52 resultados para Heat-shock Response


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Heat shock proteins (Hsps) are molecular chaperones that help organisms cope with stressful conditions. Here, we report on the growth rates and Hsp70 expressions in inbred and hybrid populations of abalone Haliotis discus hannai Ino. In abalone, inbred populations expressed more Hsp70 than hybrid populations at all temperatures, except at very high temperatures close to the physiological limit. At benign temperatures, there was a clear trend towards higher Hsp70 expression in inbred than hybrid populations, whereas at higher temperatures, a trend in the opposite direction was observed. The temperature of maximal Hsp70 expression (T-peak) varied with the population type. The T-peak of inbred populations (26 degrees C) was lower than that of the hybrid populations (28 degrees C). The maximal inducible Hsp70 of inbred populations was higher than that of hybrid populations. The results showed a trend towards higher expression in inbred population at a lower temperature. These results provide direct experimental evidence that hybrids can cope with the intrinsic stress even at non-stressful temperatures. The constitutive Hsp70 may therefore be used for marker-assisted selection in a breeding programme.

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Heat shock protein 22 (HSP22) is an important member of small heat shock protein (sHSP) subfamily which plays a key role in the process of protecting cells, facilitating the folding of nascent peptides, and responding to stress. In the present study, the cDNA of HSP22 was cloned from Argopecten irradians (designated as AiHSP22) by rapid amplification cDNA end (RACE) based on the expressed sequence tags (ESTs). The full-length cDNA of AiHSP22 was of 1,112 bp, with an open reading frame of 588 bp encoding a polypeptide of 195 amino acids. The deduced amino acid sequence of AiHSP22 showed high similarity to previously identified HSP22s. The expression patterns of AiHSP22 mRNA in different tissues and in haemocytes of scallops exposed to Cd2+, Pb2+ or Cu2+ were investigated by real-time quantitative RT-PCR. The mRNA of AiHSP22 was constitutively expressed in all examined tissues, including haemocyte, muscle, kidney, gonad, gill and heart. The expression level in heart and muscle was higher than that in other tissues. The mRNA level of AiHSP22 in haemocytes was up-regulated after a 10 days exposure of scallops to Cu2+, Pb2+ and Cd2+. However, the expression of AiHSP22 did not increase linearly along with the rise of heavy metal concentration. Different concentrations of the same metal resulted in different effects on AiHSP22 expression. The sensitive response of AiHSP22 to Cu2+, Pb2+ and Cd2+ stress indicated that it could be developed as an indicator of exposure to heavy metals for the pollution monitoring programs in aquatic environment.

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We used microarray technology to study differentially expressed genes in white spot syndrome virus (WSSV)-infected shrimp. A total of 3136 cDNA targets, including 1578 unique genes from a cephalothorax cDNA library and 1536 cDNA clones from reverse and forward suppression subtractive hybridization (SSH) libraries of Fenneropenaeus chinensis, plus 14 negative and 8 blank control clones, were spotted onto a 18 x 18 mm area of NH2-modified glass slides. Gene expression patterns in the cephalothorax of shrimp at 6 h after WSSV injection and moribund shrimp naturally infected by WSSV were analyzed. A total of 105 elements on the arrays showed a similar regulation pattern in artificially infected shrimp and naturally infected moribund shrimp; parts of the results were confirmed by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR). The up-regulated expression of immune-related genes, including heat shock proteins (HSP70 and HSP90), trehalose-phosphate synthase (TPS), ubiquitin C, and so forth, were observed when shrimp were challenged with WSSV. Genes including myosin LC2, ATP synthase A chain, and arginine kinase were found to be down-regulated after WSSV infection. The expression of housekeeping genes such as actin, elongation factor, and tubulin is not stable, and so these genes are not suitable as internal standards for semiquantitative RT-PCR when shrimp are challenged by WSSV. As a substitute, we found that triosephosphate isomerase (TPI) was an ideal candidate of interstandards in this situation.

