人载脂蛋白A-Ⅰ半胱氨酸突变体的二级结构和脂质结合能力的比较

为探讨人载脂蛋白A-Ⅰ(apoA-Ⅰ,apolipoproteinA-Ⅰ)α螺旋不同位点的半胱氨酸突变后,对蛋白二级结构和脂质结合能力的影响,利用定点诱变技术构建apoA-Ⅰ的天然半胱氨酸突变体apoA-ⅠMilano(R173C),及其它α螺旋片段上的半胱氨酸突变体,分别为apoA-Ⅰ(S52C),apoA-Ⅰ(N74C),apoA-Ⅰ(L107C),apoA-Ⅰ(K129C),和apoA-Ⅰ(L195C).观察比较各种野生型及突变apoA-Ⅰ单体蛋白的α螺旋含量和二级结构稳定性及其脂质结合能力.结果显示,野生型apoA-Ⅰ,apoA-Ⅰ(S52C),apoA-Ⅰ(N74C),apoA-Ⅰ(L107C),apoA-Ⅰ(K129C),apoA-ⅠMilano和apoA-Ⅰ(L195C)的α螺旋含量分别为54±4%,49±4%,50±2%,51±6%,56±4%,52±3%,和54±1%,各种蛋白的α螺旋含量无显著性差异(P>0.05).野生型apoA-Ⅰ的变性标准自由能(ΔG0D)为10.5kJ/mol;apoA-Ⅰ(S52C)和apoA-ⅠMilano的ΔG0D比野生型低2.1kJ/mol;而apoA-Ⅰ(K129C)的ΔG0D比野生型apoA-Ⅰ高1.6kJ/mol.与野生型apoA-Ⅰ相比,apoA-Ⅰ(K129C)和apoA-Ⅰ(L195C)两个突变体与脂质结合能力明显下降(P<0.05),而其它半胱氨酸突变体(包括apoA-ⅠMilano)在脂质结合动力学方面与野生型apoA-Ⅰ无明显差异.以上结果提示,不同位点发生的半胱氨酸突变对apoA-Ⅰ单体蛋白的α螺旋含量无明显影响,但对蛋白的二级结构稳定性和脂质结合能力影响不尽相同.     

Study on the Chemical Constituents of Salvia prionitis

Tanshinone Ⅱ-A (Ⅱ), tanshinone Ⅰ (Ⅲ), cryptotanshinone (Ⅳ), β-sitosterol and 4,5- seco-5,10-friedo-abieta-3,5(10), 6,8,13-pentaene-ll.12-dione (Ⅰ) which was called saprorthoquinone as a natural product directly isolated from the plant, were isolated from the root of Salvia prionitis Hance for the first time. (Ⅰ) showed a strong cytotoxicity against P388 leukemia cell in vitro.     

高糖低脂膳食对健康大学生血清apoAⅠ和apoB100水平及apoAⅠ/apoB100的影响

高脂血症是典型的多因素、多基因疾病.为探讨青年人性别、体质指数(BMI)与高糖低脂膳食之间的相互作用及其与血清脂质、载脂蛋白apoAⅠ,apoB100及apoAⅠ/apoB100的关系,本研究招募了27名男性（22.96±1.95岁）及29名女性（22.83±1.67岁）健康大学生志愿者,给予7 d平衡膳食和6 d高糖低脂膳食,分别在第1 d,第8 d及第14 d晨取空腹血,测定血清甘油三脂（TG）、总胆固醇（TC）、葡萄糖（Glu）、高密度脂蛋白胆固醇（HDL-C）、非低密度脂蛋白胆固醇（NLDL-C）、apoAⅠ及apoB100,计算低密度脂蛋白胆固醇（LDL-C）含量和apoAⅠ/apoB100比值.组分分析发现,高糖低脂膳食后,TG、HDL-C显著升高(P ＜0.01）,TC、LDL-C显著降低（P <0001）.同时,apoAⅠ及apoAⅠ/apoB100显著增加（P ＜0.05）,apoB100没有明显变化.性别分组分析发现,高糖低脂膳食后,男性apoAⅠ/apoB100显著增加（P ＜0.05）,apoAⅠ、apoB100没有显著改变;女性apoAⅠ、apoB100、apoAⅠ/apoB100均无显著变化.BMI分组分析发现,在14≤BMI＜19、19≤BMI＜23和23≤BMI＜29三组中,仅14≤BMI＜19组apoAⅠ（P <0.05）及apoAⅠ/apoB100（P ＜0.01）显著升高.但男性14≤BMI＜19组和23≤BMI＜29组apoAⅠ显著增加（P <0.05）,19≤BMI＜23组apoB100则显著降低（P ＜0.05）,apoAⅠ/apoB100在14≤BMI＜19组和19≤BMI＜23组显著增加（P ＜0.01）.而女性仅在14≤BMI＜19组apoAⅠ/apoB100显著增高（P ＜0.05）.结果表明,在健康大学生中,性别、BMI、高糖低脂膳食之间的相互作用在高糖诱导的高甘油三酯血症血清apoAⅠ,apoB100及apoAⅠ/apoB100的改变中起着重要的作用.     

