Transfer properties of nif-plasmid pEA 9 by pEA 9::Tn5-Mob

pEA 9::Tn5-Mob에 의한 nif-plasmid pEA 9의 transfer 성질

Using a Tn5-Mob system, pEA9 was characterized as a self-transmissible plasmid carrying a kanamycin resistance marker. The self-transfer frequencies of pEA9 varied greatly depending on pH values. The transfer frequency was about $4\times 10^{-5}$ at pH 5, that was 10 times higher than one at pH 6.5. With a helper plasmid, transfer frequencies were increased about $10^{4}$ times than the frequencies obtained without it.