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1.
秦松  王希华  童顺  曾呈奎 《海洋与湖沼》1995,26(S1):126-129
于1993年1月 - 1993年4月,为了制备遗传性纯一的基因工程受体,用酶法从海带雌配子体单性生殖系分离雌性单倍体原生质体。从皱纹盘鲍消化腺及消化器官提取出鲍酶,在25°C下、1%(WV)的鲍酶与2%(WV)的纤维素酶(Onozuka R-10)合用能有效解离单细胞和原生质体。海带雌性原生质体经2d培养再生了细胞壁。  相似文献   
2.
锶诱导的氧化胁迫对叉鞭金藻(Dicrateria inornata)的影响   总被引:3,自引:2,他引:3  
李梅  徐瑾  刘志礼  徐俊 《海洋与湖沼》2004,35(5):467-472
采用不同浓度的锶胁迫方法研究了叉鞭金藻生长、叶绿素、MDA含量及三种抗氧化酶SOD、CAT、GPX活性的变化。结果表明,在实验设计的各种Sr^2 浓度内叉鞭金藻均能生长,但Sr^2 浓度较高时生长受到不同程度的抑制,细胞数量比对照组分别减少15.9%和51.0%;叉鞭金藻中叶绿素含量随着Sr^2 浓度的升高而降低,呈负相关关系;叉鞭金藻中MDA含量在较低Sr^2 浓度下稍呈下降趋势,但与对照组相比并无显著差异,而在23.04mmol/L Sr^2 浓度时是对照的1.25倍;低Sr^2 浓度时,叉鞭金藻中蛋白质含量没有大的变化,当浓度超过5.76mmol/L时则引起蛋白质含量下降;叉鞭金藻中抗氧化酶SOD在低Sr^2 时分别降低12.5%、7.5%和9.5%,高Sr^2 时显著升高,为对照组的85.7%;CAT、GPX活性在低Sr^2 浓度时差别不大,但当浓度为23.04mmol/L时升高显著,比对照组分别增加了19.8%和74.4%。  相似文献   
3.
Copper (Cu) is an essential element for biological systems, however, when present in excess, is toxic. Metallothioneins can play an important role in Cu homeostasis and detoxification. Moreover, Cu can catalyse the production of toxic hydroxyl radicals that cause lipid peroxidation but defence systems in the cells can limit the oxidative damage. The present study was performed to investigate the effect of three Cu concentrations (0.5, 2.5 and 25 μg l−1) on the response of antioxidant enzyme activities (superoxide dismutase (SOD), catalase (CAT), selenium-dependent glutathion peroxidase and total glutathion peroxidase), total proteins, metallothioneins (MT), malondialdehyde (MDA) concentrations in the gills of the clam, Ruditapes decussatus. The activity of antioxidant enzymes and total proteins, MT and MDA concentrations were measured in the gills of the clams after 1, 3, 7, 14, 21 and 28 days of Cu exposure. Results indicate that Cu only induces an imbalance in the oxygen metabolism during the first week of Cu exposure due to a decrease in mitochondrial SOD and CAT, selenium-dependent and total glutathion peroxidase activities. Cu also causes lipid peroxidation, measured by the MDA formation, that was Cu dependent. In the gills of clams exposed to 25 μg Cu/l, the excess of Cu triggers the induction of MT synthesis after 3 days of exposure.  相似文献   
4.
产复合酶菌株Pseudomonas sp.NJ197产酶发酵条件的研究   总被引:2,自引:0,他引:2  
张金伟  曾润颖 《台湾海峡》2005,24(4):520-525
从南极普利兹湾深海900m的沉积物中筛选到一株同时产多种低温复合酶的菌 株NJ197,作者对其进行碳源、氮源、无机盐、起始pH值、培养时间、接种量等发酵条 件的优化实验.实验结果证明,在以0.5%可溶性淀粉为碳源,以0.5%豆饼粉为氮 源,无机盐:0.424%NH4H2PO4、0.075%K2HPO4、0.02%MgSO4、0.5%CaCO3,起始 pH值8.5,接种36h种龄的种子10%,20℃、250r/min的条件下在旋转摇床中培养 72h,产复合酶菌株产脂肪酶和淀粉酶活性最高.最佳的生理条件下复合酶中的碱性 脂肪酶和淀粉酶的产量分别提高到22.4U/cm3和30.9U/cm3,该产复合酶菌株可以 作为诱变育种、基因工程菌改造的出发菌株,在洗涤和制革工业中有良好的应用前 景.  相似文献   
5.
