Director, International Center for Biotechnology (ICBioTech), Osaka University, Japan
Title of the talk: Regulation of Antibiotics Production in Actinomycetes
Since the discovery of many useful antibiotics for use in medicinal and agricultural fields, actinomycetes have been explored extensively. Most characteristic feature is their versatility in producing many secondary metabolites differing in chemical structures as well as biological activities. Among actinomycetes, genus Streptomyces is the most productive, and the antibiotic production is regulated by small diffusible signalling compounds called “autoregulators”.
In S. virginiae, the auturegulator called Virginiae Butanolides are controlling the production of virginiamycin, in S. lavendulae FRI-5, the autoregulator IM-2 is controlling the production of blue pigment, D-cycloserine and several nucleoside antibiotics, and in S. coelicolor A3(2) autoregulator SCBs are involved in the production of actinorhodin and undecylprodigiosine. In addition, new type of the autoregulator was recently discovered from S. avermitilis, named avenolide which controls the avermectin production in S. avermitilis.
All of the virginiae butanolides, IM-2, SCBs as well as avenolide have been purified in my laboratory and their chemical structures including stereochemistry were identified. All of them are extremely effective, acting as the initiator of antibiotics production with minimum effective concentrations of nM. Current status of the autoregulator-mediated signalling pathways including the presence of specific receptor proteins will be discussed.
Takuya Nihira has completed his PhD at the age of 27 years from Kyoto University, and have been engaging in education and research in Osaka University since 1981. He is the director of International Center for Biotechnology, a premier organization for international collaboration in the field of biotechnology. He has published more than 200 papers in reputed journals.