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1.
为研究不同盐度对文蛤呼吸代谢的影响,本实验设置5个盐度(‰)梯度(11、18、25、32、39),检测不同盐度对文蛤(Meretrixmeretrix)耗氧和排氨的影响,以及文蛤的外套膜、鳃、肝胰腺三种组织中乳酸脱氢酶和Na+/K+-ATP酶活性的变化。结果表明:随着盐度的不断升高,文蛤耗氧率先升后降再升,在盐度18时达到最大值;排氨率先升后降,在盐度32时达到最大值。随着盐度不断升高和胁迫时间延长,文蛤的肝胰腺中乳酸脱氢酶活力总体呈先升高后下降再升高的趋势(P0.05),酶活力在盐度39时为最高;随着盐度不断升高和胁迫时间延长,文蛤的外套膜中Na+/K+-ATP酶活力总体呈先下降再升高后下降的趋势(P0.05),在盐度32时为最高;文蛤的外套膜和鳃中乳酸脱氢酶活力以及鳃和肝胰腺中Na+/K+-ATP酶活力受盐度影响不显著(P0.05),酶活力变化也多呈现"W"形的变化趋势。研究结果为文蛤的人工养殖提供参考。 相似文献
2.
Glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) is the first and main regulated enzyme of oxidative pentose phosphate pathway (OPPP), catalyzing the conversion of glucose-6-phosphate to 6-phospho-gluconolactone and playing important roles in the growth and development of plants. It is preciously reported that the enhancement of freezing resistance of Populus suaveolens cuttings is clear related to the distinct increase in cytosolic G6PDH activity. Here, a 1697 bp cDNA fragment (PsG6PDH) is amplified by RT-PCR from cold-induced total RNA of the freezing-tolerant P. suaveolens . A sequence analysis showed that PsG6PDH coding region had 1 530 bp and encoded 510 predicted amino acid residues. Genomic Southern analysis revealed that the isoform is encoded by a few copies of the gene in the poplar genome. The cloned gene PsG6PDH is cloned into binary vector pBI121 and used to transform tobacco. PCR and Southern blotting results verified integration of this gene into the genome of tobacco. Moreover, cold treatment experiments and membrane defense enzyme activity analysis confirmed that overexpression of the PsG6PDH gene could enhance the tolerance to cold or frigid stresses in transgenic plants. 相似文献
3.
REN Xueying SUI Zhenghong ZHANG Xuecheng 《中国海洋大学学报(英文版)》2006,5(2):146-150
Glyceraldehyde-3-phosphate dehydrogenase （GAPDH） plays important roles in various cellular processes. A cytosolic GAPDH encoding gene （gpd） of Gracilaria/Gracilariopsis lemaneiformis was cloned and characterized. Deduced amino acid sequence of the enzyme of G. lemaneiformis had high homology with those of seven red algae. The 5＇-untranslated regions of the GAPDHs encoding genes of these red algae varied greatly. GAPDHs of these red algae shared the highly conserved glyceraldehyde 3-phosphate dehydrogenase active site ASCTTNCL. However, such active site of Cyanidium caldarium was different from those of the other six algae at the last two residues （CL to LF）, thus the spatial structure of its GAPDH active center may be different from those of the other six. Phylogenetic analysis indicated that GAPDH of G. lemaneiformis might have undergone an evolution similar to those of Porphyra yezoensis, Chondrus crispus, and Gracilaria verrucosa. C. caldarium had a closer evolutionary relationship with Cyanidioschyzon merolae than with Cyanidium sp. Virtual Northern blot analysis revealed that gpd of G. lemaneiformis expressed constitutively, which suggested that it might be house-keeping and could be adapted as an inner control in gene expression analysis of G. lemaneiformis. 相似文献
4.
