Microcosm: SEM micrographs of generation of exopolymeric substances (EPS) by phytoplankton and bacteria with and without polysaccharide inhibitor at various concentrations of WAF

Both phytoplankton and bacteria secrete extracellular enzymes actively that help them degrade the complex molecules to provide them simple carbon (sugars) and nitrogen (amino acids) molecules that can be easily assimilated. This process supports bacterial growth on exopolymeric substances (EPS) and helps support their cell division. However, this process does not lead to depletion of EPS, as only a fraction is consumed by bacteria. Due to the sticky nature of the EPS, the newly formed bacteria will tend to adhere to the EPS, and this will lead to the eventual formation and increase in the size of aggregates. To test this, we added DCB (2,6-dichlorobenzonitrile; an inhibitor of polysaccharide production in diatoms) to Thalassiosira pseudonana in the presence and absence of oil. This dataset contains the SEM micrographs documenting the phytoplankton, bacterial, and EPS changes in morphology. The confocal laser scanning microscopy (CLSM) micrographs depicting the changes in EPS and microbes showing the effects of DCB and WAF are available under GRIIDC UDI R6.x807.000:0028. The algal and bacterial growth in terms of enzyme assays, microbial cell counts, monosaccharide concentrations, and photosynthesis data at different WAF concentrations are available under GRIIDC UDI R6.x807.000:0022.

浮游植物（phytoplankton）与细菌均会主动分泌胞外酶（extracellular enzymes），协助其降解复杂大分子，从而获得可直接同化的简单碳（糖类）与氮（氨基酸）分子。该过程可支撑细菌在胞外聚合物物质（exopolymeric substances, EPS）表面生长，并助力细菌细胞分裂。不过这一过程并不会导致EPS被完全耗尽——因为仅有一小部分EPS会被细菌消耗。由于EPS具有黏性，新形成的细菌会倾向于附着在EPS表面，最终促使聚集体形成并不断增大。为验证这一机制，我们在有、无油类存在的条件下，向假微型海链藻（Thalassiosira pseudonana）中添加了DCB（2,6-二氯苯甲腈，硅藻多糖合成抑制剂）。本数据集包含扫描电子显微镜（scanning electron microscope, SEM）显微图像，记录了浮游植物、细菌及EPS的形态变化。可体现DCB与水容性油馏分（Water Accommodated Fraction, WAF）影响的、展示EPS与微生物变化的共聚焦激光扫描显微镜（confocal laser scanning microscopy, CLSM）图像，已上传至GRIIDC UDI R6.x807.000:0028。不同WAF浓度下的酶活性测定、微生物细胞计数、单糖浓度及光合作用数据所对应的藻类与细菌生长情况，已上传至GRIIDC UDI R6.x807.000:0022。