In order to accelerate drug discovery, a simple, reliable, and cost-effective system for high-throughput identification of a potential antibiotic mechanism of action is required. To facilitate such screening of new antibiotics, we created a double-reporter system for not only antimicrobial activity detection but also simultaneous sorting of potential antimicrobials into those that cause ribosome stalling and those that induce the SOS response due to DNA damage. In this reporter system, the red fluorescent protein gene rfp was placed under the control of the SOS-inducible sulA promoter. The gene of the far-red fluorescent protein, katushka2S , was inserted downstream of the tryptophan attenuator in which two tryptophan codons were replaced by alanine codons, with simultaneous replacement of the complementary part of the attenuator to preserve the ability to form secondary structures that influence transcription termination. This genetically modified attenuator makes possible Katushka2S expression only upon exposure to ribosome-stalling compounds. The application of red and far-red fluorescent proteins provides a high signal-to-background ratio without any need of enzymatic substrates for detection of the reporter activity. This reporter was shown to be efficient in high-throughput screening of both synthetic and natural chemicals.

The emergence of antibiotic-resistant pathogenic bacteria in recent decades leads us to an urgent need for the development of new antibacterial agents. The species of the genus Amycolatopsis are known as producers of secondary metabolites that are used in medicine and agriculture. The complete genome sequences of the Amycolatopsis demonstrate a wide variety of biosynthetic gene clusters, which highlights the potential ability of actinomycetes of this genus to produce new antibiotics. In this review, we summarize information about antibiotics produced by Amycolatopsis species. This knowledge demonstrates the prospects for further study of this genus as an enormous source of antibiotics.

A reporter construct was created on the basis of the transcription attenuator region of the Escherichia coli tryptophan operon. Dual-fluorescent-protein genes for red fluorescent protein and cerulean fluorescent protein were used as a sensor and internal control of gene expression. The sequence of the attenuator was modified to avoid tryptophan sensitivity while preserving sensitivity to ribosome stalling. Antimicrobial compounds which cause translation arrest at the stage of elongation induce the reporter both in liquid culture and on an agar plate. This reporter could be used for high-throughput screening of translation inhibitors.