微生物来源的HLE抑制剂N01WA-735E的研究

人白细胞弹性蛋白酶抑制剂为筛选炎症和癌症的重要靶点。应用白细胞弹性蛋白酶抑制剂高通量的筛选模型对数千株放线菌进行筛选,发现了阳性菌株N01 WA-735。首先通过形态学和化学分类学鉴定其为链霉菌属。采用有机溶剂提取、硅胶柱色谱、Sephadex LH-20柱色谱和结晶等方法对该菌株的发酵产物进行了分离纯化,得到活性单体化合物N01 WA-735E,通过对N01 WA-735E的理化性质和波谱数据分析,确定其结构与文献报道的化合物BE-52440A相同。该化合物对人白细胞弹性蛋白酶有很强的抑制活性,其IC50为3.02μmol/L。该化合物对人白细胞弹性蛋白酶的抑制活性国内外未见报道。     

一种白僵菌中MAO抑制剂的分离纯化和结构鉴定

本研究对前期筛选出的一株具有较强的单胺氧化酶(MAO)抑制活性的白僵菌菌株Ba02进行了液体培养;通过不同提取剂的提取效果比较,发现乙酸乙酯能较好地提取出该发酵液中单胺氧化酶抑制剂。通过活性指导下的色谱分离,从乙酸乙酯提取物中得到了一种深红色粉末状化合物。活性测定结果显示该化合物在15μg.mL-1时对MAO-A和MAO-B的抑制率分别为97.50%和95.34%。MS和NMR的鉴定结果表明该化合物为卵孢菌素(Oosporein)。虽然该化合物是一已知化合物,但其对单胺氧化酶的抑制活性尚属首次发现。     

一株海洋真菌Penicillium sp.QF046的细菌群体感应抑制剂的分离和鉴定

目的:从海洋真菌中筛选得到新型群体感应抑制剂,并对其进行活性评价。方法:首先利用紫色杆菌CV026指示菌株对真菌发酵粗提物进行活性筛选。其次通过18S r DNA序列比对进行菌种鉴定,同时采用硅胶柱色谱、凝胶柱色谱和高效液相色谱等技术并结合活性追踪检测分离纯化的活性化合物,再通过核磁质谱分析确定其结构。最后利用定量测定方法检测其在亚抑菌浓度下对紫色杆菌紫色菌素产量影响以及RT-PCR检测与QS调控相关基因的m RNA表达的影响。结果:从海藻共生菌中筛选到一株具有紫色杆菌群体感应抑制活性的海洋真菌Penicillium sp.QF046,其次级代谢产物中纯化到的活性化合物根据结构鉴定为一种星形曲霉毒素(asteltoxin)。该化合物对于紫色杆菌群体感应抑制浓度低于阳性对照化合物呋喃酮C30,同时抑制了群体感应相关基因m RNA水平的表达。结论:从海洋真菌Penicillium sp.QF046代谢产物中发现了一种抑制紫色杆菌群体感应的星形曲霉毒素,为进一步通过结构改造研发新型抗菌药物提供良好的前体化合物。     

黄河三角洲耐盐真菌Penicillium chrysogenum HK14-01的次生代谢产物

【目的】从黄河三角洲耐盐微生物的代谢产物中寻找具有抗菌和抗肿瘤活性的化合物。【方法】应用化学与生物活性相集成的筛选方法,从耐盐微生物中筛选获得代谢产物丰富并具有生物活性的目标菌株;通过高盐胁迫目标菌株,利用硅胶柱色谱、凝胶柱色谱和高效液相色谱等方法对发酵产物进行分离、纯化,运用波谱解析、钼靶X-射线单晶衍射分析、圆二色散谱(CD)和密度泛函数(DFT)-ECD的计算鉴定化合物的结构。【结果】从采自黄河三角洲的泥土样品中得到一株耐盐真菌HK14-01,鉴定为产黄青霉Penicilliumchrysogenum;从其发酵产物中分离鉴定了8个化合物:(2S,3R)-oxaline(1,主产物)、(3R,4R)-3,4,8-trihydroxy-3,4-dihydronaphthalen-1(2H)-one(2)、(Z)-N-(4-hydroxystyryl)formamide(3)、(E)-N-(4-hydroxystyryl)formamide(4)、emodin(5)、4-(2-hydroxyethyl)benzene-1,2-diol(6)、methyl 2-(4-hydroxyphenyl)acetate(7)和2-(4-hydroxy phenyl)acetonitrile(8);化合物1、3和4对大肠杆菌以及化合物1和5对金黄色葡萄球菌表现出抑菌活性,化合物5对P388细胞表现出微弱的细胞增殖抑制活性。【结论】首次确定了化合物2的绝对构型、首次报道了化合物1和2的CD数据;从黄河三角洲的耐盐微生物的次生代谢产物中可以得到活性化合物,这一区域的耐盐微生物资源值得深入研究。     