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用生物和非生物因子来进行采后病害的防治,是一个非常有效的方法。诱导抗性作为控制果蔬采后病害的生物技术,已成为该领域的一个研究热点。然而诱导抗性的机制非常复杂,涉及到寄主、病原菌、激发子之间的相互作用关系。本研究主要利用酵母拮抗菌Pichia membranefaciens和SA处理果实,观察其抗性诱导表达和对采后青霉病菌(Penicillium expansum)的抑制作用,并从蛋白质组学水平上对诱导抗性的机理进行了分析。研究结果表明: 1、酵母拮抗菌P. membranefaciens (5 × 107 cells·ml-1)和SA(0.5 mM)处理采后甜樱桃果实,能够明显地降低病害的发病率和病斑直径。酵母菌和SA处理影响到了果实抗氧化酶的活性,同时还改变了POD同工酶谱和甜樱桃果实的总蛋白含量,并诱导了新的蛋白质条带产生。用光学显微镜和扫描电子显微镜技术观察发现,在in vitro条件下P. membranefaciens能够紧密地结合与病原菌的菌丝,而在in vivo条件下这种结合较为松散。 2、借鉴其它模式植物的方法,我们建立了一整套适用于多汁类植物材料的蛋白质组学研究方法。对于芒果,桃,甜樱桃、苹果以及冬枣等果实,都取得了重复性非常好的2-D图谱。我们应用该技术进一步研究了P. membranefaciens (1 × 108 cells·ml-1)以及SA (0.5 mM)处理对桃果实蛋白质组的诱导影响。结果显示,两种激发子处理都能够诱导桃果实产生抗性,从而减轻青霉病引起的腐烂。在诱导处理1 d以后,酵母拮抗菌和SA分别诱导22和16个蛋白的差异表达。质谱鉴定的蛋白属于6大类:代谢,防御反应,转录,能量途径以及细胞结构。有6个蛋白受到两种激发子的共同调控。其中,4种蛋白(包括glutathione peroxidase, polyphenol oxidase precursor, catalase和methionine sulfoxide reductase) 属于抗氧化蛋白,涉及到活性氧代谢。另2个蛋白(Major allergen Pru av 1和peroxidase)是病程相关蛋白,直接参与植物的防御反应。同时一些磷酸化酶和转录因子也受到两种激发子的调节从而参与果实的抗病反应。酶学测定和Northern杂交的结果表明,拮抗菌与SA处理均能影响过氧化氢酶活性及其基因的表达。 3、采前用较高浓度SA (2 mM) 短时间(10s)处理不同成熟期的甜樱桃果实,能够明显降低果实青霉病的病斑直径,并能减轻较低成熟度果实的发病率。在没有接菌的情况下,SA诱导了33个差异表达的蛋白,其中用质谱鉴定出了26个。而在接种病原菌的情况下,SA诱导了19个差异表达的蛋白,并鉴定出了其中的12个。这些蛋白分别涉及到代谢、防御反应、转录、能量途径、信号转导等过程。在没有接种病原菌的情况下,SA处理诱导了Putative DnaJ heat shock protein, PR1-like protein, Peroxidase, Major allergen Pru av 1 (Pru a 1)和Catalase等与抗病有关的蛋白。而在接种病原菌的情况下,诱导了PR1-like protein, Peroxidase和Catalase蛋白的差异表达。通过酶活性测定以及对细胞学定位的研究,我们发现在没有接种病原菌的情况下,POD的活性受到SA的诱导。但是在接种病原菌以后,诱导效果不明显。

