A High-Throughput Method Based on Microculture Technology for Screening of High-Yield Strains of Tylosin-Producing Streptomyces fradiae

Abstract

Tylosin is a potent veterinary macrolide antibiotic produced by the fermentation of Streptomyces fradiae ; however, it is necessary to modify S. fradiae strains to improve tylosin production. In this study, we established a high-throughput, 24-well plate screening method for identifying S. fradiae strains that produce increased yields of tylosin. Additionally, we constructed mutant libraries of S. fradiae via ultraviolet (UV) irradiation and/or sodium nitrite mutagenesis. A primary screening of the libraries in 24-well plates and UV spectrophotometry identified S. fradiae mutants producing increased yields of tylosin. Mutants with tylosin yield 10% higher than the wild-type strain were inoculated into shake flasks, and the tylosin concentrations produced were determined by high-performance liquid chromatography (HPLC). Joint (UV irradiation and sodium nitrite) mutagenesis resulted in higher yields of mutants with enhanced tylosin production. Finally, 10 mutants showing higher tylosin yield were re-screened in shake flasks. The yield of tylosin A by strains UN-C183 (6767.64 ± 82.43 μg/ml) and UN-C137 (6889.72 ± 70.25 μg/ml) was significantly higher than that of the wild-type strain (6617.99 ± 22.67 μg/ml). These mutant strains will form the basis for further strain breeding in tylosin production.

Application of Atmospheric and Room-Temperature Plasma (ARTP) to Microbial Breeding

“…Subsequently, through fermentation condition optimization, the neomycin sulfate concentration of the strain Sf6-2 was increased by 100%. Similarly, Yao et al [ 21 ] identified 10 high-yield tylosin-producing strains from a mutant library of S. fradiae using a high-throughput 24-well plate screening method and UV spectrophotometry. Further, re-screening in shake flasks led to the identification of two strains with significantly higher tylosin A production than the wild-type strain.…”

Analysis of Secondary Metabolite Synthesis Potential of Streptomyces fradiae sf106 Based on the Whole Genome and Non-Target Metabolomics and Exploration of the Biosynthesis of Tylosin

“…Due to its economic value and application potential, extensive scientific research on tylosin biosynthesis has been conducted since the 1970s [34][35][36][37]. The existing research is mainly based on gene editing, mutagenesis, and other technologies to increase the yield of tylosin [38][39][40][41][42]. In the early stages of our laboratory, a strain of Streptomyces fradiae named sf106 was preserved (BioProject ID: PRJNA1017371).…”