Tomographic reconstruction of treponemal cytoplasmic filaments reveals novel bridging and anchoring components

Authors

Jacques Izard, David Axelrod Institute for Public Health & State University of New York at AlbanyFollow
Bruce F. McEwen, Wadsworth Center, Biggs Laboratory & State University of New York at Albany
Rita M. Barnard, Wadsworth Center
Thomas Portuese, Wadsworth Center
William A. Samsonoff, Wadsworth Center
Ronald J. Limberger, David Axelrod Institute for Public Health & State University of New York at Albany

Date of this Version

10-6-2003

Citation

2003 New York State Department of Health

Comments

Molecular Microbiology (2004) 51 (3), 609–618 doi:10.1046/j.1365-2958.2003.03864.x

Abstract

An understanding of the involvement of bacterial cytoplasmic filaments in cell division requires the elucidation of the structural organization of those filamentous structures. Treponemal cytoplasmic filaments are composed of one protein, CfpA, and have been demonstrated to be involved in cell division. In this study, we used electron tomography to show that the filaments are part of a complex with a novel molecular organization that includes at least two distinct features decorating the filaments. One set of components appears to anchor the filaments to the cytoplasmic membrane. The other set of components appears to bridge the cytoplasmic filaments on the cytoplasmic side, and to be involved in the interfilament spacing within the cell. The filaments occupy between 3 and 18% of the inner surface of the cytoplasmic membrane. These results reveal a novel filamentous molecular organization of independent filaments linked by bridges and continuously anchored to the membrane.