S. PhornphisutthimasN. SudtachatC. BunyooP. ChotewutmontriB. PanijpanA. ThamchaipenetKasetsart UniversityMahidol UniversitySrinakharinwirot University2018-09-242018-09-242010-01-01Letters in Applied Microbiology. Vol.50, No.5 (2010), 530-5361472765X026682542-s2.0-77950463542https://repository.li.mahidol.ac.th/handle/20.500.14594/29278Aims: To develop an intergeneric conjugation system for rimocidin-producing Streptomyces rimosus. Methods and Results: High efficiencies of conjugation [10-2-10-3transconjugants/recipient colony forming units (CFU)] were obtained when spores of S. rimosus were heat treated at 40°C for 10 min prior to mixing with E. coli ET12567(pUZ8002/pIJ8600) as donor. Mycelium from liquid grown cultures of S. rimosus could also be used as recipient instead of spores, with 24-h cultures giving optimal results. TSA (Oxoid) medium containing 10 m mol l-1MgCl2was the preferred medium for conjugation. Southern hybridization was used to confirm that transconjugants of S. rimosus contained a single copy of pIJ8600 integrated at a unique chromosomal attachment site (attB). The transconjugants exhibited a high stability of plasmid integration and showed strong expression of green fluorescent protein when using pIJ8655 as the conjugative vector. Conclusion: Intergeneric conjugation between E. coli and S. rimosus was achieved at high efficiency using both spores and mycelium. Significance and Impact of the Study: The conjugation system developed provides a convenient gene expression system for S. rimosus R7 and will enable the genetic manipulation of the rimocidin gene cluster. © 2010 The Authors. Journal compilation © 2010 The Society for Applied Microbiology.Mahidol UniversityImmunology and MicrobiologyArticleSCOPUS10.1111/j.1472-765X.2010.02835.x