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The molecular distribution of dissolved proteins in seawater from coastal marine environments in Uranouchi Bay, Kochi Prefecture, is first reported in this article. Occurrence of bacteria-derived dissolved proteins and their source bacteria were examined using a probe of the antibody (anti-Omp35La) against a porin outer membrane protein (Omp35La) of the fish pathogenic bacterium Vibrio (Listonella) anguillarum. The electrophoretograms of dissolved proteins from coastal seawater showed a large number of discrete and individual proteins overlapped each other over a wide range of molecular masses indicating active processes in coastal environments in transferring proteins from organisms to the inanimate dissolved protein pool. Among the dissolved proteins, 37 kDa- and 18 kDa-proteins reacted with the Omp35La. In order to isolate the source bacteria of such dissolved proteins, bacteria from seawater and diseased fish were screened by colony Western blotting with anti-Omp35La. The reactive strains were further examined in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)/Western blotting to verify the presence of Omp35La homologues among the outer membrane proteins of such strains. Outer membrane proteins reacting with anti-Omp35La were detected in only 4 strains of the 129 strains that were positive in the colony Western blotting. The level of possible source bacteria of 37 kDa- and 18 kDa-dissolved proteins was suggested to be 5–6 orders of magnitude lower than the total bacterial count. The present study leads us to hypothesize that a minor portion of the bacterial assemblage is responsible for the dissolved proteins in the coastal waters. 相似文献
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Ding Meili 《海洋学报(英文版)》1992,11(1):123-130
-The rot disease of Laminaria occurs often in nurseries of sporeling and commercial cultivation in the sea and results in economic loss greatly. Usually the disease outbreaks accompanied with massive multiplication of alginic acid decomposing bacteria. From the section of the decaying Lamuutria which resulted from the inoculation of alginic acid decomposing bacteria, it was observed that the bacteria invaded the epiderm of the Laminaria surface at first, then entered the ex-odermis, endodermis and pith. In addition, there were a great amount of bacteria in the intercellular region and a lot of free cells of the algae in the decaying areas. The wall of some free cells was decomposed, which led to soft tissue or disintegration. Alginic acid decomposing bacteria are normal epiphytic microorganisms growing on Lamuutria surface. These bacteria do not cause disease at normal environmental conditions. The experiments showed that the unfavourable conditions, e. g. , wounding, overcrowding, high temperature redu 相似文献
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CHI Shan QIAN Hao LI Tianyong WANG Xumin LIU Cui REN Lei TANG Xuexi LIU Tao 《海洋学报(英文版)》2014,33(9):139-151
In the past two decades, many studies have focused on the classification within genus Laminaria, ultimately trying to divide it into two subgroups or genera: Laminaria and Saccharina. A significant debate still surrounds the question of its division, as the conflicting phylogenetic hypotheses that have resulted from the classification studies are based on different taxon sampling, molecular markers, or analysis methods. It is aimed at elucidate the molecular phylogeny within Laminaria and Saccharina. The nine species of Laminariales are sampled from northern Asia and Europe, and 23 new sequences in the nuclear, plastid, and