用组织学、组织化学和酶技术,对雌性莫桑比克罗非鱼在孵卵前后口腔粘膜的组织结构、抗菌酶的比活力变化进行初步研究。结果表明:在口腔粘膜的上皮中,杯状细胞是一个重要的结构,它随着雌鱼的生理状态的改变而变化。雄鱼、雌鱼和孵卵期的雌鱼口腔粘膜上皮中的杯状细胞数量上的差别显著。孵卵期的雌鱼口腔粘膜类似于哺乳动物的子宫粘膜也是受性激素影响的靶器官。该种鱼的口腔粘膜中存在着两种抗菌酶;蛋白质水解酶和壳多糖酶。孵卵前后,这两种酶的比活力分别提高1.4—2.03倍。说明孵卵时,口腔粘膜为使卵及仔鱼健康的发育,增强了抗菌能力。研究结果证明:抗菌力的增加与口腔粘膜中的杯状细胞的大量增生有着密切的关系。  相似文献   
6.
Abstract. A marine ecosystem in the crater of the Ushishir Volcano (Kraternaya Bight, Yankich Island, the Kuriles) showing gasothcrmal activity was studied for hydrographical, hydrochemical, and biological characteristics. Maximal changes in chemical and biological characteristics were observed in the surface water layer of 0–5 m. This layer had higher water temperature, was saturated with volcanogcnic carbon dioxide (up to 2000 10-6 torr), ovcrsaturatcd with oxygen (up to 200 %), and contained high concentrations of chlorophyll a. Hydrogen sulfide was found in the surface water layer and at a depth of 15 m in the area of maximal effect of volcanic effluents.
The planktonic community is characterized by high rates of production and destruction of organic matter only in the 0–5 m layer. Daily vertical migrations of the ciliatc Mesodinium rubrum were observed, which caused "red tides".
Bacterial, algobacterial, and diatom mats developed on the bottom of the bight in the zone of gasohydrothermal vents and in areas of volcanic water seeping. The rate of organic matter production in algobacterial mats reached 33.4g C-rrr2-d-l, chcmolithotrophy predominating. Bottom settlements had high population density and great animal biomass, which reached 10 kg m-2 in gasohydrothermal fields. They obtain sufficient energy from primary production of microphy-tobenthos, algobacterial, and bacterial mats. Bcnthic species dominant in the bight were not found off the Ushishir Islands.
Some species of macrobenthos inhabiting the Kraternaya Bight differ markedly in size and biomass from the same species found beyond the bight.  相似文献   
7.
本文研究了注射生物胺(多巴胺、5-羟色胺)对凡纳滨对虾(Litopenaeus vannamei)离子转运酶活力和渗透压的影响。结果表明:注射生物胺(DA、5-HT)对凡纳滨对虾鳃丝总AT- Pase、Na -K -ATPase、V-ATPase活力的影响均显著(P<0.05).而对HCO3--ATPase活力和渗透压的影响不显著(P>0.05),而对照组渗透生理指标无明显变化。注射DA组AT- Pase、Na -K -ATPase活力在6h内呈峰值变化,分别在1h、3h达到最大值,在6-12h时稳定在对照组水平,12h后逐渐升高,于36h时达到最大值后降低,而V-ATPase活力在实验时间内呈阶段式升高现象,在36h达最大值后降低;注射5-HT组ATPase、Na -K -ATPase活力随取样时间增加而降低.至9h达到最小值,9h后趋于稳定,V-ATPase活力在48h内与对照组差异不显著。注射DA、5-HT处理组血淋巴渗透压分别在6h、9h内呈明显的峰值变化.分别在1h、6h达到最大值,然后分别在6h、9h后趋于稳定,并恢复至对照组水平。  相似文献   
8.
Abstract. A new concept (‘enzyme sharing’) concerning the interaction of marine nematodes and microbes in the degradation of sedimentary detritus is presented. Elements of this concept are (1) the notorious tendency of many aquatic nematodes to agglutinate detrital particles by mucus secretions, (2) new observations on the stimulation of microbial growth by nematodes in agar plates, and (3) literature data on limited endogenous proteolytic capacities of aquatic nematodes.
