Genomic Characterization of Micromonospora Sp. B9E7 Isolated from a Rice Field in the Bafra Plain: Taxonomic Position and Secondary Metabolite Potential

Abstract

This study comprehensively examined the genetic, metabolic, and biotechnological potential of the Micromonospora sp. B9E7 isolate. Whole-genome sequencing and digital DNA-DNA hybridization (dDDH) analyses revealed that the isolate is genetically distinct from known species, suggesting it represents a novel species. Genome annotation identified 6,826 protein-coding genes and 297 functional subsystems; however, only 18% of the genome matched known functional categories, indicating many genes remain uncharacterized. Nineteen biosynthetic gene clusters associated with secondary metabolite production were detected, some showing similarity to known antibiotic and anticancer compounds. The isolate exhibited key plant growth-promoting traits, including phosphate solubilization, siderophore production, and high indole-3-acetic acid (IAA) synthesis. Conversely, it did not produce ammonia, fix nitrogen, or show antimicrobial activity against tested pathogens. These results suggest that B9E7 promotes plant growth primarily through direct mechanisms, such as nutrient solubilization and siderophore-mediated micronutrient acquisition, rather than indirect pathogen suppression. Overall, Micromonospora sp. B9E7 emerges as a promising candidate both as a taxonomically novel species and for biotechnological applications. Future research should focus on detailed phenotypic and biochemical characterization, and functional studies of its secondary metabolites. Additionally, combining B9E7 with other beneficial microorganisms or optimizing environmental conditions may enhance its efficacy in agricultural settings.

Keywords

• Bafra plain
• Micromonospora
• Biotechnology
• Whole-genome
• Plant growth-promoting

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