Identification of an ATP-binding cassette transporter for export of the O-antigen across the inner membrane in Rhizobium etli based on the genetic, functional, and structural analysis of an lps mutant deficient in O-antigen.

TitleIdentification of an ATP-binding cassette transporter for export of the O-antigen across the inner membrane in Rhizobium etli based on the genetic, functional, and structural analysis of an lps mutant deficient in O-antigen.
Publication TypeJournal Article
Year of Publication2001
AuthorsLerouge, I., T. Laeremans, C. Verreth, J. Vanderleyden, C. Van Soom, A. Tobin, and R. W. Carlson
JournalJ Biol Chem
Volume276
Issue20
Pagination17190-8
Date Published2001 May 18
ISSN0021-9258
KeywordsAmino Acid Sequence, ATP-Binding Cassette Transporters, Bacteria, Biological Transport, Cell Membrane, Cytoplasm, Lipopolysaccharides, Molecular Sequence Data, O Antigens, Open Reading Frames, Phylogeny, Protein Transport, Rhizobium, Sequence Alignment, Sequence Homology, Amino Acid
Abstract

For O-antigen lipopolysaccharide (LPS) synthesis in bacteria, transmembrane migration of undecaprenyl pyrophosphate-bound O-antigen oligosaccharide subunits or polysaccharide occurs before ligation to the core region of the LPS molecule. In this study, we identified by mutagenesis an ATP-binding cassette transporter in Rhizobium etli CE3 that is likely responsible for the translocation of the O-antigen across the inner plasma membrane. Mutant FAJ1200 LPS lacks largely the O-antigen, as shown by SDS-polyacrylamide gel electrophoresis and confirmed by immunoblot analysis. Furthermore, LPS isolated from FAJ1200 is totally devoid of any O-chain glycosyl residues and contains only those glycosyl residues that can be expected for the inner core region. The membrane component and the cytoplasmic ATP-binding component of the ATP-binding cassette transporter are encoded by wzm and wzt, respectively. The Tn5 transposon in mutant FAJ1200 is inserted in the wzm gene. This mutation resulted in an Inf- phenotype in bean plants.

DOI10.1074/jbc.M101129200
Alternate JournalJ. Biol. Chem.
PubMed ID11279176
Grant ListGM39583 / GM / NIGMS NIH HHS / United States