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转“全鱼”溶菌酶基因大菱鲆的研究 总被引：7，自引：0，他引：7
用大西洋条鳕(Macrozoarces americanus)抗冻蛋白启动子opAFP promoter和牙鲆(Paralichthys olivaceus)c型溶菌酶基因构建“全鱼”溶菌酶基因元件opAFP—ly，首次应用电脉冲精子介导法将该基因片段导入到大菱鲆(Scophthalmus maximus)受精卵内，获得原代转基因大菱鲆。先后采用单因子方法和正交实验方法，重复实验确定了最适导入条件：脉冲电压为400V／cm，脉冲次数为5，脉冲宽度为25ms，外源DNA浓度为50mg/L。利用最适导入条件，实现基因元件大规模转移。采用PCR技术对1月龄的原代转基因大菱鲆仔鱼的染色体DNA进行分析，结果表明外源基因的整合率可达28％。 相似文献
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We extracted marine low-temperature lysozyme (MLTL), a novel lysozyme, from a marine microorganism through fermentation. Our
previous study suggested that a low molecular weight (16 kDa) may exert anti-tumor activity through antiangiogenesis. In this
study, we extracted a high weight (39 kDa) and investigated its antiangiogenic activity in vivo and in vitro. Using zebrafish embryos as an in vivo study model, we found that treatment with MLTL significantly inhibited the growth of subintestinal vessels (SIVs) in a dose-dependent
manner and that 400 μg/ml MLTL was sufficient to block the growth of SIVs. An in vitro study conducted using human umbilical vein endothelial cells (HUVECs) revealed that MLTL suppressed the proliferation, migration
and tube formation of HUVECs in a dose-dependent manner. Interestingly, assays by flow cytometry and DNA electrophoresis indicated
that MLTL was able to induce apoptosis of HUVECs. Moreover, further study demonstrated that the disruption of intracellular
Ca2+ homeostasis may play an important role in MLTL induced apoptosis of HUVECs. Taken together, the results of this study demonstrate
for the first time that MLTL inhibits angiogenesis through its pleiotropic effects on vascular endothelial cells and induces
apoptosis through regulation of cellular Ca2+ levels. The results of this study also revealed a possible mechanism underlying the antiangiogenic effect of MLTL and suggested
that MLTL may be a promising new antiangiogenic agent for use in cancer therapy. 相似文献
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以大黄鱼（Larimichthys crocea）为研究对象,研究急性、慢性低盐度胁迫对大黄鱼存活状况及非特异性免疫酶活力的影响。结果表明：急性低盐（15、8）胁迫下,在7 d的实验周期中,大黄鱼肝脏的超氧化物歧化酶（superoxide dismutase, SOD）活力呈先上升后下降的趋势,在第1天显著上升（p<0.05）后逐渐下降至显著低于对照组水平;肝脏的过氧化氢酶（catalase, CAT）活力整体呈先下降后上升再下降的趋势,在第1天显著下降后开始升高,第3天后开始下降,至第7天时CAT活力仍显著低于对照组水平;血清中的酸性磷酸酶（acid phosphatase, ACP）活力呈下降后逐渐升高的趋势,在第1 天时显著下降后逐步升高,至第7天时仍显著低于对照组;而血清中的碱性磷酸酶（alkaline phosphatase, ALP）活力在实验开始的第1天到第3天逐渐升高,且均显著高于对照组,至第7天时开始下降至对照组水平;血清中的溶菌酶（lysozyme, LZM）含量呈波动变化,整体呈先上升后下降趋势。慢性低盐（8）养殖14 d后,大黄鱼的各项非特异性免疫酶活力均与对照组无显著性差异（p>0.05）。此外,实验周期内所有组别大黄鱼均未出现死亡,仅急性低盐胁迫组大黄鱼的活动和摄食受到有限影响。大黄鱼对慢性降盐度养殖有较高的耐受能力,而盐度骤降会显著影响大黄鱼的非特异性免疫,实际生产中应避免养殖环境盐度的剧烈变化。 相似文献
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动物型溶菌酶研究新进展 总被引：3，自引：0，他引：3
溶菌酶可以分解连接N-乙酰胞壁酸(NAM)和N-乙酰氨基葡萄糖(NAG)残基之间的β-1,4糖苷键。g型、c型和i型溶菌酶是3种动物型溶菌酶。近年来,越来越多的报道表明这3种类型的溶菌酶在动物界广泛存在,g型和c型溶菌酶主要存在于脊椎动物中,i型溶菌酶仅存在于无脊椎动物中,部分物种中同时存在2种动物型溶菌酶。本文简要概述了溶菌酶在动物各物种中的存在情况和组织分布情况、基因组结构与系统进化以及溶菌酶抑制剂的研究新进展。 相似文献
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盐度对日本鳗鲡生长及非特异性免疫酶活性的影响 总被引：2，自引：0，他引：2
利用实验生态学和酶学方法,在浙江省海洋水产养殖研究所清江试验场研究了盐度对平均体长为25．1±5．6cm的日本鳗鲡（Anguillajaponica）生长及其血清溶茵酶（LZM）、超氧化物歧化酶（SOD）及碱性磷酸酶（AKP）活性的影响,实验持续60d．实验设置了5个盐度梯度（盐度5、10、15、20、25）和对照组（盐度0）,每梯度设3个平行组,各组盐度和pH值保持一致．日本鳗鲡血清中免疫酶活力指标：碱性磷酸酶、溶茵酶、超氧化物歧化酶在实验的第7天和第14天测定．实验结果表明,盐度5组相对增重率最高（279．78％±28．37％）,其次是盐度10组（278．74％±22．25％）,盐度15、20、25组相对增重率分别为234．39％±21．28％、230．28％±26．31％、228．01％±29．29％．对照组相对增重率为233．20％-4-25．18％,盐度5和10组与对照组差异显著（P〈0．05）,其余各组与对照组差异不显著．第7天和第14天,盐度10组碱性磷酸酶活性最高,分别为225．05U／dm。和251．11U／dm’,其次是盐度5组,分别为221．76U／dm。和236．01U／dm。,显著高于对照组（P〈0．05）．第7天和第14天盐度20、25组溶菌酶活性显著高于对照组（P〈0．01）．超氧化物歧化酶随着盐度的升高呈逐步上升趋势．第14天,盐度20、25纽溶菌酶活性仍保持较高水平,SOD回落至对照组水平,而各组AKP较第7天略有上升． 相似文献
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根据研究证明,在机体先天免疫系统中溶菌酶作为重要的效应分子之一,通过参与机体中多种免疫反应,主要是通过形成一个水解体系,从而破坏和消除侵害体内的病原体,进而促使机体实现免疫防御。本研究以生活在深海超深渊海沟极端环境下的钩虾Eurythenes gryllus为材料,首次从Eurythenes gryllus中克隆获得i型溶菌酶(i-type lysozyme)基因EgLyz。序列分析表明,基因EgLyz与已知序列相似性较低,并含有一个失稳酶结构域。综合分析结果表明EgLyz可能是一个新颖的溶菌酶蛋白。在此基础上,对基因EgLyz进行了大肠杆菌原核重组表达,成功获取了较高纯度的可溶性表达产物,为后续生物活性分析奠定了实验基础。 相似文献
