A visualization reporter system for characterizing antibiotic biosynthetic gene clusters expression with high-sensitivity

Abstract

The crisis of antibiotic resistance has become an impending global problem. Genome sequencing reveals that streptomycetes have the potential to produce many more bioactive compounds that may combat the emerging pathogens. The existing challenge is to devise sensitive reporter systems for mining valuable antibiotics. Here, we report a visualization reporter system based on Gram-negative bacterial acyl-homoserine lactone quorum-sensing (VRS-bAHL). AHL synthase gene (cviI) of Chromobacterium violaceum as reporter gene is expressed in Gram-positive Streptomyces to synthesize AHL, which is detected with CV026, an AHL deficient mutant of C. violaceum, via its violacein production upon AHL induction. Validation assays prove that VRS-bAHL can be widely used for characterizing gene expression in Streptomyces. With the guidance of VRS-bAHL, a novel oxazolomycin derivative is discovered to the best of our knowledge. The results demonstrate that VRS-bAHL is a powerful tool for advancing genetic regulation studies and discovering valuable active metabolites in microorganisms.

Rethinking Biosynthesis of Aclacinomycin A

“…When an endogenous QS system was combined with CRISPR interference, the resulting circuits precisely regulated gene expression and resulted in a 560% increase in rapamycin production in S. rapamycinicus [ 150 ]. A Gram-negative bacterial QS system was also engineered in Streptomyces , leading to the improved production of oxazolomycin [ 151 ]. In particular, gene expression was regulated by DNA methylation, which hampered the binding of RNA polymerases to promoters or transcription factors to their recognization sites at a pretranscriptional level in bacteria [ 152 , 153 ].…”