一株银杏内生真菌菌株的抑菌活性成分研究

从银杏叶柄分离筛选到具抗菌活性的内生真菌Colletotrichum.SP NTB-2菌株,利用硅胶柱色谱、制备高效液相色谱等方法在其发酵产物中分离到抗枯草芽孢杆菌、鼠伤寒沙门氏菌等具有广谱抑菌活性的化合物,经MS、NMR等波谱数据确认该活性成分为芹菜素-8-C-葡萄糖苷(apigenin-8-C-β-D-glucopyranoside),该化合物首次从真菌中分离得到。     

盐地碱蓬内生菌Neocamarosporium sp. ZLM-26次级代谢产物

本研究对盐地碱蓬内生菌Neocamarosporium sp. ZLM-26的活性次级代谢产物进行了挖掘。采用薄层色谱、硅胶柱色谱、高效液相色谱等分离方法,从该菌株大米培养基发酵产物的乙酸乙酯萃取物中分离得到6个单体化合物,经波谱学解析和文献数据对比,鉴定6个化合物分别为：5-butyl-6-(hydroxymethyl)-2H-pyran-2-one(1)、(7S)-xylariolide E(2)、(6S)-xylariolide D(3)、diaporpyrone A(4)、4-hydroxybenzaldehyde(5)和2-(2-hydroxyethyl) phenol(6)。分别采用CCK-8法和96孔板法评估了6个化合物的抗肿瘤和抗菌活性。结果显示,6个化合物(50 μmol/L)对胰腺癌细胞株SW1990、PANC-1的增殖无明显抑制作用;而化合物4对大肠杆菌有较好的增殖抑制活性,化合物5、6对铜绿假单胞菌有较好的增殖抑制活性。化合物1为1个新的天然产物,本研究首次报道了其核磁数据和抗菌活性。此外,化合物1–4均为首次从新凸轮孢菌属真菌中分离得到。     

北桑寄生内生真菌的分离及其次级代谢产物分析

首次对药用植物北桑寄生叶片中的内生真菌进行分离纯化,从中筛选出具有较高生物活性的菌株,鉴定此菌株并对其次级代谢产物进行初步分离。采用组织块法分离内生真菌,对其进行抗氧化活性和抑菌活性筛选;通过形态学和分子生物学方法鉴定其种属;运用柱色谱、重结晶等方法分离次级代谢产物,波谱学鉴定其结构。从北桑寄生叶片中分离纯化得到29株内生真菌,检测得到一株具有较高抗氧化和抑菌活性的菌株,鉴定为Alternaria alternata,从该菌次级代谢产物中首次分离得到3个单体化合物,分别为alternariol-5-O-methyl ether(1)、alternariol(2)、cis,cis-9,12-octadecadienoic acid(3)。化合物1和2具有较弱的抗氧化活性,化合物1和3表现出一定的抑菌活性。     

