Structural (shape-maintaining) role of the cell surface glycoprotein of Halobacterium salinarium

The obligate halophile, Halobacterium salinarium, maintains a rod-shaped morphology under normal growth conditions. Lactoperoxidase(EC 1.11.1.7;donor:hydrogen-peroxide oxidoreductase)-catalyzed iodination and treatment with proteolytic enzymes were used to demonstrate that the recently described envelope glycoprotein (Mescher, M.F. & Strominger, J.L. (1976) J. Biol. Chem. 251, 2005-2014) is the only major cell surface component of this organism. The morphological changes that accompany alteration of the structure of the glycoprotein by growth in the presence of bacitracin or its removal with proteolytic enzymes strongly suggest that it forms a rigid matrix at the cell surface and is responsible for maintenance of the characteristic rod shape.