豆柄瘤蚜茧蜂触角感受器的扫描电镜观察(英文)

利用扫描电镜对豆柄瘤蚜茧蜂Lysiphlebus fabarum的触角感受器进行了观察, 发现有7 种感受器, 分别为毛形感受器、刺形感受器Ⅰ型、刺形感受器Ⅱ型、锥形感受器、腔锥形感受器Ⅰ型、腔锥形感受器Ⅱ型和板形感受器。毛形感受器是数量最多的感器; 除了腔锥形感受器Ⅱ型只在雌虫触角发现外, 雌、雄触角感受器的类型和结构没有较大的差别, 并且腔锥形感受器Ⅱ是数量最少的感器。     

虎纹捕鸟蛛毒素-Ⅰ突变体A1Y-HWTX-Ⅰ的固相合成和生物学活性测定

用芴甲氧羰基 (Fmoc)固相多肽合成的方法在自制自动蛋白质化学工作站上合成了用酪氨酸 (Y)替代虎纹捕鸟蛛毒素 - (HWTX- )第一位丙氨酸 (A1 )的突变体 A1 Y- HWTX- .合成的突变体用 Edman降解和电喷雾质谱法进行鉴定 .活性分析结果证明 ,合成的 A1 Y- HWTX- 在含有谷胱甘肽的缓冲体系中氧化折叠后显示出与天然 HWTX- 完全相同的生物学活性 ,提示 Y替代 HWTX- 的 A1后并不明显影响 HWTX- 的活性部位和空间构象 ;A1与 HWTX- 生物学活性无关 .此外 ,将 Y引入 HWTX- 分子有助于利用碘标记方法研究 HWTX- 的作用机制     

Effects of Water Stress on Chlorophyll-Protein Complexes in Wheat Chloroplasts

The excitation energy transfer from light harvesting chlorophyll protein complexes to PS Ⅱ was inhibited under water stress. The contents of iriternal antennae chlorophyll-protein complexes of PS Ⅱ (CPa), light harvesting chlorophyll-protein complexes of PS Ⅱ (LHC Ⅱ ), light harvesting chlorophyll-protein of PS Ⅰ (LHC Ⅰ ) and chlorophyll a protein complex of reaction center of PS Ⅰ were decreased by water stress. The decrease of chlorophyll-protein complexes of PS Ⅱ was greater than that of PS Ⅰ . It was indicated that the amount of 25 kD polypeptide of LHC Ⅱ in particular, as well as that of 43 and 47 kD polypeptides of CPa, and 21 kD polypeptide of LHC Ⅰ , were reduced by water stress.     

二种大实蝇的PCR-RFLP快速鉴定方法

应用PCR-RFLP技术,对我国部分地区发生分布的蜜柑大实蝇和橘大实蝇开展了分子生物学鉴定方法研究。结果表明,利用4组引物对目标实蝇的COⅡ和ITS1基因进行PCR扩增,并借助MnlⅠ,MseⅠ,AseⅠ,DraⅠ和SspⅠ等5种限制性内切酶对扩增产物进行酶切,能从多个途径把2种大实蝇区分开。所建立的方法不受目标实蝇食物源、地理来源和标本保存条件的影响,对不同虫态和不同性别的个体均适用,可在生产和检疫实践中对蜜柑大实蝇和橘大实蝇进行快速鉴定。     

