Transfection of protoplasts from Streptomyces lividans 66 with actinophage SH10 DNA.

The slightly modified procedure for the transformation of protoplasts of S. coelicolor A3 (2) with SCP2 plasmid DNA and polyethylenglycol (PEG) (Bibb et al., 1978) was extended to infection of protoplasts of S. lividans 66 with actinophage SH10 DNA (Klaus et al., 1979). Maximal yield of transfected protoplasts was obtained at 20% PEG, 3 MM sodium-citrate and 150 mM NaCl final concentrations. The efficiency of transfection was determined to be about 2 x 10(-8) to 2 x 10(-7). The average value of competent protoplasts was about 1-2 x 10(-4) of regenerating protoplasts. In comparison with outgrowing spores infected with phage particles the average burst size of transfected protoplasts was reduced from 100 to 10 pfu/infected cell, the latent period prolonged from 45 min to 120 min and the rise period was not affected.