畲族Ge,PGM1,AcP1,6—PGD,ADA和AK1的遗传多态性

对畲族血浆组特异性成分、红细胞磷酸葡萄糖变位酶１（ＰＧＭ１）、酶性磷酸酶（ＡｃＰ１）、６－磷酸葡萄糖酸氢酶（６－ＰＧＤ）、腺苷脱氨酶（ＡＤＡ０、腺苷酸激酶（ＡＫ１）的遗传多态性进行了研究。Ｇｃ与ＰＧＭ１是用薄层聚丙烯酰胺凝胶等电聚集分析的,ＡｃＰ１、６－ＰＧＤ、ＡＤＡ及ＡＤ１是用淀粉凝胶电泳分析的。各基因座的基因频率分别为Ｇｃ１Ｆ０．４７２２、Ｇｅ１Ｓ０．２４２１、Ｇｃ２０．２７３８;ＰＧＭ１１Ａ     

汉族9个人群AcP_1、EsD及6-PGD的遗传多态性

用淀粉凝胶电泳法对我国汉族９个人群的红细胞酸性磷酸酶（ＡｃＰ１）、酯酶Ｄ（ＥｓＤ）、及６－磷酸葡萄糖酸脱氢酶（６－ＰＧＤ）的遗传多态性进行了研究。研究结果表明：兰州、呼和浩特、哈尔滨、西安、郑州、成都、贵阳、漳州、梅州等９市汉族人群的ＡｃＰＢ１基因频率依次为０．７９２９、０．８１６７、０．７９３８、０．８１３１、０．８０８８、０．８００５、０．７８９６、０．７７９４和０．７６７５;ＥｓＤ１基因频率依次为０．６４７３、０．６１４８、０．６４４３、０．６４３９、０．６４７５、０．６３０５、０．６２８７、０．５９０７和０．５８２５;６－ＰＧＯＡ基因频率依次为０．８８８１、０．９１４３、０．９３３０、０．９３１８、０．８７５６、０．９２１２、０．９１８８、０．９４６１和０．９３７５。ＥｓＤ１基因频率在中国南、北方人群间有差异,北方人群的ＥｓＤ１频率高于南方人群,随着北纬纬度由高向低,汉族人群ＥｓＤ１频率也随着从北向南降低。在中国汉族人群中,ＥｓＤ基因及６－ＰＧＤ基因分化比较显著,而ＡｃＰ基因分化则不显著     

用蛋白质工程方法改变葡萄糖异构酶最适pH和最适温度

用寡核苷酸诱导的定点突变方法构建了葡萄糖异构酶基因的突变体（Ｎ１８４Ｄ和Ａ１９８Ｃ）。含突变体的重组质粒ｐＴＫＤ－ＧＩ１（Ｎ１８４Ｄ）和ｐＴＫＤ－ＧＩ２（Ａ１９８ｃ）在Ｅ．ｃｏｌｉＫ３８菌株中表达,用ＤＥＡＥ－Ｓｅｐｈａｒｏｓｅ ＦＦ和Ｓｅｐｈａｃｒｙｌ Ｓ－３００ＨＲ柱层析分离纯化突变酶。与野生型葡萄糖异构酶比较实验表明：（１）突变酶Ｎ１８４Ｄ的最适ｐＨ值下降了１个单位;等电点下降了０．６个单位     

酵母K.fragilis甘油醛—3—磷酸脱氢酶基因的克隆

根据已克隆的马克斯克鲁维酵母（Ｋ．ｍａｒｘｉａｕｓ）,乳酸克鲁维酵母（Ｋ．ｌａｃｔｉｓ）与酿酒酵母（Ｓ．ｃｅｒｅｖｉｓｅｉａｅ）甘油醛－３－磷酸脱氢酶（ＧＡＰ）基因的核苷酸序列同源性分析设计ＧＡＰ探针,以该探针与脆壁克鲁维酵母（Ｋ．ｆｒａｇｉｌｉｓ）ＣＢＳ３９７基因文库进行原位杂交,得到一阳性克隆ｐＧ１并通过Ｓｏｕｔｈｅｒｎ印迹杂交实验得以证实。该克隆所携带的ＧＡＰ１基因的部分序列也已被测定。利用     