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热激蛋白90是广泛存在于各类细菌和真核生物中的一类高度保守的分子伴侣,它对维持细胞生命是绝对必需的。对Hsp90的相关认知主要来源于对动物和酵母细胞的研究,植物Hsp90的研究甚少。由于植物的特殊性,因此对植物Hsp90的研究是对Hsp90未知功能的有力补充。拟南芥中有7个Hsp90蛋白,其中AtHsp90-1、AtHsp90-2、AtHsp90-3和AtHsp90-4定位在细胞质中,AtHsp90-5、AtHsp90-6和AtHsp90-7分别定位在叶绿体、线粒体和内质网中。本文对拟南芥中的AtHsp90-1、AtHsp90-2、AtHsp90-5、AtHsp90-6和AtHsp90-7五个基因进行了克隆,并分别利用酵母互补、双杂交和拟南芥过表达体系几个层面进行了功能分析。 我们利用酵母穿梭载体p416GPD构建了五个AtHsp90基因的酵母表达载体,将其转入Hsp90基因点突变和条件型缺失的酵母菌株iG170D和R0005中。酵母功能互补实验表明细胞质定位的AtHsp90-1和AtHsp90-2可以在各种胁迫条件下互补酵母Hsp90的功能,而定位于细胞器中的AtHsp90-5、 AtHsp90-6和AtHsp90- 7则在任何条件下都不能互补酵母Hsp90的功能。我们还对转基因酵母进行了液体培养的动态观测和细胞膜完整性检测,其结果和固体培养的结果一致。这说明细胞质Hsp90的功能具有一定的保守性,细胞器Hsp90的功能有其特殊性。 热激蛋白90在执行其生物功能时,需要和大量的辅助因子相互作用,因此我们利用酵母双杂交体系检测了AtHsp90-1、AtHsp90-2、AtHsp90-5、AtHsp90-6和AtHsp90-7五个Hsp90蛋白和Hsp70、p23、Cyp40、NOS等几个辅助因子之间的相互作用情况。双杂交结果显示AtHsp90-1和AtHsp90-2几乎不和所选的这几个辅助因子相互作用,AtHsp90-5可以和所有的辅助因子相互作用、AtHsp90-6可以和除Hsp70以外的辅助因子相互作用,AtHsp90-7也可以和所有的辅助因子相互作用但和Hsp70及Hsp70t-2和互作较其他辅助因子弱一些。可以看出胞质Hsp90和细胞器Hsp90在和辅助因子相互作用时有一定的差异。 为了进一步了解拟南芥个Hsp90基因在抗非生物逆境中的作用,我们又将AtHsp90-2、AtHsp90-5、AtHsp90-7基因插入植物表达载体pBI121,用农杆菌介导的浸蕾法将这三个基因转入拟南芥并在其中过量表达,并研究了这些基因的过表达植株的种子和幼苗对多种模拟非生物逆境的响应。结果显示,转基因种子和幼苗对ABA、盐(NaCl)、干旱(甘露醇)、高温、氧化、高钙等非生物逆境都表现出了敏感,转细胞器Hsp90的种子和幼苗比转细胞质Hsp90的更为敏感。但在高浓度钙离子胁迫下,幼苗表现情况与盐、旱和氧化等非生物逆境处理下的情况正好相反,转细胞器Hsp90的幼苗比转细胞质Hsp90的长得健壮。这些结果表明Hsp90参与了植物抵抗非生物逆境的反应,其作用可能是通过ABA和Ca2+途径实现的,然而体内Hsp90的动态平衡可能才是植物抵抗非生物逆境的关键。

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The heme-regulated initiation factor 2 alpha kinase (HRI) is acknowledged to play an important role in translational shutoff in reticulocytes in response to various cellular stresses. In this study, we report its homologous cDNA cloning and characterization from cultured flounder embryonic cells (FEC) after treatment with UV-inactivated grass carp haemorrhagic virus (GCHV). The full-length cDNA of Paralichthys olivaceus HRI homologue (PoHRI) has 2391 bp and encodes a protein of 651 amino acids. The putative PoHRI protein exhibits high identity with all members of eIF2 alpha kinase family. It contains 12 catalytic subdomains located within the C-terminus of all Ser/Thr protein kinases, a unique kinase insertion of 136 amino acids between subdomains IV and V, and a relatively conserved N-terminal domain (NTD). Upon heat shock, virus infection or Poly PC treatment, PoHRI mRNA and protein are significantly upregulated in FEC cells but show different expression patterns in response to different stresses. In healthy flounders, PoHRI displays a wide tissue distribution at both the mRNA and protein levels. These results indicate that PoHRI is a ubiquitous eIF2a kinase and might play an important role in translational control over nonheme producing FEC cells under different stresses. (c) 2006 Elsevier Ltd. All rights reserved.

