Time series data of microbial communities

Time series abundances of bacterial prey species and their morphotypes appearing in time with and without a protist predator species. All microcosms were started with equal abundance for all prey species either with or without the predator (See "Notes" section in the data file for the descriptions of species). Static microcosms consisted of 20 mL Brunner-CR2 medium in 50-mL cell culture flasks, incubated at 25°C. Prey and predator numbers were adjusted in the experimental medium to 1.8 x 10⁷cells mL^-1 and 4.2 x 10⁴ cells mL^-1, respectively. During the experiment, we performed daily 10-fold dilutions by transferring 10% of the community into fresh medium. All microcosms were sampled 32 times (from 3 to 34 days ). All bacterial species were quantified by plating on Brunner CR-2 medium. All visible, differently coloured colonies were recorded after 2 days of incubation at 25°C using different dilutions from 10³ to 10⁸. Cell numbers of protist predator were estimated by counting cells fixed with 0.2% Lugol’s iodine solution under an inverted microscope with a counting chamber.

本数据集包含猎物细菌物种及其形态型在有、无原生生物捕食者（protist predator）条件下的时间序列丰度数据。所有微宇宙培养体系（microcosm）的初始接种阶段，所有猎物细菌物种的丰度均保持一致，无论是否添加捕食者；物种详细描述参见数据文件的"备注"章节。静态微宇宙培养体系采用50mL细胞培养瓶装载20mL Brunner-CR2培养基，于25℃条件下静置培养。实验培养基中猎物细菌与捕食者的初始接种浓度分别调整为1.8×10^7 细胞·毫升^-1与4.2×10^4 细胞·毫升^-1。实验期间每日转接10%的群落至新鲜培养基，完成10倍稀释传代。所有微宇宙培养体系共完成32次取样，取样时间跨度为第3天至第34天。所有细菌物种的丰度通过涂布平板法接种于Brunner CR-2培养基进行定量：于25℃培养2天后，采用10^3至10^8的不同稀释梯度涂布计数，记录所有可见的异色菌落。原生生物捕食者的细胞丰度通过如下方式估算：将细胞以0.2%卢戈氏碘液（Lugol’s iodine solution）固定后，利用带计数室的倒置显微镜进行细胞计数。