Three continuous marine fish cell lines of FG (i. e., Hounder Gill) from flounder (Paralichthys olivaceus) gill, SPH (i. e. , Sea Perch Heart) from sea perch (Lateolabrax japonicus) heart and RSBF (i.e., Red Sea Bream Fin) from red sea bream (Pagrosomus major) fin, were characterized by lactate dehydrogenase (LDH) isozyme and morphological analysis. The LDH isozyme patterns of these three cell lines and their corresponding tissues of origin were investigated and compared. The results showed: (1) No difference was found in the LDH isozyme patterns of FG and flounder gill tissue. However, the LDH isozyme patterns of SPH and RSBF were significantly different from their corresponding tissues of origin; (2) LDH isozyme patterns of FG, SPH and RSBF were markedly different from each other and could serve as genetic markers for species identification and detection of cross contamination. Morphological change analysis of these three cell lines in comparison to their original tissues indicated that FG cells still appeared epithelioid without morphological transformation. However, morphological changes were found in SPH and RSBF compared to their original tissues. Therefore, the cellular morphology was still plastic in the relatively stable culture conditions, and it was possible that change of LDH patterns wasrelated to morphological changes of fish cells in vitro. 相似文献
5.
Response of microbial community to petroleum stress and phosphate dosage in sediments of Jiaozhou Bay,China 总被引：1，自引：0，他引：1
ZHAO Yangguo CHEN Min BAI Jie LI Xinwei Farhana Zulfiqar and WANG Qianli 《中国海洋大学学报(英文版)》2014,13(2):249-256
The dynamic microcosms were used to evaluate the effect of oil spills on microbial ecological system in marine sediment and the enhancement of nutrient on the oil removal. The function and structure of microbial community caused by the oil pollution and phosphate dosage were simultaneously monitored by dehydrogenase activity assay and PCR-denaturing gradient gel electrophoresis (DGGE) techniques. The results indicated that the amount of total bacteria in all dynamic microcosms declined rapidly with incubation time. The number of petroleum-degrading bacteria and the activity of sediment dehydrogenase were gradually enhanced by petroleum in the oil-treated microcosms, while they both showed no obvious response to phosphate dosage. In comparison, phosphate spiked heterotrophic bacteria and they showed a significant increase in amount. DGGE profiles indicated that petroleum dosage greatly changed community structure, and the bacteria belonged to class Deltaproteobacteria, and phyla Bacteroidetes and Chlorobi were enriched. This study demonstrated that petroleum input greatly impacted the microbial community structure and consequently the marine sediment petroleum-degrading activity was enhanced. Phosphate dosage would multiply heterotrophic bacteria but not significantly enhance the petroleum degradation. 相似文献
6.
《Limnologica》2016
The Ponto–Caspian amphipod Pontogammarus robustoides was introduced into Lithuanian inland waters more than 50 years ago and is now among the most successful local crustacean invaders. Existing as an oxyphilic species in its native range, in Lithuania it managed to establish in some lentic eutrophic waters facing long-term hypoxic conditions under winter ice cover, or shorter periods of hypoxia during the warm season. Recently, it has been observed to be further expanding in such waters. The aim of this study was to explore the possible divergence in anaerobic metabolism among introduced populations facing different selective pressures. A closed-bottle experiment was conducted using individuals from three Lithuanian lentic water bodies of different trophic status: mesotrophic, eutrophic and hypertrophic. Severe hypoxia was gradually reached, after which lactate dehydrogenase activity was significantly higher in amphipods from eutrophic and hypertrophic, than from mesotrophic environments, and was well correlated with trophic status of inhabited environments as assessed by chlorophyll a concentration. These findings suggest a physiological acclimation response to oxygen deficiency faced by the species in some environments in the northern invaded range, which may have a genetic background. Such resistance to oxygen deficiency may expand the environmental niche and promote species’ spread into previously unsuitable habitats, which may pose a threat to native species residing in refuges that are currently free of the invader. 相似文献
7.
