中国西沙群岛底栖甲藻热带库里亚藻(Coolia tropicalis)的形态学、系统发育及毒性研究     

黄丽芬  李群  吕颂辉  张亮  谢学东 《热带海洋学报》2020,39(3):86-97

库里亚藻(Coolia)是一类广泛分布且具有生物毒性的海洋底栖甲藻。本研究对近年来在中国南海西沙群岛海域采集分离的4株库里亚藻, 通过光镜及电镜下的形态学观察, 并结合基于核糖体大亚基(large subunit, LSU)rDNA(D1-D3)和内部转录间隔区(internal transcribed spacer, ITS)的序列进行系统发育分析, 鉴定该4个株系为热带库里亚藻(Coolia tropicalis)。在卤虫(Artemia salina)生物毒性试验中, 热带库里亚藻不同株系毒素提取液对卤虫幼虫表现出了毒性差异, XS554株系的48h半致死浓度(LC50)为1.42mg·mL ^-1(约相当于1.1×10 ⁵cells·mL ^-1), 5XS15株系的LC50为1.92mg·mL ^-1(约相当于1×10 ⁵cells·mL ^-1)。  相似文献   

Genetic connectivity among populations of two congeneric direct-developing whelks varies across spatial scales     

Angela M. Fleming  Melanie M. Dohner  Peter A. Ritchie 《新西兰海洋与淡水研究杂志》2018,52(1):100-117

We examined the phylogeographic structure of two congeneric, direct-developing, intertidal whelks endemic to New Zealand, Cominella virgata and C. maculosa. A total of 855 specimens were collected from 23 rocky shore locations and we used them to determine the level of DNA sequence variation at the mitochondrial DNA (mtDNA) cytochrome c oxidase subunit I gene. Cominella virgata and C. maculosa have relatively high levels of haplotype diversity but low levels of nucleotide diversity. Sample sites formed regional groups that were composed of genetically differentiated populations, a finding consistent with their limited dispersal abilities. Cominella virgata showed higher levels of regional differentiation than C. maculosa, and there were also species-specific differences in genetic patterns within some regions. Both species exhibited genetic homogenisation among proximate sites within groups, suggesting some dispersal does occur between areas that are not connected by contiguous rocky shore habitat.  相似文献   

Effect of carbon and nitrogen ratio control on Artemia growth,water quality,biofloc microbial diversity under high salinity and zero-water exchange culture condition     

WANG Shanyue  CUI Xueping  XU Ruyi  GAO Meirong  SUI Liying 《海洋湖沼学报（英文）》2019,(5):1768-1776

Biofloc technology has been applied successfully in the intensive aquaculture of several fish and shrimp species. The growth of heterotrophic microorganisms can be stimulated through adding extra carbon, which reduces the nitrogen level in the water and provides microbial protein to the animals. However, most of the studies and practical applications have been conducted in freshwater and marine environment. This paper focused on brine shrimp Artemia that lives in high salinity environment together with other halophilic or halotolerant microorganisms. The effect of carbon supplementation on Artemia growth, water quality, and microbial diversity of biofl ocs was studied in the closed culture condition without any water exchange. The salinity of the culture medium was 100. A 24-d culture trial was conducted through supplementing sucrose at carbon/nitrogen (C/N) ratio of 5, 15, and 30 (Su5, Su15, and Su30), respectively. The culture without adding sucrose was used as a control. Artemia was fed formulated feed at a feeding ration of 60% recommended feeding level. The results showed that sucrose supplementation at higher C/N ratio (15 and 30) signifi cantly improved the Artemia survival, growth and water quality ( P <0.05). Addition of sucrose at C/N ratio of 15 and 30 significantly increased biofloc volume (BFV)( P <0.05). The Illumina MiSeq sequencing analysis showed that supplementing carbon at C/N ratio of 15 had a better total bacterial diversity and richness, and shaped the microbial composition at genera level. This study should provide information for studying the mechanism of biofloc technology and its application in high salinity culture conditions.  相似文献   

卤虾油醇解工艺的正交试验研究和GC-MS分析     

周冉  韩振为  陈绍忠 《海洋通报》2006,25(6):69-75

采用正交试验法对卤虾油醇解反应条件进行了研究。结果显示:当乙醇钠催化剂为0.5%(卤虾油重),反应温度60℃,反应时间3h,乙醇/卤虾油(质量比)=40%的条件下,卤虾油的醇解率可达98.04%;按对结果的影响大小依次排列如下:催化剂用量、反应温度、反应时间、醇油比。用GC-MS技术对其有效成份进行了分析,从中鉴定出30多种成分,主要为丁内酯、7-亚丙基二环[4.1.0]庚烷、二甲基癸烷、十一酸、棕榈酸、油酸、硬脂酸、EPA、亚麻酸、亚油酸等。  相似文献   

