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1.
为探究海假交替单胞菌pilZ基因的缺失对生物被膜形成及突变菌生物被膜对厚壳贻贝幼虫附着变态的影响,本文通过同源重组构建pilZ基因缺失菌,分析了基因缺失菌生物被膜的细菌密度、膜厚、c-di-GMP水平和胞外产物含量等特性的变化及其对厚壳贻贝幼虫附着变态的调控作用.结果表明:与野生型菌株相比,pilZ基因缺失菌形成的生物...  相似文献   

2.
The epibiotic communities (diatoms and metazoans) on the outer surfaces of the shell of the barnacle Balanus amphitrite (BSh) and its opercular valves (the scutum and tergum; BST) were investigated on a monthly basis for 1 year in a tropical monsoon‐influenced estuary and compared with that of the surrounding rock biofilm. BSh and BST were rich in the diatoms Achnanthes longipes and Melosira nummuloides and amongst the invertebrates, nematodes and tardigrades were abundant. To the best of our knowledge, this is the first report of epibiosis on the acorn barnacle. Diatom abundance was at its maximum during the monsoon season on all the inter‐tidal substrata i.e. BSh, BST and rock. A significant correlation was found between the density of diatoms and invertebrates associated with the BSh and BST, possibly because of the trophic relationship between them or the suitability of the physical environment. The possible role of these epibionts on the settlement of this barnacle species is currently unknown and needs further investigation.  相似文献   

3.
Marine mollusks provide shelter to epibiotic organisms which settle on the outer surface of their hard shells. Epibionts can exert beneficial or detrimental effects on the host mollusk. In this study, the ecology of the association of the commercially valuable marine mobile scallop Patinopecten (=Mizuhopecten) yessoensis with its epibiotic barnacle Balanus rostratus was investigated. Fatty acid analysis was performed to determine the trophic relationships between these species. The distribution of fatty acid markers in this scallop species suggests an important contribution of diatoms, flagellates and animal material in its diet. The fatty acid analysis indicated a predominance of diatoms in the diet of the adult barnacles and some detrital input into the diets of young individuals. It was found that adult barnacles may compete with the scallops for food sources such as diatoms and zooplankton. It was revealed that with a negligible biomass of epibionts, the interactions between the barnacle and scallop may be regarded as commensalisms. An increase in the weight of epibiotic barnacles resulted in decreases in the weights and shell heights of the scallops, testifying to the adverse influence of a high biomass of epibionts on their host.  相似文献   

4.
中国对虾血淋巴抗菌活力的测定   总被引:3,自引:0,他引:3  
采用溶藻胶弧菌(Vibrio alginolyticus)、副溶血弧菌(V. parahaem olyticus)、哈维氏弧菌(V.harveyi)、嗜水气单胞菌(Aerom onashydrophila)对中国对虾(Penaeus chinensis)血浆样品、血细胞溶解物(HLS)样品的抗菌活力进行了测定。表明中国对虾血浆样品对四种细菌均表现出一定的抗菌活力。其中,三种弧菌活细胞数在孵育1h 时呈现最低;嗜水气单胞菌活细胞数在孵育4h 时最少。在三种弧菌中,血浆样品对哈维氏弧菌表现出的抗菌活力最强,而对副溶血弧菌表现出的抗菌活力最弱。血细胞溶解物样品对三种弧菌几乎没有表现出抗菌活力;嗜水气单胞菌在与血细胞溶解物样品孵育2h 时,其活细胞数呈现最低,说明血细胞溶解物样品对该菌表现出了一定的抗菌活力。由此显示,抗菌活力在中国对虾血浆样品中表现得较强,而在血细胞溶解物样品中表现得较弱,血淋巴抗菌因子可以在短时间内对细菌表现出其最强的活力,但对不同种细菌其抗菌作用强弱不同。  相似文献   

5.
Although a total ban on the use of TBT coatings is not expected in the short term, there is a growing need for environmentally safe antifouling systems. A search for new non-toxic antifoulants has been carried out among marine macroalgae. Antifouling activity of aqueous, ethanolic and dichloromethane extracts from 30 marine algae from Brittany coast (France) was examined in vitro against 35 isolates of marine bacteria. About 20% of the extracts were found to be active. The high levels of inhibitory activities against bacteria recorded in some extracts and the absence of toxicity on the development of oyster and sea urchin larvae and to mouse fibroblast growth suggests a potential for novel active ingredients in antifouling preparations.  相似文献   

