南大西洋热液区盲虾虾鳃可培养附生菌多样性分析

对来自于南大西洋洋中脊(SMAR)的盲虾Rimicaris sp.虾鳃中的附生好氧菌及厌氧菌进行了富集培养,共分离得到14株低温好氧菌和2个稳定的厌氧富集菌群.通过对好氧菌的16S rDNA序列系统发育分析,发现14株低温分离菌株分别属于海源菌(Idiomarina)、海杆菌(Marinobacter)、涅斯捷连科氏菌(Nesterenkonia)、赤杆菌(Erythrobacter)、盐单胞菌(Halomonas)、交替单胞菌(Alteromonas)、嗜冷菌(Psychrobacter)、Mesonia8个属,其中9株属于变形菌门(2株属于α-变形菌纲,占总菌株数的14.3％;7株属于γ-变形菌纲,占总菌株数的50.0％).对2个厌氧富集菌群的16S rDNA文库的39个阳性克隆子进行分析,获得2种基因型,分别为γ-变形菌纲的产碱杆菌属(Alcaligenes)和β-变形菌纲的嗜麦芽寡营养单胞菌属(Stenotrophomonas).结果表明,南大西洋洋中脊盲虾虾鳃附生菌类型较为丰富,对于附生菌的研究能够更加全面的认识盲虾与附生菌之间的相互作用.     

深海来源芳烃类降解菌筛选与盐单胞菌芘降解能力测定

海洋来源的菌株在高盐污水类修复处理中有重要的应用前景,而烃类物质是污水中的重要组成部分,其中含有多个苯环的芳香烃族化合物,对人类和环境具有较大的毒性,而目前关于多环芳烃(PAHs)厌氧代谢的相关报道相对较少。本研究以PAHs(萘、菲和芘等)为唯一碳源和能源,通过厌氧富集对太平洋深海沉积物中的PAHs降解菌展开研究。富集物细菌菌群分析结果表明,盐单胞菌属(Halomonas)、海旋菌属(Thalassospira)、海杆菌属(Marinobacter)、海洋杆菌属(Oceanobacter)和食烷菌属(Alcanivorax)等是主要的功能类群;其中盐单胞菌属是最主要的功能类群。通过筛选分离获得一高效烃降解盐单胞菌株,鉴定并命名为泰坦尼克盐单胞菌(Halomonas titanicae) PA16-9,该菌与模式菌株Halomonas titanicae BH1^T的16S rRNA相似性为99.52%。基于16S rRNA基因序列比对搜寻NCBI数据库,发现Halomonas titanicae广泛存在于废水、活性污泥、油田、湿地等有机质复杂区域,生态位分布极广,可...     

深海沉积物中龙须菜降解菌群的筛选与鉴定及多样性分析

以龙须菜为唯一的营养源对深海沉积物进行富集和筛选,获得一个可降解龙须菜(Gracilaria lemaneiformis)、紫菜(Porphyra umbilicalis)和海带(Laminaria japonica)产生还原性寡糖的菌群.通过16S rRNA序列及16S rRNA-RFLP分析对该菌群中的细菌多样性进行了研究.结果表明,降解菌群中的细菌组成主要为弧菌属(Vibrio,8株)、火色杆菌属(Flammeovirga,7株)和希瓦氏菌属(Shewanella,5株),其中希瓦氏菌属和火色杆菌属的细菌在菌群中的丰度较高.采用龙须菜为唯一营养源的筛选培养基对菌群中的细菌进行分离,获得4株具有琼胶酶活力的细菌,包括2株火色杆菌属和2株希瓦氏菌属细菌.培养和未培养的结果均表明火色杆菌和希瓦氏菌这2个属为所研究的深海沉积物主要的龙须菜降解菌.对原始降解菌群和所分离的关键菌株进行了龙须菜酶解产糖能力的比较,结果发现菌群中的弧菌属菌株虽然自身没有酶解龙须菜的能力,但可能可以协助关键菌株,提高菌群对龙须菜的降解效率.因此本研究中所获得的菌群和菌株有望在琼胶寡糖的绿色生产中得到广泛应用.     

