In situ structure of the SpoIVA layer involved in the assembly of the bacterial spore coat

The bacterial spore owes its remarkable resistance properties to its coat, one of the most resilient and durable biological structures on Earth. Assembled at the surface of the outer forespore membrane, the coat comprises dozens of proteins organized into distinct layers. Its formation is initiated by the interdependent localization of SpoVM and SpoIVA, which are proposed to form a polymeric scaffold for the innermost coat layer. This proposal aims to elucidate the structure of the coat layer formed by SpoVM and SpoIVA at the surface of Bacillus subtilis spores. Our goal is to obtain high-resolution tomograms of the coat layers to unravel molecular details of the SpoVM-SpoIVA layer and understand the mechanisms driving coat assembly.