四川南江两种水青冈种群遗传多样性初步研究

利用凝胶电泳法研究米心水青冈（Ｆａｇｕｓｅｎｇｌｅｒｉａｎａ）和巴山水青冈（Ｆ．ｐａｓｈａｎｉｃａ）２个种４个种群的遗传多样性。所测定的酶系统包括：过氧化物酶（ＰＸ１和ＰＸ２）,磷酸葡萄糖脱氢酶（ＰＧＤ）,酸性磷酸化酶（ＡＣＰ）,超氧物歧化酶（ＳＯＤ）,谷氨酸草酰乙酸转氨酶（ＧＯＴ１和ＧＯＴ２）,异柠檬酸脱氢酶（ＩＤＨ）,磷酸果糖异构酶（ＰＧＩ）,甲基萘醌还原酶（ＭＮＲ）,葡萄糖磷酸变位酶（ＰＧＭ１和ＰＧＭ２）和苹果酸脱氢酶（ＭＤＨ２）１０种酶系统。测定和分析了水青冈等位基因频率、遗传多样性、固定指数、Ｈａｒｄｙ－Ｗｅｉｎｂｅｒｇ平衡和遗传距离指标,为进一步研究水青冈属各种间的亲缘关系和进化提供了科学依据     

利用大肠杆菌表达系统进行葡萄糖－6－磷酸脱氢酶（G－6－PD）的生化鉴定

利用大肠杆菌表达系统进行葡萄糖－６－磷酸脱氢酶（Ｇ－６－ＰＤ）的生化鉴定卢义钦（湖南医科大学生化教研室，长沙４１００７８）关键词葡萄糖－６－磷酸脱氢酶（Ｇ－６－ＰＤ），大肠杆菌，表达葡萄糖－６－磷酸脱氢酶（Ｇ６ＰＤ）缺乏症在各民族人群中均有发现，据估...     

亮叶水青冈（Fagus lucida）种群遗传多样性初步研究

本文利用凝胶电泳法研究亮叶水青冈（Ｆａｇｕｓｌｕｃｉｄａ）种内遗传多样性。所测定的酶系统包括：过氧化物酶（ＰＸ１和ＰＸ２）、磷酸葡萄糖脱氢酶（ＰＧＤ）、谷氨酸草酰乙酸转氨酶（ＧＯＴ１和ＧＯＴ２）、异柠檬酸脱氢酶（ＩＤＨ）、甲基荼醌还原酶（ＭＮＲ）、葡萄糖磷酸变位酶（ＰＧＭ１和ＰＧＭ２）,苹果酸脱氨酶（ＭＤＨ２）、酸性磷酸酶（ＡＣＰ）和磷酸果糖升构酶（ＰＧＩ）９种酶系统１１个基因位点。测定和分析了亮叶水青冈２地理种群的等位基因频率,固定指致,基因多祥性和遗传距离,为进一步研究水青冈的遗传变异和种内种间关系提供了科学依据。     

