Heavy‐ion mutagenesis significantly enhances enduracidin production by Streptomyces fungicidicus

Abstract

To improve fermentative production of enduracidin, heavy‐ion beams generated by the Heavy Ion Research Facility in Lanzhou (HIRFL), China, were employed for the first time to generate mutations in Streptomyces fungicidicus. Initial screening detected 44 positive mutants with larger inhibition zone, which were subsequently tested based on flask fermentation. Finally, 20 mutants showed 20% increase in enduracidin production, when compared with the original strain. Among them, enduracidin production by the three mutants (M13, M30, and M34) was significantly higher than that by the original strain. In particular, mutant M30 exhibited highest enduracidin production, which was 114% higher than that obtained with the original strain. Following culture optimization, the maximal enduracidin yield obtained by M30 reached 918.5 mg/L in 10 days, which was 34% higher than that noted in the control.

Enhancement of Enduracidin Accumulation from Sweet Sorghum Juice via Alleviation of Oxidative Damage in Streptomyces Fungicidicus M30

“…Strains and media S. fungicidicus M30 was used for enduracidin production, and was cultivated on agar plates at 28 °C for 7 d, as described in a previous report [31]. The seed culture medium and conditions of propagation were prepared according to our previous study [31]. The seed medium included 30 g/L glucose, 30 g/L corn steep liquor, 20 g/L CaCO 3 , 8 g/L NaCl, 5 g/L yeast extract, with the pH of the medium adjusted to 7.5.…”

“…1 mL spore suspension of S. fungicidicus M30 (3 × 10 7 cells/mL) was inoculated into 50 mL of seed medium and cultured at 28 °C on a SPH-311D rotary incubator (Shanghai Shiping Laboratory Equipment Co., Ltd, China) at an agitation speed of 220 rpm for 2 d [31]. Subsequently, The 4% (v/v) seed medium was transferred into 50 mL of fermentation medium at 50 °C and 220 rpm.…”

Effects of Carbon Ion Beam-induced Mutagenesis for the Screening of RED Production-deficient Mutants of Streptomyces Coelicolor JCM4020

“…Radiation doses giving a surviving fraction of 1-10% have been proposed for effective mutagenesis in microorganisms. 33 The use of a sample with a lower survival rate may increase the number of mutants exhibiting abnormal RED production, but it may also increase multiple undesired mutations in the genome, leading to di culty identifying the genes responsible for the phenotype. We then tested the growth on minimal medium and the formation of aerial mycelium for 118 mutants, 59 of which showed no de ciency (Figure 1).…”

“…It has been proposed that radiation doses that leave a surviving fraction of a population of 1-10% are effective for achieving mutagenesis in microorganisms. 33 Regarding the application of heavy-ion mutagenesis to Streptomyces spp., several examples that show the improved production of useful secondary metabolites have been reported. [33][34][35] However, because the number of applications using heavy-ion mutagenesis for bacteria is still limited, and the mutants have not been comprehensively characterized at the genome scale, there is still a need to understand the signature of mutations in the Streptomyces genome.…”

“…33 Regarding the application of heavy-ion mutagenesis to Streptomyces spp., several examples that show the improved production of useful secondary metabolites have been reported. [33][34][35] However, because the number of applications using heavy-ion mutagenesis for bacteria is still limited, and the mutants have not been comprehensively characterized at the genome scale, there is still a need to understand the signature of mutations in the Streptomyces genome. 28,29 In this study, we performed mutagenesis using carbon ions ( 12 C 5+ ) on Streptomyces coelicolor JCM4020 and screened RED-de cient mutants under conditions where this strain could interact with T. pulmonis TP-B0596.…”