九孔鲍鲍苗脱板期养殖环境细菌分离及分子鉴定

为了解九孔鲍鲍鱼脱板期养殖环境中细菌的多样性,分离培养了脱板病发生期养殖环境(包括附着基上和养殖池水中)细菌32株,并用限制性片段长度多态性分析和16S rDNA序列分析法对其进行了分子鉴定,构建了系统进化树.结果表明,所分离的细菌分为3大类群9个属,分别是:γ-变形菌纲(γ-Proterbacteria)的交替假单胞菌属(Pseudoalteromonas)、Cobetia属、盐单胞菌属(Hlomonas)、弧菌属(Vibrio)和海单胞菌属(Marinomonas);厚壁菌门(Firmicutes)的盐水球菌属(Salinicoccus)、动球菌属(Planococcus)和芽孢杆菌属(Bacillus);还有拟杆菌门(Bacteroidetes)的Tenacibaculum属.这些细菌大多与GenBank库中分离自发病的水产养殖生物的细菌最相似.这说明从该养殖环境中分离培养出的细菌和水产养殖病害间存在着一定的关系.     

水分条件对滨海芦苇湿地土壤微生物多样性的影响

滨海湿地因受河流和海水的交互作用,其土壤氧化还原电位及营养元素等条件复杂且处于不断变化之中,为了阐明此种环境下不同水分条件对滨海芦苇湿地土壤微生物多样性的影响,尤其是对铁还原菌群落结构的影响,作者以黄河三角洲滨海湿地为对象,研究了淹水和非淹水芦苇湿地表层(0~30 cm)土壤理化特性、微生物多样性(采用T-RFLP技术)和培养条件下湿地土壤微生物的Fe(III)还原能力的变化。结果表明,淹水芦苇湿地土壤有机碳、全氮、盐度、Fe(II)含量和pH值显著(P0.05)高于非淹水芦苇湿地土壤,而淹水芦苇湿地土壤铵态氮含量显著(P0.05)低于非淹水芦苇湿地。淹水芦苇湿地土壤主要优势细菌和古菌分别为铬还原菌属(Alishewanella)、纤维单胞菌属(Cellulomonas)、鞘脂单胞菌属(Sphingomonas)、假单胞菌属(Pseudomonas)和甲烷杆菌属(Methanobacterium)、甲烷八叠球菌属(Methanosarcina);而纤维单胞菌属、食酸菌属(Acidovorax)、地杆菌属(Geobacter)、硫杆菌属(Thiobacillus)和甲烷八叠球菌属分别为非淹水芦苇湿地土壤主要优势细菌和古菌。淹水芦苇湿地土壤主要优势铁还原菌为副球菌属(Paracoccus)、地杆菌属、铬还原菌属和硫单胞菌属(Thiomonas),而非淹水芦苇湿地土壤为地杆菌属和固氮螺菌属(Azospira)。说明淹水能增加芦苇湿地土壤细菌、古菌和铁还原菌的多样性。培养条件下,淹水芦苇湿地土壤铁还原菌的还原Fe(III)能力在培养后期(25d后)低于非淹水芦苇湿地,说明淹水条件在一定程度上抑制了芦苇湿地土壤铁还原菌的铁还原能力。     

南海冷泉区贻贝(Bathymodiolus platifrons)附生菌的分离培养与多样性分析

以采集后适应培养0~24 h以及添加甲烷和硫化钠培养24~240 h的南海冷泉区深海贻贝(Bathymodiolus platifrons)为材料,取其鳃部,分析附生菌的多样性与适应性变化状况。共分离鉴定出贻贝附生菌270株,对菌株的16S r DNA进行聚类分析,结果表明所分离菌株主要分布在4个门,21个属,其中变形菌的数量最多且多样性高。分析发现原位新采集的贻贝鳃部附生菌的多样性较高,6 h后附生菌的多样性明显降低。分别添加甲烷和硫化钠对深海贻贝进行培养,甲烷组与碳代谢有关的假单胞菌的数量逐渐增多,且在甲烷组240 h中发现2株食烷菌属菌株。硫化钠组的芽孢杆菌属所占比例升高。此外还发现4株潜在的新种。本研究实现了深海冷泉区贻贝的实验室培养,并对贻贝鳃部附生菌群结构进行了分析,丰富了海洋极端环境微生物资源库,并为深入解析贻贝与其附生菌之间的相互作用关系奠定了基础。     

