眼虫Astasia longa类核纤层蛋白基因的初步研究

利用PCR和克隆测序技术,对眼虫Astasia longa的核纤层蛋白（lamin）基因进行了研究。参考多种相对较低等多细胞动物的已知序列,设计出扩增lamin基因尾部区的引物,扩增获得两个主要片段：序列Ⅰ（650bp）和序列Ⅱ（797bp）。测序分析表明,序列Ⅱ包含序列Ⅰ,并具有lamin基因尾部特征（编码“CaaX“序列的四种密码子 终止密码子）的序列片段。     

腐生型眼虫Astasia longa两种TIM同工酶cDNA的克隆和分析

利用 3′ RACE和 5′ RACE技术 ,从腐生型眼虫长变胞藻 (Astasialonga)克隆了磷酸丙糖异构酶(TIM)的两个同工酶cDNA全序列。分析表明 :它们分别编码定位于细胞质的胞质型TIM (cTIM)和定位于质体的质体型TIM (pTIM) ;后者的N端具有引导该酶定位到质体中去的典型“前导序列”。根据这些事实我们推测腐生型眼虫A .longa质体中可能存在功能性的TIM ,并进一步认为该质体可能不只是一般意义上的“叶绿体退化的残迹” ,而仍是一种至少有TIM参与其代谢活动的功能性细胞器     

Mitochondrial ribosomes of the phytoflagellata Astasia longa

The physico-chemical properties of ribosomes and rRNA isolated from the mitochondria of the phytoflagellata Astasia longa were studied. It was shown that the mitochondrial ribosomes of A. longa have the sedimentation coefficient of 81S (those of the cytoplasm-82S); upon a decrease of Mg2+ concentration in the medium they dissociate into subparticles with sedimentation coefficients of 60 and 45S. The relative protein content in the mitochondrial ribosomes of A. longa is equal to 42% (rho = 1,60 g/cm3), that of cytoplasmic ribosomes-49%. The molecular weights of mitochondrial rRNA are equal to 1,05 . 10(6) and 0,71 . 10(6) and differ from those for cytoplasmic rRNA (1,32 . 10(6) and 0,94 . 10(6)). It was shown that the GC-content in mitochondrial rRNA is equal to 32,0 mol. %, that in cytoplasmic rRNA-55,9 mol. %. Thus, the mitochondrial ribosomes of A. longa differ in some of their properties from both procaryotic and eucaryotic ribosomes and are probably related to a special type of mitochondrial ribosomes.     

Photodynamically induced chemoresponses of the colorless flagellate,Astasia longa,in the presence of riboflavin

In the presence of the photosensitizer riboflavin, Astasia accumulates in illuminated fields at high fluence rates. The quenchers of riboflavin excited states, NaN₃ and KI, abolish the photodynamic effect of riboflavin. Crocetin, a ¹O₂ quencher, does not influence the photodynamic action of riboflavin while 1,4-benzoquinone very strongly depresses its effect. This indicates a type I pathway forming H₂O₂ as a photoproduct. The photodynamic effect is abolished by the addition of 10^-5 M catalase which breaks down H₂O₂. Astasia shows chemoaccumulations around the opening of a capillary filled either with riboflavin (under high intensity irradiation) or H₂O₂ which proves the hypothesis that the photobehavioral response in the presence of riboflavin is based on a chemoresponse toward H₂O₂, produced when the dye is irradiated. The accumulation around the capillary opening is not due to a direct chemotactic movement of cells but rather to a chemophobic response which prevents the cells from swimming away from the chemoattractant.     

Ubiquinone-9 of the flagellates Crithidia oncopelti and Astasia longa

The content of ubiquinones (Co Q) of the Astasia longa and Crithidia oncopelti protozoa was studied. The protozoa were grown on an artificial nutrient broth. The cells were separated, washed, freeze-dried, and refluxed with KOH and pyrogallol in ethanol media. The hydrolyzate was concentrated. The residue was stored at -20 degrees and filtered. An ubiquinone fraction was isolated from the filtrate by TLC on silica gel. Identification of the ubiquinone homologues was carried out by reverse phase TLC and mass spectrometry. Ubiquinones were quantitated with respect to the difference in the density between the oxidized and reduced forms of Co Q at 275 nm. The A. longa and C. oncopelti flagellates were shown to contain ubiquinone-9 (Co Q9) at a concentration of 0.48 and 1.14 mumole/g dry cells, respectively. The higher Co Q level in zooflagellates as compared to that in phytoflagellates is discussed.     

