Competition assays performed for the <i>wt</i> (A), W531A (B), and F432A (C) proteins in the presence of both anandamide (black) and PEA (red).

<p>Each set of data was fitted using simple exponential decay functions, whose parameters are reported in S6 Table in <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1004231#pcbi.1004231.s015" target="_blank">S2 Text</a>.</p

Polar plots of the <i>φ</i> angle (dihedral angle along the Cα-Cβ axis) of Phe432 (<i>φF</i>—green dots) and Trp531 (<i>φW</i>—violet dots) with respect to the <i>d-MA</i> (red background), <i>d-T</i> (cyan background), and <i>d-AB</i> (yellow background) distances for pre-reactive conformations of the <i>wt</i>FAAH/anandamide (first row), <i>wt</i>FAAH/oleamide (second row), and <i>wt</i>FAAH/palmitoylethanolamide (PEA—third row) systems.

<p>The polar (<i>d-MA</i>, <i>d-T</i> and <i>d-AB</i>) and angular (<i>φ—</i>in red on the plot) coordinates are explicitly indicated on the plots. The approximate values of <i>φF</i> of Phe432 for the <i>“open”</i> and <i>“closed”</i> MA channel configurations are highlighted with blue dashed bars. Distances and angles are expressed in Å and degrees, respectively. Definitions of the <i>d-MA</i>, <i>d-T</i> and <i>d-AB</i> distances are reported in the Methods section. Selected snapshots from MD simulations indicating the <i>“open”</i> (left) and <i>“closed”</i> (right) MA channel configurations, as induced by the rotation of the <i>φ</i> angle of Phe432 and the cooperative Trp531, are shown at the bottom of the polar plots. The MA (red) and AB (orange) channels are represented in molecular surfaces. Phe432 (green) and Trp531 (violet) are shown in space-filling representation. The <i>φ</i> angle of the two residues is explicitly reported.</p

Time evolution of the <i>“elongated”</i> (red), <i>“hooked”</i> (yellow), and <i>“curved”</i> conformations of anandamide (first row), oleamide (second row), and PEA (third row), shown for Monomer-A (first column) and Monomer-B (second column) of the <i>wt</i>-FAAH (upper graphs) and <i>mut</i>-FAAH (lower graphs) systems.

<p>Time windows for the substrates location are shown with different background colors: red (MA channel), yellow (AB channel), and cyan (T region). The green background indicates the time windows for the oleamide unbinding in the <i>mut-</i>FAAH. Full details are in the main text, in the <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1004231#pcbi.1004231.s014" target="_blank">S1 Text</a> and in <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1004231#pcbi.1004231.s002" target="_blank">S2 Fig</a>.</p

K_m obtained from the fitting of the kinetic assays (S12 Fig).

<p>y = V_max*x/(K_m+x) (Origin Pro 8.6)</p><p>K_m obtained from the fitting of the kinetic assays (<a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1004231#pcbi.1004231.s012" target="_blank">S12 Fig</a>).</p

Overview of the FAAH protein (pdb 1MT5) [1] in complex with anandamide, embedded in a 1-palmitoyl-2-oleoyl-phosphatidylethanolamine (POPE) lipid bilayer.

<p>The enzyme is a homodimer, which is shown in gray ribbons. The lipids of the membrane are represented in cyan lines with the phosphate atoms highlighted as spheres. A close view of the binding site is shown on the right. The substrate anandamide is shown in yellow sticks, while the catalytic triad (Ser241-Ser217-Lys142) and the oxyanion hole (Ser241-Gly239-Gly240-Ser241) residues are represented in cyan sticks. The so called “membrane access” (MA—red) and the “acyl chain binding” (AB—orange) channels, as well as the “cytosolic port” (CP—cyan) are depicted in molecular surface representation. The interface region between the MA and AB channels is indicated as transition region (T). The Asp403 and Arg486 residues of the MA channel, which favor the substrates entrance within FAAH active site, are also shown as sticks. Key residues—Phe432 (green) and Trp531 (magenta)—are shown in space-filling representation. For clarity, explicit water molecules included in the simulations are omitted. The chemical structure of the FAAH substrates here considered—anandamide, oleamide, and palmitoylethanolamide (PEA)—is also shown.</p

La Lanterne : journal politique quotidien

01 octobre 18971897/10/01 (N7467,A21)

Discovery of Novel and Selective SIRT6 Inhibitors

SIRT6 is an NAD⁺-dependent deacetylase with a role in the transcriptional control of metabolism and aging but also in genome stability and inflammation. Broad therapeutic applications are foreseen for SIRT6 inhibitors, including uses in diabetes, immune-mediated disorders, and cancer. Here we report on the identification of the first selective SIRT6 inhibitors by in silico screening. The most promising leads show micromolar IC₅₀s, have significant selectivity for SIRT6 versus SIRT1 and SIRT2, and are active in cells, as shown by increased acetylation at SIRT6 target lysines on histone 3, reduced TNF-α secretion, GLUT-1 upregulation, and increased glucose uptake. Taken together, these results show the value of these compounds as starting leads for the development of new SIRT6-targeting therapeutic agents