凡纳滨对虾(Litopenaeus vannamei)循环水养殖系统中养殖效果及菌群结构和功能研究

循环水养殖可有效减少病原体的入侵,是我国水产养殖业发展的重要方向。为完善凡纳滨对虾(Litopenaeus vannamei)循环水养殖系统,采用生态调控、16S rRNA高通量测序、宏基因组学分析与数理统计等方法,系统分析了对虾循环水养殖系统中水质指标变化与菌群结构和基因功能的关系。结果显示,养殖池水质指标包括温度、溶解氧、盐度、pH以及氨氮0.11~1.16mg/L,亚硝酸氮0.10~0.66mg/L,硝酸氮0.84~35.40mg/L均在安全范围内;经过63d养殖,凡纳滨对虾平均体重达到11.78g左右,产量为3.28kg/m³左右,存活率为69.59%左右。菌群结构与功能分析结果显示:在开始运行期与水质变化平稳期生物滤池中菌群结构差异较大。在开始运行期海杆菌属(31.37%)占绝对优势,而在平稳期则以分枝杆菌属(6.65%)、分枝菌酸杆菌属(6.39%)、食烷菌属(5.21%)、海杆菌属(3.36%)、中慢生根瘤菌属(2.30%)、红杆菌属(1.34%)、副球菌属(1.29%)等反硝化细菌和硝化杆菌属(1.17%)占据优势。通过比对KEGG数据库发现涉及碳水化合物代谢和氨基酸代谢的蛋白数目最多,说明异养反硝化菌需要利用多种碳源来执行反硝化功能。     

青岛近海样品中聚丙烯微塑料降解微生物的富集培养及活性研究

本文以PP为唯一碳源对青岛近海海水和沉积物样品中的微生物进行实验室富集培养,对不同富集时间的富集水样及微塑料附着细菌的群落结构进行分析并对富集40 d的PP附着细菌进行分离、鉴定及PP降解活性检测。通过16S rRNA基因高通量测序及分析,发现PP附着细菌出现明显的群落演替,群落多样性随富集时间的延长而增大。PP附着细菌在富集过程中,γ-变形菌纲假单胞菌属(Pseudomonas)和不动杆菌属(Acinetobacter)细菌占绝对优势,其次为α-变形菌纲扎瓦尔金氏菌属(Zavarzinia)及拟杆菌纲(Bacteroidia)细菌。富集培养获得的铜绿假单胞菌LXI681(Pseudomonas aeruginosa)和反硝化无色杆菌LXI668(Achromobacter denitrificans)对PP具有降解活性。本研究为缓解PP微塑料污染提供了潜在的微生物菌种资源。     

雅浦海沟深海沉积物可培养真菌多样性及其反硝化能力研究

自雅浦海沟4个站位的12个沉积物样品中分离得到38株真菌菌株,基于形态观察和ITS序列信息对所得菌株进行分类鉴定,发现它们分别属于青霉属(Penicillium,17株)、曲霉属(Aspergillus,7株)、篮状菌属(Talaromyces,1株)、枝孢属(Cladosporium,6株)、赭霉属(Ochroconis,1株)、Meyerozyma属(1株)、梅拉菌属(Meira,1株)、Cystobasidium属(2株)、Wallemia属(1株)和红酵母属(Rhodotorula,1株)等10个属.其中青霉属、曲霉属和枝孢属菌株为优势菌株,分别占分离菌株总数的44.7%、18.4%和15.8%;而Wallemia属(节担菌纲)菌株是首次从深海环境中分离到.利用PCR技术在分离的深海真菌菌株中检测nir K和P450nor两种反硝化关键酶基因,结果显示nir K基因可在黄曲霉(Aspergillus flavus)、黑曲霉(Aspergillus niger)、杂色曲霉(Aspergillus versicolor)、枝孢菌(Cladosporium sp.)、枝状枝孢(Cladosporium cladosporioides)和产黄青霉(Penicillium chrysogenum)等6种真菌菌株中检测到,而P450nor基因仅在黄曲霉菌株中检测到.同时还通过富集培养方法从上述沉积物样品中分离获得两株反硝化枝孢菌.结果表明,雅浦海沟深海沉积物环境中存在着丰富的真菌资源,它们在深海环境氮循环中起着一定作用,这将增强人们对深海环境可培养真菌多样性及其生态作用的认识.     

