Antibiotics from Insect-Associated Actinobacteria

SIMPLE SUMMARY: Actinobacteria remain a key source for antibiotic discovery, and the current antimicrobial resistance crisis is becoming a driving force for actinobacteria research. Insect-associated actinomycetes are an underexplored ecological niche with prospects for the search for novel antimicrobial compounds. The described associations of leaf-cutter ants and Pseudonocardia bacteria or solitary wasps and Streptomyces bacteria were the first examples of mutually beneficial coexistence of insects with actinobacteria. On the molecular level, these systems are regulated by antibiotics. The complex relationships between insects and actinobacteria mediated by antibiotics could be important for the stability of ecosystems and agricultural production. ABSTRACT: Actinobacteria are involved into multilateral relationships between insects, their food sources, infectious agents, etc. Antibiotics and related natural products play an essential role in such systems. The literature from the January 2016–August 2022 period devoted to insect-associated actinomycetes with antagonistic and/or enzyme-inhibiting activity was selected. Recent progress in multidisciplinary studies of insect–actinobacterial interactions mediated by antibiotics is summarized and discussed.