6.
采用改良微孔板法建立哈维氏弧菌Vibrio harveyi TS-628菌株生物被膜体外模型,并进一步研究环境因子对哈维氏弧菌体外形成生物被膜的影响。结果发现,哈维氏弧菌TS-628菌株可以在聚苯乙烯板中形成生物被膜,并且该菌生物被膜的形成受起始菌液浓度、温度、pH等理化因子的显著影响。温度为30℃、NaCl质量分数为3%—6%、pH为7、孵育时间为36h是哈维氏弧菌形成生物被膜的最佳条件。此外哈维氏弧菌在分别经表皮黏液、鳃黏液、肠道黏液、肝脏提取液、脾脏提取液、肌肉提取液包被的基质上成膜效果显著,其中在经肝脏提取液包被的基质上形成的生物被膜量显著高于在其他生物基质上形成的生物被膜量(p<0.01)。  相似文献   

7.
马士德 《海洋科学》1983,7(5):25-27
藤壶对海洋设施危害极大。人们早在一百多年前就开始研究它,前人的研究偏重于藤壶的附着机制,而对其附着对金属腐蚀的影响研究甚少。作者研究了藤壶生长过程对普碳钢、蒙乃尔、工业纯钛和一种不锈钢(1Cr18Ni9Ti)等四种金属材料腐蚀的影响。  相似文献   

8.
为研究肠道细菌在厚壳贻贝(Mytilus coruscus)幼虫和稚贝生长发育过程中的作用,本研究从成体厚壳贻贝肠道中分离出了10株细菌,通过分别形成单一细菌生物被膜,检验其对厚壳贻贝幼虫和稚贝附着的影响和生物被膜特性。实验结果发现,10株肠道细菌所形成的生物被膜均能诱导厚壳贻贝幼虫和稚贝的附着,但不同种类肠道细菌的诱导能力不同,其中Bacillus sp.4对厚壳贻贝幼虫具有高诱导活性,Phaeobacter sp.1具有低诱导活性;Phaeobacter sp.1对厚壳贻贝稚贝具有高诱导活性,Bacillus sp.4具有低诱导活性。通过比较分析 Bacillus sp.4和Phaeobacter sp.1生物被膜的生物量及胞外产物发现,肠道细菌被膜细菌密度、膜厚和胞外脂类对厚壳贻贝幼虫的附着变态无影响,而胞外蛋白和胞外多糖可以影响幼虫的附着变态;对于厚壳贻贝稚贝的附着,肠道细菌被膜细菌密度、膜厚和胞外α-多糖均能影响其诱导活性,而胞外脂类和胞外蛋白无影响。本研究成果可为提高厚壳贻贝的健康生态养殖相关技术提供相关的指导,为解析生物被膜调控厚壳贻贝附着机制和该物种生态健康养殖提供理论依据。  相似文献   

9.
本文研究了13个2-(N-芳基氨甲基)苯并异噻唑啉-3-酮类化合物对球等鞭金藻Isochrysis galbana、亚心形扁藻Platymonas subcordiformis及舟形藻Navicula的生长抑制性能,并测试了其对藤壶二期无节幼虫的生物活性。结果表明:2-(N-芳基氨甲基)苯并异噻唑啉-3-酮类化合物对球等鞭金藻、亚心形扁藻和舟形藻都有良好的生长抑制活性,其中对球等鞭金藻和亚心形扁藻的抑制作用较强;对藤壶幼虫的生物活性测试表明,化合物最低质量浓度为2.0 mg/L时,除化合物g和l,都具有良好的生长抑制活性。化合物的结构与浮游生物的生长抑制活性关系表现为间位取代优于对位取代。  相似文献   

10.
开发绿色环保防污剂是海洋船舶防污涂料研究的重要方向,查明防污活性化合物分子结构中的防污活性基团,是设计开发新型防污剂的关键。本文合成了三种结构相似的苯酰胺类化合物HNOB、DOLPA和DHNOB,通过FTIR,1H NMR,13C NMR测试表征三种化合物的分子结构,利用典型污损生物硅藻和贻贝作为目标生物,测试其对硅藻和贻贝附着的影响,并将分子结构与防污活性进行对比,初步探讨影响防污性能的活性基团。硅藻和贻贝附着实验均表明,HNOB的防污性能较好,半数抑制浓度远低于DOLPA和DHNOB。通过结构对比分析发现,极性和非极性结构的协同作用比单一的极性基团或非极性长碳链基团能更好地赋予苯酰胺类物质良好的防污性能。该研究初步探讨了苯酰胺类化合物的构效关系,有助于新型防污活性化合物的设计开发和结构优化,并对探究该类化合物防除污损生物附着的机理和快速筛选有潜力的防污化合物具有重要意义。  相似文献   

