Three-dimensional structure of the regularly constructed surface layer from Synechocystis sp. strain CLII.

The isolated, outermost cell wall layer from Synechocystis sp. strain CLII is described using electron microscopy and Fourier reconstruction to study the three-dimensional structure of the proteins within the layer to a resolution of ca. 3 nm. This surface layer forms regular hexagonal arrays (a = b = 15.2 nm). The two-dimensional space group is p6. The monomer proteins form hexamers arranged around a central hollow cylinder. The linkers between the hexamers are of the delta type and are located approximately in the central section between the top and bottom of the protein layer.