甲壳动物血清中凝集素对微生物细胞的凝集性能

用12种甲壳动物血清凝集素提取液，对10种微生物细胞进行凝集试验，发现每种甲壳动物血清至少能凝集3种微生物细胞，酿酒酵母(Saccharomyces cerevisiae)细胞对凝集素反应最为敏感。7种甲壳动物血清凝集素对酿酒酵母细胞的凝集可被2种以上的糖所抑制，12种甲壳动物血清凝集素的温度和pH适应范围表现不一，但它们的凝集活性都被EDTA所抑制。     

经酶修饰和未经酶修饰的鹌鹑红细胞对甲壳动物血清凝集素凝集活性的差异研究

为寻找凝集素作为分子探针提供基础资料,用12种甲壳动物血清抽提液对天然的或经酶修饰的鹌鹑红细胞进行凝集试验。实验结果表明,经蜗牛酶修饰后的鹌鹑红细胞的凝集作用发生了变化,与未经酶处理的鹌鹑红细胞相比,凝集活性提高的有日本沼虾（Macrobrachium nipponense）等7种,凝集活性下降的有罗氏沼虾（Macrobrachium rosenbergi）等2种。凝集素对动物红细胞的凝集可看作是与这些细胞表面的多糖或糖蛋白——即受体的识别性鲒合,这表明鹌鹑红细胞表面具有12种凝集素的受体,且大多数受体都受到酶修饰的影响,从而在凝集活性上表现出差异。     

利用色谱和飞行时间质谱方法分离并鉴定七鳃鳗血清中凝集素

本研究利用阳离子交换和分子筛的方法成功分离鉴定出分子量为105kDa，以多聚体形式存在七鳃鳗凝集素。实验结果表明，首先运用阳离子交换色谱方法能够将七鳃鳗血清混合组分进行初步分离，结合凝集活性鉴定方法，鉴定凝集活性最强组分存在于第二峰中。其次；利用分子筛方法将具有凝集活性组分进一步分离，最终得到分子量为105kDa左右具有凝集活性组分。结合Native-PAGE和SDS-PAGE结果表明，凝集活性组分以三聚体形式存在。同时，飞行时间质谱方法鉴定结果为凝集素（gi:13094239）。最终，体外鉴定结果表明七鳃鳗凝集素对兔红细胞和山羊红细胞均具有较强的凝集活性。七鳃鳗凝集素的分离纯化对研究七鳃鳗先天免疫防御机制和可变淋巴受体介导的适应性免疫防御机制均具有重要意义。     

草鱼血清中一种新的凝集素免疫因子

于1998年5月－2000年3月，在浙江省杭州市采集草鱼，采用硫酸铵盐析和梯度聚丙烯酰胺凝胶电泳技术，从血清中分离出一种自然凝集素，对其理化和生物学性质进行研究。结果表明，该凝集素能够识别和凝集多种不同的红细胞、细菌和酵母，具有100000g离心不沉降，不被透析，耐热、耐酸、耐碱，抗DNase、RNase、SDS和乙醚，对胰蛋白酶、糖苷酶、糖氧化剂NaIO4和β－巯基乙醇敏感等特性，是一种分子量为67kD、等电点为6．2的糖蛋白分子。其活性能被半乳糖、乳糖、甘露糖和N－乙酰葡糖胺所抑制，其抗原特异性不同于草鱼凝集集抗IgM，表明两者是不同的物质。草鱼凝集素显著地促进巨噬细胞的吞噬、杀菌能力，说明是一种重要的免疫活性因子。     

外源凝集素──水产动物御敌的有力兵器

外源凝集素是非免疫起源的热敏蛋白质或糖蛋白，由于其多价构型及对持定细胞多糖具结合亲和力，它们选择凝集某些细胞（包括脊椎动物血球及一些病原微生物）和沉淀某些复杂碳水化合物；其凝集活动常被单糖所抑制，有的却需某些二糖、三糖或多糖。外源凝集素分离自广泛的低等和较高等的生物。一些地区水产养殖业受挫，因素较多，但对发病机理认识之缺乏和调动养殖对象本身防病积极性之不足，是其重要原因。外源凝集素可在诸如凝集外来细胞，调理作用等的防御活动中扮演识别因子，协助一些生理活性物发挥作用，参与吞噬、胞囊、凝固、止血及创伤修复等作用。在生物学、细胞学、生物化学、医学和食品科技上有广泛用途。迄今外源凝集素的许多性能并未全清，在自然界中的精细生理作用仍是个谜。本文论述外源凝集素的定义、性能及用途，以提请有关人士重视。     