中国卤虫(Artemia sinica)早期胚胎发育相关基因表达序列标签(ESTs)分析     

侯林  邹向阳  姚锋  林盛国  徐明玉  陈志娟  姜丽娟  孙文静 《海洋与湖沼》2008,39(2):139-144

以mRNA差异显示技术分析了中国两性生殖卤虫早期胚胎发育相关基因的表达序列标签(ESTs),共回收了2000条差异条带并进行了克隆、测序,在GenBank/DDBJ/EMBL数据库中用BLASTX和BLASTN软件分别与NCBI上的非冗余核酸序列数据库进行同源性比对,得到分值较高、长度在100bp—2kb以内的ESTs序列133条。所发现的133条ESTs的生物学功能分类为:能量代谢占24%、细胞生长、分裂相关基因占23%、RNA相关占17%、体节形成占12%、蛋白质合成占3%、转录因子占3%、离子转运占5%、细胞信号转导占4%、未知占9%。对所发现的ESTs进行了RT-PCR测定,排除假阳性能够提供足够数量的信息用于获取其全长cDNA,进而获得其全长基因序列以用于功能研究。另外,研究发现了包括小热休克蛋白基因家族、Hox基因家族的abdA和Dfd基因、A-trh基因(排盐器官及盐调节基因)、HIF(缺氧诱导因子)、CK-M2(肌肉型磷酸激酶基因)和GRP基因(富甘氨酸蛋白基因)等20个具有明显功能的相关基因的ESTs和完整基因序列和开放阅读框(ORF)。经初步推断这些ESTs和基因的功能大多为与卤虫发育的生理、生化相关的基因有关。所研究的133条ESTs基本代表了卤虫早期胚胎发育相关功能基因的表达谱。  相似文献   

Intercellular localization of nitrogenase in a non-heterocystous cyanobacterium (cyanophyte), <Emphasis Type="Italic">Trichodesmium</Emphasis> sp. NIBB1067     

Kaori Ohki 《Journal of Oceanography》2008,64(2):211-216

The nitrogenase activities of cyanobacteria of the genus Trichodesmium are strictly light-dependent, although they do not develop heterocysts. Recently, the development of heterocyst-equivalent cells (diazocytes) was suggested in Trichodesmium spp. However, no cells with a similar appearance to diazocytes could be found in Trichodesmium sp. NIBB1067. An immunocytochemical analysis of nitrogenase in individual cells was performed using polyclonal antibodies generated from DNA fragments of genes encoding the Fe-protein and the α-and the β-subunit of the MoFe-protein of nitrogenase of Trichodesmium sp. NIBB1067. Visualization of the antibody binding was carried out using a horseradish peroxidase-conjugated secondary antibody and a chromogenic substrate, 3,3′-diaminobenzidine, to avoid the masking effects caused by the bright autofluorescence emitted by Trichodesmium cells. Nitrogenase proteins were detected in almost all the cells (always higher than 95% of total cells) grown under nitrogen-limited conditions. These results indicate that Trichodesmium sp. NIBB1067 does not differentiate heterocyst-equivalent cells.  相似文献   

网箱养殖石斑鱼病毒性神经坏死病流行调查   总被引：1，自引：0，他引：1  

苏亚玲 《海洋科学》2008,32(9):52-56

厦门海水网箱养殖石斑鱼春、夏季节暴发性疾病经过流行病学调查和病原检测,确认主要病原为病毒性神经坏死病毒,病鱼外观表现典型的神经异常症状。应用逆转录聚合酶链式反应（RT—PCR）技术检测5种石斑鱼：赤点石斑鱼（Epinephelus akaara）、青石斑鱼（E．awoara）、云纹石斑鱼（Emoara）、紫石斑鱼（E．lanceolatus）、马拉巴石斑鱼（E．malabaricus）.检测76条石斑鱼,检出率90％;病鱼的脑、视网膜、肾脏、肝脏、脾脏等组织均能检出神经坏死病毒（NNV）,以脑和视网膜检出率最高,肾脏次之,肝脏、脾脏检出率较少,鳃未检出。  相似文献   

