Observation of the two-dimensional (2-D) 3 nm x 3 nm lattice structure of the S-layer sheath of the archaeobacterium Methanospirillum hungatei is reported for the first time by scanning tunneling microscopy. The samples consisted of sheath fragments deposited on a TaSe2 substrate and coated with a Pt/Ir film. In addition to confirming the 2-D structure, the images reveal some new information about the nano-scale details of the sheath structure. A lateral resolution of 1 nm was achieved, suggesting that the grain size of the Pt/Ir films was much less than for similar films deposited on a smooth metal surface.
Blackford, B. L.; Xu, W.; Jericho, M. H.; Mulhern, P. J.; Firtel, M.; and Beveridge, T. J.
"Direct Observation by Scanning Tunneling Microscopy of the Two-Dimensional Lattice Structure of the S-Layer Sheath of the Archaeobacterium Methanospirillum hungatei GP1,"
Scanning Microscopy: Vol. 8
, Article 9.
Available at: https://digitalcommons.usu.edu/microscopy/vol8/iss3/9