姜黄根茎内生真菌区系分析

目的了解姜黄植物根茎中内生真菌群落组成和生态分布规律。方法采用表面消毒法分别于春、冬季从姜黄植物根茎中分离内生真菌,通过形态特征和基于ITS序列的系统发育分析初步确定其分类地位。结果分离获得51株内生真菌(春季33株、冬季18株),初步鉴定其分别归于5个纲、7个目、8个科、8个属(Fusarium,Gibberel-la,Alternaria,Phomopsis,Diaporthe,Nectria,Botryosphaeria,Mucor),其中镰刀菌属(Fusarium,51.0%)和赤霉属(Gibberel-la,17.6%)为优势菌群;春季分离的内生真菌分属于7个属(分离率为82.5%),而冬季的内生真菌仅归入4个属(分离率为45.0%)。结论姜黄植物中内生真菌具有较丰富的物种和系统发育多样性,在类群组成和分布上存在季节性差异,某些内生真菌(Fusariumsp.)具有宿主偏好性。     

Studies on Mitochondrial Proteins. II. Localization of Components in the inner membrane labelling with diazobenzenesulfonate,a non-penetrating probe

The topography of the inner membrane of rat liver mitochondria was studied using a probe, diazobenzenesulfonate, which interacts preferentially with surface components. Inner membranes were examined both in a native orientation as found in the intact mitochondrion or in an inverted state as found in isolated inner membranes prepared by sonication.Enzyme inactivation as a consequence of diazobenzenesulfonate labeling was employed to determine the localization of a number of inner membrane activities. In inner membranes labeled on the outer surface, NADH and succinate oxidation were strongly inhibited while ATPase and $\text{ascorbate}\text{-N,N,N′,N′-}\text{tetramethyl}\text{-p-}\text{phenylene-diamine}$ (TMPD) oxidase activities were unaffected. In inner membranes labeled on the inner surface. ATPase and succinate oxidation were inactivated while NADH oxidation and ascorbate-TMPD oxidase were unaffected. Succinate dehydrogenase was inhibited only by labeling the inner surface while NADH dehydrogenase was inhibited to a similar extent by treatment of either surface.Sodium dodecylsulfate-polypeptides (66 000 and 26 000) on the outer surface of the inner membrane and five polypeptides (80 000, 66 000, 51 000-48 000, and 26 000) on the inner surface. These results indicate a highly asymmetric localization of inner membrane components.     

Calcium-Binding Properties of the Mitochondrial Channel-Forming Hydrophobic Component

A hydrophobic, low-molecular weight component extracted from mitochondria forms aCa²⁺-activated ion channel in black-lipid membranes (Mironova et al., 1997). At pH 8.3–8.5, thecomponent has a high-affinity binding site for Ca²⁺ with a K_d of 8 × 10^–6 M, while at pH7.5 this K_d was decreased to 9 × 10^–5 M. B_max for the Ca²⁺-binding site did not changesignificantly with pH. In the range studied, 0.2 ± 0.06 mmol Ca²⁺/g component were boundor one calcium ion to eight molecules of the component. The Ca²⁺ binding was stronglydecreased by 50–100 mM Na⁺, but not by K⁺. Treatment of mitochondria withCaCl₂ priorto ethanolic extraction resulted in a high level of Ca²⁺-binding capacity of the partially purifiedcomponent. Cyclosporin A, a specific inhibitor of the mitochondrial permeability transition,when added to the mitochondrial suspension, decreased the Ca²⁺-binding activity of thepurified extract severalfold. The calcium-binding capability of the partially purified componentcorrelates with its calcium-channel activity. This indicates that the channel-forming componentmight be involved in the permeability transition that stimulates its formation.     

