ABSTRACT
Objective To develop prototype foamy virus (PFV) detection method by loop-mediated isothermal amplification. Methods Three pairs of primers targeting core region of PFV integrase were designed in this study and Bst DNA polymerase was used to amplify target sequence at 63℃. The system was established with all the conditions optimized. Results The method was established with the plasmid containing target sequence as the template. This method could specifically detect PFV infectious clone, no crossreaction was observed with human immunodeficieney virus infectious clone, bovine immunodefieiency virus infectious clone and bovine foamy virus infectious clone as templates. The detection capability of this system was 50 copy, one order more sensitive than PCR. The amplification could be finished in 15 min and human genomic DNA did not adversely affect the amplification efficiency. Conclusion The PFV detection method by loop-mediated isothermal amplification was established and it had potential usefulness in PFV detection.
ABSTRACT
Bioleaching of Cu and Fe in low-grade chalcopyrite using Penicillium janthinellum strian GXCR was studied. As a result, shaking bioleaching was more efficient than submerged bioleaching; Cu bioleaching was much better than Fe bioleaching; under conditions of optimum carbon source (10% sucrose, W/V), optimum nitrogen source (1.5% NaNO3, W/V), shaking bioleaching and the optimum combination of conditions (initial pH 6.0 in leaching media, 5% (W/V) 200-mesh ore and initial inocula of 3.0x10(5) conidia/mL), Cu bioleaching efficiency reached 87.31% (W/W). One of the most important factors affecting Cu bioleaching in shaking bioleaching was the initial pH in leaching media (F > F0.05). The major organic acids for Cu and Fe bioleaching were citric and oxalic acids, respectively. Low bioleaching efficiency by submerged bioleaching was due to low production of citric and oxalic acids. The mechanisms employed by the GXCR in Cu bioleaching included biochemical functions of citric and oxalic acids as well as ore crack caused by mechanical power generated from mycelial growth.