Molecular physiological studies on actinomycetes for a fundamental understanding of antibiotics


  Originally, an antibiotic is defined as a chemical compound that is produced by a microorganism, suppresses the growth of other microorganisms, and has little toxicity to animals. Speaking of antibiotics, almost everyone can imagine this effect. Meanwhile, it remains a profound mystery what roles antibiotics play in the natural world. With multi-drug resistant bacteria emerging one after another, the discovery of novel antibiotics and the development of alternatives to antibiotics are becoming increasingly crucial. The number of newly discovered antibiotics, usually isolated from secondary metabolites of microorganisms including actinomycetes, have been declining. To solve this predicament, in addition to continuing the development of novel antibiotics and alternatives to antibiotics, it would be of utmost important to understand the fundamental workings of antibiotics themselves, antibiotic-producing microorganism, and antibiotic resistance.

   Our latest findings demonstrate that ribosome-targeting antibiotics not only functions as an antimicrobial but also can act as an activator for secondary metabolism of actinomycetes. Given this physiological fact, our laboratory has been analyzing the concentration-dependent activities of antibiotics at the molecular level with the hope of uncovering mysteries such as mechanisms for secondary metabolism in actinomycetes and the roles of antibiotics in the natural world. We are going to perform molecular physiological studies on actinomycetes while being exposed to some of the challenges and questions surrounding antibiotics. 

 

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