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Heat shock protein 70 (HSP70), the primary member of HSPs that are responsive of thermal stress, is found in all multicellular organisms and functions mostly as molecular chaperon. The inducible HSP70 cDNA cloned from Pacific abalone (Haliotis discus hannai) using rapid amplification of cDNA ends (RACE), was highly homologous to other HSP70 genes. The full-length cDNA of the Pacific abalone HSP70 was 2631 bp, consisting of a 5'-terminal untranslated region (UTR) of 90 bp, a 3'-terminal UTR of 573 by with a canonical polyadenylation signal sequence AATAAA and a poly (A) tail, and an open reading frame of 1968 bp. The HSP70 cDNA encoded a polypeptide of 655 amino acids with an ATPase domain of 382 amino acids, the substrate peptide binding domain of 161 amino acids and a C-terminus domain of 112 amino acids. The temporal expression of HSP70 was measured by semi-quantitative RT-PCR after heat shock and bacterial challenge. Challenge of Pacific abalone with heat shock or the pathogenic bacteria Vibrio anguillarum resulted in a dramatic increase in the expression of HSP70 mRNA level in muscle, followed by a recovery to normal level after 96 h. Unlike the muscle, the levels of HSP70 expression in gills reached the top at 12 h and maintained a relatively high level compared with the control after thermal and bacterial challenge. The upregulated mRNA expression of HSP70 in the abalone following heat shock and infection response indicates that the HSP70 gene is inducible and involved in immune response. (c) 2006 Elsevier Ltd. All rights reserved.

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本文研究粘弹性材料界面裂纹对冲击载荷的瞬态响应和对广义平面波的稳态散射。相对于已有广泛研究的弹性材料裂纹瞬态响应和稳态散射问题,本文的研究有三个突出特点:1)粘弹性材料;2)界面裂纹;3)广义平面波入射。粘弹性材料界面裂纹对冲击载荷的瞬态响应和对广义平面波的散射尚无开展研究,本文在弹性材料相应问题的研究基础上,首先开展了这一问题的研究。对于冲击载荷下粘弹性界面裂纹的瞬态响应问题,利用Laplace积分变换方法,将粘弹性材料卷积型本构方程转化为Laplace变换域内的代数型本构方程,从而可以在Laplace变换域内象处理弹性材料的冲击响应一样,将相应的混合边值问题归结为关于裂纹张开位移COD的对偶积分方程,并进一步引入裂纹位错密度函数CDD (Crack Dislocation Density),将对偶积分方程化成关于CDD的奇异积分方程(SIE)。用数值方法求解奇异积分方程得到变换域内的动应力强度因子数值解,最后利用Laplace积分逆变换数值方法得到时间域内的动应力强度因子的时间响应。理论分析考虑了两种裂纹模型,即Griffith界面裂纹和柱面圆弧型界面裂纹。考虑的载荷包括反平面冲击载荷和平面冲击载荷。对于平面冲击载荷,通过对裂尖应力场的奇性分析,首次发现粘弹性界面裂纹裂尖动应力场奇性指数不是常数0.5,而是与震荡指数一样依赖材料参数。针对反平面冲击载荷给出了一个算例,计算了裂尖动应力强度因子的时间响应,并与弹性材料的结果作了比较,发现粘弹性效应的影响不仅使过冲击峰值降低,而且使峰值点后移。粘性效应较大时,过冲击现象甚至不出现。关于粘弹性界面裂纹对广东省义平面波的散射问题,首先研究广义平面波在无裂纹存在的理想界面的反射和透射,再研究由于界面裂纹的存在而产生的附加散射场。利用粘弹性材料的复模量理论,可将粘弹性材料的卷积型相构方程化成频率域内的代数型本构方程。类似弹性平面波的处理,在频率域内将问题最终归结为关于裂纹位错密度CDD的奇异积分方程。数值方法求解奇异积分方程即可得到频率域内的散射场,并进而得到裂尖动应力强度因子和远场位移型函数和散射截面。理论分析考虑了两种裂纹模型:Griffith界面裂纹和柱面圆弧型界面裂纹。研究的入射波有广义的SH波和P波。对于广义平面P波入射的情况,通过对裂尖应力场的奇性分析,同样发现粘弹性界面裂纹裂尖动应力场奇性指数不地常数0.5,而是与震荡指数一样依赖于材料参数。对柱面裂纹散射远场的渐近分析,发现远场位移和应力除含有几何衰减因子外,都含有一个材料衰减速因子。散射截面由于材料衰减因子的存在也成为依赖散射半径的量。为了使散射截面仍有意义,文中提出一种修正办法。对Griffith界面裂纹,给出了一个广义平面SH波入射的算例;对柱面界面裂纹,给出了一个广义平面P波入射的算例。计算了不同入射角和入射频率下裂纹的张开位移和动就应力强度因子,并分析了其依赖关系。求解奇异积分方程的数值方法和Laplace积分逆变换数值方法是本文的基本数值方法。本文对这两种方法作了大量的调研和系统的研究。在对比分析的基础上,对现有的各种方法从原理,适用范围,计数效率,优势及特点进行了归纳总结。并尝试了奇异积分方程的最新数值方法--分片连续函数法,证实了其适用性和方便性.

