Nysfungin Production Improvement by UV Mutagenesis in Streptomyces noursei D-3-14

Abstract

Streptomyces noursei D-3-14 was taken as a starting strain and treated with UV (15 W, 30 cm) mutagenesis for 40 s for three consecutive rounds. High yielding strains were screened using chemical and biological potency determination, and the components of the fermentation products were detected using HPLC. Finally, the mutant strain Streptomyces noursei 72-22-1 with a chemical potency of 8912 (U/mL) and a biological potency of 5557 (U/mL) was obtained after the genetic stability evaluation. After optimization of the fermentation conditions, the chemical potency and biological potency of Streptomyces noursei 72-22-1 reached 14,082 U/mL and 10579 U/mL, respectively, which is 1.58 and 1.91 times those before optimization. HPLC analysis indicated that the mutant strain 72-22-1 displayed a higher content of polyfungin B. When equimolar nystatin A1, A3, and polyfungin B were tested for their fungicidal activities towards Saccharomyces cerevisiae ATCC 2061, polyfungin B exhibited a better efficacy than nystatin A1 and A3.

Generation of New Glycoanalogues of Polyene Antibiotics by Synthetic Biology—Testing Current Technical Boundaries

“…The second class of hyperglycosylated polyene contains two unlinked monosaccharides, the standard mycosamine and a neutral deoxysugar attached to the opposite end of the macrolactone ring. These include nystatin A3, nystatin analogues modified with L-mycarose at C35 (Figure 3), polyfungin, and candidinin [1,[18][19][20][21][22][23]. The sugar residue on C35 does not block activity [18].…”