Construction and Cultivation of Genetically-engineered Strain to Improve Geldanamycin Production

To enhance Streptomyces hygroscopicus 17997, a geldanamycin(Gdm)-producing strain, in fermentation yield, the naphthalenic 3-amino-5-hydroxybenzoic acid (AHBA) biosynthetic genes (shnSOP), encoding the products that share the common biosynthetic substrates with Gdm, were disrupted by homologous recombination technology. The resulting mutant strain (Δ SOP) was cultivated on a solid medium, and the number of spores collected from the plates was calculated from 5 to 14 days, and the yield of Gdm was measured by high-performance liquid chromatography. The Gdm fermentation yield of Δ SOP strain was 185% more than that of the parent strain. On solid medium, the spore growth of Δ SOP strain experienced two cycles; the second generation of spores produced a higher yield of Gdm.