11.
研究海洋污损生物藤壶(Barnacle)不同生长阶段附着强度,可为科学制定藤壶清除规范及设计相关机械设备提供依据。本文采用浸泡法在湛江调顺岛(21°31''N,110°41''E)实海中挂板,结合形貌观察藤壶生长过程,利用自行设计的剪切强度测试装置,选取网纹藤壶测试不同生长阶段剪切强度。结果表明:试板浸泡10 d,幼体藤壶开始附着;30 d试板表面藤壶覆盖面积约占30%,基底直径1~6 mm,部分藤壶死亡形成空壳;60 d试板约50%面积被藤壶覆盖,试板表面有覆膜,空壳现象加剧,藤壶基底直径最大达10 mm;90 d试板约95%面积被藤壶覆盖,出现藤壶相叠现象,基底直径1~13 mm。藤壶附着生长过程中,剪切强度变化符合“快-慢”的特点,以藤壶基底直径为变量,构建藤壶剪切强度Logistic增长模型,决定系数R2=0.99,说明模型拟合良好。利用构建的Logistic增长模型将藤壶剪切强度划分为速增期(基底直径4.0~6.4 mm),缓增期(基底直径6.4~8.7 mm)及渐停期(基底直径>8.7 mm)3个阶段。结合藤壶附着生长过程,藤壶在附着后采用机械方式清除的最佳清除时期在速增期。  相似文献   

12.
Secondary metabolites protect many marine sponges (Phylum: Porifera) from settlement by fouling organisms. Previous studies on the subtidal demosponge Axinella verrucosa collected in the Western Mediterranean led to the isolation of compounds that inhibited the settlement of cyprids larvae of the intertidal barnacle Balanus amphitrite, and the enzyme chitinase, which plays a key role in the molting cycle of crustaceans. However, in a field survey conducted at three locations in Israel, Eastern Mediterranean Sea, we observed that A. verrucosa is fouled by the subtidal barnacle Balanus trigonus, a previously unknown association. Settlement inhibition assays using B. amphitrite with chemical extracts from Israeli A. verrucosa and Axinella polypoides, a sympatric, congeneric sponge that seems not to be fouled by B. trigonus, showed that cyprid larvae of B. amphitrite were inhibited by the extracts of both sponges from settlement at concentrations several magnitudes lower than natural volumetric extract concentration in the sponges. These results indicate that, unlike the intertidal barnacle B. amphitrite, the subtidal B. trigonus is unaffected by the compounds from A. verrucosa, stressing and underlining the importance of using suitable target organisms (i.e. from the same habitat) to test for ecologically relevant antifouling activities.  相似文献   

13.
Abstract. Three species of Alvinellidae are found on walls of some hydrothermal chimneys at 13o N on the East Pacific Rise (EPR); numerous epibiotic bacteria were associated with two of these polychaetes, Alvinella pompejana and Alvinella caudata , but not with the third, Paralvinella grasslei. Many studies suggest that chemoautotrophic bacteria play a prominent role in deep-sea hydrothermal vent ecosystems. Particularly important are the intracellular bacteria present in the giant pogonophores and bivalve molluscs.
The abundant epibioses observed on these Alvinella species are unusual and the relationships between these bacteria and the worms are unknown. Previous results, including 13C values, morphological insertion of the bacteria on the epidermis, presence of ribulose biphosphate carboxylase, and fixation of 14C bicarbonate in some bacteria and in the dorsal epidermis, suggest that a trophic relationship could exist between Alvinella and its epibiotic bacteria. The present study compared the incorporation area of 14C bicarbonate in the 3 species. Paralvinella , which is devoid of epibiotic bacteria, served as a control.  相似文献   

14.
本文采取传统的醇沉水溶的工艺提取了深海细菌的胞外聚合物(extracellularpolymericsubstance,EPS),使用过氧化氢作为损伤剂建立SH-SY5Y人神经母细胞瘤体外氧化损伤模型。在安全剂量下评价EPS的体外神经保护活性,确定16种活性良好(细胞活力>90%)的EPS。16种EPS的成分分析结果如下:1)16种EPS的分子量分布呈三段式,分别为>200 kDa, 10~200 kDa和<10 kDa; 2)16种EPS单糖组成中除甘露糖、葡萄糖外,还有稀有单糖氨基葡萄糖、鼠李糖、葡萄糖醛酸、氨基半乳糖、半乳糖、岩藻糖; 3)EPS的总糖含量为14.06%~21.40%,蛋白含量为10.66%~31.05%,硫酸基含量为2.91%~26.53%。通过对相应菌株进行16SrDNA全序列分析并与GenBank比对,完成了活性菌株的鉴定,通过MEGA7.0和Figtree构建系统进化树。鉴定结果表明,16株深海细菌归属于3门8科9属16种,分布在三个门类:厚壁菌门(Firmicutes, 9/16),变形菌门(Proteobacteria, 6/16)和...  相似文献   

