透明颤菌血红蛋白基因的克隆及其在林可链霉菌中的表达

目的通过将透明颤菌血红蛋白基因vgb克隆到林可链霉菌染色体黑色素生物合成基因m elC位点,使m elC基因被破坏失活,vgb基因实现表达同时提高林可霉素产量。方法构建大肠杆菌-链霉菌重组质粒pYHT04,通过接合转移实验将重叠延伸PCR得到的具有红霉素抗性基因启动子的透明颤菌血红蛋白基因,以双交换的方式整合进林可链霉菌黑色素生物合成基因m elC中。采用不同装瓶量摇瓶发酵,HPLC检测发酵液中林可霉素含量。结果重组菌株颜色变浅,CO结合差光谱显示在420 nm处有明显吸收峰,随着装瓶量的增加重组菌株发酵液中林可霉素效价与对照菌株相比降低幅度较小。结论重组菌株m elC基因失活不能继续合成黑色素,vgb基因得到表达并表现出生物学功能,限氧条件下重组菌株发酵液中林可霉素效价高于对照菌株,有希望应用于工业发酵生产。     

林可霉素基因工程研究的新进展

摘要：林可霉素是一种由林可链霉菌产生的林可酰胺类抗生素,主要用于防治由革兰阳性菌引发的感染。近年来,随着林 可链霉菌基因组测序的完成,林可霉素基因工程研究进展迅速。本文就近期林可霉素生物合成及其调控的研究进行总结,并重 点介绍在结构基因、调控基因、抗性基因和代谢前体基因的改造方面实现林可霉素定向高产,以及新型林可霉素衍生物创制的 新进展。     

林可链霉菌与委内瑞拉链霉菌种间原生质体融合的研究

本文报道氯霉素产生菌委内瑞拉链霉菌A-186株与林可霉素产生菌林可链霉菌林可变种78-11株种间原生质体融合的结果。首先,研究了委内瑞拉链霉菌A-186的原生质体制备和再生条件,再生率可达86％。然后,采用氯霉素产生菌S.venezuelae A-186的原生质体用紫外线灭活后,与具有耐药标记的S.lincolnensis var.lincolnensis78-11原生质体融合的方法,种间融合频率达到3.2×10~(-5) 。并筛选到一株遗传稳定的重组子,经初步鉴定它能同时产生两亲株所产的两种抗生素。     

林可霉素生物合成基因lmbH的回转化

以ＰＩＪ７０２或ＰＩＪ４８６为载体构建了３个含有ｌｍｂＨ基因的重组质粒ｐＥＳＳ７０１、ｐＥＳＳ７０４和ｐＥＳＳ７０８分子,分别回转化林可霉素产生菌Ｂ４８,并随机挑选了６００个回转化克隆进行摇瓶初筛,以抑菌圈直长作为稀理林可霉素产生量的标准。     

林可霉素生物合成缺陷的同源重组菌鉴定

以S．lincolnensis B48为对照，分别测定两个染色体上含lmbI基因灭活拷贝的菌株YYl(同源交换)、YY2(同源整合)的抗菌效价，其中YYl在其整个生物周期中均无明显抗菌效价，而YY2的效价与B48相比也明显伯低。进一步通过PCR反应验证这两株基因工程菌lmbI基因灭活情形，结果发现YYl染色体上lmbI基因的两个拷贝均因同源交换而被灭活，而YY2可能是因单拷贝发生同源整合而仅被部分灭活。     

头霉素关键中间体7-MAC的合成方法改进

目的改进头霉素关键中间体7α-甲氧基-7β-氨基-3-[（1-甲基-1H-四氮唑-5-基）硫甲基]头孢-3-烯4-羧酸二苯甲酯（7-MAC）的合成方法。方法以7-氨基-3-乙酰氧甲基头孢烯酸（7-ACA）为原料,经亲核取代反应合成3-（1-甲基-1胁四氮唑-5-基）硫甲基-7-氨基头孢烯酸（2）,2经取代．消除反应、酯化反应制得7-甲硫亚胺-3-[（1-甲基-1H-四氮唑-5-基）硫甲基]头孢-3-烯4-羧酸二苯甲酯（5）,在中间体5的7α位引入甲氧基制得目标化合物7-MAC。结果与结论目标化合物的结构经质谱、核磁共振氢谱确证,总收率为60％以上,纯度为99．1％,透光率高于75％。该方法反应条件温和,得到的产品质量好,有利于工业化生产。     

