多变鱼腥藻藻胆体的分离和荧光鉴定其完整性与解离程度

完整藻胆体的室温荧光峰位于678nm附近,而不完整藻胆体其峰位于673nm以下。在液氮温度下,完整藻胆体的F686与F666相对荧光强度比值超过10,F686与F655之比值超过20。不完整藻胆体的F686与F666和F686与F655之比值远低于完整藻胆体。可用室温荧光峰的波长位置和液氮温度下F686与F655和F666的相对荧光强度比值来判断藻胆体的完整性和解离程度。而液氮温度下F686与F655,F666之比值是更灵敏的指标。       

EFFECT OF LIGHT WAVELENGTH ON SUPPRESSION AND PHASE DELAY OF THE MELATONIN RHYTHM

Different wavelengths of light were compared for melatonin suppression and phase shifting of the salivary melatonin rhythm. The wavelengths compared were 660 nm (red), 595 nm (amber), 525 nm (green), 497 nm (blue/green), and 470 nm (blue). They were administered with light-emitting diodes equated for irradiance of 130 μW/cm². Fifteen volunteers participated in all five wavelength conditions and a no light control condition, with each condition conducted over two consecutive evenings. Half-hourly saliva samples were collected from 19:00 to 02:00 on night 1 and until 01:00 on night 2. Light was administered for the experimental conditions on the first night only from midnight to 02:00. Percentage melatonin suppression on night 1 and dim light melatonin onset (DLMO) for each night were calculated. The shorter wavelengths of 470, 497, and 525 nm showed the greatest melatonin suppression, 65% to 81%. The shorter wavelengths also showed the greatest DLMO delay on night 2, ranging from 27 to 36 min. The results were consistent with the involvement of a scotopic mechanism in the regulation of circadian phase. (Chronobiology International, 18(5), 801-808, 2001)     

赤霉素及竹红菌甲素荧光量子产率的常量化区域

通过对赤毒素、竹红菌甲素及苯酚量子产率的测定与比较发现,这三种荧光化合物都具有一个相对于激发波长的量子产率的稳定区域。尽管它们具有多个激发峰,但不同激发峰所激发的荧光量子产率差别较小。竹红菌甲素在室温放置一个月,690nm荧光光谱有明显的改变。以上结果提示在测定未知荧光化合物的量子产率时,被测溶液的散射较强,同时荧光物的激发与发射波长彼此相接近。量子产率较弱时,可以在最大激发峰的蓝移方向上选择激发波长来避免散射光的干扰,提高量子产率测定的准确度。竹红菌甲素在690nm的荧光肩峰,可能是分子空间结构上容易发     

ATP－乙醛磺酸衍生物的荧光性质

２－氨基乙磺酸类似物乙醛磺酸（ＳＡＤ）具有荧光（ＥＸ：３１４ｎｍ;ＥＭ：４００ｎｍ）。ＳＡＤ与ＡＴＰ反应过程中醛基减少的时间动力学表明,ＡＴＰ在３７℃经过４小时可能完全与ＳＡＤ反应。ＳＡＤ与ＡＴＰ反应的结果可使ＡＴＰ的荧光增强约一倍。以上结果表明：ＳＡＤ可以在上述温和条件下与ＡＴＰ进行反应,因此,ＳＡＤ可能成为一种ＤＮＡ和ＲＮＡ的修饰或调节分子。     

ATP－乙醛磺酸衍生物的荧光性质

２－氨基乙磺酸类似物乙醛磺酸（ＳＡＤ）具有荧光（ＥＸ：３１４ｎｍ;ＥＭ：４００ｎｍ）。ＳＡＤ与ＡＴＰ反应过程中醛基减少的时间动力学表明,ＡＴＰ在３７℃经过４小时可能完全与ＳＡＤ反应。ＳＡＤ与ＡＴＰ反应的结果可使ＡＴＰ的荧光增强约一倍。以上结果表明：ＳＡＤ可以在上述温和条件下与ＡＴＰ进行反应,因此,ＳＡＤ可能成为一种ＤＮＡ和ＲＮＡ的修饰或调节分子。     

