High-frequency Protoplast-transfection ofStreptomyces parvulus2297 with Actinophage R4 DNA

Abstract
High frequency transfection of Streptomyces parvulus with actinophage R4 DNA was performed by modifying the procedure of protoplast transformation of S. coelicolor A3(2) with SCP2 plasmid DNA [Bibb et al., Nature, 274, 398 (1978)]. Optimum conditions for protoplast transfection included the presence of 16~24% (w/v) polyethyleneglycol 4000, and the maximum efficiency of transfection was 3 × 10−5 per phage DNA molecule. This value was at least 100 times higher than the efficiency of previously reported transfection systems in Streptomyces.