脊条褶虾蛄血清及肌肉提取液凝集活性的比较

利用血凝试验及糖抑制试验测定脊条褶虾蛄的血清及肌肉提取液的凝血活性及糖抑制专一性，同时进行热稳定性、pH及Ca^2 影响试验。结果显示：其血清能凝集12种红细胞，且其凝集效价高于肌肉提取液（兔、蛇、鲫鱼除外）。血清对鹌鹑红细胞的凝集可被D－果糖、D－半乳糖和蔗糖所抑制，最小抑制浓度均为200mmol/dm^3，其凝集活性均依赖于Ca^2 ，在pH值为5.0-9.0范围内较稳定，经40℃保温10min后活性完全消失；肌肉提取液不被7种糖抑制，在pH值为4.0-10.0、温度为40－90℃范围内均具活性，说明有很强的耐热性，其凝集性不依赖于Ca^2 。以上结果表明：脊条褶虾蛄血清与肌肉提取液均含有凝集素，且凝集素的种类不同。     

绒螯蟹凝集素的红细胞凝集活性分析

利用血凝试验及糖抑制试验测定一种绒螯蟹的血清及肌肉提取液的凝血活性及糖抑制专一性,同时进行热稳定性、pH及Ca^2 影响试验。结果显示：血清只能凝集9种红细胞,肌肉提取液能凝集12种红细胞。血清对鹌鹁红细胞的凝集可被乳糖、D-甘露糖、D-果糖、D-半乳糖4种糖所抑制,最小抑制浓度均为200mmol／L,其凝集活性均依赖于Ca^2 ,在pH为6．0～7.0范围内较稳定,经50℃保温10min后活性完全消失。肌肉提取液只被D-甘露糖抑制,在pH为4．0～10．0、温度为4℃～90℃范围内均具活性,说明有很强的耐热性,其凝集活性不依赖于Ca。以上结果表明：血清与肌肉提取液均含有凝集素,且凝集素的种类不同。     

七种微藻蛋白质含量和氨基酸组成的比较

本文对来自４个门类的７种微藻的蛋白质含量和氨基酸组成进行了研究。结果表明,７种微藻中,钝顶螺旋藻（Ｓｐｉｒｕｌｉｎａ ｐｌａｔｅｎｓｉｓ）的蛋白质含量最高［４９． ８７５×１０~－２（ｍ／ｍ） ］,盐生杜氏藻（Ｄｕｎａｌｉｅｌｌａ ｓａｌｉｎａ）和 Ｎａｎｎｏｃｈｌｏｒｏｐｓｔｓ ｓｐ．的蛋白质含量次之,分别为［２１．０３６、２２．７４２×１０~－２（ｍ／ｍ）］; ４种硅藻中除优美旭氏藻（Ｓ．ｄｅｌｉｃａｔｕｌａ）的蛋白质含量较高外［１９．５１９×１０~－２（ｍ／ｍ）］,其它三种硅藻的含量则较低。不同微藻的氨基酸组成和比例基本相似,但也存在一定的种间差异。此外,微藻的必需氨基酸比例还与长牡蛎（Ｃｒａｓｓｏｓｔｒｅａ ｇｉｇａｓ）幼体进行了比较,探讨了它们的饵料价值。     

双壳贝类血清中凝集素凝集性能初步研究——对脊椎动物血细胞的凝集作用

在多种贝类血清中发现有可凝集脊椎动物血细胞的因子——凝集素。栉孔扇贝（Ｃｈｌａｍｙｓｆａｒｅｒｉ）血清中的凝集素可凝集鸡、鹌鹑、小鼠等多种动物血细胞,但对鳝鱼血细胞不发生作用。该凝集素具有较强的热稳定性,１００℃处理４５ｍｉｎ仍具活性;并具有广泛的ｐＨ范围,可在ｐＨ３～１１进行凝集作用。但其活性可被ＥＤＴＡ强烈抑制,Ｄ－甘露糖和Ｌ－鼠李糖对其活性有明显抑制作用,Ｄ－木糖和蕈糖也有轻微抑制作用。在栉孔扇贝血细胞的细胞膜上未发现有凝集鸡血细胞的活性物质。另外,用大肠杆菌和副溶血弧菌刺激栉孔扇贝后,血清的凝集作用不变。     