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随着人类基因组计划的完成,蛋白质组学研究已成为生命科学乃至自然科学中最活跃的学科领域之一。蛋白质组学将对我们理解后基因组学时代的基因功能有极大的帮助。差异表达蛋白质组学通过对不同样品蛋白质表达水平的比较,已经被广泛地应用在疾病的研究领域。P糖蛋白已经被证实参与介导了在急性粒白血病中发生的多药耐药,然而越来越多的研究结果表明,在急性粒白血病中多药耐药的机制是多因素的。为了寻找白血病肿瘤细胞中与耐药相关的靶蛋白,我们采用蛋白质组学研究技术,对多药耐药细胞系K562/A02的蛋白质表达谱进行了分析。 本研究采用蛋白质组学研究技术,对多药耐药细胞系K562/A02和药物敏感细胞系K562/S的总蛋白质进行双向凝胶电泳(2 DE)的差异分析,结果发现在K562/A02细胞中有41个蛋白质点差异显著,并用基质辅助激光解离飞行时间质谱(MALDI-MS)成功鉴定了大多数的蛋自点。在被鉴定出的差异蛋白质中,有一些是首次发现与耐药相关,包括chloride intracellular charmel,chaperonin,proteindisulfide-isomerase ER6o precursor and constitutive heat shock protein 70等。所得结果不但能够使我们更加深入的理解肿瘤耐药的病理机制,更重要的是通过找到肿瘤细胞发生耐药的标志性蛋白,可以为开发肿瘤耐药预测方法和寻找抗耐药肿瘤靶标新药的线索,同时也为计算机虚拟筛选设计抗耐药肿瘤新药奠定基础。除了详细的研究了K562/A02细胞系差异蛋白质组,我们还采用蛋白质组学的方法,以乳鼠心肌细胞为实验模型,研究在ARs激动的不同清况下心肌细胞蛋白质表达谱的变化。心肌肥厚是心脏工作超负荷的一种代偿反应。目前,越来越多的证据表明ARs在心肌肥厚的发生中起着非常重要的作用,但人们对其机制了解尚不全面。通过检测心肌肥厚时全蛋白表达的变化,将有助于我们全面、深入了解ARs在心肌肥厚中的作用机制。通过严格的2D胶图象分析,蛋白取点后胶内水解,高灵敏度的质谱鉴定及数据库检索,我们成功地进行了乳鼠心肌细胞肥厚为模型的蛋白质组学的研究。本实验通过比较研究不同肾上腺素受体激动剂norePinephrine伽E),phenylephxine(PE)and isoprenaline(ISO)诱导组与未诱导对照组的蛋白质组学变化,分析确定蛋白丰度差异在2倍以上的蛋白质点,并通过MALDI-MS进行蛋白鉴定。20个具有显著差异的蛋白质被鉴定,包括caspase-11,vimeniin,4-hydroxyphenylpyruvic acid dioxygenase,Modl protein,Txndcs protein等,其中一些蛋白在此之前并没发现与心肌肥厚相关,对它们在心肌肥厚中的意义和机制我们将做进一步的探讨。本研究结果将为我们更好理解肾上腺素受体之间以及肾上腺素受体与心肌肥厚之间的关系提供有益的线索,并将为最终发现可应用于临床的新的诊断和治疗心血管疾病的标志性蛋白打下基础。

