Publications

• The TagB protein in Bacillus subtilis 168 is an intracellular peripheral membrane protein that can incorporate glycerol phosphate onto a membrane-bound acceptor in vitro.

  Bhavsar A.P., Truant R., Brown E.D.

  Genes involved in the synthesis of poly(glycerol phosphate) wall teichoic acid have been identified in the tag locus of the model Gram-positive organism Bacillus subtilis 168. The functions of most of these gene products are predictable from sequence similarity to characterized proteins and have p ... >> More

  Genes involved in the synthesis of poly(glycerol phosphate) wall teichoic acid have been identified in the tag locus of the model Gram-positive organism Bacillus subtilis 168. The functions of most of these gene products are predictable from sequence similarity to characterized proteins and have provided limited insight into the intracellular synthesis and translocation of wall teichoic acid. Nevertheless, critical steps of poly(glycerol phosphate) teichoic acid polymerization continue to be a puzzle. TagB and TagF, encoded in the tag locus, do not show sequence similarity to characterized proteins. We recently showed that recombinant TagF could catalyze glycerol phosphate polymerization in vitro. Based largely on homology to TagF, the TagB protein has been proposed to catalyze either an intracellular glycerophosphotransfer reaction or the extracellular teichoic acid/peptidoglycan ligation reaction. Here we have taken steps to characterize TagB, particularly through in vivo localization studies and in vitro biochemical assay, in order to make a case for either role in teichoic acid biogenesis. We have shown that TagB associates peripherally with the intracellular face of the cell membrane in vivo. We have also produced recombinant TagB and used it to demonstrate the enzymatic incorporation of labeled glycerol phosphate onto a membrane-bound acceptor. The data collected from this and the accompanying study are strongly supportive of a role for TagB in B. subtilis 168 teichoic acid biogenesis as the CDP-glycerol:N-acetyl-beta-d-mannosaminyl-1,4-N-acetyl-d-glucosaminyldiphosphoundecaprenyl glycerophosphotransferase. Here we use the trivial name "Tag primase." << Less

  J. Biol. Chem. 280:36691-36700(2005) [PubMed] [EuropePMC]

• The amino terminus of Bacillus subtilis TagB possesses separable localization and functional properties.

  Bhavsar A.P., D'Elia M.A., Sahakian T.D., Brown E.D.

  The function(s) of gram-positive wall teichoic acid is emerging with recent findings that it is an important virulence factor in the pathogen Staphylococcus aureus and that it is crucial to proper rod-shaped cell morphology of Bacillus subtilis. Despite its importance, our understanding of teichoi ... >> More

  The function(s) of gram-positive wall teichoic acid is emerging with recent findings that it is an important virulence factor in the pathogen Staphylococcus aureus and that it is crucial to proper rod-shaped cell morphology of Bacillus subtilis. Despite its importance, our understanding of teichoic acid biosynthesis remains incomplete. The TagB protein has been implicated in the priming step of poly(glycerol phosphate) wall teichoic acid synthesis in B. subtilis. Work to date indicates that the TagB protein is localized to the membrane, where it adds a single glycerol phosphate residue to the nonreducing end of the undecaprenol-phosphate-linked N-acetylmannosamine-beta(1,4)-N-acetylglucosamine-1-phosphate. Thus, membrane association is critical to TagB function. In this work we elucidate the mechanism of TagB membrane localization. We report the identification of a membrane targeting determinant at the amino terminus of TagB that is necessary and sufficient for membrane localization. The putative amphipathicity of this membrane targeting determinant was characterized and shown to be required for TagB function but not localization. This work shows for the first time that the amino terminus of TagB mediates membrane targeting and protein function. << Less

  J. Bacteriol. 189:6816-6823(2007) [PubMed] [EuropePMC]

• In vitro reconstitution of two essential steps in wall teichoic acid biosynthesis.

  Ginsberg C., Zhang Y.H., Yuan Y., Walker S.

  Wall teichoic acids (WTAs) are anionic polymers that decorate the cell walls of many gram-positive bacteria. These structures are essential for survival or virulence in many organisms, which makes the enzymes involved in their biosynthesis attractive targets for the development of new antibacteria ... >> More

  Wall teichoic acids (WTAs) are anionic polymers that decorate the cell walls of many gram-positive bacteria. These structures are essential for survival or virulence in many organisms, which makes the enzymes involved in their biosynthesis attractive targets for the development of new antibacterial agents. We present a strategy to obtain WTA biosynthetic intermediates that involves a combination of chemical and enzymatic transformations. Using these intermediates, we have reconstituted the first two committed steps in the biosynthetic pathway. This work enables the exploration of WTA-synthesizing enzymes as antibiotic targets. << Less

  ACS Chem. Biol. 1:25-28(2006) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• A revised pathway proposed for Staphylococcus aureus wall teichoic acid biosynthesis based on in vitro reconstitution of the intracellular steps.

  Brown S., Zhang Y.H., Walker S.

  Resistance to every family of clinically used antibiotics has emerged, and there is a pressing need to explore unique antibacterial targets. Wall teichoic acids (WTAs) are anionic polymers that coat the cell walls of many Gram-positive bacteria. Because WTAs play an essential role in Staphylococcu ... >> More

  Resistance to every family of clinically used antibiotics has emerged, and there is a pressing need to explore unique antibacterial targets. Wall teichoic acids (WTAs) are anionic polymers that coat the cell walls of many Gram-positive bacteria. Because WTAs play an essential role in Staphylococcus aureus colonization and infection, the enzymes involved in WTA biosynthesis are proposed to be targets for antibiotic development. To facilitate the discovery of WTA inhibitors, we have reconstituted the intracellular steps of S. aureus WTA biosynthesis. We show that two intracellular steps in the biosynthetic pathway are different from what was proposed. The work reported here lays the foundation for the discovery and characterization of inhibitors of WTA biosynthetic enzymes to assess their potential for treating bacterial infections. << Less

  Chem. Biol. 15:12-21(2008) [PubMed] [EuropePMC]

  This publication is cited by 3 other entries.