青海干旱生境土壤链霉菌次级代谢产物的分离鉴定及活性研究北大核心CSCD

对青海干旱生境土壤链霉菌Streptomyces pactum KIB-HL8液体发酵,应用硅胶柱色谱和高效液相色谱等方法进行分离和纯化,得到5个化合物,并用MS、NMR等方法对其结构进行解析,分别鉴定为N-乙酰酪胺(1)、N-乙酰色胺(2)、吡咯-2-甲酰胺(3)、Inthomycin C(4)和Inthomycin B(5)。对其抗真菌、细菌活性进行筛选,发现化合物4对金黄色葡萄球菌有抑制活性,化合物1和2对番茄灰霉病菌有抑制活性,化合物3对番茄早疫病菌有较强的抑制活性。     

青海干旱生境土壤链霉菌次级代谢产物的分离鉴定及活性研究

对青海干旱生境土壤链霉菌Streptomyces pactum KIB-HL8液体发酵,应用硅胶柱色谱和高效液相色谱等方法进行分离和纯化,得到5个化合物,并用MS、NMR等方法对其结构进行解析,分别鉴定为N-乙酰酪胺(1)、N-乙酰色胺(2)、吡咯-2-甲酰胺(3)、Inthomycin C(4)和Inthomycin B(5)。对其抗真菌、细菌活性进行筛选,发现化合物4对金黄色葡萄球菌有抑制活性,化合物1和2对番茄灰霉病菌有抑制活性,化合物3对番茄早疫病菌有较强的抑制活性。     

极地海洋真菌赛氏曲霉活性成分研究

通过对菌株r DNA-ITS序列和系统发育多样性进行分析,鉴定该菌株为赛氏曲霉;对赛氏曲霉用大米培养基进行固体发酵培养,对其发酵产物采用有机溶剂萃取、硅胶柱色谱层析、反相ODS柱色谱层析、薄层色谱层析、Sephadex LH-20凝胶柱色谱层析和制备型高效液相色谱等分离纯化手段进行分离,得到7个单体化合物。对分离得到单体化合物采用质谱、核磁共振氢谱、核磁共振碳谱、二维核磁共振等现代波谱技术对其进行结构鉴定;对单体化合物的MIC值进行测定,其中化合物L-1对耐甲氧西林金黄色葡萄球(MRSA)、耐甲氧西林表皮葡萄球菌(MRSE)有一定的抑菌活性,对大肠杆菌有明显的抑菌活性。     

Astragalar morphology of late Eocene anthropoids from the Fayum Depression (Egypt) and the origin of catarrhine primates

The phylogenetic relationships of the late Eocene anthropoids Catopithecus browni and Proteopithecus sylviae are currently a matter of debate, with opinion divided as to whether these taxa are stem or crown anthropoids. The phylogenetic position of Catopithecus is of particular interest, for, unlike the highly generalized genus Proteopithecus, this taxon shares apomorphic dental and postcranial features with more derived undoubted catarrhines that appear in the same region 1-2 Ma later. If these apomorphies are homologous and Catopithecus is a stem catarrhine, the unique combination of plesiomorphic and apomorphic features preserved in this anthropoid would have important implications for our understanding of the crown anthropoid morphotype and the pattern of morphological character transformations that occurred during the early phases of stem catarrhine evolution.Well-preserved astragali referrable to Proteopithecus, Catopithecus, and the undoubted early Oligocene stem catarrhine Aegyptopithecus have provided additional morphological evidence that allows us to further evaluate competing hypotheses of interrelationships among Eocene-Oligocene Afro-Arabian anthropoids. Qualitative observations and multivariate morphometric analyses reveal that the astragalar morphology of Proteopithecus is very similar to that of early Oligocene parapithecids and living and extinct small-bodied platyrrhines, and strengthens the hypothesis that the morphological pattern shared by these taxa is primitive within crown Anthropoidea. In contrast, Catopithecus departs markedly from the predicted crown anthropoid astragalar morphotype and shares a number of apomorphic features (e.g., deep cotylar fossa, laterally projecting fibular facet, trochlear asymmetry, mediolaterally wide astragalar head) with Aegyptopithecus and Miocene-Recent catarrhines. The evidence from the astragalus complements other independent data from the dentition, humerus and femur of Catopithecus that support this taxon's stem catarrhine status, and we continue to maintain that oligopithecines are stem catarrhines that constitute the sister group of a clade containing propliopithecines and Miocene-Recent catarrhines.     

