Tapping a bacterial enzymatic pathway for the preparation and manipulation of synthetic nanomaterials.

We present a spherical micelle generated in a three-step sequence in which a farnesyl-pantetheine conjugate is phosphorylated, adenylated, and phosphorylated once more to generate a farnesyl-CoA amphiphile that self-assembles into spherical micelles. A sphere-to-fibril morphological switch is achieved by enzymatically transferring the farnesyl group of the farnesyl-CoA micelle onto a peptide via phosphopantetheinyl transferase to generate a peptide amphiphile. Each step in the sequence is followed with characterization by HPLC, MS, TEM, and DLS.

Structure, biochemistry, and inhibition of essential 4'-phosphopantetheinyl transferases from two species of Mycobacteria.

4'-Phosphopantetheinyl transferases (PPTase) post-translationally modify carrier proteins with a phosphopantetheine moiety, an essential reaction in all three domains of life. In the bacterial genus Mycobacteria, the Sfp-type PPTase activates pathways necessary for the biosynthesis of cell wall components and small molecule virulence factors. We solved the X-ray crystal structures and biochemically characterized the Sfp-type PPTases from two of the most prevalent Mycobacterial pathogens, PptT of M.

Resin supported acyl carrier protein labeling strategies.

The post-translational modifying enzymes phophopantetheinyl transferase and acyl carrier protein hydrolase have shown utility in the functional modification of acyl carrier proteins. Here we develop these tools as immobilized biocatalysts on agarose supports. New utility is imparted through these methods, enabling rapid and label-independent protein purification.

Chemoenzymatic exchange of phosphopantetheine on protein and peptide.

Evaluation of new acyl carrier protein hydrolase (AcpH, EC 3.1.4.

4-(3-Chloro-5-(trifluoromethyl)pyridin-2-yl)-N-(4-methoxypyridin-2-yl)piperazine-1-carbothioamide (ML267), a potent inhibitor of bacterial phosphopantetheinyl transferase that attenuates secondary metabolism and thwarts bacterial growth.

4'-Phosphopantetheinyl transferases (PPTases) catalyze a post-translational modification essential to bacterial cell viability and virulence. We present the discovery and medicinal chemistry optimization of 2-pyridinyl-N-(4-aryl)piperazine-1-carbothioamides, which exhibit submicromolar inhibition of bacterial Sfp-PPTase with no activity toward the human orthologue. Moreover, compounds within this class possess antibacterial activity in the absence of a rapid cytotoxic response in human cells.

Fluorescent techniques for discovery and characterization of phosphopantetheinyl transferase inhibitors.

Phosphopantetheinyl transferase (PPTase; E.C. 2.

Reversible labeling of native and fusion-protein motifs.

The reversible covalent attachment of chemical probes to proteins has long been sought as a means to visualize and manipulate proteins. Here we demonstrate the full reversibility of post-translational custom pantetheine modification of Escherichia coli acyl carrier protein for visualization and functional studies. We use this iterative enzymatic methodology in vitro to reversibly label acyl carrier protein variants and apply these tools to NMR structural studies of protein-substrate interactions.