15.
对海洋细菌来说铁是一种必需元素,对铁吸收与利用的调控在细菌生长和防止铁毒性中起重要作用,在革兰氏阴性细菌中,铁的代谢由铁吸收调节蛋白(Fur) 来调控.橙色交替单胞菌是1种具有广泛抑菌谱的有益菌,本研究克隆表达了橙色交替单胞菌的fur基因,并分析了其相关特征.该基因序列中包含447bp的开放阅读框,编码148个氨基酸残基的蛋白,推导的相对分子量为16.637 kD,与GenBank报道的革兰氏阴性菌的相应序列同源性很高,其中氨基酸序列的中段从G47位至D104位,为高度保守区域.在限铁和富铁培养条件下铁载体分泌量的结果分析表明,fur基因可在大肠杆菌中大量表达,为进一步研究Fur蛋白的结构与功能打下基础.  相似文献   

16.
通过紫外分光光度计测定了海洋微生物需钠弧菌 Vibrio natriegens 的生长曲线,通过扫描电镜和原子力显微镜观测了该细菌在船舶用结构钢(DH32)钢样表面成膜过程及试样腐蚀形貌,探讨了生物膜的形成过程及其对材料表面腐蚀的影响。结果表明,生物膜的形成过程与微生物生命活动关系密切。根据对比暴露在菌液和无菌培养基中的试样表面形貌,发现细菌的附着及成膜过程的不均匀性,改变了DH32钢样表面的物理和化学状态。细菌附着区与周围形成的氧浓差电池,以及细菌新陈代谢主要产物对金属离子的络合,共同促进了试样局部腐蚀加速。  相似文献   

17.
The e?ect of the bacterial strain CI4 on the germination of spores from the green alga Ulva pertusa was assayed and it was found that the bacterial bioˉlm and cell-free supernatant strongly inhibited spore germination. In attempts to deˉne the chemical nature of the antifouling substance in the supernatant of CI4, the culture supernatants were tested for activity after heat treatment, enzy- matic treatments, size fractionation, and separation into aqueous and organic fractions. Results suggest that this bacterium produces an extracellular component with speciˉc activity toward algal spores that was heat-sensitive and between 3 and 10 kDa in molecular size. The exposure of the organic phase fraction to spores showed inhibitive e?ect on spore germination. Pronase and car- boxypeptidase y did not signiˉcantly a?ect the activity of inhibitory component, suggesting that the component was not a protein or a peptide. The bacterium CI4 was identiˉed as Pseudoalteromonas haloplanktis based on the phenotypic characters and 16S rRNA gene analysis.  相似文献   

18.
1Introduction Antarctica is often viewed as one of earth s lastgreat frontiers. Low temperature, high gradients insalinity, and strong ultraviolet radiation combinedwith lowlight conditions provide inhospitable condi-tions for life. Surviving in these ext…  相似文献   

19.
Coral mucus covers the surface of coral and contains antibacterial substances as a first line of defense. Coral mucus not only enables the coral itself to resist disease, but also provides antibacterial agents for people. We collected mucus from a scleractinian coral (Symphyllia gigantea) at Sta. Sanya (China), then extracted the antibacterial substances using 10% glacial acetic acid with the help of antiprotease inhibitors, and tested the antibacterial activity by a terrestrial bacterium (Staphylococcus aureus) and a marine bacterium (Vibrio anguillarum). The result showed that, there were antibacterial agents in the mucus, and their antibacterial activities were lost by treatment of the sample at 90 ℃ water for 10 min.  相似文献   

20.
A two-dimensional hydrodynamic and particle tracking model was used to estimate the dispersion and retention of barnacle larvae from their possible spawning sites in a tropical monsoon-influenced estuarine system (central west coast of India). Validation of the hydrodynamic simulations yielded a good match with field measurements. The pattern of larval dispersal in the region varied with the winds and currents. The seasonal changes in abundance could be attributed to physical forcing and weather conditions. The extent of barnacle larval dispersal from spawning sites varied from 10 to 78 km for different sites and seasons. During a 24-h cycle, the larval abundance showed one to two peaks in the estuarine area. The increased larval abundance is favored by the flood currents, pushing the larvae into the estuary. Physical forcing in the region helps in transport of the larvae from their spawning sites hugging to the coast and contributing to the population within the estuary. Field observations and numerical experiments suggest the occurrence of higher larval abundance in the estuary during post-monsoon. The dispersal pattern indicated that the barnacle population present in the estuary is well mixed, and with a seasonally changing pattern.  相似文献   

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