P物质对GABAA和GABAB受体介导的DRG神经元膜反应的调制作用

实验在幼年大鼠ＤＲＧ标本上进行。应用细胞内记录观察了ＳＰ对ＧＡＢＡ反应的调制作用。结果证明：（１）单独滴加ＳＰ（５×１０（－６）－４×１０（－５）ｍｏｌ／Ｌ）或浴槽灌流ＳＰ（１０（－６）－５×１０（－６）ｍｏｌ／Ｌ）不引起膜电位的改变或仅有轻微的去极化,但却能使ＧＡＢＡ引起的去极化反应减小５０．８±２０．２％（±ＳＤ）（２０／３０）;（２）单独滴加ＳＰ可使多数受检细胞ＡＰＤ５０延长２８．７±９．１％（±ＳＤ）（１０／１８）;（３）在预加ＳＰ后,能使ｂａｃｌｏｆｅｎ所引起的ＡＰＤ５０缩短效应（２０．６±２．９％,±ＳＤ）完全消除（４／１２）或翻转成ＡＰＤ（５０）延长１９．３±８．９％（±ＳＤ）（８／１２）;（４）预加ＧＡＢＡＢ受体激动剂ｂａｃｌｏｆｅｎ（１０（－４）－１０（－３）ｍｏｌ／Ｌ）３０—９０ｓ后明显地抑制ｍｕｓｃｉｍｏｌ（１０－４－１０－３ｍｏｌ／Ｌ）引起的去极化反应,其抑制效应达５４．４±１８．８％（±ＳＤ）（１７／２０）。由于ＤＲＧ神经元的胞体通常可用来作为研究初级传入终末的模型,因而本文实验结果提示：介导伤害性刺激信息的Ｐ物质在背角的释放,可能作用于初级传入终末,从而产生对抗ＧＡＢＡ介导的突触     

甘油醛-3-磷酸脱氢酶与辅酶类似物ATP及底物磷酸结合特性的晶体学研究

气相扩散共晶生长法培养出Ｐ．ｖｅｒｓｉｃｏｌｏｒ龙虾肌ＡＴＰ－Ｄ－甘油醛－３－磷酸脱氢酶（ＡＴＰ－ＧＡＰＤＨ）的晶体。用同步辐射Ｘ光源－磷光储屏－Ｗｅｉｓｓｅｎｂｅｒｇ照相机系统收集了一套２．０分辨率的衍射数据。用同晶差值傅立叶法解析了其结构。精化后的结构模型最终Ｒ因子为０．１９７,与标准键长、键角的均方根偏差为０．０１６°和３．２０°。ＰｖＡＴＰ－ＧＡＰＤＨ结构总体上和Ｐｖａｐｏ－ＧＡＰＤＨ相似。ＡＴＰ分子的占有率较低,并表现出一定程度的无序性,提示ＡＴＰ与酶蛋白结合的稳定性较低,表明ＮＡＤ＋的尼克酰胺核苷部分与蛋白质分子的作用在辅酶与蛋白质的稳定结合中起关键作用。ＡＴＰ－ＧＡＰＤＨ中每个亚基只有一个磷酸结合位点（Ｐｉ）。认为无机磷酸结合位点Ｐｉ的形成不依赖于ＮＡＤ＋,而底物磷酸结合位点ＰＳ的形成则依赖于ＮＡＤ＋的存在。     

宫粉郁金的组织培养和快速繁殖

１植物名称宫粉郁金（Ｃｕｒｃｕｍａ　ｋｗａｎｇｓｉｅｎｓｉｓ）。２材料类别　块茎萌动芽。３培养条件　萌动芽生长培养基：（１）ＭＳ＋６－ＢＡ１ｍｇ·Ｌ－１（单位下同）＋ＮＡＡ０．２。不定芽增殖与愈伤组织诱导培养基：（２）ＭＳ＋６－ＢＡ１０＋ＫＴ５;（３）ＭＳ＋６．ＢＡ１０;（４）ＭＳ＋６－ＢＡ５＋ＫＴ２．５;（５）ＭＳ＋６－ＢＡ５;（６）ＭＳ＋６－ＢＡ２＋ＫＴ１。生根培养基：（７）ＭＳ＋ＮＡＡ０．５;（８）ＭＳ＋６－ＢＡ０．５＋ＮＡＡ０．５;（９）ＭＳ。以上培养基均加０．７％琼脂,３％蔗糖,ｐＨ５…     

