2012年11月7日,在法国国家药学科学院（AcadémieNationale de Pharmacie）的院士大会上,北医（北京大学医学部,原北京医学院、北京医科大学,简称北医）77级药学系药物化学专业学生、现法国皮埃尔与玛丽-居里大学博士生导师、法国...2012年11月7日,在法国国家药学科学院（AcadémieNationale de Pharmacie）的院士大会上,北医（北京大学医学部,原北京医学院、北京医科大学,简称北医）77级药学系药物化学专业学生、现法国皮埃尔与玛丽-居里大学博士生导师、法国国家科学研究中心（Centre national de la recherche scientifique,CNRS）主任研究员、展开更多
目的:研究中药黄芩主要黄酮类成分及其生物活性。方法:用色谱法分离,通过理化性质及波谱方法鉴定结构,采用多菌种、应用细胞及分子水平方法测定主要黄酮类成分的生物活性。结果:分离鉴定了9个化合物,分别为黄芩素(1)、汉黄芩素(2)、千...目的:研究中药黄芩主要黄酮类成分及其生物活性。方法:用色谱法分离,通过理化性质及波谱方法鉴定结构,采用多菌种、应用细胞及分子水平方法测定主要黄酮类成分的生物活性。结果:分离鉴定了9个化合物,分别为黄芩素(1)、汉黄芩素(2)、千层纸素A(3)、5,7,2′,6′-四羟基黄酮(4)、粘毛黄芩素Ⅲ(5)、黄芩苷(6)、汉黄芩苷(7)、千层纸素A-7-O-β-D-葡萄糖醛酸苷(8)、白杨素-6-C-α-L-阿拉伯吡喃糖-8-C-β-D-葡萄吡喃糖苷(9)。化合物1～7中,有邻三羟基的黄芩素抗菌活性最强,且具有良好的量效关系;有邻三取代和多羟基的黄酮具有抑制白细胞介素-1β转化酶(IL-1βcoverting enzyme,ICE)的活性。结论:研究结果为建立黄芩质量控制方法提供了科学依据,并在分析二维核磁共振(nuclear magnetic resonance,NMR)数据的基础上,对化合物9的13C NMR数据进行了正确归属。展开更多
Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration ...Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Iα-loop-helix Iβmotif which corresponds to helix I of other P 450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,theγ-domain.The structure reveals a homodimer in which theγ-domain of one molecule interacts with theβ-domain of another.The plane of heme group makes an angle of approximately 40°with the helix Iα-loop-helix Iβmotif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recognition.Phe-301,Ser-303 and Gly-305 from the helix Iα-loop-helix Iβmotif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.展开更多
文摘2012年11月7日,在法国国家药学科学院（AcadémieNationale de Pharmacie）的院士大会上,北医（北京大学医学部,原北京医学院、北京医科大学,简称北医）77级药学系药物化学专业学生、现法国皮埃尔与玛丽-居里大学博士生导师、法国国家科学研究中心（Centre national de la recherche scientifique,CNRS）主任研究员、
文摘目的:研究中药黄芩主要黄酮类成分及其生物活性。方法:用色谱法分离,通过理化性质及波谱方法鉴定结构,采用多菌种、应用细胞及分子水平方法测定主要黄酮类成分的生物活性。结果:分离鉴定了9个化合物,分别为黄芩素(1)、汉黄芩素(2)、千层纸素A(3)、5,7,2′,6′-四羟基黄酮(4)、粘毛黄芩素Ⅲ(5)、黄芩苷(6)、汉黄芩苷(7)、千层纸素A-7-O-β-D-葡萄糖醛酸苷(8)、白杨素-6-C-α-L-阿拉伯吡喃糖-8-C-β-D-葡萄吡喃糖苷(9)。化合物1～7中,有邻三羟基的黄芩素抗菌活性最强,且具有良好的量效关系;有邻三取代和多羟基的黄酮具有抑制白细胞介素-1β转化酶(IL-1βcoverting enzyme,ICE)的活性。结论:研究结果为建立黄芩质量控制方法提供了科学依据,并在分析二维核磁共振(nuclear magnetic resonance,NMR)数据的基础上,对化合物9的13C NMR数据进行了正确归属。
文摘Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Iα-loop-helix Iβmotif which corresponds to helix I of other P 450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,theγ-domain.The structure reveals a homodimer in which theγ-domain of one molecule interacts with theβ-domain of another.The plane of heme group makes an angle of approximately 40°with the helix Iα-loop-helix Iβmotif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recognition.Phe-301,Ser-303 and Gly-305 from the helix Iα-loop-helix Iβmotif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.