中国异极衣科地衣二新记录种

该文综合运用形态学、解剖学和化学等方法对山东大型地衣进行分类研究,发现了两个中国新记录种,即德氏蜂窝衣(Heppia despreauxii)和多孢小极衣(Lichinella myriospora)。德氏蜂窝衣隶属于蜂窝衣属(Heppia),生于光线充足且裸露的土壤上,主要识别特征为下皮层缺失、子实层IKI+蓝色;多孢小极衣隶属于小极衣属(Lichinella),生于干燥的钙质岩石上,主要识别特征为其子实层IKI+酒红色变为蓝色。该文对这两个中国新记录种进行了详细描述,与近似物种进行了对比讨论,并且提供了其地衣体、子囊盘及其解剖特征图片。同时,该文还补充报道了白棋盘蜂窝衣(Heppia solorinoides)的有性繁殖结构特征和数据。蜂窝衣属和小极衣属均为山东新记录属。以上研究结果为中国异极衣科(Lichinaceae)地衣研究提供基础资料。     

藏药多刺绿绒蒿种子萌发特性研究

多刺绿绒蒿(Meconopsis horridula)为罂粟科绿绒蒿属一年生草本植物,是一种极具观赏价值和药用价值的高山植物,目前处于濒危状态,因此研究多刺绿绒蒿种子的萌发特性对其种子育苗及人工栽培具有重要意义。为了提高多刺绿绒蒿的种子发芽率,该研究以多刺绿绒蒿的种子为材料,分析了不同消毒剂、浸种时间、温度和外源植物激素对种子萌发特性的影响。结果表明:(1)最适消毒方法为75%乙醇1 min+3%H2O25 min,最适浸种时间为24 h,最适温度和光照条件为20℃/10℃(光照12 h/黑暗12 h),用无菌水浸种后的种子发芽率为49.67%。(2) GA_3100～600 mg·L~(-1)和NAA 5～30 mg·L~(-1)可以提高种子的发芽率、发芽势和发芽指数,缩短发芽启动时间和发芽持续时间,对种子的萌发有促进作用。(3) 6-BA 5 mg·L~(-1)和10 mg·L~(-1)对种子的萌发有一定的促进作用,但不显著,6-BA浓度≥15 mg·L~(-1)则抑制种子的萌发。(4)用GA3500 mg·L~(-1)浸种后的种子发芽指标最好,发芽率、发芽势和发芽指数分别为69.67%、33.00%、4.51,种子的发芽起始时间和发芽持续时间分别为10.67 d、11.67 d。     

scabrous Modifies Epithelial Cell Adhesion and Extends the Range of Lateral Signalling during Development of the Spaced Bristle Pattern in Drosophila

The role of scabrous (sca) in the evenly spaced bristle pattern of Drosophila is explored. Loss-of-function of sca results in development of an excess of bristles. Segregation of alternately spaced bristle precursors and epidermal cells from a group of equipotential cells relies on lateral inhibition mediated by Notch and Delta (Dl). In this process, presumptive bristle precursors inhibit the neural fate of neighbouring cells, causing them to adopt the epidermal fate. We show that Dl, a membrane-bound ligand for Notch, can inhibit adjacent cells, in direct contact with the precursor, in the absence of Sca. In contrast, inhibition of cells not adjacent to the precursor requires, in addition, Sca, a secreted molecule with a fibrinogen-related domain. Over-expression of Sca in a wild-type background, leads to increased spacing between bristles, suggesting that the range of signalling has been increased. scabrous acts nonautonomously, and we present evidence that, during bristle precursor segregation, Sca is required to maintain the normal adhesive properties of epithelial cells. The possible effects of such changes on the range of signalling are discussed. We also show that the sensory organ precursors extend numerous fine cytoplasmic extensions bearing Dl molecules, and speculate on a possible role for these structures during signalling.     