GROWTH PATTERN,REPRODUCTION, AND SELF-THINNING IN SEAWEEDS1

In unispecific plant stands, the logarithm of mean individual weight (w) depends on the logarithm of density (d) by the -3/4 power law (a slope of -1.5 and an intercept ranging from 2.3 to 5.0). The analysis of the w and d relationships in whole cohorts of two seaweed species from the Strait of Gibraltar shows deviations from the canonical equation. The kelp Phyllariopsis purpurascens (C. Agardh) Henry et South (Phaeophyta) growing at a 30-m depth has the lowest intercept value (0.6) recorded for any plant species and a slope not significantly different from -1.5. The slope value is in accordance with those found in species whose growth is not stopped by reproduction. Irradiance under a single layer of blades was lower than the photosynthetic light compensation point, and this could be due to overdispersion of the shoots and, in consequence, to the low intercept value of the self-thinning equation. The w to d relationships in Asparagopsis armata Harvey (Rhodophyta) show two different components: no dependence between these two variables (slope not significantly different from 0) at densities < 500 shoots·m^?2, and a slope more negative (-2.1) than proposed by the -3/2 power law at densities > 500 shoots·m^?2. The pattern at high densities could be due to intraspecific competition for light, whereas the slope ～0 at low densities could be related to inhibition of growth by reproduction (cystocarp and carpospore production). Therefore, rather than being considered exceptional, we suggest that a gradient of variability could be expected in the dependence of w on d when specific growth patterns and reproduction are considered.     

人参皂甙Rb1,Rg1,Re和Rh1对体外培养细胞增殖的影响

本研究应用体外培养的人胚肺成纤维细胞(2BS)和人宫颈癌细胞(Hela)为实验模型。在培养液中分别加入人参根总皂甙(SRG)和人参皂甙Rb_1、Rg_1、Re、Rh_1孵育3～7d后,用MTT法和细胞计数法测定细胞的增殖。MTT测定结果表明,Rb_1、Rg_1、Re、Rh_1可以促进衰老细胞的增殖,但对未衰老的细胞增殖没有显著影响,对Hela细胞的增殖有抑制作用。细胞计数法测定结果表明,总皂甙和4种皂甙单体都可以降低Hela细胞的群体增殖率和克隆生长率,其中Re、Rh_1作用显著。同时,增加衰老细胞的群体增殖率和克隆生长率,其中Rb_1和Rg_1作用显著。     

DISTRIBUTION,MORPHOLOGY, AND PHYLOGENY OF KLEBSORMIDIUM (KLEBSORMIDIALES,CHAROPHYCEAE) IN URBAN ENVIRONMENTS IN EUROPE1

Klebsormidium is a cosmopolitan genus of green algae, widespread in terrestrial and freshwater habitats. The classification of Klebsormidium is entirely based on morphological characters, and very little is understood about its phylogeny at the species level. We investigated the diversity and phylogenetic relationships of Klebsormidium in urban habitats in Europe by a combination of approaches including examination of field‐collected material, culture experiments conducted in many different combinations of factors, and phylogenetic analyses of the rbcL gene. Klebsormidium in European cities mainly occurs at the base of old walls, where it may produce green belts up to several meters in extent. Specimens from different cities showed a great morphological uniformity, consisting of long filaments 6–9 μm in width, with thin‐walled cylindrical cells and smooth wall, devoid of false branches, H‐shaped pieces, and biseriate parts. Conversely, the rbcL phylogeny showed a higher genetic diversity than expected from morphology. The strains were separated in four different clades supported by high bootstrap values and posterior probabilities. In culture, these clades differed in several characters, such as production of a superficial hydro‐repellent layer, tendency to break into short fragments, and inducibility of zoosporulation. On the basis of the taxonomic information available in the literature, most strains could not be identified unambiguously at the species level. The rbcL phylogeny showed no correspondence with classification based on morphology and suggested that the identity of many species, in particular the type species K. flaccidum (kütz.) P.C. Silva, Mattox et W. H. Blackw., needs critical reassessment.     