固定对组织光学性质的影响

利用带有积分球的SHIMADZU UV—240分光光度计,测量了组织在固定前和后的反射率和透射率,分析了福尔马林固定对组织光学性质的影响。     

OCCURRENCE OF TRI-LAMELLAR BODIES IN ISOLATES OF NOSTOC (CYANOPHYCEAE)1

Tri-lamellar bodies were observed in eight of 29 isolates of Nostoc examined. They appeared identical to the previously described bodies in various species of Anabaena. The bodies consist of three discoid lamellae each ca. 0.3 μm diam and 8 nm thick. The outer lamella (closest to the plasma membrane) is separated from the middle lamella by a 12 nm space whereas the middle and inner lamellae are ca. 8 nm apart. Osmiophilic striations 3 nm wide were generally observed running between the lamellae. Osmiophilic β granules were usually associated with the inner lamella. The bodies were most always located close to the plasma membrane along the longitudinal wall near the junction of the cross and longitudinal walls. In three isolates the bodies located near the cross walls were associated with gas vesicles and possessed a slightly different morphology. These tri-lamellar bodies consisted of three discoid lamellae, each ca. 2 nm thick, ca. 25 nm apart with electron dense material between the inner and middle lamellae. Pores 20 nm diam and ca. 60 nm apart were observed in layer 2 of the cell wall adjacent to the tri-lamellar bodies. These wall pores were also observed in isolates lacking tri-lamellar bodies.     

组织蛋白酶D和nm23基因蛋白在乳腺癌中的表达及与淋巴结转移的关系

采用免疫组织化学 ABC法检测了 43例乳腺癌中的组织蛋白酶 D和 nm 2 3基因蛋白的表达。结果显示组织蛋白酶D在乳腺癌组织中表达阳性率为 76 .7% (33/43)。 43例乳腺癌中 2 5例伴有淋巴结转移 ,18例无淋巴结转移 ,其组织蛋白酶D表达阳性率分别为 92 % (2 3/2 5 )及 5 5 .6 % (10 /18) ,两者之间具有显著性差异 (P<0 .0 1)。 nm 2 3基因蛋白在 43例乳腺癌中阳性率为 72 .1% (31/43)。在有淋巴结转移和无淋巴结转移的乳腺癌中 nm2 3基因蛋白阳性率分别为 6 0 % (15 /2 5 )及80 .9% (16 /18) ,nm2 3基因蛋白的表达与淋巴结转移呈显著负相关 (P<0 .0 5 )。结果提示对乳腺癌根治术后无淋巴结转移 ,但组织蛋白酶 D表达阳性 ,nm2 3基因蛋白表达阴性的患者 ,可能具有潜在的复发和转移倾向 ,应多加关注 ,并密切随访。     

蓝细菌Synechocystis sp.PCC6803中叶绿素合成调控类囊体膜重建的研究

利用ＤＮＡ体外重组技术构建了蓝细菌Ｓｙｎｅｃｈｏｃｙｓｔｉｓｓｐ．ＰＣＣ６８０３突变种ＯＲＦ４６９,它的染色体ＤＮＡ缺失ＯＲＦ４６９片段,该突变种在加入５ｍｍｏｌ／Ｌ葡萄糖的ＢＧ－１１培养基中经遮光培养２周后叶绿素全部消失,细胞甲醇提取液光谱中６６５ｎｍ处叶绿互峰消失,６２９ｎｍ处出现原叶绿素酸酯峰,完整细胞光谱仅存在６２０ｎｍ的藻胆蛋白肩峰,细胞的类囊体膜消失,但藻胆体颗粒并未减少;细胞培养物重     

MEASURING PHOTOSYNTHETIC ACTION SPECTRA OF NATURAL PHYTOPLANKTON POPULATIONS1

The photosynthetic response, defined as the initial slope of the photosynthesis-irradiance curve, was determined spectrally (every 25 nm from 400 to 675 nm; 25 nm half-maximum bandpass) for natural phytoplankton populations from High Arctic, Grand Banks and Sargasso Sea waters, as well as for populations living in the lower margin of sea ice off Newfoundland, All spectra were similar in shape with a maximum at 425–450 nm, a broad shoulder to 550 nm, a valley from 600 to 650 nm and a rise at 675 nm. The error resulting from the use of spectrally averaged initial slope to predict photosynthesis under different optical and fluid dynamical conditions at sea is discussed.     

