Cloning of relA from Actinoplanes teichomyceticus ATCC31121 and Its Application Seung-Yong Park

The relA gene encoding the highly phosphorylated guanine nucleotide, ppGpp synthetase, which performs a central role in triggering antibiotic biosynthesis and morphological differentiation in Streptomyces species, was cloned from the non- Streptomyces actinomycetes, Actinoplanes teichomyceticus ATCC31121, which produces teicoplanin, and relA antibiotic productionincreasing activity was confirmed. A 3.5-kb DNA fragment including an intact 2,466 bp open reading frame (ORF) evidencing high homology with the ppGpp synthetase (RelA) of Streptomyces species was acquired via polymerase chain reaction (PCR) using a newly designed primer based on the amino acid sequence of the previously studied RelA and Southern hybridization using the PCR product as a probe. S. lividans TK24 and A. teichomyceticus introduced with a high expression vector of the relA evidenced a 13- and 3-fold higher levels of actinorhodin and teicoplanin production, thus confirming for the first time that the high expression of relA derived from A. teichomyceticus is responsible for the induction of antibiotic production in Streptomyces species as well as in the non- Streptomyces actinomycetes, A. teichomyceticus .