The mechanism of the phage-encoded protein antibiotic from ΦX174.

The historically important phage ΦX174 kills its host bacteria by encoding a 91-residue protein antibiotic called protein E. Using single-particle electron cryo-microscopy, we demonstrate that protein E bridges two bacterial proteins to form the transmembrane YES complex [MraY, protein E, sensitivity to lysis D (SlyD)]. Protein E inhibits peptidoglycan biosynthesis by obstructing the MraY active site leading to loss of lipid I production.

Estimated glomerular filtration rate with and without race for drug dosing: Cystatin C vs. serum creatinine.

The goal of this study was to use a model kidney function clearance-dependent drug (vancomycin) to understand the gain or loss of precision in dosing with use of serum creatinine (S ), serum cystatin C (S ) and race and nonrace-based equations of the estimated glomerular filtration rate (eGFR). In this study of hospitalized patients, we compared S , S and their combination to estimate kidney function and vancomycin clearance. The nonrace-based S eGFR model outperformed other clearance models and improved the probability of target attainment by 15%.

DPAGT1 Inhibitors of Capuramycin Analogues and Their Antimigratory Activities of Solid Tumors.

Capuramycin displays a narrow spectrum of antibacterial activity by targeting bacterial translocase I (MraY). In our program of development of new -acetylglucosaminephosphotransferase1 (DPAGT1) inhibitors, we have identified that a capuramycin phenoxypiperidinylbenzylamide analogue (CPPB) inhibits DPAGT1 enzyme with an IC value of 200 nM. Despite a strong DPAGT1 inhibitory activity, CPPB does not show cytotoxicity against normal cells and a series of cancer cell lines.

Substrate Tolerance of Bacterial Glycosyltransferase MurG: Novel Fluorescence-Based Assays.

MurG (uridine diphosphate--acetylglucosamine/-acetylmuramyl-(pentapeptide) pyrophosphoryl-undecaprenol -acetylglucosamine transferase) is an essential bacterial glycosyltransferase that catalyzes the -acetylglucosamine (GlcNAc) transformation of lipid I to lipid II during peptidoglycan biosynthesis. Park's nucleotide has been a convenient biochemical tool to study the function of MraY (phospho-MurNAc-(pentapeptide) translocase) and MurG; however, no fluorescent probe has been developed to differentiate individual processes in the biotransformation of Park's nucleotide to lipid II via lipid I. Herein, we report a robust assay of MurG using either the membrane fraction of a strain or a thermostable MraY and MurG of as enzyme sources, along with Park's nucleotide or Park's nucleotide--C-dansylthiourea and uridine diphosphate (UDP)-GlcN-C-FITC as acceptor and donor substrates.

A practical synthesis of a novel DPAGT1 inhibitor, aminouridyl phenoxypiperidinbenzyl butanamide (APPB) for in vivo studies.

Immunotherapy that targets -linked glycans has not yet been developed due in large part to the lack of specificity of -linked glycans between normal and malignant cells. -Glycan chains are synthesized by the sequential action of glycosyl transferases in the Golgi apparatus. It is an overwhelming task to discover drug-like inhibitors of glycosyl transferases that block the synthesis of specific branching processes in cancer cells, killing tumor cells selectively.

Novel FR-900493 Analogues That Inhibit the Outgrowth of Spores.

The spectrum of antibacterial activity for the nucleoside antibiotic FR-900493 () can be extended by chemical modifications. We have generated a small focused library based on the structure of and identified UT-17415 (), UT-17455 (), UT-17460 (), and UT-17465 (), which exhibit anti- growth inhibitory activity. These analogues also inhibit the outgrowth of spores at 2× minimum inhibitory concentration.

High-resolution structures of a heterochiral coiled coil.

Interactions between polypeptide chains containing amino acid residues with opposite absolute configurations have long been a source of interest and speculation, but there is very little structural information for such heterochiral associations. The need to address this lacuna has grown in recent years because of increasing interest in the use of peptides generated from d amino acids (d peptides) as specific ligands for natural proteins, e.g.

Evidence for small-molecule-mediated loop stabilization in the structure of the isolated Pin1 WW domain.

The human Pin1 WW domain is a small autonomously folding protein that has been useful as a model system for biophysical studies of β-sheet folding. This domain has resisted previous attempts at crystallization for X-ray diffraction studies, perhaps because of intrinsic conformational flexibility that interferes with the formation of a crystal lattice. Here, the crystal structure of the human Pin1 WW domain has been obtained via racemic crystallization in the presence of small-molecule additives.

Enhancement of α-helix mimicry by an α/β-peptide foldamer via incorporation of a dense ionic side-chain array.

We report a new method for preorganization of α/β-peptide helices, based on the use of a dense array of acidic and basic side chains. Previously we have used cyclically constrained β residues to promote α/β-peptide helicity; here we show that an engineered ion pair array can be comparably effective, as indicated by mimicry of the CHR domain of HIV protein gp41. The new design is effective in biochemical and cell-based infectivity assays; however, the resulting α/β-peptide is susceptible to proteolysis.