家蚕核型多角体病毒及核衣壳的纯化和其结构蛋白的凝胶电泳分析

 用差速离心和蔗糖密度梯度离心提纯了家蚕核型多角体病毒及其核衣壳,并用SDS聚丙烯酰胺凝胶(均一胶和梯度胶)电泳分析了它们的结构蛋白。测量使用游标卡尺,计算使用微型计算机。凝胶用很染色方法染色。 结果表明,家蚕核型多角体病毒长381.2±17.81纳米,直径88.86±9.605纳米;核衣壳长328.9±5.917纳米,直径41.36±1.167纳米。两种凝胶电泳所得数据显示病毒粒子至少含有20组分子量不同的结构多肽,含量较多的是P31、P40、P28和P20。P45和一些小分子多肽看来主要存于囊膜上。P31的分子量与多角体蛋白相同,我们的实验表明它可能是病毒粒子和核衣壳的结构组分。     

多变鱼腥藻(Anabaena variabilis)藻胆体——类囊体膜光能传递的研究

多变鱼腥藻(Anabaena variabilis)藻胆体一类囊体膜的吸收峰位于678,624,490,438和418nm.当用580nm波长光激发藻胆体一类囊体膜中藻胆蛋白时,室温荧光峰位于662nm,在680nm附近有一肩;液氮温度荧光峰位于655,666,695和730nm.这说明藻胆蛋白捕获的光能能有效地传给叶绿素a.当用436nm波长光激发藻胆体一类囊性膜中叶绿素a时,室温荧光峰(?)于683nm;液氮温室荧光峰在730nm,另一小峰在695nm.表明叶绿素a捕获的光能不能传递给藻胆蛋白.藻胆体一类囊体膜放氧速率为245μmoleO_2/小时,毫克叶绿素,电境照片显示在类囊体膜上有大量藻胆体.用0.3M蔗糖,O.05M磷酸缓冲溶液洗藻胆体一类囊体膜,能使藻胆体与类囊体膜分开.对藻胆体与类囊体之间的光能传递进行了讨论.     

FREEZE FRACTURE STUDY OF THYLAKOIDS OF FUCUS SERRATUS1

Freeze-fractured thylakoids of Fucus serratus L. exhibit three types of faces with a particle density analogous to that of EFs, EFu and PF faces of green plants. However the particle size distribution is unimodal in the three types with a mean of about 8 nm. No obvious distinction between PFs and PFu faces could be detected. The absence on EFs faces of the distinct class of large particles (>13 nm) existing in green plant thylakoids implies a unique organization of pigment proteins, especially of the light-harvesting complexes.     

氦氖激光对鱼类生长的影响

本试验采用氦氖激光(632.8nm)以不同的功率和不同功率密度,或者不同的辐照方式,辐照孔雀幼鱼(Poecilia reticulata)、尼罗罗非鱼(Oreochromis niloticus)和淡水白鲳(Ephippus orbis)。实验结果表明,He-Ne激光辐照对三种幼鱼的生长均有促进的作用,并且不同的功率和功率密度的影响是不同的,适当的激光参量会产生较佳的影响效果。     

蛋白质二硫键异构酶的纯化和活力测定

 从500g新鲜牛肝制得蛋白质二硫键异构酶(PDI,EC 5.3.4.1)98mg。该酶制剂在SDS-聚丙烯酰胺凝胶电泳中表现为亚基分子量62,000的均一条带。在260nm追踪,因二硫键错接而失活的牛胰核糖核酸酶A,经PDI作用使其二硫键重排恢复活力,从而催化酵母RNA的水解来测定PDI活力。这种单波长法比文献中介绍的追踪A_(260)—A_(280)的双波长法更为灵敏方便。酶的克分子消光系数ε_M=1.03×10~5(pH7.5),其比活性为1400单位/克蛋白质。     