烟台海域中度嗜盐菌分离、鉴定和系统进化研究

为研究山东烟台海域中度嗜盐菌的分布情况及种群特征,从烟台近海盐场采集的土样和水样中利用高氏一号培养基分离得到22株中度嗜盐菌。通过菌落形态观察、生理生化特征分析比较,选取其中的9株进行16SrDNA序列分析和系统进化分析,结果表明这些中度嗜盐菌分别属于7个属:芽孢杆菌属(Bacillus)、枝芽孢杆菌属(Virgibacillus)、薄壁芽孢杆菌属(Gracilibacillus)、刘氏菌属(Liuella)、产微球茎菌属(Microbulbifer)、拟诺卡氏菌属(Nocardiopsis)和交替单胞菌属(Alteromonas),其中菌株YTM-8、YTM-12和YTM-13可能是潜在的新种。以上研究结果表明烟台海域中存在有较为丰富的嗜盐微生物多样性,并且潜藏着新类型的嗜盐菌资源。     

南沙深海沉积物中石油降解菌的分离鉴定和多样性分析

为了解我国南沙海域中石油降解菌的多样性,认识其在环境自净中作用并获得用于石油污染生物修复的菌种资源,以不同链长烷烃及支链烷烃对南沙深海沉积物样品进行富集与烃降解菌的分离鉴定,并结合16S rRNA基因文库和DGGE技术对降解菌群的结构进行了分析.结果表明：通过16S rRNA基因文库构建及PCR-DGGE分析发现,不同链长烷烃富集后的菌群中,食烷菌（Alcanivorax）在各降解菌群中都是绝对优势菌;另外,除烃海杆菌（Marinobacter hydrocarbonoclasticus）、海绵假单胞菌（Pseudomonas pachastrellae）,以及Idiomarina与Kangiella属的细菌也是菌群中较重要的优势菌.此外,通过2种平板培养基从烷烃富集的降解菌群中分离获得了8个不同属的细菌.本研究还首次发现Kangiella属（食烷菌科）的细菌可能参与了烷烃降解.南沙沉积物烷烃降解菌多为γ-Proteobacteria;其中,食烷菌科（Alcanivoraceae）（Alcanivorax与Kangiella属）的细菌在降解菌群中是绝对优势菌,假单胞菌与海杆菌在烷烃降解过程中也起着重要作用.     

Effect on marine sediment nitrogen fluxes caused by organic matter enrichment with varying organic carbon structure and nitrogen content

Enrichments with five types of organic carbon, differing in nitrogen content and type of organic carbon, were made to a marine sediment in order to study effects on nitrogen fluxes. The enrichments used were Ulva lactuca, Ascophyllum nodosum, Zostera marina, Ceratium spp., lignin, and mixtures of U. lactuca and A. nodosum. Fluxes of ammonium, nitrate, and phosphate were measured in short-term (48 h) microcosm experiments, using a carbon enrichment loading similar to that at the sampling site. Changes in microbial community growth and structure due to three types enrichments were also detected using molecular methods in a microcosm experiment run for 4 days to allow for detection at DNA-level.Ammonium fluxes changed from an efflux in the control to an influx for all enrichments apart from U. lactuca. The change was significantly related to the added material's C:N ratio when Ceratium spp. was excluded. All enrichments induced an influx of nitrate suggesting the formation of anoxic micro zones, but there was no relationship with C:N ratio. Instead, the magnitude of the nitrate influx is suggested to be related to the structure of the organic carbon, where enrichments containing a large pool of cellulose and lignin (Z. marina and lignin) gave rise to a lower influx, compared to algal material with more easily degraded organic matter like lipids and starch, which induced the highest influx of nitrate (Ceratium spp., U. lactuca, and A. nodosum). The occurrence of an ammonium influx together with increased nitrate influx and a lower efflux of phosphate in the enrichments suggests a growth of heterotrophic bacteria. This was also confirmed using molecular methods (PCR-DGGE) where the relative abundance of bacterial species in the enrichments increased.The sum of ammonium and nitrate fluxes showed that total nitrogen removal was enhanced in all enrichments compared to the nonenriched control sediment, but in different ways. Ceratium spp. induced the highest removal followed by A. nodosum, U. lactuca, Z. marina, and lastly, by lignin. The same pattern was observed also in a second experiment. These results indicate that easily degradable organic carbon, together with a lower C:N ratio of the added material, will remove nitrogen from the water phase, making the recycling of nitrogen to the overlying water mass smaller.     