海藻凝集素研究进展

凝集素是一大类能够凝集生物细胞的蛋白或糖蛋白 ,广泛地存在于许多生物体内 ,在生物体的配子识别和生殖细胞融合中起着重要作用 ;许多生物凝集素表现为可以凝集人或动物的血细胞、蓝藻细胞、生殖细胞 (配子 )等多种细胞 ,同时某些凝集素具有抗病毒 ,促进淋巴细胞分裂 ,抗血小板凝集［２］和抗菌的作用。植物中较早发现的凝集素是陆生植物凝集素 ,其最早的应用是用来鉴别人的血型。１９６６年 ,Ｂｏｙｄ等人在一些热带海藻中发现了海藻凝集素的存在 ,此后Ｂｌｕｎ ｄｅｎ和Ｒｏｇｅｒｓ等对英国沿海的海藻检测了提取物的凝集活性 ,发现只有…     

海洋细菌在不同基质表面微生物粘膜中的组成

在青岛近岸海区两个不同地点 ,分别进行浸海挂片实验研究四种不同基质表面 (玻片、钢片以及涂有防污漆、防锈漆的玻片 )微生物粘膜中细菌组成。从不同基质表面微生物粘膜中共分离32 3株附着细菌 ,大多数为杆状或球杆状革兰氏阴性细菌 ,且大部分具有鞭毛。依据形态及生理生化特征将革兰氏阴性细菌鉴定到属 ,分别属于气单胞菌属 ( Aeromonas)、发光杆菌属 ( Photobacteri-um)、莫拉氏菌属 ( Moraxella)、假单胞菌属 ( Pseudomonas)、弧菌属 ( Vibrio)和产碱菌属 ( Alcali-genes)等 12个属 ,其中气单胞菌属是优势菌属。不同基质表面 ,微生物粘膜细菌组成不同     

FITC‐conjugated lectins as a tool for differentiating between toxic and non‐toxic marine dinoflagellates

FITC‐conjugated lectins proved to be effective probes for differentiating between morphologically similar dinoflagellate species isolated from New Zealand coastal waters. In particular the binding (fluorescence) of peanut (PNA) lectin differentiated G. mikimotoi from Gymnodinium sp. (Waimangu) and G. pulchellum and the non‐binding of Helix pomatia (HPA) and wheat germ (WGA) lectins discriminated between G. mikimotoi and the other Gymnodinium species tested. G. breve (Florida) was differentiated from the New Zealand isolates by binding with soy bean (SBA) lectin. Ulex europeus (UEA) distinguished the toxic species Alexandrium minutum from the morphologically similar, but non‐toxic, Cachonina hallii. Two strains of Prorocentrum lima (Spain and Rangaunu) were not differentiated by the lectins, but P. lima was differentiated from P. compressum.     

舟山港4艘商船压舱箱沉积物中甲藻孢囊种群结构的分析

为了解商船压舱箱沉积物在海洋水生生物入侵过程中扮演的潜在媒介作用,本文利用光学显微镜观察法,研究了停泊于我国舟山港4艘商船压舱箱沉积物中甲藻孢囊的种类组成、孢囊密度、香农-威纳指数(H′)和PSP原因种,并对甲藻孢囊种群结构进行了相关性分析。结果表明,鉴定出的甲藻孢囊隶属于5大类,共24种,4份样品中甲藻孢囊的种群结构各有差异,但均检测出能产生麻痹性贝毒(Paralytic Shellfish Poisons,PSP)的甲藻孢囊,如亚历山大藻Alexandriumspp.和链状裸甲藻Gymnodium catenatum。在4艘商船的压舱箱沉积物中均检测出有硅藻分布,其中在富成轮压舱箱沉积物中还检测出3种未知种孢囊。通过相关性分析可知,甲藻孢囊H′值与PSP甲藻孢囊密度占总甲藻孢囊密度的比率呈负相关。甲藻可以通过商船压舱箱沉积物为传播媒介,以孢囊形式来扩大其生物地理分布,提高甲藻物种多样性可有助于降低PSP甲藻的破坏风险。因此,有效处理船只压舱箱沉积物、积极保护当地海洋生物物种多样性,对于降低外来甲藻物种(特别是一些有毒有害种)的赤潮风险和保持当地海洋生态系统的平衡,具有十分重要的意义。     