中国兰科二新记录种

兰科植物资源调查是掌握地区兰科本底资料的基础,对研究兰科植物的地理分布和资源多样性具有重要意义。该文报道了分别产自中国西藏自治区墨脱县和巴宜区的石豆兰属(Bulbophyllum Thou.)中国分布新记录种——尼泊尔大苞兰(B.raskotii J.J.Verm.,Schuit.&de Vogel)和曲唇兰属[Panisea(Lindl.)Steud.]中国分布新记录种——林芝曲唇兰(P.panchaseensis Subedi)。此二新记录种均生长在海拔约2000 m的常绿阔叶林中的树干或岩壁上。此外,还提供了二新记录种的形态特征描述和彩色图片等信息,并附有国产曲唇兰属的分种检索表。该研究结果扩充了我国兰科植物的记录,为我国兰科植物多样性和保护研究提供了新资料。     

Stratigraphy, artefact industries and hominid associations for Sterkfontein, member 5

A revised stratigraphy for the early hominid site of Sterkfontein (Gauteng Province, South Africa) reveals a complex distribution of infills in the main excavation area between 2.8 and 1.4 m.y.a, as well as deposits dating to the mid to late Pleistocene. New research now shows that the Member 4 australopithecine breccia (2.8-2.6 Ma) extends further west than was previously thought, while a late phase of Member 4 is recognized in a southern area. The artefact-bearing breccias were defined sedimentologically as Member 5, but one supposed part of these younger breccias, the StW 53 infill, lacks in situ stone tools, although it does appear to post-date 2.6 Ma when artefacts first appear in the archaeological record. The StW 53 hominid, previously referred to Homo habilis, is here argued to be Australopithecus. The first artefact-bearing breccia of Member 5 is the Oldowan Infill, estimated at 2-1.7 Ma. It occupies a restricted distribution in Member 5 east and contains an expedient, flake-based tool industry associated with a few fossils of Paranthropos robustus. An enlarged cave opening subsequently admitted one or more Early Acheulean infills associated in Member 5 west with Homo ergaster. The artefacts attest to a larger site accumulation between ca. 1.7 and 1.4 Ma, with more intensive use of quartzite over quartz and a subtle but important shift to large flakes and heavier-duty tools. The available information on palaeoenvironments is summarized, showing an overall change from tropical to sub-tropical gallery forest, forest fringe and woodland conditions in Member 4 to more open woodland and grassland habitats in the later units, but with suggestions of a wet localized topography in the Paranthropus -bearing Oldowan Infill.     

Essential amino acids of starch synthase IIa differentiate amylopectin structure and starch quality between <Emphasis Type="Italic">japonica</Emphasis> and <Emphasis Type="Italic">indica</Emphasis> rice varieties

Four amino acids were variable between the ‘active’ indica-type and ‘inactive’ japonica-type soluble starch synthase IIa (SSIIa) of rice plants; Glu-88 and Gly-604 in SSIIa of indica-cultivars IR36 and Kasalath were replaced by Asp-88 and Ser-604, respectively, in both japonica cultivars Nipponbare and Kinmaze SSIIa, whereas Val-737 and Leu-781 in indica SSIIa were replaced by Met-737 in cv. Nipponbare and Phe-781 in cv. Kinmaze SSIIa, respectively. The SSIIa gene fragments shuffling experiments revealed that Val-737 and Leu-781 are essential not only for the optimal SSIIa activity, but also for the capacity to synthesize indica-type amylopectin. Surprisingly, however, a combination of Phe-781 and Gly-604 could restore about 44% of the SSIIa activity provided that Val-737 was conserved. The introduction of the ‘active’ indica-type SSIIa gene enabled the japonica-type cv. Kinmaze to synthesize indica-type amylopectin. The starch in the transformed japonica rice plants exhibited gelatinization-resistant properties that are characteristic of indica-rice starch. Transformed lines expressing different levels of the IR36 SSIIa protein produced a variety of starches with amylopectin chain-length distribution patterns that correlated well with their onset temperatures of gelatinization. The present study confirmed that the SSIIa activity determines the type of amylopectin structure of rice starch to be either the typical indica-type or japonica-type, by playing a specific role in the synthesis of the long B₁ chains by elongating short A and B₁ chains, notwithstanding the presence of functional two additional SSII genes, a single SSI gene, two SSIII genes, and two SSIV genes in rice plants.     