郁金化学成分的研究

从郁金块根中分离得到10个化合物,经化学方法和光谱分析,分别鉴定为环二十二酸内酯(1),阿魏酸乙酯(2),6—methyl-7-(3-oxobutyl)-bicyclo[4.1.0]heptan-3-one(3),异莪术烯醇(4),莪术烯醇(5),阿魏酸(6),姜黄素(7),去甲氧基姜黄素(8),二去甲氧基姜黄素(9)和胡罗卜苷(10),其中1为新化合物,3为新的天然产物,2,3和6为首次从该属植物中分得。     

Amino Acids as Nitrogen Sources for the Growth of Euglena gracilis and Astasia longa

SYNOPSIS. Euglena gracilis (bacillaris variety, strain SM-L1, streptomycin-bleached) used the following amino adds (10⁻³ M) as sole nitrogen source for growth on a defined medium: glycine, alanine, valine, leucine, isoleucine, serine, threonine, and glutamic acid. Aspartic acid was used at 10⁻² M. Glutamine and asparagine were used at 10⁻³ M and were better N sources than their parent dicarboxylic amino acids. Not used as sole N source for growth were phenylalanine, tyrosine, tryptophan, cysteine, cystine, methionine, proline, hydroxyproline, histidine, arginine, lysine, and taurine. Astasia longa (Jahn strain) was more restricted than Euglena and used only asparagine and glutamine as N sources for growth.     

Triosephosphate isomerase genes in two trophic modes of euglenoids (euglenophyceae) and their phylogenetic analysis

Two different length cDNAs encoding triosephosphate isomerase (TIM) were identified in the two trophic modes of euglenoids, the phototrophic Euglena gracilis and Euglena intermedia and the saprotrophic Astasia longa. Sequence analyses and presequence prediction indicated that the shorter cDNA encodes a cytosolic TIM and the longer cDNA encodes a plastid TIM (pTIM). The typical presequence of the putative A. longa pTIM and the high sequence similarity between A. longa pTIM and E. gracilis pTIM imply that A. longa pTIM is targeted to plastids. Therefore, although the plastids of A. longa have lost the ability of photosynthesis, they might retain other TIM-related function(s), such as glycolysis and the synthesis of isopentenyl diphosphate or fatty acids. Including the TIM sequences obtained by us from chlorophytes and rhodophytes, our phylogenetic analyses indicated that euglenoid TIMs group neither with TIMs of kinetoplastids, which share the nearest common ancestor with euglenoids, nor are closely related to TIMs of chlorophytes, which are considered to be the donors of euglenoid plastids through secondary endosymbiosis. Instead, they group with TIMs of rhodophytes. In addition, our amino acid sequence alignment and structure modeling showed that TIMs of euglenoids and rhodophytes share a unique 2-aa insertion within their loop-4 areas. Therefore, either tim convergent evolution or lateral gene transfer (more probably) might have occurred between euglenoids and rhodophytes after the divergence of euglenoids with kinetoplastids.     

Channels in Mitochondrial Membranes: Knowns,Unknowns, and Prospects for the Future

Abstract

Rapid diffusion of hydrophilic molecules across the outer membrane of mitochondria has been related to the presence of a protein of 29 to 37 kDa, called voltage-dependent anion channel (VDAC), able to generate large aqueous pores when integrated in planar lipid bilayers. Functional properties of VDAC from different origins appear highly conserved in artificial membranes: at low transmembrane potentials, the channel is in a highly conducting state, but a raise of the potential (both positive and negative) reduces drastically the current and changes the ionic selectivity from slightly anionic to cationic. It has thus been suggested that VDAC is not a mere molecular sieve but that it may control mitochondrial physiology by restricting the access of metabolites of different valence in response to voltage and/or by interacting with a soluble protein of the intermembrane space. The latest application of the patch clamp and tip-dip techniques, however, has indicated both a different electric behavior of the outer membrane and that other proteins may play a role in the permeation of molecules. Biochemical studies, use of site-directed mutants, and electron microscopy of two-dimensional crystal arrays of VDAC have contributed to propose a monomelic β barrel as the structural model of the channel. An important insight into the physiology of the inner membrane of mammalian mitochondria has come from the direct observation of the membrane with the patch clamp. A slightly anionic., voltage-dependent conductance of 107 pS and one of 9.7 pS, K⁺-selective and ATP-sensitive, are the best characterized at the single channel level. Under certain conditions, however, the inner membrane can also show unselective nS peak transitions, possibly arising from a cooperative assembly of multiple substates.     

