Myelin like electrogenic filamentation and Liquid Microbial Fuel Cells Dataset.

Biofilm at water-oil interface of hypoxic water columns of microcosms, prepared from a lacustrine sample, that used diesel as a carbon source was found to show electrogenic properties. These microcosms named, Liquid Microbial Fuel Cells (L-MFCs) were electrically characterized using a custom electronic analyzer; accurate determination of voltage (V), power density (W/m 2), and current density (A/m2) for both charge and discharge phases was carried out. The instrument made it possible to carry out cell characterizations using resistive loads between 0 Ω (Ohm) and 10 kΩ. During the hypoxic and electrogenic phase, the synthesis of a system of "bacterial piping induction", produced filaments of hundreds of micrometers in which the microbial cells are hosted. Ultrastructural microscopy collected by scanning (SEM), transmission (TEM), immunofluorescence, Thunder Imager 3D, confocal laser scanning (CLSM) microscopy revealed a "myelin like" structure during filamentation processes; this "myelin like" structure exhibited cross-reactivity towards different epitopes of the myelin basic protein (MBP) and Claudin 11 (O4) of human oligodendrocytes. The disclosure of these filamentation processes could be helpful to describe further unconventional microbial structures in aquatic ecosystems and of the animal world. The data that support the findings of this study are openly available in at https://data.mendeley.com/datasets/7d35tj3j96/1.

Electrogenic and hydrocarbonoclastic biofilm at the oil-water interface as microbial responses to oil spill.

The oil-water interface formed during an oil spill represents a challenging environment for pelagic communities living in aquatic ecosystems. At this anoxic barrier, we report the formation of a microbial hydrocarbonoclastic biofilm capable of electron transfer along the water column. This biofilm generated a membrane of surface-active compounds that allowed the spontaneous separation of electrical charges, causing the establishment of an anodic and a cathodic region and, as a result, the spontaneous creation of a liquid microbial fuel cell. Such floating biofilm was connected to the water column underneath by floating filaments that could contribute to oxygen reduction at distance. The filaments revealed an unusual lipid content induced by anoxic conditions, with prominent ultrastructural features similar to myelin found in oligodendrocytes of the vertebrate nervous system. Furthermore, these filaments showed an interesting cross-reactivity towards different epitopes of the myelin basic protein (MBP) and Claudin 11 (O4) of human oligodendrocytes. The presence of a network of filaments similar to myelin suggests the probable existence of evolutionary connections between very distant organisms. Collectively these results suggest a possible mechanism for how lake microbial communities can adapt to oil spills while offering an interesting starting point for technological developments of liquid microbial fuel cells related to the study of hydrocarbon-water interfaces. The data that support the findings of this study are openly available in figshare at https://figshare.com/s/72bc73ae14011dc7920d.