纹带棒状杆菌耐药特征研究

分析我国山东地区临床分离的纹带棒状杆菌对常用药物的敏感性,并对其耐药机制进行探讨。收集该省某三甲医院临床样本,用哥伦比亚血平板培养基对纹带棒状杆菌进行分离培养,用微量肉汤稀释法检测12种常用抗生素对纹带棒状杆菌的最低抑菌浓度(minimal inhibitory concentration, MIC)。采用聚合酶链式反应(polymerase chain reaction,PCR)对耐药菌株的耐药基因[aph(3”)-Ⅰb、aph(6)-Ⅰd、aac(6’)-Ⅰb, tetW, ermX, gyrA]进行扩增、测序比对,以探讨相关的耐药机制。通过实时荧光定量PCR(quantitative real-time PCR, qPCR)对耐药基因ermX、tetW进行定量分析,采用公式2^－ΔΔCt计算基因相对表达量差异倍数。结果显示,共分离出纹带棒状杆菌83株,且均为多重耐药菌。对万古霉素、利奈唑胺表现为完全敏感;对红霉素、环丙沙星、克林霉素表现出完全耐药,对四环素的耐药率为86.7%(72/83),对庆大霉素的耐药率为38.6%(32/83);ermX基因的检出率为100%(83/83),tetW基因的检出率为88.0%(73/83),aph(3”)-Ⅰb基因的检出率为36.1%(30/83),aph(6)-Ⅰd基因的检出率为37.3%(31/83),aac(6’)-Ⅰb基因的检出率为15.7%(13/83)。ermX和tetW基因的相对表达量均有所变化,但变化不明显。内在型耐药(cMLS)是菌株对红霉素耐药的潜在机制。结果提示,本研究调查医院的纹带棒状杆菌耐药严重,耐药谱较为广泛,须引起医院和实验室的重视。     

Separation and Identification of Chemical Constituents of Dysosma majorense(Gagn.)Hsiao et Y. H. Chen,nov comb

Ten compounds, namely physcion (Ⅰ), podophyllotoxone (Ⅱ), isopicropodophyllone (Ⅲ), picropodophyllone (Ⅳ), 4'-demethyl-podophyllotoxone (Ⅴ), dehydropodo- phyllotoxin (Ⅵ), diphyllin (Ⅶ), picropodophyllin (Ⅷ), podophyllotoxin (Ⅸ) and 4'-demethylpodophyllotoxin (Ⅹ), were separated from Dysosma majorense (Gagn.) Hsiao et Y. H. Chen, nov comb. Compound Ⅳ was first isolated from natural source and anthraquinone Ⅰ was first isolated from genus Dysosma. Ⅴ, Ⅷ and Ⅹ showed strong acttve inhibited against P388.     

Studies on the Chemical Constituents of Xylanche himalaica

Six compounds were isolated from the tuber of Xylanche himalaica (Hook. f. et Thorns.) G. Beck Based on the physico-chemical constants, spectral analysis (IR, MS, 1H-NMR, 13C-NMR)and preparation of the derivative, they were identified as 3-epi-acetoxyurs-12-en-28-al (Ⅰ), ursolic acid (Ⅱ), 3-epi-ursolic acid (Ⅲ), (+)-pinoresinol (Ⅳ), (+)-pinoresinol monoglucoside (Ⅴ) and daucosterol (Ⅵ). Ⅰis a new compound.     

Studies on the Constltuents of the Flavonoids from the Leaves of Typha angustifolia L.

Six flavonoids were isolated from the leaves of Typha angustifolia L. On the basis of spectroscopic (IR, UV, MS, 1HNMR and 13CNMR) analysis, they were identified as quercetin-3,3'-dimethyl ether (TF-Ⅰ), isorhamnetin (TF-Ⅱ), quercetin (TF-Ⅲ), quercetin-3,3' dimethyl ether-4'-O-β-D-glucoside (TF-Ⅳ), isorhamnetin-3-O-β-galactoside (TF-Ⅴ), and isorhamnetin-3-O-neohesperidoside (TF-Ⅵ). Compounds TF-Ⅰ and TF-Ⅴ were found in the genus of Typha for the first time.     

The Chemical Principles from the Female lnftorescences of Typha angustata

Seven crystalline compounds have been isolated from the female inflorescences of Typha angustata Bory et Chaub. They were identified as vanillic acid (Ⅰ), E-p-hydroxy- cinnamic acid (Ⅱ), Protocatechuic acid (Ⅲ), E-Pro-penoic acid-3- (4-hydroxyphenyl)- 2,3-dihydrohypropyl ester (Ⅳ), Succinic acid (Ⅴ), p-hydroxybenzaldehyde (Ⅵ) and D-mannitol (Ⅶ). (Ⅳ) is a new compound. (Ⅰ), (Ⅱ), (Ⅲ) and (Ⅶ) were attained for the first time from Typhaceae.     