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近年来,我国炼油行业发展迅速,炼油能力全世界第二,炼油行业已成为污染大户。本研究针对炼油废水生物处理中存在的稳定达标难、抗冲击负荷能力差、建设投资与运行成本高等问题,就菌剂强化处理炼油废水中试与工程应用展开了研究,以期为菌剂的工程应用与推广提供理论参考与技术支持;并以炼油废水中的主要特征污染物苯酚为研究对象,考察了不同浓度苯酚冲击下功能菌的响应机制,并以此为指导研制功能菌激活促进剂,考察其对功能菌生物学指标的调控效果,以期为废水生物处理有毒污染物冲击调控提供理论依据与技术支持。 中试研究表明,菌剂强化处理炼油废水,出水COD、NH4+-N 平均值为86.7、7.6 mg/L,其平均去除率较常规生物处理系统分别提高了35.47%、59.28%,其耐受COD、NH4+-N 容积负荷分别高达2.42、0.139kg/(m3·d),具有良好的耐冲击能力。工程应用研究表明,菌剂强化处理炼油废水,出水COD、NH4+-N 平均值分别为85.05、8.4mg/L,其去除率较常规生物处理系统提高了25.1%、28.7%,出水水质各项指标均达到了国家《污水综合排放标准GB 8978-1996》一级排放标准。技术经济分析表明,菌剂强化处理炼油废水在建设成本、运行成本上分别降低38%、49%,具有良好的技术经济优势。 苯酚冲击下功能菌响应机制研究表明:不同浓度苯酚冲击下,生物学指标生物量、脱氢酶酶活、1,2-双加氧酶酶活对冲击都有不同程度的响应,其响应敏感程度为脱氢酶酶活>生物量>1,2-双加氧酶酶活。1,2-双加氧酶酶活与COD 降解率相关性良好,可表征苯酚降解过程,确认为调控重点。以此为指导研制出苯酚降解功能菌抗冲击激活促进剂,可有效调控功能菌对有毒污染物苯酚的降解效果,1000mg/L 苯酚冲击下,经调控,其COD 去除率较对照提高20%,降解时间缩短16%以上。其对生物学指标的调控效果为1,2-双加氧酶酶活>生物量>脱氢酶酶活,验证了功能菌在苯酚冲击下的响应机制。研究表明菌剂强化处理炼油废水切实可行,具有良好的技术经济优势。有毒污染物冲击下废水生物处理系统响应机制研究为抗冲击调控提供了新的研究思路。 Currently, China’s oil refining industry is developing rapidly and has become the second largest all over the world. The oil refining industry is one of the major pollution industries in our country. The pilot scale study and engineering application research were conducted aiming at the problems in refining wastewater such as poor treatment stability and water quality, poor anti-shock capacity and expensive running cost, etc., so as to provide theoretical references and technological supports for the engineering application and popularization of microbial preparation in wastewater treatment. Also, the response mechanism of functional microbe under shock of different phenol concentrations, which is the main pollutants in refinery wastewater, was studied. Based on this result, functional microbe activation accelerator was developed, and the regulation effect of functional microbe biological index under phenol shocking were studied, in order to provide theoretical basis and technological support for regulation of toxic shocking of wastewater biological treatment. The result of pilot scale research indicated: for treatment of refinery wastewater in bioaugmention treatment system of microbial preparation, the COD and NH4+-N average value of effluent was 86.7 and 7.6 mg/L, Comparing with normal biological treatment system, the average removal rates of COD, NH4+-N increased 35.47%,59.28% separately by bioaugmention treatment system, which showed better anti-shocking capacity, the volumetric load r of COD and NH4+-N reached 2.42 kg/(m3·d) and 0.139 kg/(m3·d), respectively. The research on engineering application of refinery wastewater bioaugmentation treatment by microbial preparation indicated:the average concentrations of effluent COD and NH4+-N in the bioaugmentation treatment system were 85.05 and 8.4mg/L, which increased by 25.1% and 28.7% comparing with normal biological treatment system of refinery wastewater, And the effluent quality meets the first grade of discharging standard of National Integrated Wastewater Discharge Standard GB 8978-1996. The economic analysis of technology indicated: the demonstration project of bioaugmentation treatment of refinery wastewater by microbial preparation decreased by 38% in construction cost and 49% in running cost. This technology has economic benefits. The response mechanism of functional microbe under phenol shock indicated: biological index such as the biomass concentration, dehydrogenase and 1,2-dioxygenase had different responses under phenol shocking of different concentrations. The response sensitivity of different biological index under phenol shocking of different concentrations is: dehydogenase activity > biomass >1,2-dioxygenase activity, and high correlation of 1,2-dioxygenase and COD degradation percentage is achieved, thus 1,2-dioxygenase could be used to reflect the degradation situation of pollutants. So, 1,2-dioxygenase is the keypoint of regulation. The anti-shock activation accelerator of phenol degradation functional microbe was primarily developed. The results indicated: the activation accelerator could regulate the degradation effect of toxic substance-phenol by functional microbe effectively. For the functional microbe treatment system under phenol shocking of 1000mg/L, the COD degradation rate increased by 20% and the degradation time reduced by more than 16% under regulation of activation accelerator. The regulation effects of biological index are: 1,2-dioxygenase > biomass > dehydrogenase. In this way, the response mechanism of functional microbe under toxic shocking is verified. The result indicated: the augmented microbial preparation treatment of refinery wastewater is applicable. It has many technical and economical advantages. The research results of responses mechanism of wastewater treatment system on toxic pollutants would offer a new idea for regulation of anti-shock.

