylresorcinol(scirpilin A,1),which was accomplished by collaboration of a hrPKS(FscA)and a typeⅢPKS(FscB).Furthermore,three post-tailoring enzymes(FscC,FscD,and FscE)act iteratively on 1 skeleton,including successive 14e-oxidation of inert carbons,di-halogenation,and di-methylation,to form highly oxidized and multisubstituted alkylresorcinols.Our work presents an unusual synthesis manner of alkylresorcinols,sheds light on the collaborative mechanism between hrPKS and typeⅢPKS and provides three valuable enzymatic catalysts for the tailoring of alkylresorcinol family natural products in future.
文摘目的探讨5-烷基间苯二酚(5-alkylresorcinols,5ARs)诱导人结直肠癌细胞凋亡及与BCL2、Bax、PARP1和Caspase3表达的影响.方法体外细胞实验应用5AR s直接对HT29、HCT116进行干预诱导.利用倒置相差显微镜观察5ARs对HT29、HCT116干预后细胞形态的变化.CCK8法测定不同浓度5ARs诱导人HT29及HCT116抑制率.Annexin V-F ITC/P I流式细胞术检测5ARs诱导人HT29及HCT116凋亡.Western-blot检测分析不同浓度5ARs诱导HT29及HCT116后凋亡相关蛋白变化(BCL2、Bax、PARP1和Caspase3).结果5A R s可呈浓度依赖性地抑制H T 2 9及HCT116增殖(P<0.05);5ARs可诱导HT29及HCT116凋亡,并可增强Bax、PARP1和Caspase3表达,抑制BCL2表达,并提高Bax/BCL2的比值比例(P<0.05).结论5ARs可诱导HT29及HCT116凋亡,并且可能与激活Bax、PARP1和Caspase3表达及增加Bax/BCL2比值比例相关.
文摘建立气相色谱-质谱(gas chromatography-mass spectrometry,GC-MS)联用法和液相色谱-串联质谱(liquid chromatography-tandem mass spectrometry,LC-MS/MS)法测定麦粉中烷基间苯二酚组成。样品经乙酸乙酯超声提取,在GC-MS中,硅烷化衍生处理,采用选择离子监测模式进行测定,以外标法进行定量;在LC-MS/MS中,经固相萃取富集净化,以C18色谱柱分离,采用电喷雾负离子模式扫描、多反应监测模式检测,以外标法进行定量。结果表明,GC-MS和LC-MS/MS均在0.001~5μg/mL质量浓度范围内有良好的线性关系(R^(2)>0.98),GC-MS法的检出限为2.0~6.1μg/g,加标回收率在94.17%~99.15%之间,相对标准偏差(relative standard deviation,RSD)在2.94%~4.87%之间;LC-MS/MS法的检出限为2.0~8.4μg/g,加标回收率在89.05%~99.06%之间,RSD在2.21%~4.17%之间。本研究建立了2种线性关系良好、低检测限、高灵敏度的检测方法,均可适用于市售麦粉产品中烷基间苯二酚同系物定性定量分析,将为麦类全谷物产品品质控制与检测提供技术指导。