Ribosomal synthesis and in situ isolation of peptide molecules in a cell-free translation system.

Although the cell-free translation system is now widely accepted as an efficient platform for production, engineering and screening of recombinant proteins, it has not been successfully used for the synthesis of peptide molecules mainly due to low expression yields and rapid proteolysis of the expressed peptides. In this study, we propose a novel strategy for rapid expression and recovery of peptide molecules which involves the rational design of template DNA and heterogenous cell-free translation reaction in the presence of affinity beads. Various peptide molecules which were not expressed in a detectable level were successfully expressed and recovered in situ in a substantial yield. We expect that the presented approach will be widely used as a versatile platform for the generation of a variety of peptide molecules.

Biological control of strawberry Fusarium wilt caused by Fusarium oxysporum f. sp. fragariae using Bacillus velezensis BS87 and RK1 formulation.

Two isolates, Bacillus sp. BS87 and RK1, selected from soil in strawberry fields in Korea, showed high levels of antagonism towards Fusarium oxysporum f. sp. fragariae in vitro. The isolates were identified as B. velezensis based on the homology of their gyrA sequences to reference strains. BS87 and RK1 were evaluated for control of Fusarium wilt in strawberries in pot trials and field trials conducted in Nonsan, Korea. In the pot trials, the optimum applied concentration of BS87 and RK1 for pre-plant root-dip application to control Fusarium wilt was 10(5) and 10(6) colony-forming units (CFU)/ml, respectively. Meanwhile, in the 2003 and 2005 field trials, the biological control efficacies of formulations of RK1 were similar to that of a conventional fungicide (copper hydroxide) when compared with a non-treated control. The RK1 formulation was also more effective than BS87 in suppressing Fusarium wilt under field conditions. Therefore, the results indicated that formulation of B.velezensis BS87 and RK1 may have potential to control Fusarium wilt in strawberries.