近海沉积物与水体中天然大分子聚合物降解菌的原位富集与多样性分析

本研究选取5种海洋动植物大分子高聚物或其天然组织,包括虾壳、鱼鳞、海带叶片、几丁质和壳聚糖,分别在海水表层和沉积物环境中进行富集,定期取样,通过高通量测序分析菌群多样性。结果发现,不同有机物原位富集的细菌多样性存在较大的差异,而且同种底物在海水表层与沉积物中的降解菌菌群差异较大。从物种多样性看,在海水表层环境中富集的鱼鳞样品种群最丰富,而沉积物环境中富集的海带叶片样品菌群多样性最低,除其优势菌群为热袍菌门外,其他所有富集物中优势菌均为变形菌门。其中脱硫杆菌科、黄杆菌科、脱硫弧菌科和弧菌科占有较大比例,脱硫杆菌科在所有样品中优势较大,黄杆菌科在海水表层环境样品中为优势菌群,弧菌科在沉积物样品几丁质和壳聚糖样品中占比较高。本研究通过对同种海洋环境中不同富集样品之间以及同种底物不同环境中富集菌群之间的比较,分析结果得到了原位条件下参与大分子聚合物降解的菌群种类,但有待于在更多不同的海域富集物中进行验证。     

Pore Water Nutrient Regeneration in Shallow Coastal Bohai Sea, China

The regeneration of pore water nutrients was studied and the contribution of benthic nutrient fluxes to the overlying water was evaluated on the basis of field specific observations conducted in September–October 1998 and April–May 1999 in the Bohai Sea. Nutrient concentrations in sediment pore waters were examined by incubating sediment core samples with overlying seawater in air and/or nitrogen conditions. Nutrient diffusion fluxes calculated by diagenetic equations were within a factor of 2 during incubations. The factors affecting nutrient diffusion across sediment/water interface include bioturbation, nitrification, denitrification, adsorption, and dissolution. The regeneration of nutrients from sediments will increase nutrient loads of the Bohai Sea and affect nutrient atomic ratios in this region. Among nutrient sources from riverine input, atmospheric deposition and sediment regeneration, ammonium and phosphate mainly came from atmospheric deposition (>50%); nitrate was mainly transported by riverine input into the Sea, silicate from sediment regeneration accounts up to 60%. This demonstrates that nutrient regeneration in sediments contributes more silicate than riverine input and atmospheric deposition together, but benthic flux contributes very much less phosphate and nitrate relative to riverine input and atmospheric deposition. The benthic fluxes of nutrients may lead to a decrease of the amount of nitrate, an increase of phosphate, ammonia and silicate in the water column. The release of silicate from sediments may compensate the decrease of silicate due to the reduction of riverine discharge. Nutrient regeneration in sediment may have an important influence on the eutrophic character of coastal waters in this region. This revised version was published online in August 2006 with corrections to the Cover Date.     

Dissolved free amino acids in coastal seawater using a modified fluorometric method

The method of Parsonset al. (1984) for measuring dissolved free amino acids (DFAA) in coastal seawater was modified. We found considerable interference in DFAA determination from ammonia dissolved in coastal seawater, although the interference of urea could be ignored. For DFAA analysis for coastal seawater samples, ammonia determinations for the same sample are needed to correct DFAA values. For coastal surface seawater samples from all over the Seto Inland Sea, Japan, values of DFAA ranged from undetectable to 1.87 μg-at N/l when corrected for ammonia, while uncorrected values ranged from undetectable to 2.61 μg-at N/l. DFAA, urea, nitrate+nitrite, ammonia and DON concentrations in surface seawater collected in the Seto Inland Sea were analyzed simultaneously. DFAA at four seasons constituted from 1.4 to 10.1% of DON, with a mean value of 6.5%. The concentration of urea was similar to that of DFAA and often higher than that of ammonium, although generally lower than that of nitrate.     