mitochondrial genomes are determined to identify their taxonomic status. The phylogenetic analyses of 71 species are performed, including representatives from six of the seven families of the order Laminariales, based on three separate data sets. An evidence is provided to strongly support a clear split that maintains the two recognized genera, Laminaria and Saccharina, with Laminaria appearing to be the ancestor group. Further, analyses indicate that all taxa in Saccharina and Laminaria did not form a monophyletic lineage, instead Laminariaceae and Lessoniaceae grouped together interlacedly, and Costariaceae appeared as the sister taxon of the Lessoniaceae–Laminariaceae clade. In the phylogenetic analysis, mitochondrial c oxidase I(COI) sequences appeared to be the most credible molecular marker which was more befitting than nuclear encoded internal transcribed spacer(ITS) and plastid encoded rbcL for establishment of Laminariales systematics. It is the most comprehensive phylogeny of the order Laminariales, and contributes to an enhanced understanding and estimation of the phylogenetic relationships for the economically important seaweeds, Laminaria and Saccharina. 相似文献
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基于浒苔暴发海水池塘的微生物生态特征研究 总被引：3，自引：1，他引：2
为研究浒苔对海水养殖环境微生物生态的影响,采用Illumia高通量测序技术测定冬季垦区进水区、浒苔暴发的池塘和排水区水体以及底泥中菌群结构,分析进水区、池塘养殖区和排水区的环境微生物结构演变过程。结果表明:（1）γ-变形细菌、α-变形细菌、放线菌、拟杆菌和δ-变形细菌为海水养殖区的优势细菌门类;（2）进水区水体和底泥微生物种类和多样性指数均高于浒苔池塘和排水区;浒苔暴发的池塘和排水区微生物群落结构较为相似;（3）浒苔池塘的水体微生物以异养细菌为主,底泥以脱硫杆菌等厌氧细菌为主,增加了底泥潜在产生硫化氢的危害;（4）进水区水体含有丰度较高的弧菌和鱼立克次氏体等条件致病性病原菌,而浒苔池塘中含量较低,说明浒苔对弧菌等有一定的抑制作用;但浒苔暴发的池塘和排水区中另一种潜在致病菌黄杆菌类的丰度较高,养殖品种务必防患此类病菌感染疾病的发生。本文从微生态学角度全面揭示浒苔对近岸海区、海水池塘和排水区微生态演变过程的影响,发现了浒苔具有抑制和增加不同致病菌的双重作用,这对水产养殖有一定指导,也为浒苔发生原因、预报、预防等研究提供一定理论参考。 相似文献
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The distribution of Cystoseira species was studied at 103 coves in the island of Menorca (Balearic Islands, NW Mediterranean). Both geomorphological parameters and anthropogenic pressures were considered in order to investigate which were the main environmental factors explaining their distribution. Several factors contributed to explain the composition of Cystoseira assemblages in the sampled coves being coastal morphology, bottom nature, nutrient concentration in seawater and urbanization level of the coast the most important. The relatively high number of Cystoseira species found in Menorca suggested a general high quality of the environment. However, in southern coves the number and abundance of Cystoseira spp. was reduced compared to the northern ones. This pattern seems to be related both to a higher anthropogenic pressure and to a less favourable geomorphology at southern coves. When strong anthropogenic disturbances were present (proximity to harbour areas), coves were completely devoid of Cystoseira specimens. As historical data is available for some of these sites, we can document the disappearance of some Cystoseira species at these coves, which seems to be related to increased pollution levels. However, as the absence of Cystoseira assemblages can also respond to a lack of a suitable geomorphology, their use as bioindicators of water quality needs of a definition of proper reference sites. 相似文献
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河流弧菌(Vibrio fluvialis)对大黄鱼( Pseudosciaena crocea ) 鳃粘液粘附特性研究 总被引：1，自引：0，他引：1
采用间接ELISA法(最低检测值约104cfu)研究不同培养条件、不同培养阶段、抗体处理、营养饥饿等对河流弧菌粘附作用的影响。结果表明,经TSB培养的菌体的粘附作用极显著强于TSA培养的菌体的粘附作用(P<0.01);河流弧菌能很好地粘附于大黄鱼粘液,粘附量随菌浓度升高而增大并符合饱和粘附动力学:y=0.1782ln(x)1.6923(R2=0.9810);不同生长阶段河流弧菌的粘附能力不同,在培养初期阶段细菌的粘附量先是随着培养时间的延长而增大,并在培养24h后粘附量达到最大,而后随着培养时间的延长其粘附量急剧下降;抗体处理后河流弧菌的粘附量显著低于对照组(P<0.05);营养饥饿菌体的粘附量明显降低。以上结果表明:海水中的河流弧菌能很好地粘附于大黄鱼鳃粘液,其粘附作用受细菌培养条件、营养状况等自身因素的显著影响。本研究结果有助于了解河流弧菌的流行病学和致病机理。 相似文献