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Both MI and MII triploids were successfully produced by heat shock in Chinese shrimp Fenneropenaeus chinensis. The inducing conditions for MI and MII triploids were optimized. The highest inducing rate obtained for MI triploids reached more than 90%, and that for MII triploids reached nearly 100% at the nauplius stage as evaluated using flow cytometry. Comparisons of survival rates at larval stages between triploids and diploids or diploids experiencing treatment and diploids without treatment were performed. At larval stage from nauplii to postlarvae, heat shocks lowered survival at larval stages even if the ploidy was not changed. Ploidy did not affect shrimp larvae survival, and no significant difference was found in the survival of shrimp larvae between MI and MII triploids. Highly significant differences were observed in the morphology of triploids and diploids, and no apparent difference was found in the morphology of MI and MII triploids at the grow-out stages. Discriminating formulae for triploid and diploid shrimp at grow-out stage were developed and could be used to distinguish triploids from diploids based on morphological parameters. MI and MII triploids of shrimp have the potential to be used in aquaculture.

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Vibrio harveyi is an important marine pathogen that can infect a number of aquaculture species. V. harveyi degQ (degQ(Vh)), the gene encoding a DegQ homologue, was cloned from T4, a pathogenic V. harveyi strain isolated from diseased fish. DegQ(Vh) was closely related to the HtrA family members identified in other Vibrio species and could complement the temperature-sensitive phenotype of an Escherichia coli strain defective in degP. Expression of degQVh in T4 was modulated by temperature, possibly through the sigma(E)-like factor. Enzymatic analyses demonstrated that the recombinant DegQVh protein expressed in and purified from E. coli was an active serine protease whose activity required the integrity of the catalytic site and the PDZ domains. The optimal temperature and pH of the recombinant DegQVh protein were 50 C and pH 8.0. A vaccination study indicated that the purified recombinant DegQVh was a protective immunogen that could confer protection upon fish against infection by V. harveyi. In order to improve the efficiency of DegQVh as a vaccine, a genetic construct in the form of the plasmid pAQ1 was built, in which the DNA encoding the processed DegQVh protein was fused with the DNA encoding the secretion region of AgaV, an extracellular beta-agarase. The E.coli strain harboring pAQ1 could express and secrete the chimeric DegQVh protein into the culture supernatant. Vaccination of fish with viable E. coli expressing chimeric degQ(Vh) significantly (P < 0.001) enhanced the survival of fish against V. harveyi challenge, which was possibly due to the relatively prolonged exposure of the immune system to the recombinant antigen produced constitutively, albeit at a gradually decreasing level, by the carrier strain.

