Model of the Bacillus anthracis S-layer EA1

The Gram-positive and spore-forming bacterium Bacillus anthracis is the etiological agent of anthrax, a deadly disease that today affects mostly wildlife and livestock. Its vegetative cells are covered in a surface layer or S-layer composed of two mutually excluding proteins, Sap and EA1, present in the exponential and stationary growth phases respectively. Using X-ray crystallography we generate a model of the EA1 monomer (PDB ID: 8OPR) that shows the EA1 S-layer assembly domain consists of a beads-on-a-string architecture of 6 immunoglobulin-like domains (D1 - D6), where calcium binding structures interdomain contact loops and allows the protomers to adopt their assembly-competent conformation. Here we deposit the 3D coordinates of the EA1 S-layer model, generated based on a low resolution 3D cryoEM map, and docking of the EA1 X-ray structure and rigid body domain reorganisation of EA1 domain D2 (res 292-396), and validation by directed mutagenesis. See Sogues et al. 2023 "Structure and function of the EA1 surface layer of Bacillus anthracis" for experimental details and full description of biological data.