Abstract
Streptomyces roseoflavus Men-myco-93-63 was isolated from potato scab (S. scabies) decline soil as an antagonistic strain, which can effectively inhibit several phytopathogenic fungi and control important related plant diseases. In this study, cosynthesis and different expression protein analysis between seven antibiotic synthesized-blocked mutants of Men-myco-93-63 were carried out. Two-dimensional gel electrophoresis was used to compare proteins of cosynthesis and non-cosynthesis mutants. By matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, two different protein spots were isolated and identified to be homologous proteins of ectoine hydroxylase and transcriptional regulator (DeoR family protein), which could be related to the biosynthesis of antibiotics of S. roseoflavus Men-myco-93-63.