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Vibrio harveyi is an important marine pathogen that can infect a number of aquaculture species. V. harveyi degQ (degQ(Vh)), the gene encoding a DegQ homologue, was cloned from T4, a pathogenic V. harveyi strain isolated from diseased fish. DegQ(Vh) was closely related to the HtrA family members identified in other Vibrio species and could complement the temperature-sensitive phenotype of an Escherichia coli strain defective in degP. Expression of degQVh in T4 was modulated by temperature, possibly through the sigma(E)-like factor. Enzymatic analyses demonstrated that the recombinant DegQVh protein expressed in and purified from E. coli was an active serine protease whose activity required the integrity of the catalytic site and the PDZ domains. The optimal temperature and pH of the recombinant DegQVh protein were 50 C and pH 8.0. A vaccination study indicated that the purified recombinant DegQVh was a protective immunogen that could confer protection upon fish against infection by V. harveyi. In order to improve the efficiency of DegQVh as a vaccine, a genetic construct in the form of the plasmid pAQ1 was built, in which the DNA encoding the processed DegQVh protein was fused with the DNA encoding the secretion region of AgaV, an extracellular beta-agarase. The E.coli strain harboring pAQ1 could express and secrete the chimeric DegQVh protein into the culture supernatant. Vaccination of fish with viable E. coli expressing chimeric degQ(Vh) significantly (P < 0.001) enhanced the survival of fish against V. harveyi challenge, which was possibly due to the relatively prolonged exposure of the immune system to the recombinant antigen produced constitutively, albeit at a gradually decreasing level, by the carrier strain.

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Acid, alkali, heat-shock, KNO3 and control pretreatment methods applied to anaerobic sludge were evaluated for their ability to selectively enrich the marine hydrogen-producing mixed microflora. Seawater culture medium was used as the substrate. The hydrogen yield of pretreated microflora was higher than that of the un-pretreated control (P < 0.05). Among the pretreatment methods studied, heat-shock pretreatment yielded the greatest hydrogen production, which was 14.6 times that of the control. When the effect of initial pH on hydrogen production of heat-shock pretreated samples was studied, hydrogen was produced over the entire pH range (pH 4-10). The hydrogen yield peaked at initial pH 8 (79 mL/g sucrose) and then steadily decreased as the initial pH increased. Sucrose consumption was high at neutral initial pH. During the process of hydrogen production, pH decreased gradually, which indicated that the acquired microflora consisted of acidogenic bacteria.

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In this study, a full-length cytosolic heat shock protein 70 complementary DNA (cDNA) of Laminaria japonica (designated as LJHsp70) was obtained by reverse transcriptase-polymerase chain reaction (RT-PCR) coupled with rapid amplification of cDNA ends. The full length of LJHsp70 cDNA was 2,918 bp, with a 5' untranslated region of 248 bp, a 3' untranslated region of 696 bp, and an open reading frame of 1,974 bp encoding a polypeptide of 657 amino acids with an estimated molecular mass of 72.03 kDa and an estimated isoelectric point of 4.97. There was highly repeated sequence of CAA in 5' untranslated region of LJHsp70. The result of phylogenetic tree of Hsp70s, the BLAST program, analysis and cytosolic Hsp70-specific motif of LJHsp70 verified that the cloned LJHsp70 belonged to cytosolic Hsp70 family. Three typical Hsp70 signature motifs were detected in LJHsp70 by InterPro analysis. Under different stress conditions, messenger RNA (mRNA) expression levels of LJHsp70 were quantified by quantitative RT-PCR. To L. japonica sporophytes kept in different temperatures for 1 h, the expression level of LJHsp70 at 30A degrees C was highest and twofold higher than that at 10A degrees C. To L. japonica sporophytes kept at 25A degrees C for different times, the mRNA expression level of LJHsp70 reached a maximum level after 7 h and then dropped progressively. The expression level of LJHsp70 at 0 or 5aEuro degrees salt concentration for 2 h was twofold higher than that at 30aEuro degrees salt concentration for 2 h. The results showed that LJHsp70 may be a kind of potential biomarker used to monitor environment conditions.