Marine eukaryotes and bacteria, Antarctica

Glass slides were deployed at 12m and 18m3 at sites in McMurdo Sound (adjacent to McMurdo Station, Scott Base and Cape Armitage) for a period of 12 months to collect biofilm.18S rDNA sequence information was obtained for representatives of each DGGE (denaturing gradient gel electrophoresis) band at each site and depth. This data was interrogated to phyla level: cnidaria, bryozoa, protozoa, dinoflagellates, arthropods, platyhelminths and annelids were present.Density of diatoms observed by fluorescence microscopy for each site and depth were recorded (per 100 µm2). At least 6 different diatom morphotypes were identified based on size and morphology.The slides were also examined by performing fluorescence in situ hybridization (FISH) reactions with bacteria-specific probes (Eub338), an archaea-specific probe (ARCH915) and 9 different bacterial group-specific probes. Bacterial groups identified from the sequences were: Gammaproteobacteria, SRB, Planctomycetales, Alphaproteobacteria, Archaea, Betaproteobacteria, Actinobacteria and Firmicutes, Cytophaga /Flavobacteria of Bacteroidetes (CFB), Verrucomicrobia.This study was the first to examine eukaryotic recruitment, potentially overlooked in visual surveys, using molecular techniques. To use molecular techniques to examine the community structure of marine eukaryotes and bacteria recruiting onto artificial substrata.

将载玻片部署于麦克默多湾（毗邻麦克默多站、斯科特基地与阿米蒂奇角）的12米与18米水深点位，为期12个月以收集生物膜。针对每个点位与水深下的每条变性梯度凝胶电泳（denaturing gradient gel electrophoresis, DGGE）条带的代表样本，获取了18S核糖体DNA（18S rDNA）序列信息。该数据被分析至门类层级：检出刺胞动物门、苔藓动物门、原生动物门、甲藻门、节肢动物门、扁形动物门与环节动物门。通过荧光显微镜观测各点位与水深下的硅藻密度，并以每100平方微米为单位记录结果；基于尺寸与形态特征，共鉴定出至少6种不同的硅藻形态型。同时通过荧光原位杂交（fluorescence in situ hybridization, FISH）技术对载玻片进行检测，使用了细菌特异性探针（Eub338）、古菌特异性探针（ARCH915）以及9种不同的细菌类群特异性探针。通过序列鉴定出的细菌类群包括：γ-变形菌纲、硫酸盐还原菌（SRB）、浮霉菌目、α-变形菌纲、古菌、β-变形菌纲、放线菌门、厚壁菌门、拟杆菌门的噬纤维菌/黄杆菌类群（CFB）以及疣微菌门。本研究首次采用分子技术探究了视觉调查中可能被忽略的真核生物附着过程，其核心目标为利用分子技术解析附着于人工基质的海洋真核生物与细菌的群落结构。