微紫青霉CBHⅠ酶纤维素结合结构域在大肠杆菌中的分泌型表达及性质研究

为研究纤维素酶纤维素结合结构域的结构与功能 ,进而深入了解天然纤维素的生物降解机制和提高纤维素酶的生物工艺学价值 ,采用 PCR技术体外扩增了携带微紫青霉外切葡聚糖纤维二糖水解酶 ( CBH ) CBD编码区的 DNA片段 ,将 CBD编码区 DNA片段插入带有 Erwiniacarotovora pe1 B前导肽序列的大肠杆菌质粒 p KK- tac- new上进行了表达 .携带微紫青霉 CBDCBH 编码区的大肠杆菌重组菌株 DH5α( p KK- tac- new- 8)产生有活性的分泌型 CBDCBH 蛋白 .SDS-PAGE检测显示所产生的 CBDCBH 蛋白分子量约 1 0 .8k D.在 IPTG诱导下 ,该菌株所产生的CBDCBH 蛋白含量达 45.2 mg/L,且 90 %以上的 CBD蛋白分泌到培养物上清液中 .结晶纤维素 CF-1 1溶液经 CBDCBH 处理后 ,浊度比对照提高了 1 2 8.9% ,天然棉花纤维结构经 CBDCBH 处理后产生一定程度的非水解性降解作用 ,表明微紫青霉 CBDCBH 具有解聚天然结晶纤维素的作用 .     

皖琅琊山自然保护区大型真菌群落多样性

对安徽省琅琊山自然保护区大型真菌的群落多样性进行了研究。对该区内设置的样地Ⅰ(针阔混交林)、样地Ⅱ(常绿-落叶阔叶混交林)、样地Ⅲ(落叶阔叶林)、样地Ⅳ(琅琊榆-刺槐林)和样地Ⅴ(竹林)共5种具有代表性的植物群落内的大型真菌的种类和数量进行了调查。选用了物种丰富度(R)、Shannon-Wiener多样性指数(H′)、Pielou均匀度指数(E)和优势度曲线(K-dominance)等指标,对该区大型真菌的群落多样性进行了测定。结果表明,大型真菌的分布与植物群落类型有着密切关系。R的变化趋势为样地Ⅱ样地Ⅰ样地Ⅲ样地Ⅳ样地Ⅴ;H′的变化趋势是样地Ⅰ样地Ⅱ样地Ⅲ样地Ⅳ样地Ⅴ;E的变化趋势是样地Ⅰ样地Ⅲ样地Ⅱ样地Ⅳ样地Ⅴ。另外,季节变化对大型真菌的分布也有较大的影响。秋季大型真菌出现的种类及个体数量较高,R和H′高于春季,而E值却相反。选用的群落多样性指标能较客观地反映该地区大型真菌群落的组成,并揭示不同群落间的关系。     

Studies on Chemical Constituents of Fritillaria yuminensis

Six compounds were isolated from the bulbs of Fritillaria yuminensis X. Z. Duan. They were elucidated as 5α, 14α-cevanine-3α-hydroxy-6-one ( Ⅰ ), 5α, 14α-cevanine-3-one-6β-O-β-D-glucoside ( Ⅱ ), imperialine ( Ⅲ ), delavinone ( Ⅳ ), tortifolisine ( Ⅴ ) and adenosine( Ⅵ ) by means of spectral analysis and chemical reaction. They all were firstly isolated from this plant. Among them, compound Ⅰ and Ⅱ, named yubeinine and yubeiside respectively, were new compounds.     

Characterization of a New Chlorophyll-Protein Complex and Studies on Some Properties of Other Chlorophyll-Containing Bands