NONPHOSPHORUS LIPIDS IN PERIPHYTON REFLECT AVAILABLE NUTRIENTS IN THE FLORIDA EVERGLADES,USA1

Algal and plant production of nonphosphorus lipids in place of phospholipids is a physiological response to low phosphorus (P) availability. This response has been shown in culture and in marine plankton studies, but examples from freshwater algae remain minimal. Herein, we analyzed the nutrient contents and lipid composition of periphyton communities across the Florida Everglades ecosystem. We hypothesized that in phosphate‐poor areas, periphyton in high‐ and low‐sulfate waters would vary the proportion of sulfolipids (SLs) and betaine lipids (BLs), respectively. In phosphate‐enriched areas, periphyton would produce more phospholipids (PLs). We observed that at low‐P sites, PLs were a minor lipid component. In cyanobacteria‐dominated periphyton where sulfate was abundant, BLs were only slightly more abundant than SLs. However, in the low‐P, low‐sulfate area, periphyton were comprised to a greater degree green algae and diatoms, and BLs represented the majority of the total lipids. Even in a P‐rich area, PLs were a small component of periphyton lipid profiles. Despite the phosphorus limitations of the Everglades, periphyton can develop tremendous biomass. Our results suggest a physiological response by periphyton to oligotrophic conditions whereby periphyton increase abundances of nonphosphorus lipids and have reduced proportions of PLs.     

COLCHICINE-INDUCED ALTERATIONS IN COLONY DEVELOPMENT IN EUDORINA ELEGANS (VOLVOCALES,CHLOROPHYTA)1

Colonies of Eudorina elegans Ehrenberg were treated with a 0.2% colchicine solution for periods of up to 48 h, and a number of alterations were observed in dividing colonies. Nuclear alterations were observed after 20 min of treatment, due to the inhibition of spindle microtubule polymerization. This inhibition resulted in increased ploidy levels, and permanent diploid colonies were obtained. The inhibition of cytoplasmic microtubule polymerization resulted in a number of structural alterations including: unequal cytokinesis of plakeal cells, the partial or complete inhibition of cytokinesis (30 min treatment), production of “stellate” cells (90 min treatment), and the subsequent formation of extra-cytoplasmic particles around the plakeal cells (3 h treatment). A possible cytoskeletal function of peripherally orient ed microtubules, and the role of the phycoplast microtubules is discussed. In addition, colchicine treatment caused an inhibition of inversion (60 min treatment), an increase in golgi-associated vesicles, and an excessive production of colonial envelope material (3 h treatment). The latter resulted in the formation of flattened Gonium-like colonies. The process of inversion is discussed in light of the above results. Chloroplast microtubules, however, were unaffected by colchicine treatment.     

PHAGOTROPHY IN THE FRESHWATER,PHOTOSYNTHETIC DINOFLAGELLATE AMPHIDINIUM CRYOPHILUM1

The cold-water, photosynthetic dinoflagellate Amphidinium cryophilum Wedemayer, Wilcox & Graham feeds phagotrophically on other dinoflagellate species. Food is ingested through a feeding tube, termed here the “phagopod,” which extends from the antapex. The peduncle of this organism plays no observable role in the feeding process. The phagopod is essentially a hollow cylinder composed electron-opaque material that is possibly deposited on a membrane. No Amphidinium cytoplasmic components, including microtubules or other cytoskeletal elements, were observed in the phagopod. Prefeeding cells aggregate, in small clumps near prey organisms with their phagopods extended. Eventually some cells commence feeding, first inserting the phagopod through the prey cell-covering and then slowly, over a period of 10 min or more, drawing cytoplasm through the phagopod and into a nascent food vacuole. Both light and electron microscopy suggest that one or more prey cell amphiesmal membranes remain intact during the feeding process. Upon completion of feeding, the Amphidinium cell swims off with a prominent food vacuole in the hypocone, leaving at least part of the phagopod attached to the prey cell. Phagotrophy in A. cryophilum seems to vary with light intensity. At low light intensities, cells feed phagotrophically and are nearly colorless, whereas at high light levels they feed much less frequently, if at all, and are brightly pigmented.     