Observations on nematode‐microbe associations in agar plates prompted the conceptual synthesis. In agar medium without the addition of any nutrients a spectacular growth of bacteria was visible on the sinusoidal crawling trails of nematodes only 2 – 3 days after introduction of the worms (species of Adoncholaimus, Anoplostoma and Sabatieria). Juveniles of Anoplostoma that hatched in the agar cultures left their minute trails in the medium and these were rapidly occupied by bacteria. The nematodes repeatedly visited their bacterial trails, which persisted as a peculiar biotic structure for more than one year and survived the nematodes.
In sterile agar preparations containing the fluorogenic methylumbelliferyl‐β‐glucoside in the presence of the nematode Adoncholaimus, an enhanced fluorescence of the medium was visible, indicating β‐glucosidase activity. We therefore assume that oncholaimid nematodes discharge enzymes that alone, or in concert with microbial activities, contribute to the hydrolytic cleavage of refractory polysaccharides containing β‐glucosidic bonds such as agar components and cellulose. The sugars thus produced may then be taken up by the nematodes and concomitantly support the conspicuous growth of microbes. Since we did not observe any feeding of the nematodes on the associated microbes in agar plates, we question the nutritive potential of intact microbial cells for a number of nematodes abounding in detrital habitats, and call attention to the significance of ambient dissolved or adsorbed organic monomeric nutrients.
Consequently, we perceive the puzzling perpetual accretion of detrital organic particles to sediment agglutinations by nematodes as an adaptation for operating an ‘enzymatic reactor’ for the production of dissolved nutrients. We hypothesise a relationship of mutual commensalism of nematodes and heterotrophic microbes in detrital habitats and propose the term ‘enzyme sharing’ for this relationship. Both parties invest in a common enzyme pool that decomposes organic detritus for their nutrition. We present here evidence that nematodes contribute β‐glucosidase, which is involved in the cellulase system. Data from the literature suggest that microbial enzymatic processing of detrital proteins yields amino acids available to nematodes, which apparently have no efficient proteolytic enzyme system in their intestines.  相似文献   
9.
The effect of size and tissue parts as well as site locations on a suite of six anti-oxidative biochemical markers, viz. the enzyme degrading neural transmitters acetylcholinesterase (AChE), the Phase II transforming enzyme glutathione-S-transferase (GST), the anti-oxidative enzymes superoxide dismutase (SOD) and catalase (CAT), the lipid metabolite malondialdehyde (MDA) and the ratio of CAT/MDA, in the bivalve mollusc, Perna viridis, was studied. Field mussels were collected from the piers of University of Science and Technology (UST), Pak Sha Wan or Hebe Haven (PS) and Sai Kung (SK) in Port Shelter, Hong Kong. Statistically, ANOVA showed that the activity of all six biochemical markers were generally tissue dependent, size independent and location dependent. Tukey multi comparison test indicated that the biochemical activities fell into two groups, with SK the highest activity group in most cases. The significance of these findings in relation to long-term coastal water biomonitoring is discussed.  相似文献   
10.
温度对刺参繁殖期消化酶和代谢酶活力的影响   总被引:1,自引:0,他引:1  
为探究刺参(Apostichopus japonicus)繁殖期消化、代谢生理特点,作者以刺参亲参(240 g±15 g)为实验材料,设置了5个温度水平(6、10、14、18、21℃),研究了温度对刺参繁殖期内肠道消化酶和体壁肌肉代谢酶活力的影响。结果发现:温度对亲参繁殖期消化酶、代谢酶活力受培育水温影响显著(P0.05)。其中,胰蛋白酶与淀粉酶活力随水温升高呈先升高后降低的趋势,在10℃时活力最高且达到峰值;脂肪酶活力随着养殖水温升高呈下降趋势,在6℃时活力最高。己糖激酶、丙酮酸激酶、乳酸脱氢酶、苹果酸脱氢酶活力随水温升高出现先增高后降低的趋势,在10℃时达到峰值;而琥珀酸脱氢酶活力随温度升高呈下降趋势。研究表明,10~14℃温度下,亲参消化酶与代谢酶活力均处于较高水平,是理想的亲参室内促熟温度参数。  相似文献   
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