Inhibition of recombinant Scorpine against the infection of <i>P. falciparum</i> FCC1/HN <i>in vitro</i>.

<p>(A) Recombinant Scorpine with cleavage of His-Sumo tag using SUMO protease, was added to <i>Plasmodium falciparum</i> FCC1/HN cultures at different concentrations (10 and 5 µM) for 24, 48 and 72 h. The number of infected erythrocytes was counted as described in the “Materials and methods” section. Asterisks indicate significant difference (*<i>p</i><0.05; comparision with the solvent control). (B) The representative microscopic images of the parasites treated with recombinant Scorpine for 24 h, using the microscopic examination of thin blood films stained with Giemsa (100×, oil immersion).</p

The expression analysis of recombinant Scorpine expressed in <i>E. coli</i> BL21.

<p>The expression analysis using 12% SDS–PAGE (A), Western blotting (B), and 16.5% Tricine-SDS-PAGE (C). <b>Lane 1</b>: Protein molecular weight marker; <b>lane 2</b>: Crude cells extracts of uninduced <i>E. coli</i> BL21 containing pSUMO/His-Sumo-Scorpine; <b>lane 3</b>: Crude cells extracts of induced <i>E. coli</i> BL21 containing pSUMO/His-Sumo-Scorpine; <b>lane 4</b>: Sonicated precipitate of induced <i>E. coli</i> BL21 containing pSUMO/His-Sumo-Scorpine; <b>lane 5</b>: Sonicated supernatant of induced <i>E. coli</i> BL21 containing pSUMO/His-Sumo-Scorpine; <b>lane 6</b>: Purified eluate on a nickel–nitrilotriacetic acid (Ni²⁺–NTA, Novagen) affinity chromatography column; <b>lane 7</b>: Scorpine with cleavage of His-Sumo tag using SUMO protease; <b>Black arrow</b> showed His-Sumo-Scorpine and <b>white arrow</b> showed Scorpine with cleavage of His-Sumo tag.</p

Recombinant Scorpine Produced Using SUMO Fusion Partner in <i>Escherichia coli</i> Has the Activities against Clinically Isolated Bacteria and Inhibits the <i>Plasmodium falciparum</i> Parasitemia <i>In Vitro</i>

<div><p>Scorpine, a small cationic peptide from the venom of Pandinus imperator, which has been shown to have anti-bacterial and anti-plasmodial activities, has potential important applications in the pharmaceutical industries. However, the isolation of scorpine from natural sources is inefficient and time-consuming. Here, we first report the expression and purification of recombinant scorpine in <i>Escherichia coli,</i> using small ubiquitin-related modifier (SUMO) fusion partner. The fusion protein was expressed in soluble form in <i>E. coli</i>, and expression was verified by SDS-PAGE and western blotting analysis. The fusion protein was purified to 90% purity by nickel–nitrilotriacetic acid (Ni²⁺–NTA) resin chromatography. After the SUMO-scorpine fusion protein was cleaved by the SUMO protease, the cleaved sample was reapplied to a Ni²⁺–NTA column. Tricine/SDS-PAGE gel results indicated that Scorpine had been purified successfully to more than 95% purity. The recombinantly expressed Scorpine showed anti-bacterial activity against two standard bacteria including <i>Staphylococcus aureus</i> ATCC 29213 and <i>Acinetobacter baumannii</i> ATCC 19606, and clinically isolated bacteria including <i>S. aureus</i> S, <i>S. aureus</i> R, <i>A. baumannii</i> S, and <i>A. baumannii</i> R. It also produced 100% reduction in <i>Plasmodium falciparum</i> parasitemia <i>in vitro</i>. Thus, the expression strategy presented in this study allowed convenient high yield and easy purification of recombinant Scorpine for pharmaceutical applications in the future.</p></div

Inhibition of recombinant Scorpine against the biofilm formation indices of bacteria.

<p>(A) <i>S. aureus</i> ATCC 29213 (B) <i>S. aureus</i> S (C) <i>S. aureus</i> R (D) <i>A. baumannii</i> ATCC 19606 (E) <i>A. baumannii</i> S (F) <i>A. baumannii</i> R cultured in the presence of recombinant Scorpine for 24 h. Different letters (A–C) are significantly different within treatments at <i>p</i><0.05.</p

Minimum inhibitory concentrations of selected antibiotics against <i>S. aureus</i> and <i>A. baumannii</i>.

<p>Note: Minimum inhibitory concentrations (MIC, µg/ml).</p

Schematic of the chain of events conducted within the 1-3-7 time windows.

<p>IRS, indoor residual spraying.</p

Shifts in the spatial and temporal scales of reporting and response as countries progress towards malaria elimination.

<p>Shifts in the spatial and temporal scales of reporting and response as countries progress towards malaria elimination.</p

Diagram of the data reporting and feedback system for 1-3-7.

<p>CDC, China CDC; PSTN, public switched telephone network; SMS, short message service; VPN, virtual private network.</p

Implementation progress of the 1-3-7 strategy in China.

<p>MoH, Ministry of Health; S&R, surveillance and response.</p

<i>Culex pipiens pallens</i> mosquito mortality rate in standard WHO deltamethrin resistance bioassay.

<p><i>Culex pipiens pallens</i> mosquito mortality rate in standard WHO deltamethrin resistance bioassay.</p