含双环哌啶结构 HIV-1 抑制剂的设计合成及生物活性研究

目的 设计合成一系列具有新型结构特征的双环哌啶类 C-C 族趋化因子受体5(CCR5) 抑制剂并测定其抗 HIV-1 活性。方法 以HIV-1 辅助受体 CCR5 抑制剂 Vicriviroc 的结构为模板,通过改变左侧哌嗪结构、取代基位置等方法设计并合成一系列新化合物。并利用 MS 及 ¹H-NMR 谱对这些化合物进行了结构表征。结果与结论 合成了 15 个新结构化合物,活性测试结果表明,该系列化合物具有较强的抗 HIV-1 R5 病毒株的活性 (IC₅₀ = 1.20 ～ 66.24 µmol·L^-1 )。 当 R¹ 为芳基结构且两个氮原子满足标准的丙二胺结构时,化合物的活性更好。     

24孔板优化林肯链霉菌发酵培养基

目的 优化林肯链霉菌发酵培养基。方法 采用24孔板,对现有的两种发酵培养基中各因素进行考察,筛选出较优发酵培养基;在此发酵培养基基础上,采用L25(56)正交设计方法,对可溶性淀粉、葡萄糖、豆饼粉、硫酸铵、玉米浆和磷酸氢二钾这6个可能影响林可霉素发酵水平的因素进行效应评价。结果 得到最佳发酵培养基(g/L)：可溶性淀粉30,葡萄糖105,豆饼粉22.5,玉米浆1,氯化钠2.25,碳酸钙6,硫酸铵2.65,硝酸钾1,磷酸氢二钾0.5。结论 对优化后的发酵培养基进行孔板发酵验证,林可霉素的平均发酵产量达到2288μg/mL,比未优化组提高了42.03%。     

薤中抗凝和抗癌活性成分的结构鉴定

从百合科葱属植物薤(Alium chinense)鳞茎的抗凝和抗癌活性部位中,分离得到了6个化合物。经过化学方法和光谱分析(IR,EI-MS,¹HNMR,¹³HNMR,¹H-¹HCOSY,HMBC,HMQC和NOESY谱),鉴定它们的结构分别为(25R,S)-5α-spirostane-3β-ol 3-O-｛β-D-glucopyranosyl-(1→2)-[β-D-glucopyra-nosyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside｝(1),(25R,S)-5α-spirostane-3β-ol 3-O-｛β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→3)](6-acetyl-β-D-glucopyranosyl)-(1→4)-β-D-galac-topyranoside｝(2),(25R,S)-5α-spirostane-2α,3β-diol3-O-｛β-D-glucopyranosyl-(1→2)-O-β-D-glucopyra-nosyl-(1→4)-β-D-galactopyranoside｝(3),(25S)-24-O-β-D-glucopyranosyl 3β,24β-dihydroxy-5α-spirost-3-O-α-arabinopyranosyl-(1→6)-β-D-glucopyranoside(4),chinenosideI(5)及2,3,4,9-tetrahydro-1-methyl-1H-pyrido[3,4-b]indole-3-carboxylicacid(6)。化合物4为一新的甾体皂甙,命名为chinenosideVI。化合物1～3为3对甾体皂甙差向异构体。其中,化合物2的25S型异构体为首次报道;25R型异构体和化合物6为首次从本种植物中分得。此外,通过NOESY谱还首次确定了化合物6的相对构型,并对其C和H信号进行了确切归属。     

应用原生质体融合法选育林可霉素高产菌株

将林可霉素产生菌N65—2^#、S78—1^#的原生质体分别热灭活和紫外灭活，并将灭活原生质体用PEG融合，从中获得92-201^#融合株，其摇瓶效价分别较N65—2^#、S78—1^#提高17％、52％，且色素分泌少，传代稳定性强。     

Regulation of the activity of microbial kynureninase by transamination of the enzyme-bound coenzyme.

Kynureninase was purified to homogeneity from the extracts of Pseudomonas marginalis and Neurospora crassa. The active kynureninase containing pyridoxal 5'-phosphate transaminates with L-ornithine or L-alanine to form the inactive pyridoxamine 5'-phosphate form of enzyme and delta1-pyrroline-2-carboxylate or pyruvate. This inactive enzyme transaminates with pyruvate to restore the active pyridoxal 5'-phosphate enzyme and L-alanine. The activity of kynureninase is regulated in this manner by transamination of the coenzyme moiety.     