火腿许水蚤对牙鲆仔稚鱼成活、生长及脂肪酸组成的影响   总被引：1，自引：0，他引：1  

刘光兴  徐东晖  邱旭春  黄瑛  崔建丽  朱丽岩 《中国海洋大学学报(自然科学版)》2007,37(2):259-265

在分析火腿许水蚤、卤虫无节幼体及轮虫这3种饵料生物脂肪酸组成的基础上,研究它们对牙鲆仔稚鱼存活、生长及脂肪酸组成的影响。结果表明:火腿许水蚤体内3种高度不饱和脂肪酸(ARA,EPA,DHA)总量为34.18%,明显高于其它2种动物的含量(卤虫无节幼体4.67%;小球藻强化轮虫9.39%)。投喂火腿许水蚤的仔鱼成活率极显著高于投喂卤虫无节幼体的仔鱼,与投喂混合饵料(卤虫无节幼体和火腿许水蚤按比例混合)的仔鱼存活率差异较显著;其全长增长倍数和增重倍数极显著高于投喂卤虫无节幼体和混合饵料的仔鱼。投喂火腿许水蚤的稚鱼成活率显著高于投喂卤虫无节幼体的稚鱼,与投喂混合饵料的稚鱼存活率差异不显著;其全长增长倍数和增重倍数极显著高于投喂卤虫无节幼体和混合饵料的稚鱼。投火腿许水蚤的仔稚鱼体内ARA、EPA、DHA的含量明显高于投喂混合饵料的和投喂卤虫无节幼体的仔稚鱼。  相似文献   

Piwi基因参与两性卤虫(Artemia franciscana)的生殖调控研究     

任翊卓  韩学凯  左佳俊  欧阳雪梅  段虎  隋丽英 《海洋与湖沼》2021,52(6):1567-1576

Piwi（P-element induced wimpy testis）基因编码Piwi蛋白,在生殖干细胞的自我更新、减数分裂过程、RNA沉默和转录调控中起重要作用。为探究Piwi基因参与两性卤虫生殖发育的作用,从两性卤虫Artemia franciscana转录组中筛选获得Piwi基因开放阅读框,进行序列分析和结构域预测等生物信息学分析,采用qPCR技术研究该基因在A.franciscana生殖腺发育不同时期表达特征,并利用RNAi显微注射技术探究其功能。生物信息学分析表明,A.franciscana Piwi基因的开放阅读框长2 619 bp,编码872个氨基酸;Piwi基因编码的蛋白分子量为98.11 kDa,等电点为9.50,为碱性亲水性蛋白,无信号肽和跨膜结构;存在Piwi和PAZ结构域及ArgoL1结构域,二级结构以α-螺旋为主,三级结构与之对应;系统进化树显示A.franciscana与蚤状溞和大型溞的Piwi序列相似性最高。qPCR结果表明,Piwi基因在卵巢的卵黄发生晚期和晚期胚胎表达量最高,显著高于卵黄发生早期和早期胚胎（P<0.01）;Piwi基因在精巢的未成熟期表达量最高,显著高于成熟早期、成熟中期和成熟晚期（P<0.01）。RNAi结果显示,该方法能显著降低Piwi基因的表达水平（P<0.01）,并导致A.franciscana所产后代均为休眠卵,说明Piwi基因不但在A.franciscana生殖发育调控起重要作用,而且可能在其繁殖方式决定过程中起关键作用。研究结果为两性卤虫Piwi/piRNA功能和分子机制调控的研究提供了基础信息,将有助于揭示Piwi基因参与调控两性卤虫生殖发育机制。  相似文献   

Tidal flow near Mana Island,Cook Strait,New Zealand     

E. Bradford  R. A. Wooding 《新西兰海洋与淡水研究杂志》2013,47(1):31-42

Numerical calculations carried out for tidal flow on a small region of the New Zealand coast near Mana Island (41° 5 S, 174° 47 E) solved a finite difference form of the tidal equations, and assumed that the velocity boundary conditions could be approximated by a modified Kelvin wave formula. The results were exponentially smoothed in time at each step in the calculation to remove spurious modes.

The main results are shown as plots of tidal velocity vectors around Mana Island at equally spaced time intervals over a tidal cycle for one run commencing at low tide. The flow becomes very complex, with eddy shedding occurring in the wake of Mana Island, and a tidal rip developing across the shallow connection between Mana Island and the mainland.  相似文献