• Korean Journal of Microbiology
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• v.27 no.4
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• pp.366-372
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• 1989

Twenty-one strains were tested for 11$\beta$-hydroxylation of Reichstein's substance S. Four fungi exhibited ability for the reaction, among which Pellicularia fillamentosa showed the highest activity. The 11$\beta$-hydroxylase of this fungus was proved to be induced by the substrate, cycloheximide reducing significantly the activity of the enzyme. Range of optimum pH for the 11$\beta$-hydroxylation was broad and found to be 2.0-8.0. Test of the enzyme activity at different growing stages, from spore to mycelia, showed that the branching stage of hyphae and the mature mycelial stage were the most effective for the Reichstein's substance S transformation. However, 11$\beta$-hydroxylase in the intact spore was turned out to be uninducible with the substrate.