索氏法提取姜黄挥发油及其成分的研究

本文以广西那坡县种植的姜黄为原料,分别以沸点为30-60℃,60-90℃的石油醚以及石油醚与乙醚的混合物作为溶剂,采用索氏提取法提取挥发油,并采用GC-MS分析法研究了这几种姜黄挥发油的主要成分,比较了不同的加工办法对挥发油的加工得率、主要成分、含量的影响。研究表明：用索氏提取法提取的广西姜黄挥发油其得率在7％以上,主要成分为：α-姜黄烯、（-）-姜烯、β-倍半水芹烯、芳姜黄酮、β-姜黄酮、α-姜黄酮、β-没药烯。     

Localization of Mannose, TV-Acetylglucosamine and Galactose in the Golgi Apparatus, Plasma Membranes and Cell Walls of Scenedesmus acuminatus

The localization of lectin binding sites in the Golgi apparatus,plasma membranes and cell walls of Scenedesmus acuminatus wasinvestigated by cytochemical electron microscopy. The lectinsused were concanavalin A (Con A), peanut agglutinin (PNA) andwheat germ agglutinin (WGA), all labeled with gold. Con A-goldparticles were deposited not on the Golgi apparatus, but onthe outer cell-wall layer. PNA-gold and WGA-gold particles weredeposited on distal Golgi cisternae and vesicles derived fromthe Golgi apparatus. Entire cell-wall layers were evenly labeledby PNA-gold. The plasma membrane and cytoplasmic regions closeto the plasma membrane were labeled with WGA-gold. The processingof oligosaccharide in the Golgi apparatus, plasma membranesand cell walls of Scenedesmus acuminatus is discussed in referenceto that reported for animal cells. (Received March 5, 1987; Accepted July 18, 1987)     

The efficacy and safety of Curcuma longa extract and curcumin supplements on osteoarthritis: a systematic review and meta-analysis

Objective: To assess the efficacy and safety of Curcuma longa extract and curcumin supplements on osteoarthritis (OA).Methods: The databases such as Pubmed and Cochrane Library were searched to collect the article about Curcuma longa extract and curcumin in the treatment of OA. Then, randomized controlled trials (RCTs) were selected and their data were extracted. Finally, the RevMan5.3 was utilized for risk of bias assessment and meta-analysis, the STATA15.0 were utilized for publication bias assessment, and GRADE tool were used for the evidence quality assessment of primary outcomes.Results: A total of 15 RCTs involving 1621 participants were included. (1) Compared with placebo, Curcuma longa extract and curcumin (C.) can decrease the visual analog scale (VAS) and The Western Ontario and McMaster Universities (WOMAC) score-pain, the WOMAC score-function and the WOMAC score-stiffness. In terms of adverse events, Curcuma longa extract and curcumin are comparable with those of placebo. (2) Compared with non-steroidal anti-inflammatory drugs (NSAIDs), Curcuma longa extract and curcumin have similar effects on joint pain, function and stiffness. The incidence of adverse events in Curcuma longa extract and curcumin was lower. (3) Compared with the NSAIDs group, C.+NSAIDs can also decrease the VAS and WOMAC score-pain, the WOMAC score-function and the WOMAC score-stiffness. In terms of adverse events, the addition of Curcuma longa extract and curcumin to NSAIDs did not increase adverse events.Conclusion: Curcuma longa extract and curcumin may be a safer and effective supplement for OA patients. It is recommended to use Curcuma longa extract and curcumin supplement for OA patients for more than 12 weeks.