MITOSIS,CYTOKINESIS, AND CELL ELONGATION IN THE DESMID,CLOSTERIUM LITTORALE1

Some details of interphase cell structure are given. At prophase the nuclear envelope breaks down and the nucleolus disperses; very small doubled chromosomes generally form a precisely aligned, metaphase plate with normal spindle microtubules present; 2 plates of chromatids separate during anaphase, the spindle becoming invaded, by (mucilage) vesicles. Telophase nuclei arc initially very hard to discern, until they increase in volume. Microtubules collect at each pole, becoming increasingly focused on one small region containing fine granular malarial, the microtubule center (MC). The septum, an annular ingrowth, begins forming at prophase and partitions the cell by telophase. At no stage were microtubules involved in this initial cross-wall formation. At telophase the spindle collapses and as the nuclei move back to the septum, increasing numbers of microtubules appear near this cross wall, all transversely aligned. An annular split deepens down the middle of the wall material in the septum, and the daughter cells begin to expand, stretching the new wall; the microtubules appearing near the septum now are transformed steadily into typical hooplike wall, microtubules, but strictly confined to the expanding wall (there are none near interphase cell walls). Meanwhile, the MC, has moved, to the side of the cell and begins migrating along one of the grooves in the chloroplast; a large number of parallel microtubules extends back to the nucleus, which becomes increasingly deformed as it begins to extend a long thin protrusion along these, microtubules. The MC keeps moving along the cell until it lodges in the cleavage developing in the chloroplast. Some microtubules extend still further up the cell, others appear in the chloroplast cleavage, but most en-sheathe the nucleus which by now is moving along the cell as a cylindrical structure tightly fitting in the chloroplast groove. The nuclear membrane is then drawn up into the deepening chloroplast constriction, and when the chloroplast is finally cut in 2, the nucleus lakes up its interphase position between the 2 halves. While all this is occurring, the whole cytoplasm is expanding into the new semicell being created by growth of the wall originally derived from the septum. Thus the interphase cell symmetry is reestablished after mitosis. These results are discussed in terms of more general phenomena of cell division and morphogenesis.     

PLASTID DIVISION IN MALLOMONAS (SYNUROPHYCEAE,HETEROKONTA)1

Laser scanning confocal microscopy and TEM were used to study the morphology of secondary plastids in algae of the genus Mallomonas (Synurophyceae). At interphase, Mallomonas splendens (G. S. West) Playfair, M. rasilis Dürrschm., M. striata Asmund, and M. adamas K. Harris et W. H. Bradley contained a single H‐shaped plastid consisting of two large lobes connected by a narrow isthmus. Labeling of DNA revealed a necklace‐like arrangement of plastid nucleoids at the periphery of the M. splendens plastid and a less‐patterned array in M. rasilis. The TEM of M. splendens and M. rasilis showed an electron‐dense belt surrounding the plastid isthmus in interphase cells; this putative plastid‐dividing ring (PD ring) was adpressed to the inner pair of the four plastid membranes, suggesting that it is homologous to the PD ring of green and red plastids. The PD ring did not contain actin (indicated by lack of staining with phalloidin) and displayed filaments or tubules of 5–10 nm in diameter that may be homologous to the tubules described in red algal PD rings. Confocal microscopy of chl autofluorescence from M. splendens showed that the plastid isthmus was severed as mitosis began, giving rise to two single‐lobed daughter plastids, which, as mitosis and cell division progressed, separated from one another and then each constricted to form the H‐shaped plastids of daughter cells. Similar plastid division cycles were observed in M. rasilis and M. adamas; however, the plastid isthmus of M. striata was retained throughout most of cell division and was eventually severed by the cell cleavage furrow.