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Immunostimulants may improve disease resistance of aquaculture animals by promoting the nonspecific immunity response of the
organisms. Five types of saccharides, including chitosan, yeast polysaccharide, burdock oligosaccharide, seaweed polysaccharide
and lentinus edodes polysaccharide, were screened for potential use as immunostimulants by using spectrophotometry. The saccharides
were injected into Apostichopus japonicus, a sea cucumber, and the lysozyme and superoxide dismutase (SOD) activities of the coelomic fluid and epidermal slime were
monitored in six consecutive days. The results show that the lysozyme activity of the animal’s coelomic fluid was significantly
stimulated on day 2, day 4 and day 6 after the injection of the saccharides (P<0.05). The effects of chitosan and yeast polysaccharide were the most notable. The lysozyme activity of the epidermal slime
was significantly increased by chitosana, yeast polysaccharide, seaweed polysaccharide, and burdock oligosaccharide on day
1 and day 2 after the injection (P<0.05). The SOD activity of the coelomic fluid was significantly promoted by the saccharides on day 2 and day 4 post-injection
(P<0.05), while the SOD activity of the epidermal slime increased on day 2. These findings indicate that chitosan and yeast
polysaccharide are the most effective immunostimulants and potential healthy anti-disease feedstuff for A. japonicus.
Supported by the National Key Technology Research and Development Program (863 Program, No. 2006BAD09A06) and the Special
Fund of Chinese Central Government for Basic Scientific Research Operations in Commonweal Research Institutes (No. 02-2007B03) 相似文献
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一种复方中草药饲料添加剂在红笛鲷网箱养殖中的应用 总被引：1，自引：1，他引：0
将黄芪、当归、甘草和山楂等粉碎后按一定比例配伍制成复方中草药饲料添加剂后,按质量分数0.5%、1.0%、1.5%和2.0%添加到基础饲料中,连续投喂红笛鲷(体重234.95±19.26 g,体长24.76±1.42 cm)56 d,研究复合中草药制剂对红笛鲷生长、成活、免疫和抗病力的影响。结果表明,基础饲料中添加本复方中草药饲料添加剂能够显著促进红笛鲷的生长,增强其血清中的抗菌活力和溶菌酶活力,提高红笛鲷成活率及其对溶藻弧菌的免疫保护率,其中以添加1.5%(质量分数)和连续饲喂28 d效果为最佳(P<0.01)。 相似文献
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Adriana Giangrande Margherita Licciano Roberto Schirosi Luigi Musco Loredana Stabili 《Marine Ecology》2014,35(1):36-45
In the marine environment, sessile invertebrates have developed an impressive array of mechanisms to avoid predation, bacterial exploitation, and epibiotic overgrowth. In the present study we investigated several defensive strategies adopted by six sabellids: the hard bottom species Sabella spallanzanii (Gmelin, 1791), Branchiomma luctuosum Grube, 1869, Branchiomma bairdi (McIntosh, 1885), and Sabellastarte spectabilis (Grube, 1878), and the soft bottom species Myxicola infundibulum (Renier, 1804), and Megalomma lanigera (Grube, 1846), which have different morphological characteristics and geographical distribution. We examined and compared some defensive features such as branchial crown toughness, tube structure and strength, amount of released mucus, and antibacterial lysozyme‐activity in the mucus. The investigated species utilize a combination of defence and deterrence strategies that seems to be related to the colonized habitat. Tube strength was, higher in the hard bottom species compared with the soft bottom ones, where the tubes are generally buried and protected within the sediment. Branchial crown appeared stronger and resistant in hard bottom species, except for S. spallanzanii, which is the species showing the strongest tube. Sabella spallanzanii, M. infundibulum and S. spectabilis secreted high amount of mucus with high lysozyme‐like activity. By contrast, B. luctuosum, B. bairdi, and M. lanigera produced low amounts of mucus exerting lower antibacterial activity. 相似文献