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Kazunari Ogawa 《Journal of Oceanography》1974,30(2):54-60
Some experiments were carried out to explain thein situ phenomena that the number of coliform organisms decreased rapidly from estuaries to offshore, and also at deeper layer, and that the appearance of coliform types varied.In natural seawater, experimental results did not show thatEscherichia coli was extinct by self-purification or anti-biosis action of seawater, but it showed that this organism decreased mainly because of their starvation caused by lack of nourishment. Although the decreasing rate of bacterial density was delayed in enriched seawater, addition of nutrient even at the time of bacterial extinction promoted the appearance of variated form of this bacteria with floc formation.Flocculation of bacterial cells was influenced by quality and quantity of added nutrients. Temperature was shown to have an effect on the floc formation, but appearance of variated form in flocculated cells ofE. coli was not affected by temperature. Flocculated particles of coliform bacteria were adsorbed on suspended particles in seawater and precipitated rapidly. This phenomenon seems to be a cause of the rapid disappearance of coliform bacteria in coastal waters.In bottom deposits the coliform bacteria probably survive longer as physiologically variated forms when suitable nutrients were supplied. 相似文献
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好氧不产氧光合(AAP)细菌因其具有利用溶解性有机物及光能的能力,在海洋碳循环及能量流动中发挥着重要的作用。该类细菌广泛分布在海洋环境中,其在不同生境中的多样性已被调查。但到目前为止,人们对于高纬度地区好氧不产氧光合细菌的认识还较为缺乏。有鉴于此,本研究基于编码光反应复合物上一个色素结合蛋白亚基的pufM基因,对北极王湾及南极乔治王岛近岸水体中夏季好氧不产氧光合细菌的多样性进行了检测。针对2个王湾站位和2个南极麦克斯维尔湾站位构建了4个pufM基因克隆文库,获得674个阳性克隆子。北极克隆子全部由α-变形细菌组成,而南极克隆子则包括α-变形细菌及β-变形细菌。来源于类似红细菌科的pufM基因在所有样品中皆占据优势。此外,与一株滴状亚硫酸盐杆菌中质粒编码的pufM基因存在亲缘关系的序列,在南、北极样品中均占优势。结果表明海洋环境中的pufM基因存在跨极甚至是环球分布。与此同时,南、北极序列之间的差异,也表明了极地地方种的存在。这些结果显示,作为好氧不产氧光合细菌的红细菌科在两极的近岸水体中具有重要的地位。 相似文献
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Kuninao Tada Koji Monaka Masakazu Morishita Toshiya Hashimoto 《Journal of Oceanography》1998,54(4):285-295
Standing stocks and production rates of phytoplankton and abundance of bacteria were investigated at 39 stations in the Seto
Inland Sea, Japan during four crulses in October 1993, January, April and June 1994. Primary productivity was measured by
the13C tracer method. Photosynthetic rate varied from 0.41 to 32.1 μgC/1/h with an average value of 4.67 μgC/l/h. Annual primary
production was estimated to be 218 gC/m2/year. Annual primary production in this study was 1.8 times as high as the values which were previously reported at same
area. The reason for the disagreement between our primary production value and previous values is not thought to be due to
the difference of methods used for measuring primary production or the different Chl.a concentrations but to the method of estimating the primary production in the euphotic zone from thein vitro measurements. The distribution of bacterial cells in surface seawater was examined during the same cruises. Bacterial cell
density ranged from 0.32 to 3.4×106 cells/ml. The density was relatively high in the eutrophic regions of Hiroshima Bay and Osaka Bay In addition, a high density
of bacteria was also observed in an area within Suo Nada where Chl.a was relatively low. The disparity between Chla and bacterial density in Suo Nada suggests that bacterial abundance can be controlled by the availability of substrates other
than phytoplankton exudate. 相似文献