Isolation of the fibrocrystalline body, a structure present in haloarchaeal species, from Halobacterium salinarum

An organized structure, the fibrocrystalline body (FB), has been isolated f rom the archaeon Halobacterium salinarum. The structure is also present in, and can be isolated from, other extreme halophilic archaea. FB is present in the cytoplasm during the exponential growth and early stationary phases. This structure is affected by vincristine, an antitumoral drug, which targ ets tubulin. The drug causes fragmentation of the FB. changes in the cell s hape, and growth inhibition. Taken together, these results point toward an important role in the life of the cell for this highly organized structure.