Satellite infrared remote sensing observation of surface circulation of the northeast South China Sea in winter

I~IOX \The investigation of physical oceanography in the South China Sea dates from early in the17th century and was carried out by scientists from many countries, including the United StateS,the United Kingdoms, Japan, .Russia and so on, but the survey area was rather limited at thattime and the data which were collected were still fragmentary. Since the 20th century, the investigation on the sleuth China Sea has made great progreSS not only in the scale of survey, but alsoin the depth …     

Bacterioplankton responses to iron enrichment during the SAGE experiment

We studied the microbial food web in the upper 100 m of the water column in iron-limited sub-Antarctic HNLC waters south-east of New Zealand in the SAGE experiment in 2004, with focus on bacterioplankton. Samples were collected daily from inside and outside the iron enriched patch. Short term enrichment experiments were conducted on board in 4 L polycarbonate bottles with water outside the iron enriched patch to study single and combined effects of micronutrient additions on microbial food web. Low bacterial growth was recorded in the study area with community turnover times of 50 h or more during the study period. Measurements of bacterial standing stocks and production rates in the study show minor responses to the large scale iron enrichment, with increase in rates and stocks after the first enrichment and at the end of the study period after the third iron enrichment when solar radiation increased and wind mixing decreased. The average daily bacterial production rates were 31.5 and 33.7 mgCm⁻² d⁻¹ for the OUT and IN stations, respectively; thus overall there was not a significant difference between the control and the iron-enriched patch. In the bottle experiments bacterial thymidine incorporation showed responses to single iron and silicic acid enrichments and a major growth response to the combined iron and sucrose enrichments. Phytoplankton chlorophyll-a showed clear stimulation by single additions of iron and silicic acid and silicic acid enhanced the iron impact. Cobalt additions had no effect on bacteria growth and a negative effect on phytoplankton growth. Low bacterial in situ growth rates and the enrichment experiments suggest that bacteria are co-limited by iron and carbon, and that bacterial iron uptake is dependent on carbon supply by the food web. With the high iron quota (??mol Fe mol C⁻¹) bacteria may scavenge considerable amounts of the excess iron, and thus influence the relative importance of the microbial food web as a carbon sink.     

南海上层季节环流局部分析与验证

研究南海环流的方法很多,采用GDEM资料,运用P矢量方法,得出了南海春季、夏季局部的上层流场分布情况.通过分析并结合UCM-60超声海流计和ADCP走航式测流仪相关实测数据,初步验证了这种研究南海上层季节环流所用的数值计算方法.     

南海海洋环流季节变化的数值模拟研究

基于POM(Princeton Ocean Model)海洋模式,对南海不同深度环流的季节性变化进行了数值模拟研究。模拟结果表明:南海表层和上层环流受季风影响,在夏季西南季风驱动下,南海表层环流在南部呈现强反气旋式结构,在南海北部则是一个弱的气旋环流;在冬季东北季风驱动下,南海表层环流结构呈气旋式,并且明显加强了沿越南沿岸向南流动的西边界流;春季和秋季为南海季风的转换期,其对应的环流特征也处于冬季环流与夏季环流的过渡流型,流速与冬季和夏季相比较弱。南海200m层环流的季节变化与表层相似。在500与1 000m层,则出现许多处中尺度漩涡,流场也变得较为紊乱。     

Biomarkers reveal the terrigenous organic matter enrichment in the late Oligocene-early Miocene marine shales in the Ying-Qiong Basin,South China Sea

The increase of total organic carbon content of the late Oligocene-early Miocene terrigenously-dominated marine shales in the shallower depth intervals was reported in the Ying-Qiong Basin, South China Sea. The organic enriched lower Sanya Formation shales(early Miocene) have biomarker characteristics of tropical/subtropical plants, with abundant high molecular weight n-alkanes, angiosperm-derived oleanane,rearranged oleananes Ⅰ, Ⅱ, Ⅱ, tricyclic/tetracyclic terpanes including des-A-oleanane, X, ...