THE FINE STRUCTURE OF THE SHELL MUSCLE OF PATELLID PROSOBRANCH LIMPETS

The structure of the shell muscle of eleven species of patellidlimpet is described from light and transmission electron microscopestudies. Although the muscle has many structural characteristicstypical of molluscan smooth muscle, it also has a number ofunusual features. At the electron microscope level two myofibretypes are distinguishable. Type I cells, present in all species,contain conventional contractile apparatus in the form of thickand thin filaments. Thick filaments contain paramyosin and varyin diameter between 20—180 nm. An axial striation witha repeat of 14.2 nm is calculated from optically diffractedmicrographs of isolated thick filaments. Transverse sectionsof thick filaments reveal bands from which the transverse repeatof the paramyosin crystal lattice is calculated. Type II myofibres,which are present in five species, contain a novel arrangementof thin filaments with electron-dense regions at intervals of80–150 nm. The striated thin filaments are similar inappearance to the microfilament bundles and stress-fibres ofnon-muscle cells. They also have similarities to the leptomericorganelles of some vertebrate muscle tissues. Associated withthe muscle is an unusually large amount of collagen which hasa periodicity of 62 nm calculated from optical diffraction patternsof isolated collagen fibrils. (Received 3 July 1989; accepted 12 October 1989)     

THE DETERMINATION OF THE FAR-RED EFFECT IN MARINE PHYTOPLANKTON1,2

A far-red effect exists in 4 marine phytoplankton species: the diatom Ditylum brightwelli, the coccolithophorid Coccolithus huxleyi, the green flagellate Dunaliella tertiolecta, and the dinoflagellate Pyrocystis lunula. The effect is reversible and is manifested through a change in cell division rate. Cultures of algae which received 30-min far-red (FR) light (750 nm) prior to the dark period were compared to controls which received, no FR. Reversal of the FR effect was studied by exposing experimental cultures to 30 min FR followed by 5-min red (R) light (650 nm) prior to the dark period. Controls received only FR. Cultures were exposed to light at 6 different enumerated wavelengths between 460 and 750 nm. A decrease in division rate runs evident only with light at 750 nm. These results give evidence for the presence of the phytochrome system in these phytoplankton species.     

STRUCTURE AND PHYCOBILIPROTEIN COMPOSITION OF PHYCOBILISOMES FROM GRIFFITHSIA PACIFICA (RHODOPHYCEAE)1

Phycobilisomes in Griffithsia pacifica are closely spaced on the thylakoid membrane. By negative staining, attached and isolated phycobilisomes have been shown to have a block shaped appearance. They are 63 nm long, 38 nm high, and 38 nm wide, making them the largest thus far reported. Isolated phycobilisomes, shown to be functionally intact by their 675 nm fluorescence emission (excitation 545 nm) were stable for more than a day. Phycobiliproteins from dissociated phycobilisomes, separated on sucrose gradients and by polyacrylamide electrophoresis, yielded large (R-) and small (r-) molecular weight species of phycoerythrin (ca. 4:1 respectively) constituting 89% of the phycobiliprotein content, with R-phycocyanin 8%, and allophycocyanin 3% accounting for the rest. Phycobilisomes of Griffithsia pacifica and Porphyridium purpureum (Bory) Drew and Ross (P. cruentum) are structurally very similar with phycoerythrin being on the outside and surrounding a core of R-phycocyanin and allophycocyanin.     

癌症病人血液的荧光光谱研究

研究了癌症病人全血、血浆和血红蛋白的激发波长—发射波长—荧光光强三维光谱,观察到特征谱带625nm的荧光本原物质存在于血红蛋白部分,比较了十五种癌症(28例),十例非癌症病人和健康人血液在625nm带的荧光强度.     

用光谱技术鉴定植物色素突变体

1983年我国报道了从γ-射线处理的“矮杆齐”大麦中得到了一株黄绿色的突变体1832C[1]。本文用光谱技术对该突变体的光合色素成分进行了鉴定。1　材料和方法　　材料为六棱裸大麦“矮杆齐”和由该品种大麦诱变形成的黄绿色突变体1832C(Mb1832C),以及作为对照的缺失Chlb的突变体大麦Chlorina-f2[2]都于3月初播种于实验田中。　　每个样品取30g新鲜的叶片,先用自来水后用蒸馏水冲洗干净。把洗净的叶片摊放在干净的纱布上吸干表面水分,剪碎,加入100mL预冷的含有0.4mol/L山梨醇、0.1mol/LTris-HCl(pH7.6)的缓冲液,用组织捣碎机先慢速捣碎1…