Biochemical characterization of variants of the Ehlers-Danlos syndrome type VI

Three variants of the Ehlers-Danlos syndrome type VI are described: a severe form with skeletal, dermal and ocular manifestations associated with a lack of hydroxylysine in skin and little lysyl hydroxylase activity in cultured fibroblasts; a similarly affected form with a nearly normal hydroxylsine content in skin, but with only little enzyme activity in cultured fibroblasts; and a predominantly ocular form with no biochemical abnormality in skin or cultured skin fibroblasts. The activities of prolyl 4-hydroxylase and the two hydroxylysyl glycosyltransferases were normal in all cases, and the failure to find lysyl hydroxylase activity was not due to altered solubility characteristics of the enzyme or to the presence of an enzyme inhibitor. The collagen produced in cell culture, however, was hydroxylated to a markedly higher extent than that found in skin. In both the mutant and control cells hydroxylation of lysyl residues was less sensitive to ascorbate deficiency than that of prolyl residues.     

金龟子绿僵菌对甾体底物11-α羟化反应的工艺

研究了金龟子绿僵茵（Metarhizium anisopliae）对甾体底物16α、17α-环氧黄体酮（16α，17α—epoxy-4-pregnene-3，20-dione）的羟化反应工艺，考察了培养基组成、接种量、投料时间、转化时间、溶料方式、发酵级数等因素，探索了稀释发酵液以提高转化效率的新工艺。     

3－酮－地索高诺酮中间体的合成

本文经几步反应，以化学方法引入１１β-位羟基，通过波谱分析，确证了所得物的化学结构。用该化学合成法引入１１β-位羟基的收率较原报道的有关微生物发酵法为高，而且合成方法简单，是一种比较好的化学引入１１位羟基的合成方法，为今后有关化合物的合成打下了基础。     

UPLC-ESI-Q-TOF-MS/MS分析白头翁皂苷B3在大鼠肠道菌群中的代谢产物

目的:研究大鼠肠道菌群对白头翁皂苷B_3的代谢作用,为皂苷类物质在肠道菌群的代谢特征研究提供参考。方法:以连翘苷为内标物,建立UPLC-ESI-Q-TOF-MS/MS检测条件,流动相乙腈(A)-水(B)梯度洗脱(0~8 min,10%~95%A;8~10 min,95%A;10~10.10 min,95%~10%A),流速0.3 m L·min~(-1),扫描方式为电喷雾(ESI)负离子模式,离子喷雾电压-3 500 V,碰撞电压130 V,干燥气流量12 L·min~(-1),温度350℃,鞘气流量12 L·min~(-1),温度350℃,碎裂电压分别为20,35,50 V。总离子流全扫描的范围m/z 100~1 100。采用负离子和多反应离子监测模式分析白头翁皂苷B_3与大鼠肠道菌群共孵育后的代谢产物。结果:从药物-菌群孵育液中鉴定出白头翁皂苷B3的3-位侧链脱糖代谢产物及苷元母核上羟化、羧化和脱羧、甲基化和去甲基化代谢产物共8种。结论:大鼠肠道菌群在实验条件下能有效代谢白头翁皂苷B3,提示上述代谢产物是其生物活性成分。     

对映选择性羟化乙基苯的碳氢键合成（R）-和（S）-1-苯基乙醇

目的 筛选出具有能对乙基苯的苄位C-H键发生对映选择性羟基化反应,并具有较好R和S选择性的菌株.方法 采用悬浮细胞生物转化法对乙苯的对映选择性羟基化进行研究,产物采用液相色谱法进行分析.结果 通过整细胞催化分别获得具有90％的转化率,86％ ee的（R）-1-苯基乙醇和具有91％的转化率,98％ ee的（S）-1-苯基乙醇.结论 菌株ZMU-T03和ZMU-T11分别对乙基苯苄位C-H键显示出了较好的？和（S）-选择性.     

药物羟化作用的多型性与治疗药物监测

药物羟化代谢表型测定与药物血液浓度常规测定结合，可使经羟化作用代谢而浓度－效应曲线陡峭，对仅根据临床表现难以确定治疗效应和毒性效应以及毒性大、疗效确实的药物的合理安全很有用处。     

Ecdysone 20-monooxygenase: characterization of an insect cytochrome p-450 dependent steroid hydroxylase.

Ecdysone 20-monooxygenase, the enzyme system that hydroxylates ecdysone at C-20 of the side-chain to form ecdysterone, has been characterized in the fat body of early last instar larvae of the tobacco hornworm, Manduca sexta, using a radioenzymological assay. Ecdysterone was demonstrated to be the product of the enzyme system by high-pressure liquid chromatography, gas-liquid chromatography and mass spectrometry. Differential centrifugation, sucrose-gradient centrifugation, electron microscopy and organelle-marker enzyme analysis revealed that ecdysone 20-monooxygenase activity is associated with the mitochondria. The enzymatic properties of ecdysone 20-monooxygenase are that it is most active in a 0.05 M phosphate buffer, is inhibited by Mg2+ and exhibits pH and temperature optima at 7.5 and 30 degrees C, respectively. The enzyme complex has an apparent Km for ecdysone of 1.60 x 10(-7) M and is competitively inhibited by its product, ecdysterone, with an apparent Ki of 2.72 x 10(-5) M. The cytochrome P-450 nature of this insect steroid hydroxylase was initially suggested by its obligate requirement for NADPH and its inhibition by carbon monoxide, p-chloromercuribenzoate, metyrapone and p-aminoglutethimide but not by cyanide. Difference spectroscopy revealed the presence of cytochrome P-450 in the fat-body mitochondrial fraction. A photochemical action spectrum of ecdysone 20-monooxygenase activity confirmed the involvement of cytochrome P-450 in this monooxygenase system.     

4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone, a component of tobacco smoke, modulates mediator release from human bronchial and alveolar epithelial cells

Respiratory epithelial cells are known to contribute to immune responses through the release of mediators. The aim of this study was to characterize the immunomodulatory effects of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), a tobacco carcinogen, on respiratory epithelial cells and to compare two metabolic pathways, alpha-methylhydroxylation and alpha-methylenehydroxylation, involved in these effects using selective precursors, 4-(acetoxy-methylnitrosamino)-1-(3-pyridil)-1-butanone (NNKOAc) and N-nitroso (acetoxymethyl) methylamine (NDMAOAc), respectively. Human bronchial and alveolar epithelial cell lines, BEAS-2B and A549, respectively, were treated with NNK, NNKOAc and NDMAOAc for 24 h with and without tumour necrosis factor (TNF) and mediators released in cell-free supernatants were measured by enzyme-linked immunosorbent assay (ELISA). NNK significantly inhibited interleukin (IL)-8, IL-6 and monocyte chemoattractant protein-1 (MCP-1) production in both cell types. Similar results were observed with primary bronchial and alveolar epithelial cells. Although NNK increased prostaglandin E(2) (PGE(2)) production by A549 cells, its immunomodulatory effects were not mediated by PGE(2) according to the results with cyclo-oxygenase inhibitors. NNKOAc mimicked NNK effects, whereas NDMAOAc significantly inhibited IL-8 production in BEAS-2B cells and MCP-1 in both cell types. These results demonstrate that NNK and its reactive metabolites have immunosuppressive effects on respiratory epithelial cells, which could contribute to the increased respiratory infections observed in smokers and the development and/or the progression of lung cancer.