The best pose of inhibitor docked into the active site of NDM-1.

<p>Oligopeptides 2 (Fig 3A) and 5 (Fig 3B) are shown as stick model. Water-bridge and two zinc ions are shown as sphere model (red and black, respectively). Seven key amino acids in catalytic center of NDM-1 (His189, His120, His122, Asp124, Cys208, His250 and Tyr229) treated as flexible residues are shown as line model.</p

Synergistic antibacterial activity of inhibitory oligopeptides in combination with ertapenem against genetically engineered bacterium of <i>E</i>. <i>coli</i> BL21 (DE3)/pET30a-NDM-1 and a clinical isolate of <i>P</i>. <i>aeruginosa</i> ^a.

<p>Synergistic antibacterial activity of inhibitory oligopeptides in combination with ertapenem against genetically engineered bacterium of <i>E</i>. <i>coli</i> BL21 (DE3)/pET30a-NDM-1 and a clinical isolate of <i>P</i>. <i>aeruginosa</i> <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0177293#t003fn001" target="_blank">^a</a>.</p

The partial charge values of water-bridge, two zinc ions, and critical atoms of inhibitors.

<p>Oligopeptides 2 (Fig 4A) and 5 (Fig 4B) are shown as stick model, which sulfur atom and oxygen atom are colored by yellow and red, respectively. Water-bridge and two zinc ions are shown as sphere model (red and black, respectively).</p

Results of the binding free energy calculated by MM-PBSA.

<p>Results of the binding free energy calculated by MM-PBSA.</p

Binding model between inhibitor and target of NDM-1 enzyme.

<p>Binding models of the docked NDM-1 with oligopeptides 2 (Fig 2A) and 5 (Fig 2B), respectively. Structures of inhibitors were shown in stick model. NDM-1 was shown as ribbon model. Six key amino acids binding two zinc ions are colored by pink.</p

MIC values of β-lactam antibiotics determined by the E-test method at 24 h.

<p>MIC values of β-lactam antibiotics determined by the E-test method at 24 h.</p

Inhibitory activities of oligopeptides against full-length NDM-1.

<p>Inhibitory activities of oligopeptides against full-length NDM-1.</p

GP73 represses host innate immune response to promote virus replication by facilitating MAVS and TRAF6 degradation

<div><p>Hepatitis C virus (HCV) infection is a leading cause of chronic liver diseases and hepatocellular carcinoma (HCC) and Golgi protein 73 (GP73) is a serum biomarker for liver diseases and HCC. However, the mechanism underlying GP73 regulates HCV infection is largely unknown. Here, we revealed that GP73 acts as a novel negative regulator of host innate immunity to facilitate HCV infection. GP73 expression is activated and correlated with interferon-beta (IFN-β) production during HCV infection in patients’ serum, primary human hepatocytes (PHHs) and human hepatoma cells through mitochondrial antiviral signaling protein (MAVS), TNF receptor-associated factor 6 (TRAF6) and mitogen-activated protein kinase kinase/extracellular regulated protein kinase (MEK/ERK) pathway. Detailed studies revealed that HCV infection activates MAVS that in turn recruits TRAF6 <i>via</i> TRAF-interacting-motifs (TIMs), and TRAF6 subsequently directly recruits GP73 to MAVS <i>via</i> coiled-coil domain. After binding with MAVS and TRAF6, GP73 promotes MAVS and TRAF6 degradation through proteasome-dependent pathway. Moreover, GP73 attenuates <i>IFN-β</i> promoter, IFN-stimulated response element (ISRE) and nuclear factor κB (<i>NF-κB</i>) promoter and down-regulates <i>IFN-β</i>, <i>IFN-λ1</i>, interleukin-6 (<i>IL-6</i>) and IFN-stimulated gene 56 (<i>ISG56</i>), leading to the repression of host innate immunity. Finally, knock-down of <i>GP73</i> down-regulates HCV infection and replication in Huh7-MAVSR cells and primary human hepatocytes (PHHs), but such repression is rescued by GP73m4 (a mutant GP73 resists to GP73-shRNA#4) in Huh7-MAVSR cells, suggesting that GP73 facilitates HCV infection. Taken together, we demonstrated that GP73 acts as a negative regulator of innate immunity to facilitate HCV infection by interacting with MAVS/TRAF6 and promoting MAVS/TRAF6 degradation. This study provides new insights into the mechanism of HCV infection and pathogenesis, and suggests that GP73 is a new potential antiviral target in the prevention and treatment of HCV associated diseases.</p></div