Electron micrographs of a syntrophically grown co-culture of Th. Phaeum andMethanothermobacter thermautotrophicus strain TM. A Young cell with flagellum. B Round structures on top of cells that might comprise bacteriophages; some show a tail-like structure (arrow). C Outgrown cells forming aggregates do not carry flagella.
Oehler et al. BMC Genomics 2012 13:723 doi:10.1186/1471-2164-13-723