A primary cDNA library of Aspergillus niger H1 was constructed using the switching mechanism at the 5′ end of the RNA transcript(SMART) technique. A total of 169 clones exhibited halos when grown on tricalcium phos...A primary cDNA library of Aspergillus niger H1 was constructed using the switching mechanism at the 5′ end of the RNA transcript(SMART) technique. A total of 169 clones exhibited halos when grown on tricalcium phosphate medium, and the H-46 clone displayed a clear halo. The full-length c DNA of the clone H-46 clone was 1 407 bp in length with a complete open reading frame(ORF) of 816 bp, and it encoded a protein that contained 272 amino acids. Multiple alignment analysis revealed a high degree of homology between the ORFs of the H-46 clone and the Bax inhibitor family(BI-1-like) proteins of other fungi. Acetic acid was secreted by Escherichia coli DH5α that express the BI-1-like gene. The level attained was 492.52 mg L^(-1), which was associated with the release of 0.212 mg m L^(-1) of soluble phosphate at 28 h. These results showed that the heterologous expression of BI-1-like genes in Eschericha coli DH5α increased the secretion of acetic acid by altering the membrane permeability and enhancing the solubility of phosphate(P).展开更多
Rock phosphate (RP) is a low efficiency P fertilizer that is directly applied to the soil and can be solubilized by phosphate-solubilizing microorganisms (PSMs) in fermentation or soil conditions. This study inves...Rock phosphate (RP) is a low efficiency P fertilizer that is directly applied to the soil and can be solubilized by phosphate-solubilizing microorganisms (PSMs) in fermentation or soil conditions. This study investigated dynamic solubilization of 2 concentrations of rock phosphate in a liquid culture with different dosages of glucose by two fungal isolates,Aspergillus niger P39 and Penicillium oxalicum P66, from soybean and wheat rhizosphere soil. Although during the 20 day culture period A. niger P39 had a stronger ability to acidify the culture media than P. ozalicum P66, soluble P concentrations at glucose dosages of 30 and 50 g L^-1 with RP of 15 g L^-1 in the culture solution were much higher by P. oxalicum P66. The greater effectiveness of P. oxalicum P66 compared to A. niger P39 in the solubilization of RP was strongly associated with the production of organic acids. This study suggested that for RP solubilization the type rather than the concentration of PSM-produced organic acids was more important.展开更多
基金supported by the National Natural Science Foundation of China(41440008)
文摘A primary cDNA library of Aspergillus niger H1 was constructed using the switching mechanism at the 5′ end of the RNA transcript(SMART) technique. A total of 169 clones exhibited halos when grown on tricalcium phosphate medium, and the H-46 clone displayed a clear halo. The full-length c DNA of the clone H-46 clone was 1 407 bp in length with a complete open reading frame(ORF) of 816 bp, and it encoded a protein that contained 272 amino acids. Multiple alignment analysis revealed a high degree of homology between the ORFs of the H-46 clone and the Bax inhibitor family(BI-1-like) proteins of other fungi. Acetic acid was secreted by Escherichia coli DH5α that express the BI-1-like gene. The level attained was 492.52 mg L^(-1), which was associated with the release of 0.212 mg m L^(-1) of soluble phosphate at 28 h. These results showed that the heterologous expression of BI-1-like genes in Eschericha coli DH5α increased the secretion of acetic acid by altering the membrane permeability and enhancing the solubility of phosphate(P).
基金Project supported by the Director Fund of the Northeast Institute of Geography and Agricultural Ecology, ChineseAcademy of Sciences, and the National Agricultural Key Project of China (No. 2001BA007).
文摘Rock phosphate (RP) is a low efficiency P fertilizer that is directly applied to the soil and can be solubilized by phosphate-solubilizing microorganisms (PSMs) in fermentation or soil conditions. This study investigated dynamic solubilization of 2 concentrations of rock phosphate in a liquid culture with different dosages of glucose by two fungal isolates,Aspergillus niger P39 and Penicillium oxalicum P66, from soybean and wheat rhizosphere soil. Although during the 20 day culture period A. niger P39 had a stronger ability to acidify the culture media than P. ozalicum P66, soluble P concentrations at glucose dosages of 30 and 50 g L^-1 with RP of 15 g L^-1 in the culture solution were much higher by P. oxalicum P66. The greater effectiveness of P. oxalicum P66 compared to A. niger P39 in the solubilization of RP was strongly associated with the production of organic acids. This study suggested that for RP solubilization the type rather than the concentration of PSM-produced organic acids was more important.