抗肿瘤药物苹果酸舒尼替尼的合成

目的 合成抗肿瘤药物苹果酸舒尼替尼。方法 以乙酰乙酸叔丁酯为起始原料，通过Knorr吡咯合成法、脱叔丁氧羰基、Vilsmeier甲酰化、酯水解反应得中间体5-甲酰基-2,4-二甲基-1H-吡咯-3-羧酸（6），6与碳酰二咪唑反应生成酰基咪唑，不经分离直接用“一锅煮”方法与5-氟吲哚啉-2-酮和2-(二乙氨基)乙二胺缩合，最后成盐得到苹果酸舒尼替尼。 结果与结论 合成的苹果酸舒尼替尼经核磁共振、质谱和元素分析确证结构，总收率达28%。     

Isolation and structure determination of oxidative degradation products of atorvastatin

Methods were developed for the preparation and isolation of four oxidative degradation products of atorvastatin. ATV-FX1 was prepared in the alkaline acetonitrile solution of atorvastatin with the addition of hydrogen peroxide. The exposition of aqueous acetonitrile solution of atorvastatin to sunlight for several hours followed by the alkalization of the solution with potassium hydroxide to pH 8–9 gave ATV-FXA. By the acidification of the solution with phosphoric acid to pH 3 ATV-FXA1 and FXA2 were prepared. The isolation of oxidative degradation products was carried out on a reversed-phase chromatographic column Luna prep C18(2) 10 μm applying several separation steps. The liquid chromatography coupled with a mass spectrometer (LC-MS), high resolution MS (HR-MS), 1D and 2D NMR spectroscopy methods were applied for the structure elucidation. All degradants are due to the oxidation of the pyrrole ring. The most probable reaction mechanism is intermediate endoperoxide formation with subsequent rearrangement and nucleophilic attack by the 5-hydroxy group of the heptanoic fragment. ATV-FX1 is 4-[1b-(4-Fluoro-phenyl)-6-hydroxy-6-isopropyl-1a-phenyl-6a-phenylcarbamoyl-hexahydro-1,2-dioxa-5a-aza-cyclopropa[a]inden-3-yl]-3-(R)-hydroxy-butyric acid and has a molecular mass increased by two oxygen atoms with regard to atorvastatin. ATV-FXA is the regioisomeric compound, 4-[6-(4-Fluoro-phenyl)-6-hydroxy-1b-isopropyl-6a-phenyl-1a-phenylcarbamoyl-hexahydro-1,2-dioxa-5a-aza-cyclopropa[a]inden-3-yl]-3-(R)-hydroxy-butyric acid. Its descendants ATV-FXA1 and FXA2 appeared without the atorvastatin heptanoic fragment and are 3-(4-Fluoro-benzoyl)-2-isobutyryl-3-phenyl-oxirane-2-carboxylic acid phenylamide and 4-(4-Fluoro-phenyl)-2,4-dihydroxy-2-isopropyl-5-phenyl-3,6-dioxa-bicyclo[3.1.0]hexane-1-carboxylic acid phenylamide, respectively. Quantitative NMR spectroscopy was employed for the assay determination of isolated oxidative degradation products. The results obtained were used for the determination of the UV response factors relative to atorvastatin.     

PREPARATION OF RACEMIC 2r-CARBOXY-TRANS,TRANS-3, 4-DIDEUTERO-PYRROLIDINE (DL-TRANS,TRANS-3, 4-DIDEUTERO-PROLINE) AND UNAMBIGUOUS ASSIGNMENT OF PROTONS IN THE 1H N.M.R. SPECTRUM OF PROLINE

Racemic trans, trans-3,4-dideutero proline has been prepared by catalytic deuteration of 3-pyrroline-2-carboxylic acid. The stereospecificity of the reduction (i.e. trans to the carboxylic group) was ascertained after transformation of the dideutero compound into the diketopiperazide c/Pro, Aib/, for which unambiguous proton assignments in the ¹H n.m.r. spectrum had been obtained previously. The identification of the configuration of the dideutero-proline allows for the affirmation of the correctness of proton assignments as previously proposed in literature.     

应用双亲株灭活原生质体融合法选育林可霉素高产菌株

目的：选育高产优质林可霉素产生菌。方法：将林可霉素产生菌S78－1^#,N65-2^#的原生质体分别热灭活和紫外灭活，并将两种灭活原生质体用PEG融合，从融合株中筛选高产优质菌种。结果：获得82－201^#融合株，其摇瓶效价分别较N65－2^#,S78-2^#提高17％和52％，且色素分泌少，传代稳定性强。结论：双亲株灭活原生质体融合选育林可霉素高产菌株是值得推广的一种选育方法。     