1. The chlorophyll-protein complexes of sun plant spinach and shade plants Malaxis monophyllos (L.) Sw. and Chlorophytum comosum (Thunb.) Jacques were resolved by SDS-PAGE at lower temperature (2—4 ℃). Besides 8 chlorophyll-containing bands Ⅰa, Ⅰb, Ⅰc, Ⅱa, Ⅱb, Ⅱc, Ⅲ and Ⅳ mentioned in our previous paper (Chu et al., 1980), three more small chlorophyll-containing bands were also observed. Among these small bands Ⅱa which often appeared between Ⅰc and Ⅱa looked like a oligomer of LHCP complex according to its properties in colour, absorption spectrum and fluorescence emission etc. 2. When electrophoresis was carried out at lower temperature (2—4 ℃), the quantity of free pigments (Ⅲ) was obviously lower, while the relative quantities of LHCP Ⅱa, Ⅱb and PS Ⅱ’s band (Ⅳ) were apparently higher than those carried out at higher temperature (12—15 ℃). At lower temperature three bands of Ⅰ could be resolved in shade plants M. monophyllos and C. comosum, and at higher temperature there was only one band of Ⅰ (Ⅰc). But at higher temperature three bands of Ⅰ could be resolved in sunflower. 3. The percentage of LHCP complexes of shade plant M. monophyllos in total amount of chlorophyll (57%) was obviously higher than that of sun plant spinach (43%). The percentage of complexes Ⅰ of sun plant spinach in amount of total chlorophyll (27%) was obviously higher than that of shade plant M. monophyllos (14%). The relative quantity among three bands of Ⅰ in different Plants is different. 4. The chl a/b ratio of LHCP bands of shade plants were lower than that of corresponding bands of sun plants. The chl a/b ratio of Ⅱa of M. monophyllos was 1.1, Ⅱc, 1.2; but that of Ⅱa of spinach was 1.4, Ⅱc, 1.66.     

我国32种鸟类DNA条形码分析

DNA条形码是一种分子分类方法,近年来在物种鉴定方面得到迅速的发展和应用.本研究分析了我国27属32种鸟类(61只)的线粒体细胞色素c氧化酶亚基Ⅰ(COⅠ)基因的条形码片段,分别用阈值法、聚类法和诊断核苷酸进行了分析,探究DNA条形码鉴定我国鸟类的准确性.结果显示,种内CO Ⅰ序列变异很小,种间存在较多的变异位点,种间的遗传距离显著大于种内的遗传距离,DNA条形码序列能够鉴定所有鸟类.     

Study on the Isolation,Purification and Antioxidation Properties of Polysaccharides from Spirulina maxima

The emde polysaccharide was extracted from Spirulina maxima with hot water, and precipitated by ethanol after depmteinization. Two portions of refined polysaccharides (SPS I and SPS H ) were prepared after further purification on DEAE-Sephadex A-25 column chromatography, and their homogeneity was examined with Sephadex G-150 column chromatography. The ultraviolet spectm showed their characteristic absorption at 195.00 mn. In order to estimate the antioxidation activity of SPS Ⅰ and SPS Ⅱ, three systems of generating superoxide radical (O2-), lipid radical (R') and hydroxyl radical (OH') respectively in vitro were designed. The results showed that both SPS Ⅰ and SPS Ⅱ from S. maxima had significant capacity of scavenging OH' ( P < 0.05), but no effect on O2 ( P > 0.1 ); and that SPS Ⅰ could scavenge R' under lower concentration of polysaccharides (P < 0.05), while the capacity of scavenging R' of both SPS Ⅰ and SPS Ⅱ decreased in higher concentration ( P > 0.2). These results demonstrated that the significant antioxidation activity of polysaccharides from S. maxima was focused on scavenging OH', the most highly reactive one of the oxygen radicals.     

Studies on the Alkaloids of Cyclea hainanensis Merr

Seven alkaloids have been isolated from the over ground parts of Cyclea hainanensis Merr (Menispermaceae) grown in Hainan is]and. Six of them are identified to be (-) curine (Ⅰ), (+)-4"-O-methylcurine (Ⅱ), hayatine (Ⅲ), d-isochondodendrine (Ⅳ), α-cyclanoline (Ⅴ), and a new quaternary alkaloid named α-hainanine (Ⅵ) respectively. Alkaloid (Ⅶ) is being identified. Dimethiodide and Dimethochloride derivatives of alkaloids (Ⅰ)—(Ⅲ) show neuromuscular blocking activity, but disochondodendrine hydrochloride possesses distinct analgesia.     

地中海实蝇幼虫分子鉴定

通过对从秘鲁进口的葡萄中截获实蝇类幼虫进行ITS区和线粒体COⅠ,COⅡ,COⅢ、ND5基因序列的扩增和测序,并与GenBank中对应的序列进行比对,结果表明,截获样品ITS区序列和地中海实蝇Ceratitis capitata(Wiedemann)同源性为95·16%(其中ITS1为99·52%,ITS2为86·2%),线粒体COⅠ,COⅡ,COⅢ,ND5基因序列和地中海实蝇C.capitata同源性为100%,99·9%,99·5%,99·8%;基于COⅠ序列构建的系统发育树中,幼虫样品和地中海实蝇最为接近。根据序列分析和系统发育关系分析的结果,将截获的实蝇类幼虫鉴定为地中海实蝇C.capitata。