In order to enable the streptovaricin biosynthetic study by in vivo gene disruption,it is crucial to develop a genetic modification system for producer Streptomyces spectabilis NRRL 2494.This study aimed to construct the method of conjugation to transfer exotic DNA into Streptomyces spectabilis NRRL 2494.A putative streptovaricin amide synthase gene svaF was disrupted in vivo,and the resulting plasmid was transferred into Streptomyces spectabilis NRRL 2494 by conjugation through a double-crossover recombination event.