Composition analysis and antioxidant properties of black garlic extract

Black garlic produced from fresh garlic under controlled high temperature and humidity has strong antioxidant properties. To determine these compounds, five fractions (from F1 to F5) were separated and purified by elution with chloroform:methanol at different ratios (8:1, 6:1, 4:1, 2:1, and 0:1; v/v). The antioxidant activity of each fraction was analyzed. The results showed that F3 and F4 had higher phenolic contents and stronger 2,2-diphenyl-2-picrylhydrazyl radical scavenging activity than the others. Seven purified individual components were further separated using semipreparation high-performance liquid chromatography from these two intensely antioxidant fractions (F3 and F4), their structures were elucidated by high-performance liquid chromatography coupled to diode array detection, electrospray ionization, mass spectrometry, ¹H nuclear magnetic resonance, and ¹³C nuclear magnetic resonance spectrometry. Three compounds including adenosine, uridine, and 2-acetylpyrrole were first identified in black garlic, except for 5-hydroxymethylfurfural, (1S, 3S)-1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid, and (1R, 3S)-1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid. The cellular antioxidant activities of uridine, adenosine, carboline alkaloids, 5-hydroxymethylfurfural, and ethyl acetate extracts were consistent with the results of in vitro experimental antioxidant properties. The results provide useful information for understanding the health benefits of black garlic products.     

HPLC determination of lincomycin in premixes and feedstuffs with solid-phase extraction on HLB OASIS and LC-MS/MS confirmation

A rapid clean-up procedure based on solid-phase extraction (SPE) and HPLC determination of lincomycin in premixes with UV detection is described. After extraction of lincomycin from premix with extraction solvent the extract is applied to OASIS HLB column treated with methanol and water. Lincomycin is eluted with methanol and effluent is analysed on analytical column (phenyl) using mobile phase consists 0.2% phosphoric acid in water and acetonitrile (875:125, v/v). Detection is performed at 208 nm. Quantitation is carried out using external standard. The mean recovery of lincomycin was 105.0+/-7.3%, in concentration range of 250-750 mg kg(-1), and 99.8+/-3.7%, in concentration range of 10,000-150,000 mg kg(-1). The limit of determination, based on a signal-to-noise ratio of 10:1, was 5.2 mg kg(-1). LC-MS/MS confirmation of lincomycin is also presented. Identification was performed by monitoring two pairs of multiple reaction monitoring ions from the parent ions (m/z 407.2-->126.1 and 407.2-->359.2) at the defined retention time window and by matching of the specific tolerance of relative abundance of major ions as stated in the European Union Commission Decision 2002/657/EC.     

头孢克肟及其关键中间体7-AVCA的合成工艺改进

目的 研究头孢克肟及其关键中间体7-AVCA的合成工艺,以酶解法替代传统化学裂解法.方法 经工艺考察及改进,最终确定以GCLE为起始原料,经关键中间体7-AVCA制备头孢克肟适合于生产的工艺.结果 所制得的头孢克肟质量好,总收率为64%.其中采用的酶解法工艺不仅解决了环保治理的瓶颈问题,同时改进工艺获得的中间体7-AVCA的质最明显优于其他方法,优质的7-AVCA从源头上起到提高下游原料药头孢克肟产品的含量及稳定性,降低杂质的作用.头孢克肟的结构经1H-NMR、IR和UV分析确证,色谱纯度经HPLC检测大于99%.结论 本文工艺与文献相比,操作简化,收率提高,产品质量优异,节能环保,适合于产业化.     

非布司他降解产物的LC-MS研究

目的研究非布司他的降解产物。方法强制降解后以LC-MS测定,根据质谱测定结果结合结构及反应机制推测降解产物结构。结果推测降解产物为2-[3-氰基-4-(2-异丁氧基)苯基]-4-甲基噻唑-5-羧酸甲酯、2-[3-氨基甲酰基-4(2-异丁氧基-)苯基]-4-甲基噻唑-5-羧酸、2-[3-氰基-4-(2-异丁氧基)苯基]-4-甲基-1-氧化噻唑-5-羧酸甲酯以及非布司他的二聚体。结论该法为研究非布司他的稳定性及其可能的降解途径提供了参考。     

Cyclic hydroxamic acids: synthesis of 4-hydroxy-1H-1,2,4-triazolin-5-ones

Cyclic Hydroxamic Acids: Synthesis of 4-Hydroxy-1H-1,2,4-triazolin-5-ones A series of 4-hydroxy-1H-1,2,4-triazolin-5-ones ( 3 ) was prepared by cyclization of 2-acylhydrazine-1-carboxylic esters ( 4 ) with hydroxylamine or by reaction of arylhydroxamoyl chlorides with methyl hydrazinecarboxylate and cyclization of the hydrazidoxime intermediate 11 with base. None of the new compounds showed significant antibacterial or antimycotic activity.