Genome Features and Secondary Metabolites Biosynthetic Potential of the Class Ktedonobacteria

In this study, we observed the existence of a putative “megaplasmid,” multiple copies of ribosomal RNA operons, and high ratio of hypothetical proteins with unknown functions in the class Ktedonobacteria. Furthermore, a total of 104 antiSMASH-predicted putative biosynthetic gene clusters (BGCs) for secondary metabolites with high novelty and diversity were identified in nine Ktedonobacteria genomes. Our investigation of domain composition and organization of the non-ribosomal peptide synthetase and polyketide synthase BGCs further supports the concept that class Ktedonobacteria may produce compounds structurally different from known natural products. Furthermore, screening of bioactive compounds from representative Ktedonobacteria strains resulted in the identification of broad antimicrobial activities against both Gram-positive and Gram-negative tested bacterial strains. Based on these findings, we propose the ancient, ubiquitous, and spore-forming Ktedonobacteria as a versatile and promising microbial resource for natural product discovery. Introduction The discovery and clinical application of antimicrobial drugs have greatly improved our well-being with regard to microbial infection over the past several decades (Demain and Sanchez, 2009). However, misuse and overuse of antibiotics has led to the accelerating development of antibiotic resistance in pathogens, which has become a major threat to modern health care and the natural environment (Pal et al...
Source: Frontiers in Microbiology - Category: Microbiology Source Type: research