采用高pH不连续系统聚丙烯酰胺垂直板凝胶电泳,特异性组织化学染色对中华绒螯蟹(Eriocheir sinensis)的血清、肌肉、鳃、心脏、肝胰腺、精巢和精子等组织的乳酸脱氢酶(LDH)同工酶酶谱进行了研究。同时,利用2种底物(乳酸钠和α-羟基丁酸钠)进行了特异性反应,并对其精子特异性乳酸脱氢酶进行了研究。结果表明:以乳酸钠为底物时,中华绒螯蟹的肌肉、鳃、血清和心脏有2条谱带,而精巢和精子有3条谱带,但在肝胰腺中未发现谱带;以α-羟基丁酸钠为底物时,只在血清、精巢和精子发现有1条谱带。从而说明,中华绒螯蟹乳酸脱氢酶同工酶存在组织特异性;精子存在特异性乳酸脱氢酶。 相似文献
8.
从刺激隐核虫(Cryptocaryon irritans)滋养体/包囊前体c DNA文库中筛选出了甘油醛-3-磷酸脱氢酶基因(Ci GAPDH),定点诱变Ci GAPDH基因开放阅读框内的非通用密码子后,构建其原核表达载体p GEX-4T-3/Ci GAPDH,转化到大肠杆菌BL21(DE3)中,用异丙基硫式-B-D-半乳糖苷诱导表达,结果大肠杆菌成功表达了r Ci GAPDH蛋白。用抗r Ci GAPDH蛋白的鼠血清进行免疫印迹分析,结果抗血清能够识别刺激隐核虫各期虫体的天然Ci GAPDH蛋白,其表观分子质量为37.3 ku,与根据氨基酸序列推算的理论值相符;实验表明r Ci GAPDH蛋白具有很好的免疫原性,而且Ci GAPDH在生活史的各阶段均有表达,符合持家基因的特征。利用间接免疫荧光抗体实验(IFAT)检测天然Ci GAPDH蛋白在刺激隐核虫幼虫上的定位,结果表明天然Ci GAPDH蛋白主要分布在幼虫的细胞质内,且在胞口位置分布最多。对Ci GAPDH的进一步研究可能为刺激隐核虫感染的药物靶点的寻找多条线索。 相似文献
9.
土壤残油生物降解性与微生物活性 总被引：12，自引：0，他引：12
利用色谱－质谱联机（GC／MS）、柱层析分析方法、浊度法和微生物脱氢酶法，确定土壤残油污染物的构成、油污土壤优势降解菌、残油降解过程中微生物活性及其动态变化。研究结果表明，长期残留在淄河滩土层中的石油 烃类主要由沥表肝质、胶质构成，占总烃类的60％－80％，经过90d生物降解试验，残油降解率仅为20％，污染土层中的主要优势菌为球菌和杆菌，菌群鉴定为黄假单胞菌（Xanthonmonas)、芽孢杆菌（Bacillus )等。据微生物脱氢酶动态变化的初步研究结果，微生物脱氢酶活性变化可作为衡量微生物活性变化的 重要指标。 相似文献
10.
Black‐foot abalone, Haliotis iris, were sampled from two populations in warm northern waters, and from two in colder southern waters. Abalone muscle is characterised by high activity of the glycolytic pyruvate reductase enzyme, tauropine dehydrogenase (TDH). Adductor muscle TDH was profiled for thermostability and activity to test the hypothesis that the enzyme may show adaptation in titre or kinetic characteristics reflecting thermal habitat. Temperature dependency of the apparent Michaelis‐Menten constant of TDH for pyruvate (appKmpyr) suggested eurythermal enzyme behaviour below 20°C, and compromised function at the higher temperatures of northern populations occurring in the summer months. Thermostability profiles and enzyme activities suggest TDH expression does not differ significantly among populations (P > 0.05), indicating that this locus shows no compensation for temperature. The optimal temperature for efficient TDH function, estimated from Vmax./appKmpyr, is close to 20°C. The possible thermal constraints on glycolytic metabolism in H. iris are discussed. 相似文献