Screening of Lectins in Crab and Shrimp from Fujian Coast of China

Twelve species of crustacean from Fujian coast were examined for lectins with different animal erythrocytes. Serum extracts fromall of 12 species showed agglutinating activity against at least two types of the erythrocytes used, which revealed the existence of lectins in these species. There were five species ( Penaeus japonicus, Lophosquilla costata, Charybdis feriatus, Portunus pelagicus, Scylla serrata ) whose serums could agglutinate all the erythrocytes tested. The lowest serum protein concentration required to produce erythrocytes agglutination varied remarkably, ranging from 0.7 μg/mL to 8 080 μg/mL. The strongest activity was shown in the agglutination of rabbit erythrocyte by serum of Penaeus vanaminas. Inhibition assays performed with seven mono- and bisaccharides showed that agglutination of quail erythrocytes by serums of three species (Portunus pelagicus, Scylla serrata and Sesarma sp. ) were not inhibited by any sugars, while others were inhibited by at least three types of sugars. The assay of temperature influence on agglutinating activity showed that only Penaeusjaponicus retained activity when the serum was heated to 90℃, and other serums lost their activity at 40 ℃, 50 ℃, 60 ℃, 70 ℃, 80 ℃ for 10 minutes, respectively.     

Complexation of Cu,Zn and Cd by metabolites excreted from marine diatoms

The excretion of photosynthetically fixed carbon from cultured marine diatoms and its influence on Cu, Zn and Cd complexation in seawater was studied for three species. For each species, an isolate from oligotrophic waters was compared with an estuarine isolate. Complexation of metal was determined with the use of differential pulse anodic stripping voltammetry. Excreted material from cells in log-phase growth complexed Cu > Zn > Cd, while material derived from senescent cells complexed only Zn. The filtrates of all cultures complexed these metals comparably with natural coastal seawater. There were no appreciable differences in complexing ability within or among species, suggesting that no excretion-complexation ‘strategy’ peculiar to each ecosystem exists among these species.     

2003-2004年浙江沿岸海域浮游植物的分布特征及其与环境因子的关系

2003年夏季和2004年夏、秋季,分别在浙江沿岸海域10m等深线(以下称内侧海域)和50 m等深线(禁渔线附近,以下称外侧海域)处共设置37个站位,对采集于大、小潮汛期间的浮游植物样品进行了种类组成、优势种、细胞丰度分布和群落结构特征的调查研究,并分析了其分布特征与环境因子的关系.结果表明,调查海域共鉴定出浮游植物3...     

Assessing DNA damage in cnidarians using the Comet assay

The assessment of DNA damage by the Comet assay has been described as a useful non-specific general biomarker of stress in many marine organisms. In field situations it has successfully been employed to distinguish between reference and polluted sites and in the laboratory it has been widely used as a mechanistic tool to determine pollutant effects and mechanisms of DNA damage. To date a wide range of marine vertebrates and invertebrates have been used, however, the usefulness of this assay as a biomarker in cnidarians has not yet been assessed. The aims of this study were to optimize the Comet assay for cnidarian cells and to assess its utility for detecting genotoxic damage in these cells. Cells were isolated from the North American pacific coast temperate sea anemone Anthopleura elegantissima using a non-enzymatic dissociation procedure and viability was determined to be in excess of 90%. Cells were incubated either with (1 h acute exposures) hydrogen peroxide (H(2)O(2)), ethylmethanesulphonate (EMS) or benzo(a)pyrene (B[a]P). In comparison to other marine species, anemone cells exhibited high control or background levels of DNA strand breaks. Despite this, however, we observed dose responses for each of the study chemicals with no reduction in cell viability. This study demonstrates that anemone cells respond to known DNA damaging agents, including B[a]P which requires metabolism to exert its genotoxic effect, and that the Comet assay may prove to be a useful biomarker of stress in cnidarian species.