不同光质对白及组培苗生长及光合特性的影响

白及的自然繁殖率极低,组培育苗是其种苗繁殖的主要方式之一。为探索提高白及组培育苗质量及缩短育苗周期的高效人工光环境,该文以紫花白及(Bletilla striata)为试验材料,研究LED光质对白及组培苗的生长和光合特性的影响。结果表明:提高红蓝光组合中的蓝光占比,有利于促进白及组培苗的生长和生物量的积累,而白及的球茎大小与红光的占比呈正相关;在红蓝组光合中增加25%的绿光(2R1B1G),可显著提高白及叶片的叶绿素含量和净光合速率,促进组培苗根系和叶片的生长。综上结果表明,2R1B1G处理下的白及组培苗株高、茎粗、叶绿素含量、净光合速率和根系发育均表现出最佳优势,2R1B1G处理的LED光谱可推荐作为白及组培育苗的光质配方。     

荨麻科三新种

该文描述了荨麻科三新种:(1)自中国重庆市发现的荨麻科荨麻属一新种,城口荨麻。此种与异株荨麻有亲缘关系,区别特征为此种的茎被少数刺毛,叶片多为心形,雄、雌花序均不分枝,瘦果在中央稍凹陷。(2)自中国广西发现的荨麻科赤车属一新种,来宾赤车。此种与特产云南东南部的富宁赤车相近缘,与后者的区别在于本种茎的毛开展或向上弯曲,叶片长椭圆形,基部斜楔形,雌花具3~4枚花被片,其中1~2枚较大花被片在背面顶端具一长筒状突起。(3)自缅甸北部发现的荨麻科楼梯草属一新种,克钦楼梯草。此种在体态上与骤尖楼梯草甚为相似,与后者的区别在于本种的每一茎节具正常叶和一退化叶,托叶狭披针状条形和无脉,雌总苞苞片无角状突起,雌小苞片较大,呈楔状长圆形,雌花具一小花被片,以及雌蕊具一宽倒卵球形柱头。     

茉莉酸甲酯对广藿香JA信号转导途径及倍半萜合成途径关键基因表达的影响

分析外源性茉莉酸甲酯对广藿香JA信号转导途径关键基因JAZ2、MYC2、COI1及倍半萜合成途径关键基因PTS、FPPS、SQLE表达的影响,为深入研究茉莉酸甲酯调控广藿香JA信号转导途径及倍半萜合成途径的分子机制奠定基础。该文分别用0.10和0.25 mmol·L~(-1)的MeJA喷施广藿香叶片,于处理后的0、2、6、12、24、48、72 h摘取叶片,运用实时荧光定量PCR对JAZ2、MYC2、COI1、PTS、FPPS、SQLE基因的表达量进行检测。结果表明:0.10和0.25 mmol·L~(-1)的MeJA对广藿香JA信号转导途径JAZ2、MYC2、COI1及倍半萜合成途径PTS、FPPS、SQLE基因表达均有不同程度的促进作用,其中对JAZ2基因表达影响最显著。0.10mmol·L~(-1)MeJA溶液处理2 h时,JAZ2表达量上调13.52倍; 0.25 mmol·L~(-1)MeJA溶液处理48 h时,JAZ2表达量上调19.09倍。JA信号转导途径关键基因JAZ2与倍半萜合成途径关键基因FPPS存在极显著正相关关系。综上结果表明MeJA溶液可诱导广藿香JAZ2、MYC2、COI1、PTS、FPPS、SQLE基因的表达,且不同浓度MeJA对基因表达有着不一样的影响; JAZ2是JA信号转导途径里响应MeJA诱导的主要基因,其可激活倍半萜合成途径FPPS基因的协同表达,进而影响广藿香醇等倍半萜合成。